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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Organic/Inorganic Hybrid Coatings for Anticorrosion Applications
Maher M. Alrashed, Sadhan C. Jana, Mark D. Soucek
Polymer Engineering Department, The University of Akron, Ohio 44325, USA
The US Air Force (USAF) is one sector that experiences substantial impacts from corrosion as
a result of the need to run equipment in harsh conditions, such as high UV exposure, sea water,
humidity, thermal cycling, and mechanical stress. Chromate conversion coating (CCC) is an
effective coating for aircraft, however, chromium oxo anions (Cr6+) are confirmed by many health
centers and organizations as human carcinogens. In addition, to increase the lifetime of aircraft,
the aircraft body is commonly repainted periodically which adds environmental and economic
issues to the health concerns, thus forcing the US military to replace chromate conversion coatings.
Many systems and methods have been suggested to replace chromate conversion coatings; of
these, high solid content polyurethane/polysiloxane hybrid coatings are considered good
candidates. Although polyurethane/polysiloxane hybrid coatings have good optical and
mechanical properties, it provides less corrosion performance compared to chromate conversion
coating systems. Thus, this coating system needs further improvements or modifications.
The main goal of this study is to enhance the performance of polyurethane/polysiloxane hybrid
coating through implementation of passive modification concepts. This work includes the
introduction of a selective list of nanofillers with various aspect ratio and structure such as
graphene oxide, carbon nanotubes and layered silicate clay. The influence of nanofiller types,
loading, and surface functionality on coating barrier and physical properties will be investigated
1
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Title:
Highly Flexible Self-Assembled V2O5 Cathodes Enabled by Conducting Diblock Copolymers
Hyosung An,1 Jared Mike,1 Kendall A. Smith,2 Lisa Swank,2 Yen-Hao Lin,2 Stacy Pesek,2 Rafael
Verduzco,2* and Jodie L. Lutkenhaus1* 1Artie McFerrin Department of Chemical Engineering, Texas A&M University,
2Department of
Chemical Engineering, Rice University
Structural energy storage materials combining load-bearing mechanical properties and high
energy storage performance are desired for applications in wearable devices or flexible displays.
Vanadium pentoxide (V2O5) is a promising cathode material for possible use in flexible battery
electrodes, but it remains limited by low Li+ diffusion coefficient and electronic conductivity,
severe volumetric changes upon cycling, and limited mechanical flexibility. Here, we
demonstrate a route to address these challenges by blending a diblock copolymer bearing
electron- and ion-conducting blocks, poly(3-hexylthiophene)-block-poly(ethyleneoxide) (P3HT-
b-PEO), with V2O5 to form a mechanically flexible, electro-mechanically stable hybrid electrode.
V2O5 layers were arranged parallel in brick-and-mortar-like fashion held together by the P3HT-
b-PEO binder. This unique structure significantly enhances mechanical flexibility, toughness and
cyclability without sacrificing capacity. Electrodes comprised of 10 wt% polymer have unusually
high toughness (293 kJ/m3) and specific energy (530 Wh/kg), both higher than reduced graphene
oxide paper electrodes. Electrodes with commercial binder poly(vinylidene difluoride) shows no
remarkable improvement.
2
ABSTRACT
TOWARD SUSTAINABLE ASPHALTIC MATERIALS: AN INTEGRATED
INVESTIGATION OF BIOOIL MODIFIED ASPHALT
Iskinder Arsano, Kshitij C. Jha, Mesfin Tsige
A growing interest in investigating asphalt binders in the past few decades has been
driven by environmental and economic concerns that have entailed incorporation of bio
binders as a sustainable component in asphaltic processing. Additional issues of
processability such as phase separation of commonly used current binder alternates, for
example rubber crumbs, point towards the need for understanding the molecular level of
incorporation and its correlation to macro functionality. We have carried out molecular
dynamics simulations to study behavior of a class of biooils in an asphaltic matrix. In
particular, the orientation, packing, and conformation of asphaltic molecules in the
presence of the chosen family of biobinders have been quantified. The diffusion,
aggregation, and distribution of binders at a range of temperatures are correlated to
phase separation and binder bleeding. Given the enormous annual production of
asphaltic materials for paving and roofing applications a possible reduction in
processing temperature, through careful choice of costeffective and custom bio
binders, would have positive environmental impacts. Also, the very replacement of a
significant proportion of traditional binder by biooils allows for less use of bitumen,
which literally is the bottomofthebarrel product in heavy oil refineries.
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
3
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Soy-Based Resins and Fillers for Thermoset Composites
Paula Watt, Brinda Mehta, Abdala Bashir and COLEEN PUGH The University of Akron, Department of Polymer Science, Akron, OH 44325-3909, USA
In recent years, the development of green polymers for commercial applications such as coatings, adhesives, composites, and elastomers, has gained momentum. Advantages of converting soybean oil into green resins include: reduction of our dependence on oil reserves and increase the U.S. market share in the field of biorenewable polymers. Our approaches toward the synthesis of crosslinked polymers employ alkene- and alkyne chemistries based on the triglyeride, the major constituent in plant oil (Scheme 1). This poster will report high-bio content and low toxicity green resins derived from functionalized plant oils for various applications via the “ene” chemistry.1 The targeted properties of these green resins are Young’s modulus greater than 2000 MPa, high glass transition temperature of at least 120 °C, and more than 80% bio-content. The bio-content of the composites may also be increased by replacing mineral fillers with renewable biomass fillers.2 With a density of approximately 1 g/cm3 and a specific gravity of roughly 2.5 g/cm3, biomass fillers yield compounds at equivalent volume reinforcement with a 20-25% weight reduction compared to mineral filler. One issue with biomass filler is their hydrophilicity; this poster will present a variety of treatments that were studied to reduce the hydrophilic nature of the biomass precursor, especially thermal treatment. To evaluate the process and performance of the soy-filler compounds, dielectric analysis, squeeze flow rheometry and mechanical testing were employed.3,4
Scheme 1. Triglycerides are the major component of plant oils.
1. Pugh, C.; Watt, P.; Mehta, B., "Synthesis of Crosslinked Soybean Polymer Using Bismaleimides as Crosslinkers", USPCT 2014/54280 patent application filed 5 September 2014.
2. Pugh, C.; Watt, P.; Mehta, B., "Low Aromatic Content Bio-Mass Fillers for Free Radical and Ionic Cure Thermoset Polymers", USPCT 2015/16587 filed 19 February 2015.
3. Watt, P.; Pugh, C.; Rust, D., "Soy Based Fillers for Thermoset Composites”, ACS Symposium Series, Vol. 1178: Soy-Based Chemicals and Materials, R. Brentin ed., pp. 265-298; web publication date 23 December 2014.
4. Watt, P.; Pugh, C., "Studies to Determine Critical Characteristics of Thermally Treated Biomass Fillers Suitable for Thermoset Composites", Polymers from Renewable Resources 2015, 6, 1-24.
α-Linolenic acid
Linoleic acid
Oleic acid
4
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Control of wetting behavior of Si nanoparticles in PCHD-‐based diblock copolymers by tuning the graft chain stiffness. Kamlesh Bornani1, Balaka Barkakaty2, Bradley Lokitz2, Jimmy W. Mays1 and S. Michael Kilbey II1 1. Department of Chemistry, University of Tennessee, Knoxville, TN 37966 2. Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831 Email: [email protected] or [email protected] The use of grafting of polymers onto nanoparticles (NPs) to control their dispersion in a polymer matrix, represents a powerful way to control nanocomposite properties. While systems based on flexible polymer grafts have been studied extensively, systems based on semi-flexible polymers have been less studied, despite the impact local restrictions in chain conformation have on structure and dynamics. In our efforts to experimentally examine the role of chain flexibility on dispersion in polymer-grafted nanocomposites, we exploit the tunable flexibility of poly(1,3-cyclohexadiene) (PCHD), which allows chain microstructure (ratio of 1,4/1,2 linkages between consecutive monomers) to be manipulated without changing the monomer type. TGA and FTIR results indicate successful tethering of chains onto the NPs, with reaction conditions dictating grafting density of chains. The role of graft density and the relative molecular weight of matrix and graft chains on NP dispersion will be described along with parallel studies exploring the behavior of grafted chains comprising PCHD having 70/30 microstructural ratio, which increases chain stiffness.
5
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Nonlinear Mechano-Optical Behavior Of Phenylalanine-Based Poly(Ester Urea): Local Order in Amorphous Polymers
Keke Chen, J. Yu*, G. Guzman, S. Shams, M. Becker*, M. Cakmak Polymer Engineering Department
*Polymer Science Department The University of Akron
The mechano-optical behavior of melt-compressed amorphous phenylalanine-based poly(ester urea) (PEU) films was studied in their rubbery state under uniaxial deformation. The study focused on the effect of different diol chain length within PEU chemical structure, and was carried out by a real-time measurement system that can capture true stress, true strain and real-time birefringence during stretching. When subjected to deformation at low temperatures above Tg, materials exhibit photoelastic behavior contributed by the initial glassy component as segment-segment contact dominates. At higher temperatures above Tg, PEU with relatively shorter diol chain length shows the liquid-liquid (Tll) transition at about 1.06 Tg (K), in which the material transforms from a “liquid of fixed-structure” to a “true liquid” state and the initial photoelastic behavior disappears.
The effect of hydrogen bonding on the physical properties of PEUs was also studied. Fourier transform infrared spectroscopy (FTIR) was used to characterize the distribution of hydrogen bonds in PEU polymers as a function of temperature. The FTIR spectra indicates that the strength of hydrogen bonding diminishes with increasing temperature. In the case of PEUs with the longest diol chain length, integration of the area associated with N-H stretching region exhibits a linear dependence of temperature. However, the integrated area of N-H stretching region changes with temperature in three stages for PEU with shorter diol chain length.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Latex particles improved mechanical property in self-healing multilayer
polyelectrolyte film
Xiaoyu Cui
The lifetime of a film can be lengthened with the capacity of self-healing, which is
the ability of a material to repair mechanical damage. Water enabled self-healing of
polyelectrolyte multilayers is achieved by the systems that grow via the inter-diffusion
of polyelectrolyte chains. But poor mechanical property of the fabricated self-healing
materials limit the current and future application. Here, self-healing multilayer
polyelectrolyte film based on branched poly(ethyleneimine) (BPEI), poly(acrylic acid)
(PAA) and latex particles is prepared by layer-by-layer (LBL) self-assembly technique.
The BPEI/PAA/latex self-healing multilayer polyelectrolyte film not only shows self-
healing ability at high humidity, but also possesses good mechanical properties. The
self-healing ability of these films originates from the ability of BPEI and PAA to flow
and recombine in the presence of water. And the latex particles play a role in enhancing
the mechanical properties of the films. It is promised to expand the application of the
self-healing multilayer polyelectrolyte films.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Synthesis, Characterization and Mechanical Properties of
Physically Cross-linked Gels
Dibyendu Debnatha, R. A. Weiss b, and Coleen Pugh a
Departments of Polymer Sciencea and Polymer Engineeringb
The University of Akron
Akron, Ohio 44325-3909
Abstract: Chemically crosslinked gels typically have a low toughness because of inefficient
energy dissipation. Increasing the amount of covalent crosslinks improves the stiffness of the gel
but makes it brittle. Gels that are physically crosslinked are comparatively tougher due to better
viscoelastic energy dissipation produced by non-covalent, polar, and ionic interactions.1,2 In
addition, they are processable and can be molded into desired shapes, unlike covalently
crosslinked gels. We achieved hydrophobically modified hydrogels (HPMHs), in which the
hydrophobic groups act as physical crosslinking sites. These HPMHs show a dramatic increase in
the storage modulus (G’) and the loss modulus (G”) compared to conventional physical hydrogels.
The strength of HPHMs increases with increasing concentration of the hydrophobic species and
decreases with increasing hydrophilic monomer content in the polymer backbone.3 However, the
swelling ratio increases with decreasing hydrophobic content. The HMHs we obtained are stable
till 200 oC. Nevertheless, The HPMHs also show thermoresponsive behavior in the swollen state.
References:
1. Ajayaghosh, A.; George, S, J. J. Am. Chem. Soc. 2001, 123, 5148–514. 2. Sun, J. Y.; Zhao, X.; Illeperuma, W. R. K.; Chaudhuri, O.; Oh, K. W.; Mooney, D. J.; Vlassak,
J. J.; Suo, Z. Nature 2012, 489, 133-136. 3. Hao, J.; Weiss, R. A.; Macromolecules 2011, 44, 9390–9398.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Copper metallopolymers with variable mechanical properties by changing metal ion coordibation Travis C. Green, Anton O. Razgoniaev, Alexis D. Ostrowski. Department of Chemistry and Center for Photochemical Sciences, Bowling Green State University, Bowling Green, OH 43403, USA Transition metal-ligand interactions give a way to modify the mechanical properties and assembly of metallopolymers. Our group is interested in synthesizing systems of organic-inorganic hybrid metallopolymeric materials that show a dependence of mechanical properties on interactions between a polymer metal-binding termini-ligand and a metal ion. In the work presented here we prepared two metallopolymers by mixing hydrogenated poly(ethylene-co-butylene) terminated with Schiff-base metal binding moieties and copper (I) an copper (II) metal ions to create viscoelastic materials. By means of UV-Vis titrations we established 1:1 stoichiometry between the polymer and the copper metal center and a tetrahedral coordination environment or both copper (I) and copper (II)-based metalloplymers. We found that copper (I) and copper (II) metallopolymers showed different mechanical properties within the same coordination environment. The crossover point between storage modulus and loss modulus for the Cu(I)-metallopolymers was lower than for Cu(II)-metallopolymer. Current efforts are aimed at determining the structure-property relationships in these materials to understand how metal coordination geometry and bond length ultimately influence the mechanical properties of the bulk metallopolymer materials.
9
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Strengthening polymer thin films with cellulose nanocrystals (CNCs)
Nanofillers in thin polymer films offer unique advantage to potentially modify the film's thermal,
electrical and mechanical properties due to the high surface area to volume ratio and intrinsic
property change at the nanoscale. However for optimum property enhancement, the challenge
also lies in controlling the stability of these polymer thin films from nanofiller aggregation. In
this regard, CNCs are susceptible to aggregation by strong inter- and intra-molecular hydrogen
bonding between individual nanorods. We demonstrate tailored reinforcement of polymer films
by CNC via surface chemistry modification and controlled CNC distribution that strengthen the
particle-polymer interactions and system compatibility. Specifically, we optimize the synergistic
reinforcing effect of anisotropic CNC nanofillers in block copolymer thin films which can act as
ideal nanostructured templates to selectively sequester and organize fillers. Good control of CNC
dispersion within the homopolymer and block copolymer matrix is achieved by surface
functionalization and polymer grafting, maximizing the interfacial contact area, and allowing for
a uniform stress distribution for efficient load transfer to the CNCs. To this end, we examine the
morphology of the internal nanostructure and CNC distribution through high-resolution
microscopy and x-ray scattering analysis techniques.
Authors/Affiliations:
1. Danielle Grolman, The University of Akron, [email protected]
2. Chelsea Davis, National Institute of Standards and Technology, [email protected]
3. Jeffrey Gilman, National Institute of Standards and Technology, [email protected]
4. Emily Cranston, McMaster University, [email protected]
5. Alamgir Karim, The University of Akron, [email protected]
10
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Nonlinear Rheology of Oligomeric Ionomers: Shear-Thickening and Shear-Thinning Behavior of Sulfonated Polystyrene Melts
Chongwen Huang†, Quan Chen‡, Ralph H. Colby‖, R.A. Weiss†*
†Department of Polymer Engineering, University of Akron, Akron, OH 44325 ‡State Key Laboratory of Polymer Physics and Chemistry, Changchun
Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun
130022 China ‖Department of Materials Science and Engineering,
The Pennsylvania State University, University Park, PA 16802
Shear thickening behavior, which is often observed for associating polymer
solutions, was recently reported for ionomer melts1. In order to better
understand the mechanism of shear thickening in these melts, the nonlinear
rheological behavior of oligomeric sulfonated polystyrene ionomers (SPS) with
different degrees of sulfonation and different alkali metal cations were
measured at a variety of temperatures using steady shear. When the
Weissenberg number, Wi , defined as the product of applied shear rate and the
characteristic relaxation time of the ionic associations, approaches unity, shear
thickening was observed, but only for samples with a sulfonation degree close
to the gel point2, which is defined when each chain has on average one ionic
group. Below the gel point, only shear thinning behavior was observed, and
above the gel point, melt fracture occurred. The magnitude of shear thickening
increases with the decrease of temperature, molecular weight of the PS
precursor and the increase of ionic strength of the metal cation, ~ /q a , where
q and a are the charge and radius of the cation, respectively.
1 Weiss, R. A.; Zhao, H. J. Rheol. 2009, 53, (1), 191.
2 Chen, Q.; Huang, C.; Weiss, R. A.; Colby, R. H. Macromolecules 2015, 48, (4), 1221-1230.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Comb-Like Polycarboxylate Superplasticizers:
A Structure-Property Relationship Study
Ali Javadi and Mark D. Soucek*
Department of Polymer Engineering, University of Akron, Akron, USA
Correspondence to: M. D. Soucek; E-mail: [email protected]
Abstract
Superplasticizers (SPs) are an important class of chemical admixtures designed to adjust the
workability of cements. Comb-like polycarboxylate-ether based superplasticizers (PCEs) have
exceptional water-reducing property, which makes them perfect candidates as water reducers in
the manufacturing of concrete. It seems that the charged backbones are selected to adsorb
through electrostatic interactions with surfaces while the uncharged side chains are chosen to
induce steric hindrance among adsorbed layers [1, 2]. Although some research groups have
already studied the effects of the side chain density of PCEs on cement paste, there are still
several unsolved problems when using SPs in cementitious materials. The main aim of the
present study was to link the structural parameters of PECs with their performance in
cementitious systems in order to better understand the interaction mechanisms of PCEs with
cementitious materials. Therefore, we synthesized a series of well-defined PCEs 1−6 having
systematically different side chain density. The interactions between the synthesized PCEs and
cement pastes as well as the origin of repulsion forces caused by these systems were investigated
by the measurements of flow characteristics, adsorption, and zeta potential. Rheological
measurements were performed to obtain a better understanding for the cement paste rheology.
Adsorption analyses data were obtained to quantify the amounts of SPs involved in the steric and
electrostatic stabilization of the fresh cement pastes. The impact of adsorbed PCEs on
interparticle forces was monitored by recording the zeta potential of cement pastes.
References
1. Marchon, D., et al., Molecular design of comb-shaped polycarboxylate dispersants for
environmentally friendly concrete. Soft Matter, 2013. 9(45): p. 10719-10728.
2. Yoshioka, K., et al., Role of Steric Hindrance in the Performance of Superplasticizers for
Concrete. Journal of the American Ceramic Society, 1997. 80(10): p. 2667-2671.
12
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Effect of pigmentation and polysiloxane to alkoxysilane end capped epoxy Minjung Joo and Mark D. Soucek
Department of Polymer Engineering, The University of Akron
Inorganic-organic hybrid coatings are widely studied due to their advantages such as better toughness and corrosion protection. Alkoxy functional silanes are silicon-based chemicals that contain two types of reactivity, inorganic and organic in the same molecule and the modification of bisphenol A epoxy is tried with different structures. The use of pigments is for the purpose of color, hiding and the cost. Due to their incompatibility or high surface area, pigments easily aggregate and use of polysiloxane and alkoxiysilane with them can be influential on its distribution, which could change the final properties. The objective of this study is to investigate the interaction of pigmentation and inorganic-organic hybrid coatings.
13
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Plant Oil-Based Coatings with Fast Drying/Curing and Low Yellowness
Deep Kalita, Sneha Mecheri Subash, Bret Chisholm*
Department of Coatings and Polymeric Materials, North Dakota State University, Fargo, ND 58102
Email: [email protected]
Abstract
Till date most of the articles that talks about application of paints concerns about the binding media. However, there is
only few studies that carried out to understand the aging behavior of these binders that obtained from renewable resources prior to
the wide spread availability of petrochemicals. The plant oil-based poly(vinyl ether)s (POVEs) has been synthesized and their use
as a binder for artist paint has been investigated. The study provide several advantages over traditional drying oils in coatings.
POVEs can be produced from semi-drying oils, such as soybean oil, Palm oil that dry/cure faster than drying oils. POVEs can be
produced that have both dramatically lower color and faster drying than drying oils. The viscosity of POVEs can be easily tailored
by tailoring molecular weight without affecting other properties. In addition to tailoring viscosity, drying/curing time can be tailored
by tailoring plant oil-based monomer composition.
14
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
To Explore the Nature of Mechanical Stress Arising from
Large Deformation of Polymeric Glass
Xiaoxiao Li, Jianning Liu, Panpan Lin and Shi-Qing Wang*
Department of Polymer Science, University of Akron
It has been over 10 year since Kramer urged the polymer community to clarify the
nature of strain hardening in ductile deformation of polymer glasses.1 After extensive
studies, it is generally agreed that the increase of stress with strain in the post-yield
regime is dominantly plastic due to enhanced inter-segmental interactions.2 In this
work we carry a series of stress relaxation experiments from both pre-yield and post-
yield regimes at different temperatures to show that a significant amount of stress from
ductile deformation can be of intrasegmental origin, supporting the recent molecular
pictures3 regarding yielding and brittle-to-ductile transition of polymer glasses.
This work is supported, in part, by a NSF grant (DMR-EAGER-1444859).
1. Kramer, E. J. Journal of Polymer Science Part B: Polymer Physics 2005, 43, 3369-3371.
2. Hoy, R. S. Journal of Polymer Science Part B-Polymer Physics 2011, 49, 979-984.
3. Wang, S.-Q.; Cheng, S.; Lin, P.; Li, X. J. Chem. Phys. 2014, 141, 094905.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Thermo-Mechanical Property Comparison of Graphene Oxide
Nanocomposites Fabricated through Stereolithography and
Solution Casting
Jill Manapat*, Joey Mangadlao, Rigoberto Advincula
Department of Macromolecular Science and Engineering
Case Western Reserve University
Graphene oxide (GO) has been studied widely because of its superior properties,
particularly its high mechanical strength as nanocomposite filler. Traditional methods of
preparing GO nanocomposites do not offer much flexibility as to the shape of the final
product. On the other hand, additive manufacturing (i.e. 3D printing) has been exploited by
various industries because of its capability to produce complex geometries that are otherwise
impossible through subtractive manufacturing methods. However, a common problem
associated with 3D-printed parts is their poor mechanical property, which has limited its use
primarily as a rapid prototyping technique. Many researchers have studied 3D printing of GO
using methods such as Fused Deposition Modeling (FDM) and Stereolithography (SLA). Few
studies, however, have compared the thermo-mechanical properties of GO nanocomposites
fabricated using SLA and traditional methods. For this study, the thermo-mechanical
properties of GO nanocomposites produced from SLA and and solution casting is compared.
Characterization techniques include tensile and compressive tests for mechanical property
determination, differential scanning calorimetry (DSC) to observe thermal behavior of the GO
nanocomposite, rheological measurements to better understand effects during processing,
and scanning electron microscopy (SEM) for surface morphology and fracture analyses. In the
long run, this study may aid in converting the SLA 3D printing process from rapid prototyping
to rapid manufacturing.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Melt-spinnable Precursors for Carbon Fiber Production
Gregory C. Miller,a,c Jianger Yu,b,c R. M. Joseph,a,c Shreya Roy Choudhury a,c, Donald G. Baird,b,c J. S. Rifflea,c*
aDepartment of Chemistry, bDepartment of Chemical Engineering and the cMacromolecules and Interfaces Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061
Abstract
The feasibility of melting spinning polyacrylonitrile (PAN) with plasticizers has been investigated for decades,
but a process for doing so has yet to be commercialized because PAN begins undergoes a cyclization reaction at a
temperature prior to the melting temperature. In this investigation, the thermal and time-dependent behavior of
poly(acrylonitrile-ran-methyl acrylate) (PAN-MA) with various plasticizers is explored. Differential scanning
calorimetry (DSC) indicates that various plasticizers such as ethanol, N,N-dimethyl formamide, N-methyl pyrrolidone,
acetonitrile and adiponitrile are capable of sufficiently depressing the melt temperature of PAN-MA thus making the
melt spinning process feasible. The time-dependent rheological stability experiments show that plasticized PAN-MA
maintains a stable viscosity without significant degradation and crosslinking for a sufficient period of time below 180
℃. Gel fraction determination of films subjected to various temperatures, isothermal DSC, and FTIR are also utilized
to further investigate the conditions necessary to induce the crosslinking reaction in PAN-MA.
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Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Mechanical and Rheological Study of Blend Anion Exchange Membranes
George Amobi Ozioko, Gigi George, Matthew Liberatore*
Department of Chemical & Environmental Engineering, the University of Toledo
Anion exchange membranes (AEM) are solid polymer electrolytes that facilitate ion transport in fuel
cells. Interest in the development of AEM with high ionic conductivity for its applications
within the alkali fuel cell industry has grown considerably in recent years. AEM fuel cells
benefit from increased kinetics in an alkali media allowing more complex fuels than hydrogen
to be utilized. AEM fuel cells also have the potential to use non-platinum catalysts, which
could lead to lower costs. However, the development of mechanically robust thin films is
challenging.
In this study, membranes will be synthesized by blending polymers to create AEMs.
Polystyrene and poly (vinyl benzyl chloride) will be blended and the mechanical
characterization studies performed to determine the blend stability. In addition to measuring
conductivity, mechanical property measurements under different hydration levels and
humidity cycling will be used to predict a membrane’s lifetime. The local dynamics confined
within the individual polymer membranes need to be adequately understood in order to
predict the influence of microstructure on the performance and stability of the blend
membranes. The blends will also be analysed using various morphological study techniques,
such as DSC, TGA, XRD, SAXS and FTIR.
18
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Mechanical Properties of Poly(ethylene glycol) Reinforced
by Abaca Nanocrystals and 3D Printed via SLA
Napolabel Palaganas 1,2
, Joey Mangadlao 2, Al Christopher De Leon
2,
Katrina Pangilinan 2, Jerome Palaganas
1,2, and Rigoberto Advincula
2
1 Mapua Institute of Technology, Intramuros, Manila, Philippines
2 Department of Macromolecular Science and Engineering, Case Western Reserve University,
Cleveland, Ohio, USA 44106
Abstract
The operational framework for printing three-dimensional nanocomposite hydrogel consisting of
poly(ethylene glycol) and nanocellulose (specifically abaca nanocrystals) via stereolithography
apparatus is presented. Poly(ethylene glycol) has been extensively studied due to its
hydrophilicity and biocompatibility. However, this material lacks attractive mechanical
properties that are required by many applications. Nanocrystals, known to be hydrophilic and
biocompatible as well, exhibit inherent stiffness with a density of around 1.6 g/cm3 thus
promoting their potential to provide high-performance reinforcement in polymeric composites.
The combination appears to be promising because the strength of abaca nanocrystals can easily
be incorporated into the polymeric matrix by suspending them in the cross-linked network. This
mechanical reinforcement stems from the strong hydrogen bonds within and between the
cellulose chains. It is expected that the current system will allow significant improvement in the
mechanical properties of the conventional polyethylene glycol, which may be attributed to the
uniquely efficient energy dissipation through the reversible interactions between the nanocrystals
and the covalent cross-links of polyethylene glycol. One of the important considerations to attain
optimum results, the dispersion of the nanocrystals is regarded to be homogeneous at
concentrations below 1.5% v/v. Over this level, the nanoparticles tend to aggregate locally. Once
achieved at optimum volume loading of nanocrystals, a good balance between elasticity and
toughness likewise between fracture stress and fracture strain will strengthen the conventional
polyethylene glycol hydrogel at least threefold. The experimental values of the modulus are
believed to exceed the predicted moduli of Guth-Gold model simply to indicate assurance of
notable enhancement. Successful printing of three-dimensional figures will provide
manufacturers a good test bed for failure analysis and testing the limits of product prototypes
using hydrogel material.
19
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Polymeric additives to the base oils of hydrocracking residue
Nelya Razyapova
Gubkin Russian State University of Oil and Gas Department of Chemistry and Technology of Lubricants and Chemmotology
Moscow, Russia, 119991
Abstract
The base oil fractions of hydrocracking residue 410-510 °C provides a motor oil grade 5W-30 with high performance levels. The properties of the oils such as 5W-30 API SL (Afton additive package with a concentration of 10.0 wt.%, SV 260 thickener at a concentration of 1.0wt.% and 623 Afton depressant at 0.5 wt.%) are shown in Table 1.
Table 1. Oil quality indicators such as 5W-30 API SL.
Indicator Test Methods Value Kinematic viscosity at 40 °C, mm2/s GOST 33 57.82
Kinematic viscosity at 100 °C, mm2/s GOST 33 10.76
Viscosity index GOST 25371 180
Four-ball machine (diameter of the wear scar,
mm) GOST 9490 0.4
Pour Point, 0 °C GOST 20287 -35
MRV
(Mini-RotatyViscometer) ASTM D4684
1574 (-15 °C)
3040 (-20 °C)
6848 (-25 °C)
13308 (-30 °C)
43509 (-35 °C)
CCS
(Cold-Cranking Simulator) ASTM 5293
772 (-15 °C)
1373 (-20 °C)
2406 (-25 °C)
4229 (-30 °C)
9079 (-35 °C)
For the dewaxed oil fraction of exhaust 410-510°C has better properties package consisting of 10% by weight of 9387 (X) Afton Hitec, 1.0 wt.% SV-260, 0.5 wt.% 623 Afton depressant.
When adding a pour point depressant Infinium V-387 in an amount of 0.5 wt. % instead of 623 Afton, pour oil 5W-30 temperature is reduced to -45 °C. Other low-temperature properties of the oil were also improved. 20
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
CNT-phosphonium ionic liquid nanofluids: interface and rheology study
Author: Sayali Satam
Carbon nanotubes (CNTs) are used as additives to improve thermal, mechanical, electrical and
tribological properties of the composites. However, CNTs have a strong tendency to aggregate because
of their nanosize and high surface energy. CNTs can be chemically modified to achieve good dispersion
in the matrix, but this can damage its structural properties. Therefore, their physical modification using
surfactants is preferred. Ionic liquids (IL), which are room temperature salts, form well dispersed matrix
with CNTs because of cation-π or Vander Waals interactions between the two. In this study, solid-liquid
interaction between MWCNTs and a phosphonium IL is investigated. IL-CNT composite is characterized
using DSC, FTIR and TEM to analyze the IL-CNT interface behavior. Detailed information about
microstructure of nanofluids is studied from the rheological properties of these composites at different
concentrations.
21
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Graded and Heterogeneous Materials using Digital Light Processing Additive Manufacturing
Gregory I. Peterson,† Johanna Schwartz,† Di Zhang,‡ Ben Weiss,‡ Mark A. Ganter,‡ Duane W.
Storti,‡ and Andrew J. Boydston† †Department of Chemistry and ‡Department of Mechanical Engineering, University of
Washington, Seattle, WA 98195 United States
Graded materials, where a property or composition of the material varies spatially
throughout the object, are common in nature, with examples including teeth, bone, tree trunks, and
the squid beak. However, manufacturing graded materials often involves time intensive or
expensive methods. Simple, versatile, and efficient methods for doing so are still needed. In our
manuscript, we demonstrate graded and heterogenous materials prepared using a vat
photopolymerization technique (i.e. 3D printing). Using a commercial resin and 3D printer with a
digital light processing (DLP) projector, graded materials were obtained by varying the intensity
of light within the sliced image stacks used for printing. The material properties of the printed
objects were selectively tuned by controlling the light intensity, resulting in a threefold increase in
elastic modulus and offset compressive yield strength of the material. Furthermore, the impact of
heterogeneous and graded materials was demonstrated by changing the anisotropic bending
properties of a rectangular 3D object and by increasing the strain-to-break of octet truss structures
to a value greater than that achieved by homogenously increasing the light intensity. Variation in
levels of crosslinking is a potential cause of the differences in mechanical properties seen at
different light intensities. Current research involves confirming this theory, as well as expanding
on the versatility of this process towards use in other materials.
22
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Non-Chromate Flexible Binders for Aerospace Applications
Author : Masoud Sobani
Coating systems utilize two mechanisms to protect against corrosion damage of the substrates.
First mechanism, a coating system functions as a barrier keeping the electrolyte from contacting the
metallic substrate. This is referred to as corrosion prevention since the electrolyte does not contact the
metallic substrate the corrosion cell is not established, therefore no corrosion can occur. Second
mechanism, if the coating system, or barrier, is compromised, corrosion will occur but corrosion inhibitors
in the primer retard ion flow in the electrolyte slowing down the corrosion process. This is corrosion
control. The best primer the Air Force has used on large aircraft was a chromate polysulfide primer
purchased to MIL-P-87112. The primer utilized a sealant chemistry which possessed superior flexibility.
The polysulfide is a two-part primer coating with 2.7% chromate content. Prior to 1998 the polysulfide
primer was applied to the complete outer mold line of large bodied aircraft. The implementation of more
stringent emission regulations, stated in the 1998 National Emission Standards for Hazardous Air
Pollutants (NESHAP) created under the 1990 Clean-Air Act, restricted the use of the polysulfide primer. As
a result, DoD applies the polysulfide primer on corrosion prone areas of the aircraft which classifies this
use as a specialty coating and there are no restrictions for specialty coatings. In this work, mercaptan-
terminated polysulfides (G112) from Akzo-Nobel reacted with epoxy resin (Epon 828) from Shell. Amine
hardeners (Jeffamine T-403) from Huntsman were also used. The epoxy and polysulfides were added and
mixed together at 500 revolutions per minute for 2 hours at 50 degrees Celsius. After storing at ambient
conditions for 2 weeks, the amine hardener was added and mechanically stirred for 2 minutes.
Afterwards, the coatings were cast onto aluminum sheets and/or later tested for impact resistance,
thermal, dynamic mechanical, and adhesion properties.
23
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Thermoset Rubber Reinforced by Oligo--alanine
Xin Tan, Joseph Scavuzzo, Li Jia* and Gary Hamed *
Department of Polymer Science, University of Akron, Akron
Abstract
The present project aims to use oligo--alanines covalently attached to rubbers as the crosslinker
and filler[1]. The oligo--alanine motifs self-associate into -sheets through cooperative multiple
intermolecular hydrogen bonds to achieve physical crosslink[2]. The self-associated oligo--alanines
-sheets phase separate from hydrocarbon polymers even at a few percent of the total weight to form
crystalline b-sheet domains. The crystalline domains further act as fillers. Upon stretching, the sheets may
slide against each other, and/or the hydrogen bonds can break and re-form. Each serves as an energy
dissipation mechanism. The above design of novel supramolecular crosslinker/filler system is expected to
produce the following practical results: reduced rolling resistance, improved wet-skid resistance, and
improved strength and crack resistance. Consequently, the tires produced with this technology are
expected to be fuel efficient without compromising safety.
R
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-sheet of oligo--alaninestacked -sheetscrystalline -sheet domainsin a rubber matrix
References
[1] Jia, L.; Scavuzzo, J. A.; Kennedy, J. P. “Thermoplastic elastomers containing an oligopeptide hard
component”, PCT/US13/37974
[2] J. Masamoto, K. Sasaguri, C. Ohizumi, H. Kobayashi. J. Poly. Sci. Part A-2. 1970, 8, 1703.
24
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
poly(ethylene glycol) (PEG) based Engineering ion-containing block copolymers
Meng Wang (School for Engineering of Matter, Transport & Energy at Arizona State University)
Block copolymers are polymers that consist of covalently linked chains of different
homo-polymers. Ion-containing block copolymers are a class of polymers with unique
and fascinating properties, which make them relevant in many applications including
water purification, colloid stabilization, and amphiphilic drug carrier systems. Ionenes are
ion-containing polymers that have quaternary nitrogen atoms in their main chain, which
imparts unique properties to nanocomposites because of the electrostatic interactions.
Segmented ionenes offer improved mechanical properties compared with nonsegmented
ionenes and resemble polyurethanes in terms of mechanical properties. By making
poly(ethylene glycol) (PEG) based ionenes, we can control the mechanical properties by
changing the PEG molecular weight.
25
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Impact of hydrogen bonding on dynamics of hydroxyl-terminated
polydimethylsiloxane
Kunyue Xing,1 Sabornie Chatterjee,1 Tomonori Saito,3 Catalin Gainaru,1,2Alexei P. Sokolov1,3
1 Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, United States
2Fakultät für Physik, Technische Universität Dortmund, 44221 Dortmund, Germany
3Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831,
United States
Dielectric spectroscopy, rheology, and differential scanning calorimetry were employed to
study the effect of chain-end hydrogen bonding on the dynamics of hydroxyl-terminated
polydimethylsiloxane. We demonstrate that hydrogen bonding has a strong influence on both
segmental and slower dynamics in the systems with low molecular weights. In particular,
the decrease in the chain length leads to an increase of the glass transition temperature,
viscosity, and fragility index, at variance with the usual behavior of non-associating
polymers. The supramolecular association of hydroxyl-terminated chains leads to the
emergence in dielectric and mechanical relaxation spectra of the so-called Debye process
traditionally observed in monohydroxy alcohols. Our analysis suggests that the hydroxyl
terminated PDMS oligomers may associate in brush-like or chain-like structures, depending
on the size of their covalent chains. The effective length of the linear-associated chains was
estimated from the rheological measurements.
26
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
27
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
STRUCTURE-PROPERTYRELATIONSHIPSOFDUALMETHACRYLATEDEPOXIDIZEDSUCROSESOYATE(DMESS)
ArvinZ.Yu,JonasM.Sahouani,DeanC.WebsterDepartmentofCoatingsandPolymericMaterials,NorthDakotaStateUniversityThermosetswereproducedfromfree-radicalcuringofnovelbio-basedresin,methacrylatedepoxidizedsucrosesoyate(MESS)[1].Thethermosetsshowedhighglasstransitiontemperature(Tg)andgoodmechanicalproperties,however,theviscositywashigh.ThisissuewascircumventedbyfurtherfunctionalizationoftheMESStodualmethacrylatedepoxidizedsucrosesoyate(DMESS).Nevertheless,thethermosetsproducedfromDMESSwereverybrittle.Tomaintainlowviscosityandimproveductility,replacementofsomemethacrylategroupswithacetategroupswashypothesized.Thesynthesisremainedasaone-potprocessinvolvingthesequentialslowadditionoftwoanhydridesmixedpriortoaddition.TheacetylatedDMESS(MAcetSS)wascharacterizedusingFouriertransforminfraredspectroscopy(FTIR),protonnuclearmagneticresonancespectroscopy(1H-NMR),gelpermeationchromatography(GPC),andviscositymeasurements.Formulationsweremadeusingvaryingamountsofstyreneandfree-radicallycuredusingcommerciallyavailableperoxyestersasinitiators.TheextentofcurewasdeterminedbygelcontentusingSoxhletextractionandconfirmedusingFTIR.Thethermalandmechanicalpropertieswereevaluatedusingthermogravimetricanalysis(TGA),dynamicmechanicalthermalanalysis(DMTA),andtensiletesting.Reference:1. Yan,J.;Webster,D.C.GreenMaterials2014,2,132-143.
28
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Directed Assembly of Nanoparticle Filled Polymer Thin Films
Ren Zhang,1 Bongjoon Lee,2 Michael R. Bockstaller,2 Christopher M. Stafford3, Jack F. Douglas3 and Alamgir Karim,*1
1 Department of Polymer Engineering, University of Akron 2 Department of Materials Science and Engineering, Carnegie Mellon University
3 Materials Science and Engineering Division, NIST Directed self-assembly (DSA) of nanoparticle (NP) filled polymeric thin films is important for
various potential technological applications such as photonic device and nanowire fabrication.
Fabrication of well-designed nanoparticle assembly structures requires a fine control of
processing parameters which need to be properly optimized. Herein, we introduce two facile
methods towards realizing tunable NP structures involving a dispersion of polymer-grafted
nanoparticles in a homopolymer matrix. In one method, the application of zone-annealing with
soft-shear creates unidirectionally aligned highly anisotropic nanoparticle arrays in a chemically
dissimilar homopolymer matrix with tunable aspect ratio. In another method, we demonstrate
soft confinement patterning can generate high-density nanoparticle domains with well-controlled
size, shape and location in both chemically identical and dissimilar homopolymer matrices. Both
methods are applicable to versatile nanoparticle-polymer combinations and adaptable for roll-to-
roll production.
29
Poster Presentations: Mechanical – Rheological Properties of Polymers and Composites
12th National Graduate Research Polymer Conference 2016 | College of Polymer Science and Polymer Engineering at The University of Akron
Chain networking in polymeric glasses revealed
by molecular dynamics simulation
Yexin Zheng, Mesfin Tsige, Shi-Qing Wang
The Maurice Morton Institute of Polymer Science and Engineering
Department of Polymer Science, University of Akron, Akron, OH 44325
Abstract
Based on the Kremer-Grest model for entangled polymer melts, we demonstrate how
the mechanical response of a polymer glass depends critically on the chain length.
After quenching two melts of very different chain lengths (500 beads per chain and 50
beads per chain respectively) as well as their mixtures into deeply glassy states, we
subject them to uniaxial extension. Our MD simulations show that the glass of long
chains undergoes stable necking after yielding whereas the system of short chains is
unable to neck and breaks up after strain localization. During ductile extension of the
polymer glass made of long chain significant chain tension builds up in the load-bearing
strands (LBSs). These results are consistent with the recent molecular model 1and
demonstrate the role of chain networking.
1. Wang, S.-Q.; Cheng, S.; Lin, P.; Li, X. The Journal of Chemical Physics 2014, 141, (9), 094905.
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