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Markus AntoniettiMax Planck Institute of Colloids and Interfaces
Research Campus Golm, 14424 Potsdam
Ionic-Self Assembly (ISA)as a route towards (highly ordered,liquid
crystalline) nanomaterials with new architecture
Polyanion-Polycation complexes
precipitates from water,
easy synthesis
Strong and weak electrolytes behave differently
Classical in food and drug industry: ccoacervation
Polyanion-Polycation complexes:layer-by-layer technologies
G. Decher, H. Möhwald, F. Caruso
Polyanion-Polycation complexes:layer-by-layer technologies II
more complexstructures,
Inorganic shells
Polyelectrolyte Surfactant complexes
precipitates from water,
easy synthesis
- formation highly cooperative
- 1: 1 complex
- dissolves in organic solvents
- film forming
- no Tg and softening
Cooperativity of binding of PEs and surfactants
Polyelectrolyte complex films self-organize !
X-ray characterization of films
The product is a highly oriented lyotropic liquid crystalline polymer !
Na-PSS plus DTA-Br
Structure model
smectic SA-phase:
one flexible alkyl phase
one glassy ionic polymer phase
Structure of PAA with hydrophobic counterions
Conformation of single chains
Thermoplastic PE-Surf complexes by copolymerization
Choice of comonomers;
Different phases between 0 < x < 1
An interesting phase for the 40:60 mixture
Synchroton radiation
indexing according to cubic morphology, but in-plane oriented
The HPL phase
A polymeric molecular sieve film …
Fluorinated PE-Surfs: Coatings with ultralowsurface tension
Surface energies against C16H34:Wool 50 mN/mIron 50 mN/mPS 36 mN/mPDMS 22,8 mN/mPTFE 20,3 mN/mPDA-K12 12,7 mN/m
PE-Lipid complexes: high end rubbers
Mechanical characterization
λ = 500% !
A walk through data evaluation….
The κ-ι- diagram
Solution: the super-undulated phase
predicted by
Helfrich
Variation of lipid composition: increase ioniclipids
the corrugated lamellarphase
(a very close relative of the superundulated phase)
Complexes with oligopeptide
ox. Glutathione: a model peptide
Complexes organosolv, film forming !!
AFM characterization of glutathione-lecithine complexes
Structure Model
Complex structure withelements on threedifferent length scales !
Dye-Surfactant Complexes viaIonic Self-Assembly
Ionic Self-Assembly(ISA)
• Oligoelectrolyte-surfactant complexes
• Electrostatic interactions to drive theorganisation of matter
• Modular approach: multiple non-covalentinteraction strategy
π-Toolbox
• Shape-rigid, -defined tectonic units
Commercially available dyes
• Subphase formation?
N N
HO
NaO3S
SO3Na
N N
HO
NaO3S
SO3Na
N N
HO SO3Na
SO3Na
Orange G (OG) Crystal Scarlet (AR44) Bordeaux R (AR17)
N NNaO3S
HO SO3Na
SO3Na
Amaranth (AR27)
Binding?
• Binding studies – cooperativity?– Surfactant selective electrode– Titrino 720 / Dosimat 765 Combination– 20 °C ± 0.1 °
• Aggregate formation• Precipitated complex – 1:1 ratio?
– EA & ICP-AES
• Properties
Chem. Eur. J., in press
Structure?
• What is to be expected?– Crystalline / LC materials?– Lamellar / columnar / other phases?– Internal organisation of dye subphase?
N N
HO
NaO3S
SO3Na
N N
HO SO3Na
SO3Na
Crystal Scarlet (AR44) Bordeaux R (AR17) Pyrene tetrasulfonic acid (PTSA)
Structure(cont‘d)
• AR44 / AR 17 + single / double tail surfactants
Langmuir, accepted
-100 -50 0 50 100 150 200 250
Endo
>
Temperature (oC)
C18
C16
C14
C12
C10
0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6
140oC
85 oC
RT
Inte
nsity
S (nm-1)
• PTSA as a discotic system
Structure(cont‘d)
• Nano-phase separation that simple?• 3 Subphases a reality?
Nature surprises us!
Structure(cont‘d)
Single crystal analysisOG + C14TAB
Giant-Polyoxometallates
The „ferris wheel“ /A. Müller
Expanding modular approach
• Surfactant, codon, metallic species• Multiple interaction strategy
Modular Approach(cont‘d)
N
N
SO3-
SO3-
R
R
Na+
Na+
redgreenCuCl2
CH3HR
• Complexes based on stepwise noncovalent interactions
Camerel, Strauch, Antonietti, Faul, Chem Eur J, 2003
Mx+
4 surf
Cu(I) / Cu (II)
•Behaviour of copper species?
•Colour change with complexation
•Cu(II) to Cu(I) via complexation
•Heating of green Cu(II) complexes
•Films turn black
•Back to green via dissolution
Materials Properties(Cu(I) / C(II))
Oblique columnar phase
•CuCl2 / C24 / DiC18
Conclusion
• ISA is a facile route to organise matter• Coacervation, symplexes, LbL-structures• Objects turn into nanos, films and materials• Partly solubility in solvents• Multiple interaction strategy• Organisation of oligoelectrolytic π-systems• Exciting mechanical & optical properties• Structures and organisation into subphases