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Influence of pH and Ionic Strength on Self- A ssembly of Double Hydrophilic Block Copolymer with Oppositely Charged Ionic Surfactant. Miroslav Štěpánek, Mariusz Uchman and Karel Procházka. Department of Physical and Macromolecular Chemistry Faculty of Science, Charles University
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Influence of pH and Ionic Strength on Self-Assembly of Double Hydrophilic Block Copolymer with Oppositely Charged Ionic Surfactant Miroslav Štěpánek, Mariusz Uchman and Karel Procházka Department of Physical and Macromolecular Chemistry Faculty of Science, Charles University Prague, Czech Republic ISPE 2010, 14–16 November 2010, Shanghai, China
Outline double-hydrophilic block copolymer with a weak polyelectrolyte block: poly(methacrylic acid)-block-poly(ethylene oxide) (PMAA-b-PEO) surfactant: N-dodecylpyridinium chloride (NDPCl) Bronich, T.K.; Kabanov, A.V.; Kabanov, V.A.; Yu, K.; Eisenberg, K. Macromolecules1997, 30, 3519: PMAA186-b-PEO176/NDPCl in alkaline solutions • PMAA-b-PEO/NDPCl complexes in alkaline aqueous solutions and influence of ionic strength on the interaction between PMAA-b-PEO and NDPCl • PMAA-b-PEO/NDPCl complexes in acidic aqueous solutions and transfer of the complexes from alkaline solutions to acidic solutions Stoichiometric ratio: ISPE 2010, 14–16 November 2010, Shanghai, China
Interaction between PMAA-b-PEO and NDPCl 1H NMR, D2O, c = 5.37 mg/mL, b = 1 PFG 1H NMR, diffusion coefficient of NDPCl in as a function of b NOESY 1H NMR, 0.05 M Na2B4O7, b = 2 ISPE 2010, 14–16 November 2010, Shanghai, China
Formation of PMAA-b-PEO/NDPCl complexes in alkaline solutions 0.05 M sodium tetraborate, c = 1 mg/mL Static light scattering, q = 0° DLS, q = 90° Electrophoretic mobility ISPE 2010, 14–16 November 2010, Shanghai, China
Structure of PMAA-b-PEO/NDPCl complexes in alkaline solutions 0.05 M sodium tetraborate SAXS, c = 5 mg/mL TEM, c = 1 mg/mL b = 1 b = 2 ISPE 2010, 14–16 November 2010, Shanghai, China
Influence of ionic strength: Light scattering measurements in 1 mM, 10 mM and 50 mM sodium tetraborate, c = 1 mg/mL Gyration radius Rg-to-Rh ratio ISPE 2010, 14–16 November 2010, Shanghai, China
Influence of ionic strength: ITC measurements in 1 mM, 10 mM and 50 mM sodium tetraborate NDPCl without the copolymer (b calculated for c = 1 mg/mL) c = 1 mg/mL ISPE 2010, 14–16 November 2010, Shanghai, China
PMAA-b-PEO/NDPCl complexes in acidic solutions Solution A: PMAA-b-PEO (c = 1 mg/mL) in 0.05 M sodium tetraborate Solution B: NDPCl in 0.1 M HCl Experiment: 0.8 mL B + 0.2 mL A DLS, q = 90° scattering intensity, q = 90° ISPE 2010, 14–16 November 2010, Shanghai, China
Transfer of the complexes from alkaline solutions to acidic solutions Titration of the complex (b = 1, c = 0.1 mg/mL) in 0.05 M sodium tetraborate with phosphoric acid DLS, q = 90° pH-dependence of scattering intensity and gyration radius ISPE 2010, 14–16 November 2010, Shanghai, China
Conclusion two types of PMAA-b-PEO/DPCl complexes alkaline solution: electrostatic interaction PEO PMAA NDPCl b≥ 1 b< 1 b = 0 acidic solution: hydrophobic interaction ISPE 2010, 14–16 November 2010, Shanghai, China
Acknowledgment The authors thank to... Faculty of Science, Charles University, Prague Zdeněk Tošner (NMR) Institute of Macromolecular Chemistry, Academy of Sciences of CR, Prague Miroslav Šlouf, Jiřina Hromádková (TEM) Borislav Angelov (SAXS) TU Berlin Michael Gradzielski (consultations, providing access to ITC and z-potential measurements) Funding Institutions Czech Science Foundation (Grant P208/10/0353) Ministry of Education of CR (Long Term Research Project MSM0021620857) ...and to you for your kind attention! ISPE 2010, 14–16 November 2010, Shanghai, China