Berlin 2008 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

CPP: Fachverband Chemische Physik und Polymerphysik

CPP 29: Polymerphysics I

CPP 29.10: Vortrag

Donnerstag, 28. Februar 2008, 12:00–12:15, C 130

Structure investigations of thermo-sensitive triblock copolymers — •Amit Kulkarni¹, Kordelia Troll¹, Charles Darko¹, Christine M. Papadakis¹, Weinan Wang¹, Peter Müller-Buschbaum¹, Achille M. Bivigou Koumba², and André Laschewsky² — ¹Physikdepartment E13, TU München — ²Institute für Chemie, Universität Potsdam

Thermo-sensitive triblock copolymers consisting of a hydrophilic block, poly(N-isopropylacrylamide) (PNIPAM), and hydrophobic polystyrene end blocks, are expected to form physically cross-linked micellar gels in aqueous solution, which are swollen below the lower critical solution temperature (LCST) and collapsed above. They are of interest for a number of applications. We focus on the conformational change of the micellar shell as a function of temperature and the PNIPAM volume fraction. Three triblock copolymers with different PNIPAM volume fractions and three triblock copolymers having deuterated polystyrene blocks were studied by small angle X-ray scattering, small angle neutron scattering and dynamic light scattering with respect to the core-shell structure and swelling-deswelling of the shell. The non-deuterated triblock copolymers show the LCST at 31°C with micelles size of around 22 nm below collapse temperature and 17nm above.