Regensburg 2019 – wissenschaftliches Programm
CPP 25.48: Poster
Dienstag, 2. April 2019, 14:00–16:00, Poster B1
Mesoglobules in PNIPAM solutions: Influence of pressure — Bart-Jan Niebuur1, •Geethu P. Meledam1, Vitaliy Pipich2, Marie-Sousai Appavou2, Alfons Schulte3, and Christine M. Papadakis1 — 1TU München, Physik-Department, Garching, Germany — 2FZ Jülich, JCNS at MLZ, Garching, Germany — 3University of Central Florida, Orlando, U.S.A.
Poly(N-isopropylacrylamide) (PNIPAM) in aqueous solution forms mesoglobules upon heating through the cloud point, which are small and contain only little water. In contrast, at high pressure, much larger clusters are formed, which contain more water than at atmospheric pressure . We use very small angle neutron scattering at temperatures above the cloud point to elucidate the transition between low and high pressures. We find a sharp transition between small mesoglobules and large clusters with the transition pressure depending on temperature. We attribute the pressure-dependent behavior on mesoscopic length scales to the pressure-dependent hydration of PNIPAM.
1. B.-J. Niebuur et al., ACS Macro Lett. 6, 1180 (2017)