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37th Canadian High Polymer Forum
37e Colloque Canadien sur les Polymères
August 9 to 11, 2016 9 au 11 août 2016
Glen House Resort, Gananoque, ON
Book of Abstracts Résumés du Congrès
With many thanks to our sponsors Sincères remerciements à nos commanditaires
CANADIAN HIGH POLYMER FORUM
COLLOQUE CANADIEN SUR LES POLYMÈRES
Forum Lecturers / Conférenciers pléniers
Year / Année
1949
Location / Lieu
Hamilton
Lecturer / Conférencier
R. Fuoss 1950 Ottawa G. Stachard 1951 Kingston H. Spurlin 1952 Montréal --- 1953 London D. Riley 1955 St. Catherines R. Anthony 1956 Sarnia J. Hermans 1958 Ste-Anne-de-Bellevue G. Gee 1959 Toronto C. Bamford 1960 Ste-Marguerite F. Dainton 1962 Windsor A. Keller 1964 Ste-Marguerite C. Sadron 1965 Ottawa F. Danusson 1967 Québec S. Okamura 1969 Kingston A. Chapiro 1971 Waterloo E. Fischer 1973 St-Jean G. Smets 1975 Hamilton E. Andrews 1977 Ottawa P. Rempp 1979 Québec H. Ringsdorf 1981 Kingston P.G. de Gennes 1983 Waterloo I.M. Ward 1985 Mont-Gabriel P. Teyssie 1987 Ottawa R.H. Ottewill 1989 Mississauga A.S. Hay 1991 Mont-Gabriel W.J. Feast 1993 Gananoque G. Riess 1996 Sarnia D.A. Tirrell 1998 Lac Beauport D. Briggs 2000 Aylmer K. Matyjaszewski 2002 Aylmer M. Möller 2005 Aylmer C. Ober 2007 Gananoque T. Swager 2010 Mont-Gabriel R. McCullough 2012 Gananoque R. Waymouth 2014 Gananoque M. Hillmyer 2016 Gananoque C.J. Hawker
NOVA CHEMICALS KEYNOTE LECTURER
CONFÉRENCIER PLÉNIER NOVA CHEMICALS
Professor Craig J. Hawker, Department of Chemistry, University of California Santa Barbara
Doing new things with old tricks – Synthesis of precision materials
Craig Jon Hawker received his undergraduate degree in Chemistry from the University of Queensland, Australia in 1981. After graduating, he went to the University of Cambridge in the UK to study the biosynthesis of Vitamin B12 under Prof. Sir A. R. Battersby. Upon finishing his doctorate, Craig ventured to the United States to do his post-doctoral work with Professor J.M.J. Fréchet at Cornell University. Craig began his professional career in 1990 as a Queen Elizabeth II Research fellow at the University of Queensland before being hired by IBM in 1993 to work at the Almaden Research Center. He moved to the University of California Santa Barbara in 2004 and is now director of the California Nanosystems Institute, Dow Materials Institute, and Co-Director of the Materials Research Lab at UCSB. He holds the Alan and Ruth Heeger Chair in Interdisciplinary Science and is the Clarke Professor within CNSI. Craig is a member of the Materials Department and the Department of Chemistry and Biochemistry at UCSB.
Doing new things with old tricks – Synthesis of precision materials
Craig J. Hawker
Materials Department University of California, Santa Barbara
USA Email: hawker@mrl.ucsb.edu
A versatile strategy will be described for the multi‐gram synthesis of discrete oligomers from
commercially available monomer families, e.g., acrylates, styrenics, siloxanes. Central to this strategy is the
identification of reproducible procedures for the separation of oligomer mixtures using automated flash
chromatography systems with the effectiveness of this approach demonstrated through the multi‐gram
preparation of discrete oligomer libraries (Đ = 1.0). Synthetic availability, coupled with accurate structural
control, allows these functional building blocks to be harnessed for both fundamental studies as well as
targeted technological applications.
Keynote
Final Program / Programme Final
37th High Polymer Forum, August 9‐11, 2016 37e Colloque canadien sur les polymères, 9‐11 août 2016
Registration / Inscription
Monday August 8, from 19:30 to 21:00 (PM) Lundi 8 août, de 19:30 à 21:00 (PM)
Tuesday August 9, from 7:30 to 8:30 (AM) Mardi 9 août, de 7:30 à 8:30 (AM)
Tuesday August 9, 2016 / Mardi 9 août 2016
Theme: Biomedical applications / Thème : Applications biomédicales
Chairperson / Président : TBA
8:30 8:40 Opening remarks from the conference chair / Ouverture du colloque par le président, Jianping Lu
8:40 9:10 I‐1 Invited speaker / Conférencier invité : Jung Kwon (John) Oh, Concordia UniversityML‐MSRD Strategy for Block Copolymer Micelles for Accelerated Drug Release and Cancer Therapy
9:10 9:30 O‐1 Christopher J. Barrett, Michael Landry, Frederic Rollet and Daniel de Biasio, McGill University Some New Opto‐Reversible Polymers Inspired by Nature: New Light on the Nano‐Bio Interface
9:30 9:50 O‐2 Jifu Mao, Hyun Jin Park, Yongliang Wang, Mahmoud Rouabhia and Ze Zhang, Université Laval Highly Flexible Free‐Standing Conductive Polypyrrole Membrane
9:50 10:10 O‐3 T. Zhang, S. Taylor, M. Palmer and Jean Duhamel, University of Waterloo Membrane Binding and Oligomer Formation by the Calcium‐Dependent Lipopeptide Antibiotic A54145: A Quantitative Study with Pyrene Excimer Fluorescence
10:10 10:30 O‐4 Sung Hwa Hong and Jung Kwon Oh, Concordia University Formation of Enzyme and Oxidation Dual‐sensitive Nanocarriers via Thiol‐ene Click Reaction for Efficient Targeted and Controlled Anticancer Drug Delivery
10:30 10:50 Pause / Break
Theme: Amphiphilic and stimuli‐responsive polymersThème : Polymères amphiphiles et sensibles à des stimuli10:50 11:10 O‐5 Xili Lu, Hesheng Xia and Yue Zhao, Université de Sherbrooke
Remoldable Azobenzene Liquid Crystalline Networks Displaying Light‐Driven Motions
11:10 11:30 O‐6 Yu Wang, Guojun Liu, Heng Hu, Terry Yantian Li, Amer M. Johri, Xiaoyu Li and Jian Wang, Queen’s University Stable Water‐Dispersible Air Nanobubbles Encapsulated with ABC Triblock Copolymer Bearing Fluorinated Block with Super‐Low Surface Energy
11:30 11:50 O‐7 Yong‐Guang Jia and X. X. Zhu, Université de Montréal Complex Thermo‐Responsive Behaviors of Select Block Copolymers
11:50 13:00 Lunch / Dîner
Theme: Conducting polymers / Thème : Polymères conducteurs
Chairperson / Président : TBA
13:00 13:30 I‐2 Invited speaker / Conférencier invité : Jean‐François Morin, Samuel Caron and Charles‐Olivier Gilbert, Université Laval
Carbon‐Rich 2D Polymers: Toward Non‐Graphene Semiconducting Materials
13:30 14:00 I‐3 Invited speaker / Conférencier invité : Derek J. Schipper, University of Waterloo Reaction Development for the Synthesis of Conjugated Polymers
14:00 14:20 O‐8 Joseph A. Paquette, Sabastine Ezugwu, Giovanni Fanchini and Joe B. Gilroy, Western University Synthesis, Characterization, and Switchable Thin‐Film Conductivity of 6‐Oxoverdazyl Radical Polymers Prepared via ROMP
14:20 14:40 O‐9 Vladimir Kardelis, Ryan C. Chadwick, Kelvin Li and Alex Adronov, McMaster University “Click” Functionalization of Conjugated Polymers by Strain‐Promoted Cycloaddition
14:40 15:00 O‐10 Zhao Li, Patrick R. L. Malenfant, Jianfu Ding and Jacques Lefebvre, National Research Council Canada Semiconducting SWCNT: From Materials to Thin Film Transistors
15:00 15:20 Pause / Break
Theme: Materials with tailored propertiesThème : Matériaux à propriétés modulées15:20 15:40 O‐11 Hanno Erythropel, Roya Jamarani, Richard Leask, Milan Marić and Jim
Nicell, McGill University Development of Green Plasticizers: A Case Study
15:40 16:00 O‐12 Ahmad Raza Ashraf, Leonardo C. Simon and Zareen Akhter, University of Waterloo Dianhydride Architecture Effects on Thermal and Mechanical Properties of Polyimides
16:00 16:20 O‐13 Jun Xiang, Xia Tong and Yue Zhao, Université de Sherbrooke Spatial Organization and Optical Properties of Layer‐by ‐Layer Assembled Upconversion and Gold Nanoparticles
16:20 16:40 O‐14 Kevin Wylie and Milan Marić, McGill University Self‐Assembly of Gradient Copolymers Synthesized in Semi‐Batch Mode
18h30 : Dinner / Souper
Wednesday August 10, 2016 / Mercredi 10 août 2016
Theme: Polymer synthesis and modification
Thème : Synthèse et modification des polymères
Chairperson / Président : TBA
9:00 10:00 NOVA Keynote Lecture
Keynote Lecturer / Conférencier plénier : Craig J. Hawker, University of California Santa Barbara Doing New Things with Old Tricks ‐ Synthesis of Precision Materials
10:00 10:20 Pause / Break
10:20 10:40 O‐15 Tyler J. Cuthbert, Joshua Jadischke, Paul J. Ragogna and Elizabeth R. Gillies, Western University Polyphosphonium Containing Self‐Healing Materials: Synthesis, Characterization, and Healing
10:40 11:00 O‐16 Josée Brisson, Adrien Faye and Jacob Dion‐Gagné, Université Laval Polyethersulfone‐Based Copolymers: Flexible Comb Copolymer Synthesis for Fundamental Studies: From Crystallization to Membrane Science
11:00 11:20 O‐17 Amir Rabiee Kenaree and Joe B. Gilroy, Western University Synthesis and Characterization of Highly‐Metallized Phosphonium‐Based Polyelectrolytes and Their Applications in Material Science
11:20 11:40 O‐18 Michael W. Bodley, Brian M. Molloy, Kyle Ozols and J. Scott Parent, Queen’s University Controlling the Dynamics and Yields of Peroxide‐Initiated Polymer Modifications Using Functional Nitroxyls
11:40 13:00 Lunch / Dîner
Theme: Spectroscopy and molecular simulationThème : Spectroscopie et simulation moléculaire Chairperson / Président : TBA
13:00 13:30 I‐4 Invited Speaker / Conférencier invité : Phillip Y.K. Choi, University of Alberta Molecular Dynamics Study of Diffusion in Polymers
13:30 13:50 O‐19 Remi Casier, Jean Duhamel and Mario Gauthier, University of Waterloo Probing Interparticle Polymer Diffusion in Latex Films Using Pyrene Excimer Fluorescence
13:50 14:10 O‐20 Shimiao Zhang and Li Xi, McMaster University Precursor Effects on the Structure and Properties of Polymer Networks Synthesized Using Molecular Dynamics
14:10 14:30 O‐21 Justin Raimbault, Remi Casier, Hunter Little and Jean Duhamel, University of Waterloo Probing Intramacromolecular Forces by Pyrene Excimer Fluorescence
14:30 14:50 Pause / Break
14:50 16:30 SESSION D’AFFICHES / POSTER SESSION
16:30 17:00 HPF Meeting / Réunion du Colloque canadien sur les polymères
18h30 : Banquet / Banquet
Thursday August 11, 2016 / Jeudi 11 août 2016Theme: Biopolymers / Thème : Biopolymères Chairperson / Président : TBA
9:00 9:20 O‐22 Michael Landry, Mark Cronin‐Golomb and Christopher J. Barrett, McGill University Azobenzene‐Modified Silk Gels for Two‐Photon Light Induced Surface Patterning
9:20 9:40 O‐23 Lu Li and Jean Duhamel, University of Waterloo Conformation of Amylose in DMSO Probed by Pyrene Excimer Fluorescence
9:40 10:00 O‐24 Zijie Wang, Yu Wang and Guojun Liu, Queen’s University Rapid and Efficient Separation of Oil from Oil‐in‐Water Emulsions Using a Janus Cotton Fabric
10:00 10:20 Pause / Break
10:20 10:40 O‐25 Ryan C. Amos and Mario Gauthier, University of Waterloo Modification of Cooked Waxy Corn Starch with Alkenyl Succinic Anhydrides
10:40 11:00 O‐26 Morgan Lehtinen, Zijie Wang, Claudia Grozea and Guojun Liu, Queen’s University Water Based Approach to Asymmetric Cotton Fabric for Oil Separation from Emulsions
11:00 11:20 O‐27 Farhad Farnia, Weizheng Fan, Yves Dory and Yue Zhao, Université de Sherbrooke Cellulose Nanocrystals Made CO2‐Responsive by Polymer Grafting
11:30 13:00 Lunch / Dîner
List of Posters / Liste des Affiches
P1. Mosa Alsehli and Mario Gauthier, University of Waterloo, Arborescent Polypeptides Based on Poly(γ‐Benzyl L‐Glutamate) for Drug Delivery Applications
P2. So Young An and Jung Kwon Oh, Concordia University, Development of Self‐Healing Polymeric Networks Crosslinked by Dynamic Linkages
P3. Lemuel Tong, Jothirmayanantham Pichaandi, Loryn Arnett, Alexandre Bouzekri, Olga Ornatsky, Vladimir Baranov and Mitchell A. Winnik, University of Toronto, Synthesis and Surface Modification of Lanthanide (NaLnF4) Nanoparticles for High‐Sensitivity Mass Cytometry Bioassays
P4. Abdullah Basalem and Jean Duhamel, University of Waterloo, Probing the Interactions Between Pyrene‐Labeled Gemini Surfactants and Non‐Gemini Surfactants by Fluorescence
P5. Michael W. Bodley and J. Scott Parent, Queen's University, AOTEMPO‐Mediated Synthesis of Polypropylene‐Based Thermoplastic Vulcanizates
P6. Robert Claridge and Derek Schipper, University of Waterloo, Controlled Oxidation of Thiazole Containing Conjugated Polymers
P7. Joanne Fernandez, Nicole Tratnik and Mario Gauthier, University of Waterloo, Atom Transfer Radical Polymerization (ATRP) Grafting of Starch Nanoparticles with Sodium Acrylate
P8. Jacob Dion Gagné, Adrien Faye and Josée Brisson, Université Laval, Synthesis and Post Functionalization of Polyetherethersulfone‐Allyl Copolymers for Applications in Fuel‐Cell Membranes
P9. M. Thomas Gambles, Bo Fan and Elizabeth R. Gillies, Western University, Polyglyoxylate Nano‐ and Micro‐Particles for Triggered Drug Release
P10. Kiarash Gholami, Solmaz Pirouz and Jean Duhamel, University of Waterloo, Associations Between EP Copolymers in Base Oils Probed by Fluorescence
P11. Victoria Hisko, Jean Duhamel and Mario Gauthier, University of Waterloo, Fluorescently Labelled Latex Particles to Monitor Film Formation
P12. Arman Moini Jazani and Jung Kwon (John) Oh, Concordia University, Dual Location Dual Reduction and pH‐Responsive Degradable Block Copolymer Micelles for Enhanced Cellular Uptake and Drug Controlled Release
P13. Sungmin Jung, Dhamodaran Arunbabu and Jung Kwon Oh, Concordia University, Reversible Polymer Networks Composed of Polymethacrylate with Maleimide and Furan Groups in Response to Thermal Stimuli for Self‐Healing Materials
P14. Melinda Guo, Sohyoung Her, Rachel Keunen, Shengmiao Zhang, Christine Allen, Mitchell A. Winnik, University of Toronto, Rod‐Like Cellulose Nanostructures for Delivery of Radionuclides to Tumours
P15. Damin Kim, Jean Duhamel, Ryan Amos and Mario Gauthier, University of Waterloo, Characterization of Hydrophobically Modified Starch NanoParticles by Pyrene Fluorescence
P16. Nicholas Lanigan, Abdeljalil Assoud and Xiaosong Wang, University of Waterloo, Bulk Supramolecular Polymer from an Iron Acyl Piano Stool Complex
P17. Kyle Ozols and J. Scott Parent, Queen's University, Polypropylene Thermosets by VBTEMPO‐Mediated Peroxide Vulcanization
P18. Pierre‐Olivier Robitaille, Mounir Jaidann, Hakima Abou‐Rachid and Josée Brisson, Université Laval, Predicting Optical Properties of Energetic Materials Using DFT
P19. Frédéric‐Guillaume Rollet, Jaana Vapaavuori, Christopher J. Barrett, McGill University, Preparation and Binding Properties of Azobenzene Dyes in Soft‐Bonded Azo‐polymer Complexes
P20. Janine Thoma and Jean Duhamel, University of Waterloo, Probing the Conformations of Polymeric Bottle Brushes in Solution by Pyrene Excimer Formation
P21. Liying Wang, Deepak Vishnu Dharmangadan, Qiuying Zhang and Mario Gauthier, University of Waterloo, Synthesis of Cleavable Amphiphilic Block Copolymers
P22. Aklilu Worku and Mario Gauthier, University of Waterloo, Complex Arborescent Copolymer Architectures by Self‐Assembly
P23. Wangchuan Xiao, Puzhen Li and Jung Kwon Oh, Concordia University, In Situ Synthesis of Colloidal‐Stable Fe3O4 Nanoparticles Coated with Multidentate Block Copolymer for MRI Contrast Agents
P24. Qing Yu, Gerald Guerin, Ian Manners and Mitchell A. Winnik, University of Toronto, Investigating the Dissolution Mechanism in Self‐Seeding of PFS Block Copolymer Micelles
P25. Qian (Jasmine) Zhang, Lu Li and Jean Duhamel, University of Waterloo, Study of the Interactions of Pyrene‐Labeled SNPs with Sodium Dodecyl Sulfate (SDS)
P26. Guangyao Zhao, Jianbo Tan and Mitchell A. Winnik, University of Toronto, Lanthanide‐Containing PMMA Microspheres for Bead‐Based Assays on Mass Cytometry
P27. Hang (Joey) Zhou, Yijie Lu, Meng Zhang, Gerald Guerin, Ian Manners and Mitchell A. Winnik, University of Toronto, Approaches to the Formation of Nanofibrillar Hydrogels Based on Uniform PFS Rod‐Like Micelles
INVITED CONFERENCES / CONFÉRENCES INVITÉES
ML-MSRD strategy for block copolymer micelles for accelerated drug release and cancer therapy
Jung Kwon (John) Oh, PhD Department of Chemistry and Biochemistry, Concordia University, Montreal, QC, H4B 1R6
Well-defined amphiphilic block copolymers and their self-assembled nanostructures designed with stimuli-responsive degradation (SRD) have been extensively explored as a choice of promising nanocarriers for pharmaceutical science and cancer therapy. SRD involves the incorporation of dynamic covalent linkages, which can be later cleaved in response to external stimuli, preferably cellular components. Thus, SRD-exhibiting nanocarriers, which are stable under physiological conditions during blood circulation, can be dissociated in a controlled fashion as cellular components provide the appropriate stimuli to trigger biodegradation in microenvironments of tumors and inside cancer cells. Numerous methods have been reported for the synthesis of SRD-exhibiting block copolymers and their self-assembled nanostructures. However, most conventional methods incorporate cleavable linkages of different densities positioned at single locations, such as micellar core or core/corona interfaces (Single location SRD). Our research group has recently focused on an effective SRD strategy that centers on the development of new intracellular nanocarriers having multiple stimuli-responsive cleavable linkages at multiple locations, as in the micellar core, in the interlayered corona, and at the interface between the hydrophobic core and corona (denoted as multi-location multiple SRD strategy. This called ML-MSRD strategy dramatically increases versatility since responses to each stimulus can independently and precisely regulate release of encapsulated biomolecules at several locations. Further, the strategy enables the investigation of structure-property relationship between morphological variance and stimuli-responsive degradation. Ultimately, the results enable the optimization of degradable micelles offering enhanced release inside diseased cells, particularly targeted cancer cells.
Single-location SRD
Y Y
Y Y
XX
XX X
X
X
XY
ML-MSRD
X, Y: cleavable linkage (disulfide (SS), acid-labile, or photo-cleavable group
I-1
Carbon-Rich 2D Polymers: Toward Non-Graphene Semiconducting Materials
Jean-Francois Morin1, Samuel Caron1 and Charles-Olivier Gilbert1
Département de Chimie and Centre de Recherche sur les Matériaux Avancés (CERMA), 1045 Ave de la Médecine, Université Laval, Quebec City, Quebec, Canada G1V0A6
2D carbon-based and inorganic materials have been the subjects of intense research in the past ten years owing to their outstanding electronic properties. Among them, graphene is the material that has been the most studied as it exhibits very high charge carrier mobility values (up to 104 cm2/V�s) in both positive and negative regimes. Graphene is thus an excellent candidate for numbers of next-generation electronic applications. However, graphene has no bandgap (semi-metal) in its pure form, which limit its use in electronic devices, especially as active component in transistors. Introduction of structural defaults and chemical doping can lead to the creation of a bandgap, but these strategies are difficult to implement and suffer from poor reproducibility. Hence, the development of new bottom-up methods for the preparation of non-graphenic, 2D semiconducting materials represents a promising avenue for electronic applications.
In this seminar, we will present our first attempts to prepare 2D semiconducting materials at the air-water interface. Two strategies that we are pursuing will be presented. First, we will present our approach based on the self-assembly and light-promoted topochemical polymerization of amphiphilic poly(1,3-butadiyne)s at the air-water interface to form 2D polydiacetylenes (Figure 1). Then, we will show how modified, amphiphilic fullerene-C60 can be used as a monomer for surface polymerization to yield 2D polyfullerenes. In both cases, synthesis, monolayer formation and 2D polymers characterization will be discussed.
Figure 1. Synthesis of 2D polydiacetylene at the air-water interface.
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R' = Hydrophilic chain
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I-2
Reaction Development for the Synthesis of Conjugated Polymers
Derek J Schipper
Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, ON N2L 3G1, Canada
Conjugated polymers are quickly becoming indispensable for technologies such as photovoltaics, light emitting diodes and field-effect transistors. Therefore, efficient assembly of these materials is an important goal. Advancing synthetic strategies provide a direct way to both streamline synthesis and render new polymer architectures synthetically accessible. This talk will discuss our recent efforts developing a C-H bond functionalization and dehydration polymerization strategies to access novel, heterocycle-containing conjugated polymers.
I-3
Molecular Dynamics Study of Diffusion in Polymers
Phillip Choi Department of Chemical and Materials Engineering
University of Alberta Edmonton, Alberta, CANADA
T6G 1H9 Email: phillip.choi@ualberta.ca
Abstract
With ever-increasing demand on the performance of materials exhibiting unique functional properties, design of such materials and the associated manufacturing processes has become fairly sophisticated. This, in turn, requires a deeper understanding of the corresponding structure-processing-property relationships. And in some cases, it is highly desirable to have molecular level of understanding. With advances in computer technology and developments in molecular simulation methods, complex molecular systems and physical phenomena of engineering importance can be investigated with ease. Such simulation provides an effective means to determine how molecular structure and atomic-level interactions determine macroscopic properties of materials of interest as well as how they response to the imposed processing conditions. In this presentation, I will present some basic principles and techniques used in molecular simulation and research problems in the area of diffusion in polymers that my group has embarked on over the past decade using such techniques. In one example, I will demonstrate how molecular simulation help design a biopolymer that has the potential to be used for food packaging applications.
I-4
CONFERENCES / CONFÉRENCES
Some new Opto-Reversible Polymers Inspired by Nature: New Light on the Nano-Bio Interface.
Christopher J. Barrett, Michael Landry, Frederic Rollet, & Daniel de Biasio.
McGill University & the Montreal Neurological Institute.
Abstract: Developing new materials for two-way communication at the bio-interface
represents an emerging interdisciplinary research challenge, and brain-machine interfaces in
particular hold exciting promise, with recent breakthroughs achieved from various labs around
the world towards localized neuro-sensing and signaling. Key to many of these collaborative
interface projects is developing new materials which are compatible with biological tissue, and
sensitive to fast and subtle signals, yet can also interface with traditional technologies for
readout and interpretation. Some promising new directions in bio-materials for bio-surfaces
have turned to natural materials and processes for inspiration, specifically in using light as
opposed to electrical signals, and in using softer bio-compatible materials for implants in place
of hard metal electrodes.
At McGill Chemistry, in collaboration with Montreal’s Neurological Hospital, we
have designed some polymers based on molecular opto-switches as artificial mimics of the
retinal photo-switch proteins that enable human vision, and thus a possible direct interface
between cells and optical technologies. These ‘artificial vision’ molecules based on azobenzene
structures respond physically when irradiated by changing shape, to permit visible to be
converted directly and reversibly to mechanical work. When applied as bio-coatings, reversible
changes in surface energy are also inducible as a result, for a variety of reversible surface
switching applications via light, which we have demonstrated to be able to control and guide
adjacent cells. Tuning the materials and surfaces to match various cells and tissues can be
achieved via multi-layering of host polyelectrolytes, where relevant properties can be fine-
tuned with deposition parameters. High throughput screening of surface properties can be
achieved with multi-dimensional combinatorial surfaces, where the equivalent of many
hundreds or thousands of discrete surface physic-chemical properties can be combined on a
single film for efficient testing.
O-1
Highly flexible free-standing conductive polypyrrole membrane Jifu Mao1, Hyun Jin Park1,2, Yongliang Wang1,2, Mahmoud Rouabhia2, Ze Zhang1
1.Centre de recherche du CHU de Québec, Département de chirurgie, Faculté de médecine,
Université Laval, Québec (QC), Canada
2.Groupe de Recherche en Écologie Buccale, Faculté de Médecine Dentaire, Université Laval,
Québec (QC), Canada
Because of their highly conjugated chemical structure, intrinsically conductive polymers such as
polypyrrole (PPy) are rigid and brittle, and are often used in form of coating or dispersion. There
has been no report of any highly flexible and free standing membrane of intrinsically conductive
polymers. In this work, a highly flexible free standing PPy membrane was fabricated by an
improved interfacial polymerization3. The specimens were characterized by scanning electron
microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron
spectroscopy (XPS), four-point probe and tensile property measurement. To test the cytotoxicity
of the membrane, human skin fibroblasts were seeded on both sides of the membrane and
cultured for 48 hours. The large-sized PPy membrane is about 0.3 mm in thickness and has a
surface conductivity of 1.0 S/cm. The membrane has asymmetric surface structures showing
bubble-like morphology on one side and nano-tubular morphology on the other. Surprisingly, this
membrane showed outstandingly flexibility with little permanent deformation after repeated 180
degree bending. FTIR revealed the similar chemical composition of the two sides, which was
confirmed by XPS results. Analysis of stress-strain curve indicated a stress at break of 94 kPa
with 6% of strain for the flexible PPy membrane. It demonstrated that this PPy membrane is
superior in cell attachment compared to cell culture glass. The number of cells of the
experimental groups increased significantly with culture time, showing that the membrane was
not cytotoxic and supported fibroblast growth on both sides. The absence of cytotoxicity, the
conductivity, the highly flexibility and the ECM-like morphology may find this PPy membrane
useful in industrial and biomedical applications.
Références : [1] Bendrea A-D, Cianga L, and Cianga I. Journal of biomaterials applications 2011;26(1):3-84.
[2] Qi, Guijin, Zhenglong Wu, and Huiliang Wang. Journal of Materials Chemistry C. 2013; 42: 7102-
7110.
[3] Zhao Cui‐E, Jiansheng Wu, Staffan Kjelleberg, Joachim Say Chey Loo, and Qichun Zhang. Small.
2015;11: 3440-3443.
O-2
Membrane Binding and Oligomer Formation by the Calcium-Dependent Lipopeptide Antibiotic A54145:
A Quantitative Study with Pyrene Excimer Fluorescence
T. Zhang, S. Taylor*, M. Palmer*, J. Duhamel* Department of Chemistry, Institute for Polymer Research, University of Waterloo,
Waterloo, ON N2L 3G1, Canada
A54145 is a lipopeptide antibiotic related to daptomycin that permeabilizes bacterial cell membranes. Its action requires both calcium and phosphatidylglycerol in the target membrane. We here probed the interaction of A54145 with model membranes composed of dimyristoylphosphatidylcholine (PC) and dimyristoylphosphatidylglycerol (PG), using the fluorescence of a pyrene-labeled derivative (Py-A54145). Qualitative analysis of the steady-state and time-resolved fluorescence data demonstrated the binding of Py-A54145 to and its aggregate formation in the PC/PG liposomes. Quantitative information about the molar fractions of Py-A54145 in various states with respect to membrane binding and oligomer formation were obtained by fitting globally the time-resolved monomer and excimer fluorescence decays of Py-A54145 according to the Model Free Analysis (MFA). Binding of Py-A54145 to PC/PG membranes at Ca2+ concentrations as low as 0.15 mM could be clearly identified from the large increase in the fluorescence intensity and average decay time of the pyrene monomer as well as the concomitant appearance of excimer fluorescence. Quantitative analysis of the fluorescence decays indicated that Py-A54145 bound as oligomers to the DMPC/DMPG liposomes. While binding was virtually complete at 1 mM Ca2+, the membrane-bound peptide displayed a distinct second transition in its fluorescence properties when the calcium concentration was raised further. This transition was consistent with the formation of larger peptide oligomers with multiple subunits. Our findings suggest that membrane binding of A54145 and formation of the oligomeric membrane defect that is at the origin of its antibacterial activity occur in discrete, successive steps that might involve the binding of several calcium ions and the rearrangement of peptide oligomers in the PC/PG membrane.
O-3
Formation of Enzyme and Oxidation Dual-sensitive Nanocarriers via Thiol-ene Click Reaction
for Efficient Targeted and Controlled Anticancer Drug Delivery
Sung Hwa Hong and Jung Kwon Oh
Department of Chemistry and Biochemistry, Concordia University
Abstract
Polymer-based drug delivery systems are a promising platform for tumor-targeting delivery
applications. Polymeric nanocarriers are able to encapsulate anticancer therapeutics and to
deliver the drugs to targeted tumor sites upon intravenous administration. The therapeutic
efficacy is maximized by controlling their pharmacokinetics in the blood stream and
biodistribution profile in tumor tissues. Followed by the internalization in tumor cells through
endocytosis, the encapsulated drugs are released in a rapid and controlled fashion. A promising
approach to enhanced and controlled release is stimuli-responsive degradation (SRD) that
involves the incorporation of dynamic covalent linkages, which can be cleaved in response to
external stimuli. Colloidally stable nanocarriers under physiological condition can be dissociated
in response to appropriate stimuli in the intracellular environment. In particular, enzyme-
responsive nanocarriers are showing promise in nanocarrier development, since covalent ester
linkages can be cleaved in the presence of esterase enzymes. Our research group has explored the
development of new methods to synthesize dual or multi stimuli-responsive degradable systems
coupled with enzyme-responsive degradation. As a proof-of-concept approach, we have
synthesized a novel polyester composing of both ester and sulfide linkages by a click-type thiol-
ene Michael addition reaction. In the presence of biocompatible stabilizer, the polyester has
formed colloidally-stable nanoparticles of hydrophobic polyester cores, which are physically-
stabilized with hydrophilic polymers (similar to oil-in water emulsion). The ester linkage can be
cleaved in the presence of an esterase and the sulfides can be converted to the corresponding
hydrophilic sulfones in response to oxidative reaction in the body. These dual responses result in
either polarity change or main chain degradation, leading to enhanced release of encapsulated
anticancer drugs in targeted tumor tissues. Our preliminary results indicate that our new strategy
opens up new research area and offers versatility in cancer therapy.
Figure 1. Schematic representation of drug delivery system by passive targeting
O-4
Remoldable Azobenzene Liquid Crystalline Networks Displaying Light-Driven Motions
Xili Lu1,2, Hesheng Xia2, Yue Zhao1* 1. Département de chimie, Université de Sherbrooke, Sherbrooke, Québec, J1K 2R1,
Canada. 2. State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute,
Sichuan University, Chengdu 610065, China.
Liquid crystalline elastomer based mechanical actuators are attracting broad and increasing interest in recent years because of their potential applications in environmentally activated motors, sensors, artificial muscles, microrobotics, and energy generators. These kinds of actuators can exhibit reversible shape changes (e.g., bending, contraction, extension, curling, and rotation) in response to environmental stimuli, such as light, moisture and thermal energy. However, it remains a challenge to endow these actuators with biomimetic ability to convert environmental stimuli into self-propelling and continuous motions. Here, we describe the design, synthesis and fabrication of remoldable azobenzene liquid crystalline networks based intelligent devices, such as spring-like motors, ring-like motors, hoists and grippers, which can convert light energy into sophisticated, tunable and/or continuous motions at the macroscopic scale.
O-5
Stable Water-Dispersible Air Nanobubbles Encapsulated with ABC Triblock Copolymer
bearing Fluorinated Block with Super-Low Surface Energy
Yu Wang,1 Guojun Liu,1*, Heng Hu,1 Terry Yantian Li,2 Amer M. Johri,3 Xiaoyu Li,1 and Jian
Wang1
1: Department of Chemistry, Queen’s University, 90 Bader Lane, Kingston, Ontario, Canada K7L
3N6 2: Department of Biomedical and Molecular Sciences, Queen’s University, 18 Stuart Street,
Kingston, Ontario, Canada K7L 3N6. 3: Department of Medicine, Queen’s University, Kingston
General Hospital FAPC 3, 76 Stuart Street, Kingston, Ontario, Canada K7L 3N6
Abstract. Air nanobubbles, due to their small sizes and thus ability to permeate the capillary
networks of organs and to reach tumors, may expand the applications of their micrometer-sized
counterparts (microbubbles) in diagnostic ultrasonography and find new applications in
ultrasound-regulated drug delivery. However, there had been no reports on the preparation of
stable air nanobubbles before our recent publication. We report in this talk the preparation of
stable encapsulated air nanobubbles in water by dispersing into water of nanocapsules bearing a
fluorinated internal lining. Water is not able to enter cavities of the capsules because of the high
hydrophobicity of the capsular walls. These bubbles, like microbubbles, effectively reflected
ultrasound. More importantly, the nanobubbles have a life time under ultrasonication that was
~100 times longer than that of a commercial microbubble sample that is widely used clinically. In
addition to discussing the preparation and properties of these nanobubbles, we will also provide
theoretical justification for this unprecedented stability.
O-6
Complex Thermo-responsive Behaviors of Select Block Copolymers
Yong-Guang Jia and X. X. Zhu* Departement de Chimie, Universite de Montreal,
C.P. 6128, Succursale Centre-ville, Montreal, QC, H3C 3J7, Canada
Some synthetic block copolymers manifested complex thermos-responsive behaviors in aqueous solutions. We used RAFT polymerization to prepare mutli-block copolymers based on mono- and di-substituted N-alkylacrylamides and have found that the aqueous solutions of poly(N-n-propylacrylamide)-b-poly(N,N-ethylmethylacrylamide) (PnPA-b-PEMA) change from a transparent solution to a cloudy mixture at the first phase transition temperature, and then to a clear solution and finally to a turbid mixture at the second transition temperature. To understand such an unusual and complex thermoresponsive behavior, a series of experiments were carried out to map out a phase diagram for the polymer solutions in water. Results from dynamic light scattering and atomic force microscopy help to assign the first cloud point to a transition from unimers to micellar clusters. Further rise in temperature leads to restructuring and dissociation of these loose micellar clusters into smaller micelles, resulting in an optically clear solution. A second cloud point appears when the micelles start to aggregate. The PnPA block is longer than the PEMA block, and the hydrogen bonding between the PnPA and PEMA blocks is the determining forces for the formation of micellar clusters. The thermoresponsive behavior depends on the polymer concentration and is reversible with a certain hysteresis. A concentration-temperature phase diagram was drawn up for N-substituted polyacrylamides, providing guidelines towards the rational design of thermoresponsive copolymers showing two or multiple responsive temperatures.
Related References: Y.G. Jia, X.X. Zhu, Polym. Chem., 5, 4358 (2014). Y.G. Jia, X.X. Zhu, Langmuir, 30, 11770 (2014). Y.G. Jia, X.X. Zhu, Chem. Mater., 27, 387 (2015). Y.G. Jia, X. X. Zhu, ACS Appl. Mater. Interfaces, 7, 24649 (2015). Y.G. Jia, X. X. Zhu, RSC Advances, 6, 23033 (2016).
O-7
Synthesis, Characterization, and Switchable Thin-Film Conductivity of 6-Oxoverdazyl Radical Polymers Prepared via ROMP
Joseph A. Paquette,a,b Sabastine Ezugwu,b,c Giovanni Fanchini,a,b,c Joe B. Gilroy*a,b
aDepartment of Chemistry, The University of Western Ontario, London, Ontario, N6A 5B7, Canada bThe Centre for Advanced Materials and Biomaterials Research (CAMBR), The University of Western Ontario,
London, Ontario, N6A 5B7, Canada cDepartment of Physics and Astronomy, The University of Western Ontario, London, Ontario, N6A 3K7, Canada
The ability to exploit the unique properties of small molecules within polymers can improve upon
existing technologies by taking advantage of the processability, robustness, and flexibility
associated with polymers.1 One particularly interesting class of functional polymers incorporates
air- and moisture-stable organic radicals. The majority of research focused on these materials has
been aimed toward the production of electrode materials for batteries, although they have other
applications as (co)catalysts for the oxidation of alcohols, solid-state conductive materials, and the
functional components of memory architectures, for example.2 Our research focuses on the
incorporation of 6-oxoverdazyl radicals into polymer scaffolds. Redox-active 6-oxoverdazyl
radicals can be synthetically modified at the 1, 3, and 5 positions in order to tailor their electronic
properties, introduce a variety of polymerizable groups, and alter solubility,3 which are essential
tools for the design of functional materials.4 During this presentation polymers containing redox-
active 6-oxoverdazyl radicals using ring-opening metathesis polymerization (ROMP), including
their synthesis, characterization, and switchable thin-film conductivity, will be discussed.
References
1. G. Meller, T. Grasser, Organic Electronics; Springer: Berlin, 2010.
2. E. P. Tomlinson, M. E. Hay, B. W. Boudouris Macromolecules, 2014, 47, 6145–6158.
3. J. T. Price, J. A. Paquette, C. S. Harrison, R. Bauld, G. Fanchini, J. B. Gilroy. Polym. Chem. 2014, 5,
5223–5226.
4. J.A. Paquette, S. Ezugwu, V. Yadav, G. Fanchini, J.B. Gilroy J. Polym. Sci., Part A: Polym. Chem. 2016,
54, 1803−1813.
O-8
“Click” Functionalization of Conjugated Polymers by Strain-Promoted Cycloaddition
Vladimir Kardelis, Ryan C. Chadwick, Kelvin Li, and Alex Adronov Department of Chemistry, McMaster University
Post-polymerization functionalization of polymers is a well-known technique for modifying
polymer structure after it has been formed. It has been used to prepare block, graft, star, and
hyperbranched polymers. However, post-polymerization functionalization of a π-conjugated
polymer, in a manner that modifies is conjugated backbone, poses a number of challenges. We
have recently described the preparation of a conjugated polyphenyl-co-dibenzocyclooctyne Schiff-
base polymer, prepared via polycondensation of dibenzocyclooctyne bisamine (DIBO-(NH2)2)
with bis(hexadecyloxy)phenyldialdehyde. The resulting polymer, having a high molecular weight
(Mn > 30 kDa, Mw > 60 kDa), undergoes efficient strain-promoted alkyne-azide cycloaddition
reactions with a variety of azides. This enables quantitative modification of each repeat unit within
the polymer backbone and the rapid synthesis of a conjugated polymer library having widely
different substituents, but a constant degree of polymerization (DP). Kinetic studies showed a
second order reaction rate constant that is consistent with monomeric dibenzocyclooctynes.
Grafting with azide-terminated polystyrene and polyethylene glycol monomethyl ether chains of
varying molecular weight resulted in the efficient syntheses of a series of graft copolymers with a
conjugated backbone and maximal graft density. This presentation will highlight the synthesis and
properties of this new class of polymers.
O-9
Title: Semiconducting SWCNT: from materials to thin film transistors
Name: Zhao Li, Patrick R. L. Malenfant, Jianfu Ding, Jacques Lefebvre Security and Disruptive Technologies Portfolio, National Research Council Canada,
Ottawa, Ontario, Canada
Significant progress has been made in the last ten years on the topic of separating semiconducting (SC) from metallic single walled carbon nanotubes (SWCNTs). Techniques such as conjugated polymer extraction (CPE), chromatography, and density gradient ultracentrifugation (DGU) have been shown to be particularly effective at SC-SWCNT enrichment. As a result, the fabrication of thin film transistors comprising enriched SC-SWCNTs has been undertaken by several research teams in hopes of obtaining higher performance printed logic, display drivers and novel sensors. We have compared DGU, chromatography and CPE and found the later to have many positive attributes such as a competitive cost model, scalability and product quality.
Our recent progress and commercialization (IsoSol-S100TM) of the CPE method to produce high purity SC-SWCNTs dispersed in organic solvents will be presented. We also developed a novel methods using Raman mapping to quantify SC-SWCNT purity beyond 99%. After fine-tuning the substrate surfaces and SWCNT/polymer solution property, uniform and high density tube network was obtained. Thin film transistor (TFT) based on SC-SWCNT as active channels demonstrate both high mobility and on/off ratio. Application of this kind of solution as ink for inkjet printing will also be addressed.
Ref: 1. Zhao Li , Jianfu Ding, Paul Finnie, Jacques Lefebvre, Fuyong Cheng, Christopher T.
Kingston, and Patrick R. L. Malenfant, Nano Research, 2015, 8(7), 2179.2. Zhao Li , Jianfu Ding, Jacques Lefebvre, Patrick R.L. Malenfant, Organic Electronics,
2015, 26, 15.3. Jianfu Ding, Zhao Li, Jacques Lefebvre, Fuyong Cheng, Girjesh Dubey, Shan Zou, Paul
Finnie, Amy Hrdina, Ludmila Scoles, Gregory P. Lopinski, Christopher T. Kingston, BenoitSimard and Patrick R. L. Malenfant, Nanoscale, 2014, 6, 2328.
Biography
Zhao Li has completed his PhD in 2000 from Chinese Academy of Sciences, and then 3 years postdoctoral studies in Calgary University in Canada. He joined Canadian Research Council in 2003 and now is a Research Council Officer. His researched focused on cnojugated polymer synthesis and characterization, organic photovoltaics, carbon nanomaterials and its application in thin film transistors. He has published more than 35 papers in reputed journals.
Presenting author details Full name: Zhao Li Contact number: 613-990-0064 Email: Zhao.Li@nrc.gc.ca Category: (Oral presentation)
O-10
Development of Green Plasticizers: A Case Study
Hanno Erythropel,1 Roya Jamarani,1 Richard Leask,1 Milan Marić1 and Jim Nicell2
1Department of Chemical Engineering, McGill University, Montreal, QC, Canada H3A 0C5 2Department of Civil Engineering and Applied Mechanics, McGill University, Montreal, QC Canada
H3A 0C3
ABSTRACT: The development of green alternative plasticizers at McGill has been an on-going collaborative effort, spanning from identification of toxic persistent metabolites in local water supplies, followed by degradation pathways and finally reverse engineering of the plasticizer structure to impart innocuous or short-lived metabolites upon disposal. The next phase consisted of ensuring that the plasticizer performed mechanically as well or better to traditional plasticizers like di(2-ethylhexyl phthalate) (DEHP) for poly(vinyl chloride) (PVC), which has since been banned in many jurisdictions due to its potential adverse health effects like endrocrine disruption. We have mainly used a succinate/maleate/fumarate motif to mimic the structure of DEHP and added n-alkyl chains to provide the lubricity necessary. Properties such as glass transition temperature (Tg) and tensile strength were found to be comparable to DEHP plasticized blends at similar loadings. Further, the succinate family was particularly effective and time-temperature superposition suggested similar rheological properties during processing. More recently, we have started to synthesize succinate-based plasticizers derived from sustainable sources to make the plasticizer greener. The various challenges and collaborative efforts from each of these steps will be highlighted and future perspectives for industrial scale-up will be addressed.
O-11
Dianhydride architecture effects on thermal and mechanical properties of polyimides Ahmad Raza Ashraf1,2, Leonardo C. Simon1, Zareen Akhter2
1. Department of Chemical Engineering, University of Waterloo, Waterloo, Canada2. Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan
Abstract: Aromatic polyimides exhibit favorable combination of properties compared to other polymers: outstanding thermal stability, excellent mechanical strength, high glass transition temperature and superior chemical, radiation and fire resistance. Therefore these polymers have niche applications in aerospace, automotive and microelectronic industries as films, adhesives, sealants, coatings, insulators etc. The exceptional properties of polyimides depend on chemical structure and intra- or inter-chain interactions. They can be synthesized via two step route: diamine is condensed with dianhydride at room temperature to yield polyamic acid which is then cyclodehydrated into corresponding polyimide. In this study, effects of dianhydride architecture on thermal and mechanical properties of polyimides were investigated by reacting 4,4'-methylenedianiline (diamine) with three dianhydrides: 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA), oxydiphthalic anhydride (ODPA) and 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA).
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6FDA
It was observed (TGA graphic, left) that BTDA-based polyimide had the highest thermal stability while it was lowest for polyimide derived from 6FDA. However, 6FDA-based polyimide displayed higher glass transition temperature than BTDA and ODPA. Modulus followed the order: 6FDA ˃ BTDA ˃ ODPA (DMTA graphic, right).
BTDA ODPA 6FDA
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ght (
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a)
BTDA ODPA 6FDA
O-12
Spatial Organization and Optical Properties of Layer-by-Layer Assembled
Upconversion and Gold Nanoparticles
Jun Xiang, Xia Tong and Yue Zhao*
Département de chimie, Université de Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1
E-mail: yue.zhao@usherbrooke.ca
Abstract
Multilayers of NaYF4:18%Yb,0.5%Tm@NaYF4 upconversion nanoparticles (UCNP), up to 10
UCNP/polyelectrolyte bilayers, were first prepared using the layer-by-layer (LBL) method. The
assembled thin film of UCNP was found to display good stability of upconversion luminescence
(UCL). Then LBL assembled films comprising four UCNP/polyelectrolyte bilayers and four gold
nanoparticles (AuNP)/polyelectrolyte bilayers were prepared by adjusting their deposition order to
give rise to three different spatial organizations of the two types of nanoparticles. The UV-vis-NIR
extinction spectra and UCL emission spectra upon 980 nm excitation revealed that the spatial
organization determined by the sequence of deposition influences the interaction between UCNP
and AuNP and thus their optical properties. The alternating deposition of UCNP and AuNP layers
appears to be the best way to preserve their “individual” properties, as a result of reducing both the
agglomeration of AuNP and the scattering of the 980 nm excitation light that accounts for a
quenching effect on the UCL of UCNP. By contrast, with the same numbers of UCNP and AuNP
layers, successive deposition of UCNP followed by successive addition of AuNP results in more
agglomeration of AuNP leading to a broad SPR band in the NIR region and also the most
significant quenching of the UCL intensity of UCNP. This study demonstrates an easy and
effective method for preparing NIR-responsive and plasmonic hybrid thin films with the
possibility to tune their optical properties through spatially controlled organization of the
nanoparticles.
O-13
Self-Assembly of Gradient Copolymers Synthesized in Semi-Batch Mode
Kevin Wylie and Milan Maric
Department of Chemical Engineering, McGill University, Montreal, QC, Canada H3A 0G4 McGill Institute of Advanced Materials (MIAM), Centre for Self-Assembled Chemical Structures (CSACS), Centre du Recherche Sur les Systèmes Polymères et Composites à Haute Performance (CREPEC)
ABSTRACT: The effect of fuzzy interfaces on block copolymer self-assembly was studied via gradient copolymers (GCP) for application in maskless lithographic systems. Poly(styrene-grad-methyl methacrylate) (PS-grad-PMMA) were synthesized in semi-batch mode using nitroxide-mediated polymerization (NMP) with varied monomer injection protocols (Molecular weights (MN) ranged from 48 000 g mol-1 to 94 000 g mol-1 with dispersities (Đ) between 1.35 and 1.59). The GCPs were spun into thin films on substrates made neutral by (S-ran-MMA-ran-hydroxyethyl methacrylate) terpolymers and annealed at elevated temperature to produce vertically oriented microphase-separated domains. The GCPs were found to have similar domain spacing to those estimated for BCPs with identical MN and composition. However, GCPs synthesized with long injection times were found to exhibit very poor self-assembly attributed to their predicted random-copolymer-like middle sequence, which was attributed to the reduction of effective enthalpic interaction parameter.
Scheme 1: Poly(methyl methacrylate-grad-styrene) (P(MMA-grad-St)) copolymers on different P(MMA-St-HEMA) brushes to promote preferred orientation of cylinders and lamellae.
O-14
Polyphosphonium containing self-healing materials: Synthesis, Characterization, and Healing
Tyler J. Cuthbert#, Joshua Jadischke#, Paul J. Ragogna#, Elizabeth R. Gillies#,‡
#Department of Chemistry, The University of Western Ontario, London, ON Canada. ‡Department of Chemical and Biochemical Engineering, The University of Western Ontario, London, ON Canada.
The development of smart materials is a promising new field of material science involving the incorporation of functionality into synthetic products. Self-healing materials are able to heal both local and global damage autonomously with the goal of have a positive impact on the lifetime and applications of coatings and plastics.1 Self-healing materials have been focused on creating materials containing microcapsules,2 reversible Diels-Alder crosslinks,3 coordination chemistry,4 or ionic crosslinks5. Ionic crosslinking has mainly centered on ammonium-based polymers, and so far no phosphonium based healing polymer networks have been reported, other then fluidic supramolecular networks.6 Reversible addition fragmentation chain transfer (RAFT) polymerization of trialkyl phosphonium monomers to achieve high molecular weight polyphosphoniums with low dispersity are combined with polyacrylate to create an ionic cross-linked polymer network. We aim to understand the effects on the mechanical properties of the polymer network and its ability to heal by varying the alkyl chain length on the phosphonium substituent, as well as the Mn and dispersity of the polyphosphoniums. We have hypothesized that the polymer length will have an effect on the physical crosslinking and mobility of the components in the system, resulting in the ability to manipulate the mechanical characteristics of the network. Initial results have shown high mechanical strength for ionic cross-linked networks with the ability to heal very quickly in low concentrations of salt (0.1 M NaCl).
1) Bekas, D. G.; Tsirka, K.; Baltzis, D.; Paipetis, A. S. Compos. Part B Eng. 2016, 87, 92–119.2) White, S. R.; Sottos, N. R.; Geubelle, P. H.; Moore, J. S.; Kessler, M. R.; Sriram, S. R.;
Brown, E. N.; Viswanathan, S. Nature 2001, 409, 794–797.3) Bergman, S. D.; Wudl, F. J. Mater. Chem. 2008, 18, 41.4) Rao, Y.-L.; Chortos, A.; Pfattner, R.; Lissel, F.; Chiu, Y.-C.; Feig, V.; Xu, J.; Kurosawa, T.;
Gu, X.; Wang, C.; He, M.; Chung, J. W.; Bao, Z. J. Am. Chem. Soc. 2016, 138, 6020–6027.5) Reisch, A.; Roger, E.; Phoeung, T.; Antheaume, C.; Orthlieb, C.; Boulmedais, F.; Lavalle,
P.; Schlenoff, J. B.; Frisch, B.; Schaaf, P. Adv. Mater. 2014, 2547–2551.6) Wathier, M.; Grinstaff, M. W. J. Am. Chem. Soc. 2008, 130, 9648–9649.
R3P
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R = Ethyl or ButylR3P
RAFT polymerization
Cl Cl
Na
R3P
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NaCl
precipitation
O-15
Polyethersulfone-Based Copolymers : Flexible Comb Copolymer Synthesis for Fundamental
Studies: From Crystallization to Membrane Science
Josée Brisson, Adrien Faye and Jacob Dion-Gagné
Département de chimie, CERMA and CQMF, Faculté des sciences et de génie, Université Laval, Québec, Canada G1V 0A6
Poly(ethersulfones) possess outstanding thermal properties, but also suffer from various drawbacks, such
as low surface hydrophilicity, which favors biofouling, and high solubility in polar solvents at high
temperature, which limits its applications in fuel cells. Although obtained in their amorphous form after
melt processing, they can undergo solvent-induced crystallization, which contributes to aging.
Rigid-flexible copolymers based on polyethersulfones will be presented. The flexible moiety bears allyl
groups which can be modified post-polymerization to tailor the properties for specific applications. Such
changes have been made mostly by using the thiol-ene click reaction. Examples of changes in crystallinity,
hydrophilicity, glass transition temperature and ionic mobility will be used to illustrate the possibilities
that this approach offers.
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Poly(6EES-ran-4EEScb)-graft-R
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R =H, Cl, Br
SO3-
O-16
Synthesis and Characterization of Highly-Metallized Phosphonium-
Based Polyelectrolytes and Their Applications in Material Science
Amir Rabiee Kenaree and Joe B. Gilroy*
Department of Chemistry and the Centre for Advanced Materials and Biomaterials Research
(CAMBR), The University of Western Ontario, 1151 Richmond St. N., London, Ontario,
Canada, N6A 5B7.; E-mail: joe.gilroy@uwo.ca.
Abstract: Metal-containing polymers (MCPs) are processable materials that offer many unique
properties originating from the metals they incorporate. Depending on the type of metal and the
polymer structure, MCPs have been successfully used, for example, as magnetic, catalytic,
emissive, antimicrobial, redox-active, and preceramic materials.1 The emerging need for new
functional materials has motivated us to design and utilize novel phosphine-based templates for
the synthesis of highly-metallized polymers with different transition metal ratios (1). Thorough
characterization of the resulting materials confirmed their macromolecular nature and that the
metal-based properties were preserved. Thin film pyrolysis of the MCPs afforded novel crystalline
nanomaterials which were characterized by SEM, EDX spectroscopy, and powder XRD.2 In this
presentation, the synthesis and characterization of the MCPs and their conversion to metal-
containing nanomaterials will be discussed.
1 Whittell, G. R.; Hager, M. D.; Schubert U. S.; Manners, I. Nat. Mater. 2011, 10, 176-188. 2 (a) Rabiee Kenaree, A.; Berven, B.M.; Ragogna, P.J.; Gilroy, J.B. Chem. Commun. 2014, 50, 10714‒10717. (b) Rabiee Kenaree, A.; Gilroy, J.B. 2016, submitted.
SEM
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Fe/Ru = 3/0, 2/1, 1/2, 0/3
1 µm
n
1000 C
H2/N23h
M: Fe and/or Ru
1
O-17
Controlling the Dynamics and Yields of Peroxide-initiated Polymer Modifications using Functional Nitroxyls
Michael W. Bodley, Brian M. Molloy, Kyle Ozols and J. Scott Parent Department of Chemical Engineering
Queen’s University Kingston, Ontario, Canada.
Solvent-free chemical modification of polyolefins using radical chemistry is practiced widely to transform
inexpensive commodity polymers into value-added materials. Leading examples include the cross-
linking of ethylene-rich thermoplastics to yield thermosets with enhanced temperature stability, and the
degradation of propylene-rich materials to improve their rheological properties. Irrespective of their
application, these batch processes proceed through macroradicals that are generated by H-atom
transfer to peroxide-derived initiator fragments. As a result, their dynamics are controlled by the first-
order rate of peroxide thermolysis, and their yields are determined by the intrinsic reactivity of their
macroradical intermediates.
This report describes a fundamentally different approach to polymer modification by radical chemistry,
wherein control is imposed on both reaction dynamics and reaction yields. Functional nitroxyls such as
4-acryloyloxy-2,2,6,6-tetramethylpiperidin-N-oxyl (AOTEMPO), when used at a fraction of the peroxide
concentration, trap macroradical intermediates in the early stages of the process, providing an induction
period during which molecular weight is substantially unchanged. The polymer-bound alkoxamine
functionality introduced during the induction period is activated by residual initiator once all AOTEMPO
is consumed, leading to a different reaction outcome than that observed in the absence of the additive.
In the case of ethylene-rich polymers, cross-linking reactivity is dramatically enhanced by
oligomerization of pendant acrylate groups. In the case of propylene-rich thermoplastics, bound
acrylate oligomerization outcompetes macroradical scission to yield thermoset derivatives that are not
otherwise accessible. A combination of model compound experiments and rheological studies of
polyolefin formulations is used to demonstrate the scope and practical utility of this new polymer
modification chemistry.
O-18
Probing Interparticle Polymer Diffusion in Latex Films using Pyrene Excimer
Fluorescence
Remi Casier, Jean Duhamel, Mario Gauthier
Institute of Polymer Research, Waterloo Institute for Nanotechnology,
Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1
Latex dispersions have many industrial applications. One such application is the
preparation of homogenous films used for both decorative and protective coating. The formation
of a film prepared from a latex dispersion is typically divided into three stages; water
evaporation, particle deformation, and particle coalescence. As the latex particles coalesce,
polymer chains within an individual particle diffuse into the surrounding particles resulting in the
formation of polymer-polymer entanglements and ultimately the fusing of adjacent particles into
a single continuous film. As such, the final properties of a film, such as porosity and mechanical
robustness, are directly related to the extent of coalescence between neighbouring latex particles.
Over the past 30 years several methods have been developed to quantitatively measure the
interparticle polymer diffusion (IPD) during the film formation process. To this date, the most
commonly used method is fluorescence resonance energy transfer (FRET). Although FRET
provides a powerful tool in which to probe IPD, the procedure requires to carefully synthesize
two fluorescently labeled latexes and the use of expensive instrumentation and complex
mathematics. To this end, we provide an alternate, and also much simpler, method using pyrene
excimer fluorescence.
When pyrene is excited by a photon of light it emits with a characteristic monomer peak.
If the excited monomer encounters a ground-state pyrene an excimer is formed, causing a change
in the fluorescence profile. The amount of excimer formed is measured using a steady-state
fluorometer as the ratio of the intensity of the excimer (IE) over that of the monomer (IM), namely
the IE/IM ratio. A film prepared from a small amount of pyrene-labeled latex in a matrix of native
latex will initially exhibit a high IE/IM ratio since the polymer chains containing pyrene are
crowded together. As film formation occurs, the polymer chains containing the pyrene pendants
will diffuse into the surrounding native particles. As this occurs, the local pyrene concentration
decreases, resulting in a drop in the IE/IM ratio. By monitoring the IE/IM ratio of a film over time,
a profile of the extent of mixing between adjacent particles was prepared. Using a Fickian
diffusion model, the diffusion coefficients of the polymer chains bearing the pyrene pendants
were also determined. To further the analysis, the apparent activation energy of diffusion of the
polymer chains were also calculated and found to agree closely with published values.
O-19
Precursor effects on the structure and properties of polymernetworks synthesized using molecular dynamics
Shimiao Zhang and Li Xi∗
Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada
The effects of precursor topology on the formation, structure and mechanical properties ofpolymer networks are studied using coarse-grained molecular models. Three different sets of pre-cursors are designed in a way that in the ideal limit of complete conversion they would lead to anidentical network structure. Molecular dynamics is then used to virtually synthesize crosslinkedpolymers from these precursors and the resulting material structures and properties are compared.Little difference is observed in commonly examined properties including the radial distributionfunction, macroscopic statistics of network connectivity, and glass transition behaviors. The elas-tic modulus of the final network however depends strongly on the precursor topology. The totalnumber of elastic strands in the network is found to correlate strongly with the elastic modulus formost of the network formation process, except at the highly-crosslinked limit where substantialdiscrepancy is observed between networks from different precursors. Although these final net-works contain a similar level of structural defects, the choice of precursor has substantial impacton the spatial distribution of the defects, which explains the precursor dependence of their elasticmodulus. Our results indicate that the choice of precursor should be an important consideration inconstructing molecular models for crosslinked polymers. It also provides insights into the experi-mental design of such materials.
∗Email: xili@mcmaster.ca
O-20
1. Israelachvili, J. N. Intermolecular and Surface Forces, 3rd ed. Elsevier, NY, 2011, pp 312-318.
Probing Intramacromolecular Forces by Pyrene Excimer Fluorescence
Justin Raimbault, Remi Casier, Hunter Little, Jean Duhamel
Institute for Polymer Research, Waterloo Institute of Nanotechnology, Department of Chemistry,
University of Waterloo, ON N2L 3G1, Canada
Intramacromolecular forces (IMFs) of a macromolecule control its conformation and deformability
under stress, which in turn affect its rheological properties in solution. These properties have found
numerous industrial applications such as in oil recovery, paints, and cosmetics. The importance of IMFs in
the formation of macromolecular assemblies has led to an intense scientific effort devoted to their
characterization. However, all current methods for characterizing IMFs involve tethering the nanometer-
scale macromolecule of interest to two macroscopic surfaces, such as silica beads or mica plates, pulling
the surfaces apart, and monitoring the force exerted by the macromolecule on the surfaces.1 In these studies,
the macroscopic surfaces and the linkers tethering the macromolecule to the surfaces are expected to have
no effect on the IMFs.
In contrast, the present study investigates how excimer formation between the pyrene labels
attached to the ends of a series of poly(ethylene oxide)s (PEO-Py2) can yield quantitative information on
the IMFs experienced by these macromolecules. Instead of being tethered to macroscopic surfaces, the
pyrenyl end groups are encapsulated inside nanometer-scale sodium dodecyl sulfate (SDS) micelles. These
experiments provide a first example where the IMFs of macromolecules freely floating in solution are
probed quantitatively without being tethered to a macroscopic surface.
A series of PEO(X)-Py2 constructs, where X represents the PEO molecular weight and is equal to
2.0, 3.4, 5.0, 6.0, 8.0, and 10.0K g/mol, were studied using time-resolved fluorescence in solutions of SDS
micelles and varying sodium chloride (NaCl) concentrations. The negatively-charged SDS micelles
experience an electrostatic repulsion force which can be screened upon addition of NaCl, effectively
controlling intermicellar distances. For long PEO(X)-Py2 polymers and small intermicellar distances, the
PEO(X)-Py2 chains can bridge two micelles where each pyrene end-group is isolated in separate micelles.
Polymers which bridge two micelles experience an elastic restoring force since a stretched polymer is not
in its lowest-energy conformation. The presence or lack of excimer formation between two pyrenes can be
used to assess chain conformation. The intermicellar repulsive force and the polymeric elastic force have
been calculated and correlated to the onset of bridging and the results indicate that the IMFs of the polymer
constructs considered in this study were within 1-2 pN.
Elastic Restoring Force
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easin
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nic S
trengthD
ecre
asi
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Ch
ain
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Electrostatic Repulsion Force
O-21
Azobenzene-modified silk gels for two-photon light induced surface patterning
Michael Landrya, Mark Cronin-Golombb, Christopher J. Barretta
aDepartment of Chemistry, McGill University, Montreal, Canada, H3A 0B8 bDepartment of Biomedical Engineering, Tufts University, Medford, MA, USA, 02155
Abstract: Silk fibroin from Bombyx mori silkworms is used in diverse materials applications due to its rich protien and polymer chemistry.1 Silk can be processed into a variety of material classes that are suitable for biological applications, such as tissue engineering and cell guidance. Further enhancement of its properties can be achieved through chemical modifications of the amino acid side chains – such as tyrosine. One method to retain the biocompatibility of silk, while enhancing its optical properties is functionalization with azobenzene, yielding a material called azosilk.2 Typically, azobenzene modification is performed by reaction of tyrosine with a variety of diazonium salts.
By utilizing a confocal microscope, we were able to irradiate the surface of the hydrated gels, yielding fluorescent surface patterns under 800 nm (two-photon) irradiation. The written patterns can be easily visualized by observing the fluorescence emitted at 550 nm, excited by 800 nm. In this microlithographic process, out-of-plane expansion of the film causes small micrometre-sized blisters to form on the surface. These micro-blisters were characterized using AFM, and exhibited a dramatic 10-fold decrease in modulus associated with photo-softening. The induced radius of curvature associated with blister formation, together with photo-softening are expected to be valuable material characteristics for guided cell growth.
References
1. B. P. Partlow et al., Adv. Funct. Mater. 2014, 24, 4615.
2. A. R. Murphy et al., Biomaterials 2008, 29, 4260.
O-22
Conformation of Amylose in DMSO Probed by Pyrene Excimer
Fluorescence
Lu Li, Jean Duhamel
Institute for Polymer Research, Department of Chemistry, University of Waterloo,
200 University Ave W, Waterloo, ON N2L 3G1
Water, dimethyl sulfoxide (DMSO), and water-DMSO mixtures have been shown to
effectively solubilize starch. Despite much experimental work done on dilute solutions of amylose,
its conformation in DMSO, whether a random coil or a helix, is still a matter of controversy. Since
the two conformations would be expected to result in macromolecules displaying very different
internal dynamics, pyrene excimer formation was applied to characterize the internal dynamics of
amylose in DMSO. In this study, amylose and poly(methyl crylate) were randomly labeled with
pyrene to yield a series of Py-Amylose and Py-PMA constructs and their ability to form excimer
in DMSO was characterized quantitatively by steady-state and time-resolved fluorescence.
First, the ratio of the fluorescence intensity of the excimer over that of the monomer,
namely the IE/IM ratio, was obtained from the fluorescence spectra. Second, the product
<kblob×Nblob>, where Nblob is the number of monomers found in the volume probed by an excited
pyrene and referred to as a blob and kblob is the rate constant of excimer formation inside a blob,
was obtained from the Fluorescence Blob Model Analysis (FBMA) of the fluorescence decays.
Both IE/IM and <kblob×Nblob> yielded similar values in terms of moles of pyrene per backbone atom
(Py/BBA) for Py-Amylose and Py-PMA. Since IE/IM and <kblob×Nblob> reflect the efficiency of
pyrene excimer formation, the similar behavior observed for both parameters obtained for rigid
amylose and flexible PMA could only be rationalized by postulating that amylose adopted a
compact helical conformation in DMSO. To confirm whether this was possible, molecular
mechanics optimizations (MMOs) were conducted with the HyperChem program on Py-Amylose
assuming that amylose adopted a helical conformation in DMSO. By determining the extent of
overlap between two pyrene labels attached onto helical amylose, it was found that two pyrene
labels would overlap properly, and thus form excimer efficiently, if they were separated by no more
than 5 anhydroglucose units up and down the amylose helix corresponding to a total of 5 + 5 + 1 =
11 units in perfect agreement with our findings that <Nblob> obtained from the FBMA of the
fluorescence decays equaled 11 ± 2. This study provides a new example on how pyrene excimer
fluorescence in combination with MMOs can be applied to provide structural information on
macromolecules that adopt a helical conformation in solution.
Figure 1: Plot of A) Nblob and B) <kblob×Nblob> as a function of pyrene content. ( ) PMA
before degassing, ( ) PMA after degassing, ( ) amylose before degassing, and ( )
amylose after degassing.
B) A)
O-23
Rapid and Efficient Separation of Oil from Oil-in-Water Emulsions Using a Janus Cotton
Fabric1
Zijie Wang, Yu Wang, and Guojun Liu
Queen’s University, Kingston, ON, Canada K7L 3N6
The fast and efficient separation of oil from oil-in-water emulsion is industrially important.
Superhydrophobic filters with pore sizes reaching hundreds of micromaters have been used in the
past to separate oil rapidly from simple oil/water mixtures that are created by shearing oil by
mechanically shearing oil/water mixtures without using a surfactant. However, these filters
cannot separate oil from surfactant-stabilized oil-in-water emulsion. The filters work for simple
oil/water mixtures because oil droplets are not stable in this case and readily coalesce into a phase
that fills the pores of the superhydrophobic filters. We further propose that the impregnating oil
not only blocks water permeation but also serves as sites for additional oil deposition and also as
the reservoirs fueling selective oil transport through the superhydrophobic filter. The filters do
not work for surfactant-stabilized emulsions because the oil droplets in this case are too stable to
aggregate into large droplets that would fill the filter pores and then permeate the filters.
We report in this talk a the design and preparation of novel bi-functional Janus cotton fabric
that can separate oil from oil-in-water emulsions.1 This fabric is superhydrophobic on one surface
and polyamine-bearing on the other. When used as a filter, the polyamine-bearing side causes the
micrometer-sized oil droplets to coalesce. The coalesced oil then fills fabric pores on the
superhydrophobic side and selectively permeates it. Oil separation using this method is rapid and
the separated oil is pure. Furthermore, the content of the model oil hexadecane (HD) in water
after a separation can be reduced to less than 0.03 ± 0.03 vol%. These features suggest the
practical potential of this technology.
Reference
Wang, Z. J.; Wang, Y.; Liu, G. J., Rapid and Efficient Separation of Oil from Oil-in-Water Emulsions Using a Janus Cotton Fabric. Angewandte Chemie-International Edition 2016, 55 (4), 1291-1294.
O-24
Modification of Cooked Waxy Corn Starch with Alkenyl Succinic Anhydrides
Ryan C. Amos, Mario Gauthier*
Institute for Polymer Research, Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1; gauthier@uwaterloo.ca
Starch, as the second most abundant biopolymer, is a low-cost, readily available and renewable carbohydrate. Native starch is composed of amylose and amylopectin forming granules that are non-dispersible in water. Cooking of the starch, a process known as gelatinization, breaks down the granule structure, allowing the dispersion of free polymer chains in solution. After gelatinization the starch chains are more readily available for chemical modification. The modification of starch with alkenyl succinic anhydrides can be carried out in a batch slurry system in water. The addition of an alkenyl succinic anhydride introduces hydrophobic character due to the alkyl chain, and an anionic group results from opening the anhydride ring (Figure 1). The modification of starch allows tailoring of the properties of the resulting products. Alkenyl succinic anhydride-modified starch has found uses as thickener in food, binder in paper making, and in environmentally friendly adhesives. This presentation will focus on the synthesis of different alkenyl succinic anhydride-modified starches in batch aqueous slurry systems, obtained using sodium hydroxide as base and without organic solvents. Cooked waxy corn starch was modified to different extents with octenyl succinic anhydride (OSA), dodecenyl succinic anhydride (DDSA), phthalic anhydride, and 1,2,4-benzenetricarboxylic acid anhydride. The resulting products were characterized by 1H NMR spectroscopy and gel permeation chromatography.
O
OHHO
OH
O
O
OHO
OH
O
O
O
OR
O
O
ONa RpH ~9
1 h
Figure 1. Modification of starch with alkenyl succinic anhydride.
O-25
Water Based Approach to Asymmetric Cotton Fabric for Oil Separation from Emulsions
Morgan Lehtinen, Zijie Wang, Claudia Grozea, and Guojun Liu
Queen’s University, Kingston, ON, Canada K7L 3N6
Oil needs to be separated from oil-in-water emulsions in some industrial processes and in the treatment of certain waste water. Our group recently reported the use of asymmetric cotton fabrics as filters to separate oil from oil-in-water emulsions.1 The fibers in such an asymmetric fabric swatch bore on its top side polydimethylsiloxane (PDMS), thus displaying superhydrophobic properties. Fibers of its bottom side bore poly[(2-dimethylamino) ethyl methacrylate], PDMAEMA, which upon protonation became charged and hydrophilic. While the hydrophilic side coalesced emulsified oil droplets, the coalesced oil filled the pores of the fabric and selectively permeated the oil through the superhydrophobic side. This method of separation was fast and efficient. However, the preparation of the asymmetric fabric in the previous proof-of-concept study1 was tedious involving sample photolysis and use of organic solvents. In this work, a new protocol is developed for the preparation of asymmetric cotton fabric bearing PDMS on one side and DMAEMA groups on the other. The polymer coatings in this new protocol were deposited via aqueous processes and the polymer were thermally grafted onto cotton fibers. More interestingly, the asymmetric cotton fabric samples prepared from this simplified protocol separated oil from their emulsions in water equally efficiently and rapidly as the previous fabric swatches. This new method should be useful for modifying fabric also for other applications.
Reference 1. Wang, Z. J.; Wang, Y.; Liu, G. J. Rapid and Efficient Separation of Oil from Oil-‐in-‐
Water Emulsions Using a Janus Cotton Fabric. Angew. Chem. Int. Ed. 2016, 55,1291-‐94.
O-26
Cellulose Nanocrystals Made CO2-Responsive by Polymer Grafting
Farhad Farnia, Weizheng Fan, Yves Dory, Yue Zhao*
Département de chimie, Université de Sherbrooke, Sherbrooke, Canada
(Email : yue.zhao@usherbrooke.ca)
Cellulose nanocrystals (CNC) were rendered responsive to CO2 in aqueous solution by grafting
poly(2-(N,N-diethylaminoethyl)methacrylate) (PDEAEMA) onto the surface. The grafting was
achieved by surface-initiated ATRP. The polymer-grafted CNC (CNC-g-PDEAEMA) was
characterized by using a number of techniques including 1H NMR and dynamic light scattering
(DLS). They showed reversible CO2-sensitive dispersion state in aqueous solution, as a result of
the switch between charged (protonated) and neutral (deprotonated) tertiary amine groups on the
polymer induced by alternating bubbling of CO2 and N2.
O-27
POSTER SESSION / SESSION D’AFFICHES
Arborescent Polypeptides based on Poly(γ-benzyl L-glutamate) for Drug Delivery Applications
Mosa Alsehli, Mario Gauthier
Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo, Ontario N2L 3G1
In recent years polymeric micelles have attracted much attention as promising drug delivery nanocarriers because their sizes and structures are similar to those natural carriers in biological systems. Herein we report the synthesis of biocompatible and biodegradable arborescent polymeric micelles with poly(γ-benzyl L-glutamate) (PBG) and poly(ethylene oxide) segments. The arborescent poly(γ-benzyl L-glutamate) core synthesized by ring-opening polymerization of γ-benzyl L-glutamic acid N-carboxyanhydride initiated with n-hexylamine and successive grafting reactions via standard peptide coupling techniques. Amphiphilic unimolecular micelles of poly(benzyl L-glutamate)-g-poly(ethylene oxide) copolymers were obtained by grafting the hydrophobic arborescent PBG substrates with hydrophilic side chains of poly(ethylene oxide) by the same peptide coupling techniques. The synthesized polymers were characterized using 1H NMR, gel permeation chromatography (GPC), atomic force microscopy (AFM), dynamic light scattering (DLS) and transmission electron microscopy (TEM).
The encapsulation and release properties of these nanocarriers were investigated using doxorubicin (DOX) as a model hydrophobic anticancer drug, which was effectively encapsulated via three different methods. Doxorubicin hydrochloride (DOX.HCl) was successfully loaded into the hydrophilic arborescent poly(L-glutamic acid)-g-poly(ethylene oxide) copolymers via electrostatic interactions. The hydrophobic form of DOX was physically entrapped within the core of the poly(γ-benzyl L-glutamate)-g-poly(ethylene oxide) unimolecular micelles. Doxorubicin was also conjugated to the poly(benzyl L-glutamate)-g-poly(ethylene oxide) unimolecular micelles via pH-sensitive hydrazone bond. The drug release profiles for these systems were slow at physiological pH (7.4) but increased at pH (5.5). The unimolecular micelles exhibited a pH-sensitive drug release behavior. The synthesized arborescent polymeric micelles, given their unique structure and biodegradability, could potentially be used as a nanocarriers drug delivery application.
P-1
Development of self-healing polymeric networks crosslinked by dynamic linkages
So Young An and Jung Kwon Oh
Department of Chemistry and Biochemistry, Concordia University
soyoung3430@gmail.com
Intrinsic self-healing materials have attracted increasing attention due to their built-in ability to self-heal physical damages utilizing well-established reversible crosslinking chemistry. Dynamic linkages such as ionic interaction and disulfide bonds are excellent candidates to be explored in designing self-healable crosslinked material since they can be cleaved/disturbed in response to external stimuli and then subsequently rebounded, inducing self-healing behavior. Here, we present a novel poly(ethylene glycol) (PEG)-based multiblock copolymer (diPEGss-COOH) consisting blocks with pendent disulfides and other blocks with carboxylic acid end groups. Our methods to prepare diPEGss-COOH mutiblock copolymer include combination of consecutive atom transfer radical polymerization (ATRP) followed by facile cleavage reaction to yield COOH end groups. Such polymer can be oxidized to form crosslinked networks consisting ionic crosslinks and disuflides in which exhibit self-healing ability. Self-healing mechanism in this system can be achieved through its dynamic linkages: 1. Ionic crosslinkers and migration of coutner-ion 2. Cleavage of disulfides to corresponding thiols or thiyl radicals in which can re-form disulfides again. One of the novelty of our system lies on the incorporation of two different dynamic linkages with enhanced self-healing behaviors in which can be advantageous over other crosslinked materials using only single dynamic linkage. This novel design along with their tunable self-healing kinetics well demonstrate the versatility of our method to prepare self-healable polymeric crosslinked networks which has a promising potential towards the development of multifunctional industrial applications.
P-2
Synthesis and Surface Modification of Lanthanide (NaLnF4) Nanoparticles for High-Sensitivity Mass Cytometry Bioassays
Lemuel Tong,a Jothirmayanantham Pichaandi,a Loryn Arnett,a Alexandre Bouzekri,b Olga Ornatsky,b Vladimir Baranov,b Mitchell A. Winnika
aDepartment of Chemistry, University of Toronto, Toronto, Ontario, Canada, M5S 3H6 bFluidigm Canada, 70 Esna Park Drive #12, Markham, Ontario, Canada, L3R 6E7
Analysis of cellular biomarkers gives information about the state of a cell, and in cancer cells, can indicate the type of cancer and stage in its development. Expression of biomarkers can be assessed using labelled antibodies. In mass cytometry, many biomarkers can be analyzed simultaneously by tagging each type of antibody with a different metal isotope. This technique is able to achieve single mass unit resolution by exploiting time-of-flight inductively-coupled plasma mass spectrometry (see Figure). The signal in mass cytometry is proportional to the number of metal atoms per antibody. Currently, lanthanide (Ln) metals are the most commonly used elemental tags, due to their stability and low cellular background. However, antibodies labeled with metal chelating polymers carry only ~250 Ln atoms, and cannot detect low copy number biomarkers (<103 copies per cell). Therefore, we would like to use Ln nanoparticles (NPs) which contain ~104 Ln atoms per particle. For use in mass cytometry the NPs are required to be uniform, colloidally stable in physiological media, and have functional groups for bioconjugation. We have synthesized a library of oleate capped NaLnF4 NPs (Ln = Sm to Ho, and Y) using the co-precipitation method. These NPs can be synthesized with diameters ranging from 4 to 30 nm with a narrow size distribution (CV < 5%). Since the as-prepared NPs are hydrophobic, the NPs were transferred into aqueous buffer through lipid encapsulation by thin film hydration. Both hydrophobic NPs coated with lipid micelles and hydrophilic NPs coated with liposomes demonstrated long term colloidal stability in saline buffers. Finally, functional groups were introduced through lipid insertion for bioconjugation to secondary antibodies. Preliminary mass cytometry results with different cancer cell lines indicate that the NPs can specifically target cell-surface biomarkers. There is still a high background signal from non-specific binding to cells. This is a major problem to be overcome in future research.
P-3
Probing the Interactions between Pyrene-labeled Gemini Surfactants and Non-Gemini Surfactants by Fluorescence
Abdullah Basalem, Jean Duhamel
Institute for Polymer Research, Waterloo Institute for Nanotechnology, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1
Gemini surfactants have attracted scientists’ attention due to their unique structure and properties. Their structure resemblance to the lipids that constitute cell membranes makes them ideal candidates as non-viral vectors for DNA delivery. To better determine the behavior of the surfactant in complexes made of gemini surfactants and DNA, a pyrene labeled gemini surfactant was synthesized and its fluorescence was characterized. Previously, the pyrene labeled gemini surfactant Py-3-12 shown in Figure 1a was prepared to study such complexes [1]. Unfortunately, Py-3-12 lacked one of the key features of pyrene, namely the ability to probe the polarity of its local environment due to its substitution with an n-alkyl chain.
According to a new study, addition of an oxygen in the beta position to pyrene restores the pyrene sensitivity to its local environment [2]. With that in mind, a new pyrene labeled surfactant referred to as PyO-3-12 in Figure 1b has been synthesized and characterized. Steady state fluorescence shows that addition of oxygen in the substituent restored the sensitivity of pyrene to the polarity of its environment. This presentation will describe some of the experimental results obtained thus far on the interactions between PyO-3-12 and other surfactants, namely SDS and CTAB. Most interestingly, intermolecular complexes between SDS and PyO-3-12 are found to form at concentrations as low as 2.5 µM surfactant!
Figure 1: Structure of Py-3-12 (a) and PyO-3-12 (b)
References: 1. Christine Keyes-Baig, Jean Duhamel and Shawn Wettig, Langmuir 2011, 27, 3361–
3371. 2. Shiva Farhangi and Jean Duhamel, J. Phys. Chem. B 2016, 120, 834–842.
P-4
AOTEMPO-mediated Synthesis of Polypropylene-based Thermoplastic Vulcanizates
Michael W. Bodley and J. Scott Parent Department of Chemical Engineering
Queen’s University Kingston, Ontario, Canada.
Thermoplastic vulcanizates (TPVs) made by reactive blending of polypropylene (PP) and ethylene-rich
elastomers are widely used in automotive applications that require a balance of material strength and
toughness. Conventional TPVs are synthesized by mixing PP, elastomer, and phenol-formaldehyde resin
curatives to yield a crosslinked elastomer phase that is dispersed in a PP matrix. Peroxide-initiated
crosslinking formulations, while providing cleaner products, have not found use for PP-based TPVs,
owing to the susceptibility of PP toward radical degradation. We have recently discovered the ability of
nitroxyls bearing polymerizable functionality, such as 4-acryloyloxy-2,2,6,6-tetramethylpiperidin-N-oxyl
(AOTEMPO), to mitigate PP degradation during reactive processing. Moreover, AOTEMPO + peroxide
formulations provide predictable induction periods during which changes to polymer MW are
suppressed by nitroxyl trapping of macroradical intermediates. In this work, the ability of AOTEMPO
delay the onset and control the outcome of peroxide modifications is used to prepare TPVs with
predictable morphology and phase viscosities. The advantages of this approach over conventional
coagent-based formulations are demonstrated by rheological and microscopy analyses, as well as
physical property assessments.
P-5
Poster
Controlled Oxidation of Thiazole Containing Conjugated Polymers
Rob Claridge, Derek Schipper
Department of Chemistry, University of Waterloo
Conjugated polymers have garnered substantial attention in the field of materials due to their interesting optoelectronic properties, low cost, impact resistance and processability. In addition, they have the ability to be easily fine-tuned in order to alter their optoelectronic properties. This makes conjugated polymers viable materials for many electronic applications, including; photovoltaics, OLED’s, field effect transistors and sensors. When synthesizing conjugated polymers for electronic applications, altering the monomers before polymerization in order to fine-tune properties can be a useful method, but sometimes the alteration of functional groups or other changes in the monomer can cause problems during the polymerization process. This effectively limits the amount of ‘tuning’ that can be performed prior to polymerization. In contrast, altering a polymer post-polymerization can require as little as one synthesis to create a family of polymers with differing properties. One such method of changing electronic properties, such as bandgap is though chemical oxidation. Thiazole derivatives have shown good performance in conjugated polymer research and are relatively easy to oxidize to the N-oxide. Therefore, through controlled oxidation of a thiazole containing conjugated polymer a family of polymers with differing bandgaps can be obtained. This versatility would allow for targeting application specific characteristics.
N
S
N
S
C9H19C9H19
p
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OO
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C9H19C9H19
Sq
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C9H19C9H19
S n
P-6
Atom Transfer Radical Polymerization (ATRP) Grafting of Starch Nanoparticles with Sodium Acrylate
Joanne Fernandez, Nicole Tratnik, Mario Gauthier*
Institute for Polymer Research, Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1; gauthier@uwaterloo.ca
Graft copolymers derived at least in part from renewable resources, such as starch, have numerous potential applications in the industry. Starch is a biocompatible, renewable, and biodegradable polysaccharide. Its abundance and relatively low cost have led to substantial interest in its use as a base material for a variety of applications.1 This research intends to explore the synthesis and the properties of various graft copolymers derived from starch nanoparticles (SNPs) and sodium acrylate. The SNPs, supplied by EcoSynthetix (Burlington, ON), were obtained via twin-screw extrusion of corn starch, water, glycerol and a cross-linking agent. Through modification, the SNPs can acquire characteristics comparable to synthetic petroleum-based polymers.2,3
Various methods are available to synthesize graft copolymers. Most techniques involve radical polymerization, as it can take place in aqueous media with good yield of the final product. Graft polymerization via ATRP can generate well-defined polymers, as this reaction is a type of radical polymerization where the chain ends are reversibly deactivated by atom transfer via a catalyst.4 Activators Regenerated by Electron Transfer (ARGET) ATRP involves the addition of a reducing agent to reactivate the catalyst, which in turn reduces the amount of transition metal required. Poly(sodium acrylate)-grafted starch is interesting as superabsorbent material and can be used as a sizing agent in textiles. This presentation will focus on the synthesis of poly(sodium acrylate)-modified SNPs via ARGET ATRP. This was done by coupling bromoisobutyryl bromide with the SNPs in dimethyl sulfoxide, purification, and ARGET ATRP under nitrogen in an aqueous medium. The SNPs were systematically modified and characterized using nuclear magnetic resonance (NMR) spectroscopy and dynamic light scattering (DLS) measurements.
References 1. G. Moad, Prog. Polym. Sci., 2011, 36, 218.2. A. Pourjavadi, M. J. Zouhuriann-Mehr, Starch-Stärke, 2002, 54, 140.3. V. D. Athawale, V. Lele, Starch-Stärke, 1998, 50, 426.4. M. Chanda, Introduction to Polymer Science and Chemistry, CRC Press: Boca
Raton, 2013.
P-7
Synthesis and post functionalization of polyetherethersulfone-allyl
copolymers for applications in fuel-cell membranes
Jacob Dion Gagné, Adrien Faye and Josée Brisson
CERMA (Centre de Recherche sur les Matériaux Avancés) and CQMF (Centre
Québécois sur les Matériaux fonctionnels), Département de chimie, Faculté des sciences
et de génie, Université Laval
Polyetherethersulfone-allyl random copolymers were synthesized via polycondensation
from 4,4’-bis(4-hydroxyphenoxy) diphenyl sulfone (HPDS), bis(4-fluorophenyl) sulfone
(FPS) and cis-1,4-dichlorobut-2-ene. Resulting copolymers were functionalized by using
thiol-ene click reactions to graft sulfonated molecules onto the polymer chain, thereby
providing a flexible means of modifying the copolymer properties for use in proton
exchange membrane fuel cells (PEM-FCs). The degree of substitution of double bonds was
studied over irradiation time by 1H NMR, and the effect of UV-light on the degradation of
the copolymers was evaluated by measuring changes in molar mass by size exclusion
chromatography (SEC). After the reaction, a certain number of unreacted double bonds
remain, which were used for post-fabrication crosslinking. This results in a decrease in
solubility of resulting films or membranes, thus solving a problem often observed for
PEES-based polymers. Ion exchange capacity of resulting films was investigated by
titration of the sulfonic acid groups, and water uptake was also determined. Resulting
properties will be discussed, along with possible route to further improve them..
DMAPDMSO48 hrs, tp hv, 40w, 365nm
HS S
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P-8
Polyglyoxylate Nano- and Micro-particles for Triggered Drug Release
M. Thomas Gambles,1 Bo Fan,2 and Elizabeth R. Gillies1,2 1Department of Chemistry, 2Department of Chemical and Biochemical Engineering, The
University of Western Ontario, London, ON, N6A 5B7, Canada
Hydrophobic polymers can be self-assembled into particles of both the nano-scale and the macro-scale using oil-in-water emulsion techniques. Polymer particles, of this nature, can be utilized as drug delivery vehicles with incorporation of a variety of different payloads. Polymers featuring biocompatible and biodegradable characteristics have been widely sought after for this type of in vivo drug delivery. The development of such systems could lead to biodegradable self-assembling biomaterials with the potential for the attachment as well as encapsulation of reactive compounds.
Poly(ethyl glyoxylate) (PEtG), previously reported by our group,1 is a polymer that degrades ultimately to glyoxylic acid hydrate, a byproduct of human metabolism,2 making it a good candidate for particle assembly and payload encapsulation for in vivo drug delivery. The low ceiling temperature of PEtG makes the polymer inherently unstable at room temperature, undergoing spontaneous end-to-end depolymerization. This depolymerization can be prevented by capping the ends of the polymer with an inert small molecule. Previous research has gone into developing stimuli-responsive end-caps, which has yielded end-caps responsive to pH, temperature, UV light and other stimuli. Once the stimulus is introduced to these polymers, the small molecule end-cap is chemically altered resulting in loss of the end-cap and depolyermization occurs. This offers a triggerable degradation system that can be utilized for particle assembly and controlled release of payload.
Herein we describe the use of PEtG, capped with a UV-light sensitive end-cap, for particle assembly and payload encapsulation. Optimizing the oil-in-water emulsion technique for both nano and macro-sized particle systems, yielded a range of particle sizes with different drug encapsulation and release profiles with control over drug release. The particles were characterized by electron microscopy and optical microscopy and drug release was studied by UV-visible spectroscopy and fluorescence spectroscopy.
1. Fan, B.; Trant, J. F.; Wong, A. D.; Gillies, E. R. "Polyglyoxylates: A versatile class oftriggerable self-immolative polymers from readily accessible monomers" J. Am. Chem. Soc. 2014, 136, 10116-10123 2. Funai, T.; Ichiyama, A. “High-performance kiquid chromatographic determination ofglyoxylate in rat liver” J. Biochem. 1986, 99, 579-589
Triggered Degradation
Particle Assembly with Payload Encapsulation
P-9
ASSOCIATIONS BETWEEN EP COPOLYMERS IN BASE OILS PROBED BY FLUORESCENCE
Kiarash Gholami, Solmaz Pirouz, Jean Duhamel
Institute for Polymer Research, Waterloo Institute for Nanotechnology, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1
Abstract
The goal of this project is to apply fluorescence to characterize the level of interpolymeric interactions that take place between ethylene propylene (EP) copolymers used as viscosity index improvers by the oil industry. A semicrystalline (EP(SM)) and an amorphous (EP(AM)) EP copolymer were maleated and fluorescently labeled with 1-pyrenemethylamine to yield two Py-EP samples. The fluorescence signal of the Py-EP samples can be analyzed to yield finter, the molar fraction of pyrene labels that form excimer intermolecularly upon encounter between an excited and a ground-state pyrene. The fraction finter is a measure of the level of intermolecular interactions that take place between the Py-EP samples. It is determined by acquiring the fluorescence spectra of Py-EP solutions at low and high Py-EP concentrations. Since the ratio of the intensity of the pyrene excimer over that of the monomer obtained from the fluorescence spectra of the Py-EP solutions is proportional to the local pyrene concentration (CPy), the fluorescence measurements conducted at low and high Py-EP concentration provide a measure of CPy when pyrene excimer is formed intra and/or intermolecularly. These CPy values were then employed to calculate finter. finter determined as a function of temperature for the two polymers in toluene in the presence and absence of wax.
Figure 1: Plots of the molar fraction f inter as a function of temperature in toluene.
References:
1. Pirouz, S. Quantitative Characterization of Polymeric Engine Oil Additives in Solution byFluorescence. PhD thesis, 2015, 1-182.
2. Pirouz, S.; Duhamel, J.; Jiang, S.; Duggal, A. Quantifying the Level of IntermacromolecularBetween EP Copolymer Interactions by Using Pyrene Excimer Formation. Macromolecules 2015,48, 4620-4630.
P-10
Fluorescently Labelled Latex Particles to Monitor Film Formation Victoria Hisko, Mario Gauthier, Jean Duhamel
Institute for Polymer Research, Waterloo Institute for Nanotechnology, Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada, N2L 3G1
Film formation from latex particles has been of commercial importance for many years, particularly in the paint industry. The film formation process in key to producing desirable films. In this process, interparticle diffusion (IPD) by polymer chains leads to the formation of entanglements. The extent of IPD determines how good the mechanical properties of the film will be.
To probe the IPD of latex particles, some latex particles will be labelled with pyrene. As the polymeric chains diffuse and entangle, the local pyrene concentration (CPy) will decrease, thereby leading to a decrease in the IE/IM ratio measured using steady-state fluorescence spectroscopy. Unfortunately, pyrene-containing monomers are very hydrophobic and difficult to incorporate into polymeric chains by emulsion polymerization, since they must diffuse across the water phase. To counter their hydrophobicity, oligo(ethylene glycol) units can be added into the monomer. The optimal monomer must be hydrophilic enough to readily diffuse across the water phase in the emulsion polymerization for good incorporation, but hydrophobic enough not to remain in that phase. The monomer must also be sufficiently small so as not to affect properties of the native latex such as the glass transition temperature (Tg). Longer oligo(ethylene glycol) spacers have also been shown to cause unwanted crosslinking in the emulsion polymerization reaction. This issue can be minimized using a chain transfer agent such as dodecanethiol.
The pyrene-labelled monomers were synthesized as shown in Schemes 1 – 3. For shorter oligo(ethylene glycol) spacers (n < 5) the reaction in Scheme 1 was used, while for larger spacers (n > 5) were obtained according to Scheme 2. Acylation was accomplished folowing Scheme 3. The labelled latex was then mixed with a non-labelled latex at a 5:95 weight ratio. The mixed latex was deposited onto a quartz plate and dried overnight. The resulting film was annealed in an oil bath, and the change in excimer formation was monitored as a function of annealing time via steady state fluorescence.
P-11
Dual location dual reduction and pH-responsive degradable block copolymer
micelles for enhanced cellular uptake and drug controlled release
Arman Moini Jazani and Jung Kwon (John) Oh, Department of Chemistry and Biochemistry,
Concordia University, Montreal, QC, H4B 1R6
Well-defined amphiphilic block copolymers and their self-assembled nanostructures designed
with stimuli-responsive degradation (SRD) have emerged as promising nanocarriers for cancer
therapy. Effective SRD strategy that centers on the development of new intracellular
nanocarriers having multiple stimuli-responsive cleavable linkages at multiple locations (denoted
as ML-MSRD strategy) has become increasingly desirable to address the multiple challenges of
targeted delivery. Herein, we describe our exploration of concept of ML-MSRD strategy to
develop a dual location pH-responsive and reduction-responsive ABP and its self-assembled
nanostructures. As a model system, a new amphiphilic block copolymer (ABP) consists of a
hydrophilic poly(ethylene oxide) (PEG) block and a hydrophobic polymethacrylate block having
pendant disulfide linkages (PHMssEt) is synthesized. Both blocks are synthesized from dimethyl
ketal containing initiator fitted with amino and tertiary bromide groups. Hydrophilic block is
synthesized via coupling with carbonyldiimidazole (CDI)-activated PEG, and PHMssEt block is
synthesized by atom transfer radical polymerization (ATRP). The ABPs are characterized by gel
permeation chromatography, 1H NMR and dynamic light scattering. Further, the aqueous
micellization and release study of micelles under reductive and acidic environment is assessed.
P-12
Reversible polymer networks composed of polymethacrylate with maleimide and furan groups in response to thermal stimuli for self-healing materials
Sungmin Jung, Dhamodaran Arunbabu, Jung Kwon Oh*
Department of Chemistry and Biochemistry, Centre for NanoScience Research,
Concordia University, Montreal, Quebec, Canada H4B 1R6
Email : john.oh@concordia.ca
The investigation and development of self-healing materials has gained much attention in
the last two decades because the self-healing materials have the built-in ability to mend
microcrack and physical damage which happen during operation and utilization of the
materials. Especially, Diels-Alder (DA) reaction that is a [4+2] cycloaddition involving a diene
and dienophile, is attractive for building up high-performance self-healing polymer materials
because of the “click” characteristics and thermal reversibility of the DA reaction. We
describe herein the design and synthesis of polymethacrylate that take advantage of the
versatility in tuning the densities of pendant furan-protected maleoimide group (PMIMA) and
polymethacrylate bearing pendent furan groups (PFuMA) using Atom Transfer Radical
Polymerization (ATRP). The formations of DA-crosslinked polymer networks with furan-
deprotected PMIMA which is obtained at elevated temperature and PFuMA in reactive
blends demonstrate the self-healing phenomenon by thermoreversible DA/Retro-DA reaction
according to gel-sol transition and microscopic results.
before after
Self-healing
O
N O O
O
O O
N O O
O
O
O O
O
O
N O O
O
O
O O
D / A R e t r o D / A
P M I M A P M A P F u M A
P M I M A / P F u M A c r o s s l i n k e d n e t w o r k
P-13
Rod-like Cellulose Nanostructures for Delivery of Radionuclides to Tumours
Melinda Guo,1 Sohyoung Her,2 Rachel Keunen,1 Shengmiao Zhang,1 Christine Allen,2 Mitchell A. Winnik1
1Department of Chemistry and 2Leslie Dan Faculty of Pharmacy, University of Toronto.
Rod-like nanoparticles have shown improved tumor penetration relative to their spherical
counterparts. For this reason rod-like nanoparticles are desirable for drug-delivery applications.
We investigate the modification
of rod-like cellulose nanocrystals
(CNCs) for the delivery of
radionuclides to tumors. CNCs
are both biocompatible and
biodegradeable making them
superior for drug-delivery.
Through modification of these rod-shaped nanoparticles we can delivery radionuclides directly
to tumors. We modify the CNCs using metal-chelating block copolymers with an exterior
polyethylene glycol (PEG) block to minimize protein adsorption. PEG-PGlu(DPTA)25-HyNic
polymers were synthesized and coupled to CNCs using hydrazine nicotinamide (HyNic)
coupling chemistry to form a bis-aryl hydrazone. The CNCs are readily modified and retain their
structural properties after modification with fluorescent dyes and metal-chelating polymers.
Preliminary evaluation in a human ovarian cancer cell line (HEYA8) demonstrated that these
CNCs are non-toxic and their penetration properties can be readily assessed in multi-cellular
tumor spheroids (MCTS) by optical imaging.
P-14
Characterization of Hydrophobically Modified Starch NanoParticles
by Pyrene Fluorescence
Damin Kim, Jean Duhamel*, Ryan Amos, Mario Gauthier*
University of Waterloo, Waterloo, ON N2L 3G1, Canada
Starch NanoParticles (SNPs) were hydrophobically modified with propionic and hexanoic
anhydride via esterification. Different degrees of substitution (DS) of the hydroxyl groups of the
SNPs were achieved by varying the reaction conditions. The hydrophobicity of the
hydrophobically modified SNPs (HM-SNPs) was examined with pyrene fluorescence. The
hydrophobes covalently attached to the SNPs conferred an amphiphilic character to the SNPs
whereby hydrophobic microdomains were generated and stabilized by the hydrophilic SNPs in
aqueous solution. The hydrophobic microdomains of the HM-SNPs were probed with the
hydrophobic dye, pyrene. Several parameters related to the photophysical properties of pyrene,
such as the I1/I3 ratio, the bimolecular rate constant for quenching kq, the natural lifetime 0, and
the equilibrium constant for the binding of pyrene to the HM-SNPs K, were found to respond
nicely to the hydrophobicity of the HM-SNPs, and thus the level of hydrophobic modification.
These four parameters, I1/I3, kq, 0 and K, were examined as a function of the DS and the type of
hydrophobic modification (propionic versus hexanoic acid). As the DS of hexanoic acid of the
HM-SNPs increased, pyrene experienced a decrease in the polarity of its local environment
evident from a decrease in I1/I3 while the microviscosity of the hydrophobic aggregates increased
as indicated by an increase in 0 and a decrease in kq. Moreover, the interactions between SNPs
and pyrene became stronger with increasing DS. All the parameters confirmed that the
hydrophobicity of the HM-SNPs increased with increasing DS of hexanoic acid. The parameters
also indicated that for a same DS, the environment generated by the SNPs modified with
hexanoic acid was more hydrophobic than that of the SNPs modified with propionic acid. As it
turns out, the photophysical parameters of pyrene retrieved for the SNPs modified with propionic
acid were similar to those obtained with the naked SNPs. In conclusion, hexanoic anhydride
modification of SNPs appears to be more suitable in order to increase the hydrophobicity of
SNPs. These measurements carried out with pyrene indicate that a series of HM-SNPs has been
generated whose level of hydrophobicity can be gauged based on the value of the I1/I3, kq, 0 and
K parameters.
P-15
Bulk Supramolecular Polymer From An Iron Acyl Piano Stool Complex
Nicholas Lanigan, Abdeljalil Assoud and Xiaosong Wang
Institute for Polymer Research, Waterloo Institute of Nanotechnology Department of Chemistry, University of Waterloo, Waterloo, Ontario, Canada N2L 3G1
By harnessing the attractive nature of intermolecular forces, molecules can be organized into long one-dimensional nanostructures called supramolecular polymers. Depending on the design of the monomer, the supramolecular polymer can either be rigid or flexible. Supramolecular polymers can have the same physical behaviour as covalent polymers (e.g. viscoelasticity); however, they can have additional properties due to the dynamic nature of the non-covalent bonds and high order in one-dimension. Significant progress has been made in the development of bulk supramolecular polymers using oligomers functionalized with self-complimentary end groups. In contrast, the advancement of bulk supramolecular polymers based on small molecules has been hindered. This arises due to the difficulty in designing small molecule monomers with both sufficiently strong complimentary directional interactions and mobility to assemble, while preventing crystallization.
Our group has demonstrated that an iron acyl piano stool complex PPh3CpFe(CO)(CO)(CH2)5CH3 (FpC6) is able to form a supramolecular polymer in the bulk which crystallizes over time. Differential scanning calorimetry reveals that after melting FpC6 does not recrystallize and undergoes a glass transition (Tg) at approximately 13 °C. At temperatures above the Tg, the rheological profile of FpC6 fits the Maxwell model suggesting the presence of chain entanglement. Single crystal x-ray diffraction allows the elucidation of a duplex chain structure formed via a combination of C—H---O hydrogen bonds and π—π interactions. Powdered x-ray diffraction spectra of freshly melted FpC6 have a distinctive double peak pattern corresponding to the chain structure observed in the single crystal. The iron elements in the polymer are arranged in a fused triangle configuration leading us to name this polymer a supramolecular “iron-truss” polymer. This discovery opens a variety of new design motifs for future supramolecular polymers.
P-16
Polypropylene Thermosets by VBTEMPO-mediated Peroxide Vulcanization
Kyle Ozols and J. Scott Parent Department of Chemical Engineering
Queen’s University Kingston, Ontario, Canada.
New chemistry for preparing polypropylene (PP) thermosets is described, wherein radical
degradation suffered during conventional peroxide treatment is overcome using a nitroxyl
additive bearing a polymerizable functional group. A small amount of 4-vinylbenzoic-2,2,6,6-
tetramethylpiperidin-N-oxyl (VBTEMPO) is used to trap peroxide-derived, carbon-centred
radicals during the early stages of the modification process, yielding a macromonomer
derivative in situ that crosslinks in the later stages through side-chain oligomerization. This
process has proven capable of producing thermosets with gel contents in excess of 90%, while
providing the induction period needed to shape the formulation before it is crosslinked. The
thermal stability of the alkoxyamine functionality that underlies this process is assessed, along
with the antioxidant stabilization that may be conferred by this class of functional group.
P-17
Predicting optical properties of energetic materials using DFT
Pierre-Olivier Robitaille1, 2, Mounir Jaidann1, Hakima Abou-Rachid1* and Josée Brisson2
1) Defense Research & Development Canada – Valcartier Research Centre, Government of
Canada 2459 de la Bravoure Road, Québec, QC, Canada, G3J 1X5
2) Département de chimie et CERMA (Centre de recherche sur les matériaux avancés), Faculté
des sciences et de génie, Université Laval, Québec, Canada G1V 0A6
pierre-olivier.robitaille.1@ulaval.ca
The fight against Improvised Explosive Devices (IEDs) is one of the greatest challenges facing
modern armies. A wide range of methods has been developed over the last years in order to
detect and neutralize IEDs, from classic detection methods, nuclear magnetic resonance
(NMR), infrared spectroscopy (IR) and X-ray diffraction, to less orthodox methods using the
impressive olfactory capacity of dogs, or even rats [1]. One of the most promising techniques
combines the use of electromagnetic induction, a technique used to detect the presence of
metals in the soil, and Ground Penetrating Radar (GPR), which measures the dielectric constant
of constituents present in the ground [2]. Determination of the dielectric constant of various
energetic materials (EMs) is therefore of interest in the fight against IEDs. This project aims to
develop an effective method to determine dielectric constants of various energetic materials by
using the Density Functional Theory (DFT) approach and establish a correlation to their
crystalline structure. A total of 16 basis sets were tested on 13 energetic molecules. It was
found that the CAM-B3LYP/AUG-cc-pVDZ presents the best accuracy versus time’s calculation
ratio, with deviations between experimental data and values calculated by DFT differing by less
than 5%.
References
1. Bielecki, Z., Janucki, J., Kawalec, A., Mikołajczyk, J., Pałka, N., Pasternak, M., Pustelny,T., Stacewicz, T., Wojtas, J. In Metrology and Measurement Systems 2012; Vol. 19, p 3.
2. Daniels, D.J. In Unexploded Ordnance Detection and Mitigation; J. Byrnes, Ed.; SpringerDordrecht: 2009.
P-18
Preparation and Binding Properties of Azobenzene Dyes in Soft-Bonded Azo-polymer
Complexes
Frédéric-Guillaume Rollet, Jaana Vapaavuori, Christopher J. Barrett
Department of Chemistry, McGill University, 801 rue Sherbrooke Ouest, Montréal, Québec,
H3A OB8
Azobenzene dyes represent an interesting class of molecules for their potential use as photo-
switches due to their fast, powerful and reversible trans-cis isomerization. Due to these properties,
they have been incorporated in thin films to create photo-responsive bio-compatible surfaces.
Previous efforts in creating bio-compatible surfaces covalently bind the azo moiety to the
polymer backbone. However, covalent binding of the azo dye to the polymer backbone often
requires long synthesis steps and intricate purification procedures, with uncertain
biocompatibility. Herein, we investigate new systems using non-covalent interactions.
Films of polyvinylpyrrolidone (PVP) and disperse red 1 (DR1) or methyl red (MR), have been
prepared as successful azopolymer complexes. The extent of dye loading and nature of the
binding in these films is monitored by DSC, IR, Raman and UV-Vis spectroscopy. The
interaction between dye and polymer show up to a 15 cm-1
shift in the infrared νC=O band of
PVP for both DR1 and MR and a shoulder in the νaNO2 band in the Raman Spectra of DR1/PVP
indicates aggregation at higher loading. DSC profiles show no dye melting and a depression of Tg
at lower loadings. A blue shift is observed in the UV-Vis spectra upon exposure to water vapour.
DR1 complexes change readily upon exposure to humid air and exhibit reversibility upon heating,
whereas the effect is much slower and irreversible with MR complexes.
P-19
Probing the Conformations of Polymeric Bottle Brushes in Solution by Pyrene Excimer Formation
Janine Thoma, Jean Duhamel
Department of Chemistry, University of Waterloo, ON N2L 3G1, Canada
A series of poly(ethylene glycol) (PEG) methacrylates terminated with a pyrene group
are being prepared using a range of PEG molecular weights. These macromonomers will be
polymerized using conventional radical chain polymerization to obtain polymeric bottle brushes
(PBBs). The ability of pyrene to form excimer allows one to probe the local concentration of the
pyrene end groups of the polymer in solution. Model Free Analysis (MFA) will be applied to fit
the fluorescence decays and calculate the average rate constant <k> of excimer formation. If this
project is successful it will establish for the first time the side-chain length at which the
conformation of a PBB morphs from a globular to an extended rod in solution. This will be
achieved by monitoring how <k>, which depends on the local pyrene concentration in the PBB,
shows a discontinuity in a plot of <k> versus side chain length.
Figure 1: Probing pyrene location in a globular (left) and cylindrical (right) chain conformation.
P-20
Synthesis of Cleavable Amphiphilic Block Copolymers Liying Wang, Deepak Vishnu Dharmangadan, Qiuying Zhang, Mario Gauthier*
Department of Chemistry, University of Waterloo, ON, N2L 3G1, Canada
Amphiphilic block copolymers in solution can self-assemble into different nanostructures
such as micelles, wormlike structures, and polymeric vesicles (polymersomes). One important
potential application of amphiphilic block copolymers is as drug carriers, to help prevent the
deactivation of therapeutic agents such as proteins, antibodies, and nucleic acids during their travel
in the blood stream. Depending on the types of functional groups used and the external stimuli
present, different response mechanisms may come into play to control the behavior of these
systems including pH-responsiveness, thermosensitivity, redox-sensitivity, enzyme-sensitivity,
photosensitivity, and so on.
Polylactide has attracted much attention as a synthetic biomaterial in recent years. It is
approved for clinical uses because of its high biocompatibility and biodegradability. We now
describe the synthesis of a novel redox-sensitive bifunctional initiator for the metal-free ring
opening polymerization (ROP) of lactide. A series of redox-responsive amphiphilic block
copolymers combining chain segments of polylactide and either polylysine or poly(ethylene glycol)
were obtained using this bifunctional macroinitiator. The redox-responsive polymers were
characterized by 1H nuclear magnetic resonance (NMR) spectroscopy and gel permeation
chromatography (GPC). The polymers had a low PDI, and the Mn of the segments determined
from 1H NMR and GPC analysis were close to the target Mn values.
SS
OO
OH
O
ONH
ONH2
NH2
mn
SS
OO
OH
O
OHN
nO
O
Om
P-21
Complex Arborescent Copolymer Architectures by Self-assembly Aklilu Worku, Mario Gauthier
Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo,
Ontario N2L 3G1, Canada
Emails: aworku@uwaterloo.ca, gauthier@uwaterloo.ca
Arborescent polystyrene-graft-[poly(2-vinylpyridine)-block-polystyrene] copolymers have been
applied to the preparation of gold nanoparticles in our laboratory.1 The synthetic strategy used for
the compounds was an anionic grafting onto procedure, whereby the functionalization of a linear
or branched polystyrene (PS) substrate with acetyl groups was followed by grafting with anionic
“living” polystyrene-block-poly(2-vinylpyridine) chains. The resulting dendritic species had a
covalently bonded, layered structure with an inner shell of poly(2-vinylpyridine) (P2VP) chains.2
We now present a new method for the preparation of arborescent core-shell-corona structures,
namely polystyrene-graft-poly(2-vinylpyridine)-graft-poly(acrylic acid)-block-polystyrene, by
the self-assembly of arborescent polystyrene-graft-poly(2-vinylpyridine) with poly(acrylic acid)-
block-polystyrene through hydrogen bonding and electrostatic (weak acid-weak base) interactions.
This method is a very simple but effective way to prepare the polymeric templates in nearly 100
% yield. It involves anionic grafting for the synthesis of the arborescent polystyrene-graft-poly(2-
vinyl pyridine) substrates, atom transfer radical polymerization (ATRP) to synthesize the
poly(acrylic acid)-block-polystyrene copolymer, and mixing of the two components, either in
solution or in the solid state to prepare the core-shell-corona architectures. These complexes were
successfully loaded with tetrachloroauric acid (HAuCl4), and yielded nanomorphologies similar to
the systems obtained exclusively through anionic grafting.
References
1. Dockendorff, J.; Gauthier, M.; Mourran, A.; Möller, M., Arborescent AmphiphilicCopolymers as Templates for the Preparation of Gold Nanoparticles. Macromolecules 2008, 41 (18), 6621-6623. 2. Gauthier, M.; Li, J.; Dockendorff, J., Arborescent Polystyrene-graft-poly(2-vinylpyridine)Copolymers as Unimolecular Micelles. Synthesis from Acetylated Substrates. Macromolecules 2003, 36 (8), 2642-2648.
P-22
In situ synthesis of colloidal-stable Fe3O4 nanoparticles coated with multidentate blockcopolymer for MRI contrast agents
Wangchuan Xiao, Puzhen Li, Jung Kwon Oh*Department of Chemistry & Biochemistry, Concordia University, Montreal, QC, Canada
Magnetic resonance imaging (MRI) is a non-invasive imaging technique that produces
detailed images of the organs and tissues for disease detection, diagnosis and treatment
monitoring. Some MRI scans require contrast agents that shorten the relaxation times and
improve the visibility of internal body structures. Our group has developed multidentate
block copolymer (MDBC) strategy to stabilize superparamagnetic iron oxide nanoparticles
(SNPs) for effective MRI applications. We further demonstrated catechol-functionalized
MDBC (Cat-MDBC) strategy to stabilize to ultrasmall SNPs (USNPs, 3±0.5 nm) and
extremely small SNPs (ESNPs, 2 ± 0.4 nm) as a biocompatible and effective T1-weighted
MRI contrast agent (bright imaging) with prolonged colloidal stability in physiological
conditions. In order to further optimize the relaxation properties, we developed a facile
process to in situ fabrication of MDBC/SNPs with control core size in the range of 5-10 nm.
The results indicated that single nanocrystals or small nanoclusters can be produced by
changing the reaction parameters. The as SNPs are of high stability in PBS, saline as well as
different pH conditions, which facilitates to biomedical application.
a) Scheme of SNPs coated with MDBC and b) TEM image of MDBC/SNPs (dave=7.5 nm) by
in situ synthesis
P-23
Investigating the Dissolution Mechanism in Self-seeding of PFS Block
Copolymer Micelles
Qing Yu1, Gerald Guerin
1, Ian Manners
2, and Mitchell A. Winnik
1
1. Department of Chemistry, University of Toronto, Ontario, Canada, M5S 3H6
2. School of Chemistry, University of Bristol, Bristol, UK, BS8 1TS
Block copolymers self-assemble in selective solvents to form micelles. When self-assembly is
driven by the crystallization of the core-forming block, low curvature structures (lamellae or
fibers) are formed. Our group has studied what happens when a suspension of these PFS-PI
micelle fragments is heated in decane and allowed to cool. They form long uniform cylindrical
micelles, and the length of these micelles depends sensitively upon the heating temperature. This
process is called "self-seeding" and results from the fact that polymer crystal formation is not
uniform and results in different degrees of crystal perfection. Recently we found that the length
of the micelles obtained is also sensitive to polymer concentration, yielding shorter micelles at
higher concentration. To understand the mechanism of self-seeding of PFS block copolymer
micelles, PFS-PI micelles were examined in decane at different temperature in preliminary
studies using Diffusion Ordered Spectroscopy (DOSY). The signals due to the ferrocene group
can be seen only when the PFS block dissolves or becomes mobile. The results showed that
unimers diffuse rapidly in solution whereas the micelles diffuse more slowly. Therefore we used
DOSY to resolve signals from compounds based on diffusion coefficients, to monitor the
dissolution process as the samples are heated. In this way, we are able to distinguish unimers in
solution from mobile regions in the micelles. Other techniques such as transmission electron
microscopy (TEM) were also used to characterize the micelles and to study the dissolution
process.
P-24
Study of the Interactions of Pyrene-Labeled SNPs with Sodium Dodecyl Sulfate (SDS)
Qian (Jasmine) Zhang, Lu Li, Jean Duhamel
Institute for Polymer Research, Department of Chemistry, University of Waterloo, 200 University Avenue West, Waterloo, Ontario, Canada, N2L 3G1
Many hydrophobically modified water-soluble polymers (HMWSP) have interesting viscoelastic properties in aqueous solution that have found applications in numerous industries. The viscoelastic properties of the HMWSPs can be adjusted further by adding a surfactant to the solution which interacts with the polymer and promotes the formation of a polymeric network. The HMWSPs used in this study were water-soluble starch nanoparticles (SNPs) that were hydrophobically modified with the hydrophobic dye pyrene to yield pyrene-labeled SNPs (Py-SNPs). The Py-SNPs were then placed in the presence of the surfactant sodium dodecyl sulfate (SDS) and the interactions between the Py-SNPs and SDS were characterized. The formation of pyrene excimer between an excited and a ground-state pyrene was strongly affected by the SDS concentration. The ratio of the fluorescence intensity of the excimer over that of the monomer, namely the IE/IM ratio, was determined from the analysis of the steady-state fluorescence spectra. The IE/IM ratio represents the efficiency of pyrene excimer formation and it was monitored as a function of SDS concentration. Furthermore, time-resolved fluorescence decays were acquired to quantitatively determine the fraction of pyrene pendants of Py-SNPs which were aggregated as a function of surfactant concentration. Hydrophobic interactions between Py-SNPs and SDS were found to depend strongly on the pyrene content and SDS concentration. In aqueous solution, the Py-SNPs generated pyrene aggregates due to the hydrophobicity of the pyrene labels and the pyrene aggregates resulted in efficient excimer formation. This aggregation was disrupted by addition of SDS to the Py-SNP dispersions. As a result, the mode of pyrene excimer formation changed from direct excitation of pyrene aggregates at low SDS concentration to diffusive encounters between an excited and a ground-state pyrene at high SDS concentration. These results demonstrated that the hydrophobic interactions between pyrene labels in Py-SNPs were effectively disrupted by the presence of SDS.
P-25
Lanthanide-Containing PMMA Microspheres for Bead-Based Assays on Mass
Cytometry
Guangyao Zhao, Jianbo Tan, Mitchell A. Winnik*
Department of Chemistry, University of Toronto, Toronto, Ontario, Canada, M5S 3H6
Email: mwinnik@chem.utoronto.ca
Abstract: Bead-based assays based on flow cytometry have been widely used for quantitative
measurement of serum biomarkers, yet their application in the field of mass cytometry is still in a
proof-of-concept stage. Previously our group synthesized lanthanide-containing polystyrene
microspheres as bead supports for bead-based assays by mass cytometry. However, their surface
stabilizer hindered attachment of bioaffinity agents. To overcome this problem, we prepared
lanthanide-containing poly(methyl methacrylate) (PMMA) microspheres by a photoinitiated
RAFT dispersion polymerization with a macro-RAFT agent as the surface stabilizer. The macro-
RAFT agent was a copolymer of acrylic acid (AA) and oligo(ethylene glycol) methacrylate
(OEGMA). OEGMA provided colloidal stability for the PMMA microspheres in aqueous media
while AA provided surface functional groups for bioconjugation. Lanthanide ions were
incoporated into PMMA microspheres via copolymerization of MMA and small LnF3
nanoparticles bearing polymerizable surface ligands. We covalently attached streptavidin (SAv)
onto the surface of those PMMA microspheres and used three different methods to quantify the
biotin binding capactiy of SAv-labeled PMMA microspheres. Then we developed a sandwich-type
bead-based immunoassay by using those lanthanide-containing PMMA microspheres as bead
supports. We selected human IgG as the target analyte, as well as mouse IgG and rabbit IgG as
interfering species, to test the specificity of this bead-based immunoassay. We first used a
conventional fluorescent reporter, fluorescein-labeled Neutravidin (NAv), to examine the output
of the bead-based assay by confocal microscope. Then we used NaYF4@SiO2 nanoparticles
conjugated with NAv as a mass reporter and examined the output of the assay by transmission
electron microscopy (TEM). Both methods showed that our assay can specifically detect the target
analyte human IgG.
P-26
Approaches to the formation of nanofibrillar hydrogels based on
uniform PFS rod-like micelles
Hang Zhou1, Yijie Lu1, Meng Zhang1, Gerald Guerin1*, Ian Manners2*, Mitchell A.
Winnik1*
1. Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, ON, M5S 3H6
2. School of Chemistry, University of Bristol, Bristol UK, BS8 1TS
Nanofibrillar hydrogels are three-dimensional water-swollen networks formed by
the association or entanglement of fiber-like nano-structures. The mechanical properties,
biological activity and applications of these hydrogels are strongly influenced by their
intrinsic fibril nature. And one important factor of the system is the length of the building
block fibers.
Polyferrocenyldimethylsilane (PFS) block copolymers (BCP) can form fiber-like
micelles where the crystallisable PFS block serves as a core-forming block in a selective
solvent for the complementary block. Using the seeded growth protocol, in which one adds
a concentrated solution of unimer to a suspension of micelle seed fragments, we are able
to obtain uniform micelles. The length of the micelles is determined by the ratio of the
amount of unimer added to the amount of seeds initially present. Thus we set out to
synthesize PFS BCPs with a thermo-responsible corona to create dispersions of uniform
nano-fibers in water and investigate their behaviour as a function of concentration and
temperature.
PFS-b-poly(N-isopropylacrylamide) and PFS-b-poly(oligo-ethylene glycol
methacrylate) were selected as potential candidates. We first prepared micelles of
controlled lengths by seeded growth in alcohol solvents and characterized them by
multiangle light scattering and transmission electron microscopy. Then we studied the
methods to re-disperse the as-prepared micelles of different lengths in water and the
possibility of hydrogel formation upon temperature elevation above the LCST of the
corona chains. These well-defined structures will allow us to understand how fiber length
affects the properties of nanofibrillar hydrogels.
P-27
The 2016 edition of the High Polymer forum has been made possible by the financial support of the following organizations:
L’édition 2016 du Colloque Canadien sur les Polymères a été rendue possible grâce à la participation financière des partenaires suivants :
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