Thermophoresis of thermoresponsive polystyrene–poly(N-isopropylacrylamide) core–shell particles

Abstract

We have investigated diffusion and thermodiffusion of thermosensitive core–shell particles (PS–PNIPAM) that consist of a poly(styrene) (PS) core and a poly(N-isopropyl acrylamide) (PNIPAM) shell by means of an optical beam deflection technique. The results are compared to recent literature values for linear PNIPAM chains and cross-linked PNIPAM microgel particles. The temperature dependence of the thermodiffusion coefficient of the core–shell colloids resembles that of the linear polymer and a number of other aqueous systems. It is significantly different from one of the crosslinked microgels.