Dresden 2006 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
CPP: Chemische Physik und Polymerphysik
CPP 12: POSTER Colloids, Nanoparticles and Self-Organizing Systems
CPP 12.10: Poster
Tuesday, March 28, 2006, 17:00–19:00, P3
pH-Responsive mixed Blockcopolymer/Surfactant Aggregates — •Thomas Hellweg1, Guillermo Orts Gil1, and Helmut Schlaad2 — 1TU Berlin, Stranski-Lab. (ER1), Strasse des 17.Juni 112, 10623 — 2MPI-KGF, 14424 Potsdam
Amphiphilic block copolymers can self-assemble into various ordered mesophases. The symmetry and stability of the microstructure depends intimately on chain size and chemistry as well as physical variables such as temperature. The present work is related to the study of three Poly(styrene)-Poly(L-lysine) diblock copolymers in aqueous surfactnat and organic solvents, by Dynamic Light Scattering and Atomic Force Microscopy. The study is focussing on the following points: the characterization of the structures in solution, their stabilization using surfactants, the random coil-$∖alpha$-Helix transition in the polypeptide block and the influence of added substances on the system. The results show: the affinity of each polymer to the solvent depends strongly on the block length ratio. The pH induced transition from the random coil to $∖alpha$-helix seems to be between 10-11 and induces a significant decrease in the translational diffusion coefficient. The addition of water or benzoic acid to the organic solutions induces structural changes.