Dresden 2011 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 34: Poster: Elastomers and Gels
CPP 34.4: Poster
Mittwoch, 16. März 2011, 17:00–19:00, P2
Switching Behavior of Thermoresponsive Poly(2-oxazoline) Copolymers — •Sebastian Jaksch1, Joseph Adelsberger1, Anita Schulze4, Stephan Salzinger2, Stephan Huber2, Rainer Jordan2,4, Zhenyu Di3, and Christine M. Papadakis1 — 1TU München, Physikdepartment, Physik der weichen Materie, Garching — 2TU München, Department Chemie, Lehrstuhl für Makromolekulare Chemie, Garching — 3JCNS-FRM II, Garching — 4TU Dresden, Department Chemie, Professur für Makromolekulare Chemie, Dresden
Amphiphilic copolymers in aqueous solution exhibit a wide range of morphologies ranging from micellar and other colloidal structures to hydrogels at high concentrations. Poly(2-oxazoline)s represent a very attractive class of materials as their properties can be tuned from hydrophilic via thermoresponsive to hydrophobic by changing the side group from methyl (MOx) over iso-propyl (iPrOx) and n-propyl (nPrOx) to nonyl (NOx) with the backbone being rather polar. We present here measurements on different chain architectures.
Temperature-dependent SANS measurements were carried out at KWS 2/FRM II around the lower critical solution temperature (LCST) for PiPrOx homopolymer and gradient copolymers with NOx monomers in dilute solution in D2O. PiPrOx is soluble with swollen chainconformations below the LCST. With increasing amount of NOx monomers, the chainconformation becomes more compact. The chain size grows when the LCST is approached from below and follows a power law, indicating a critical phase transition. In all cases large aggregates are present as well.