Investigation of the cononsolvency effect on micellization behavior of polystyrene-b-poly(N-isopropylacrylamide)

The unusual aggregation behavior of poly(N-isopropylacrylamide)-based amphiphilic block copolymers was investigated by a combination of dynamic and static laser light scattering, AFM, and 1H NMR. The results revealed that PS-b-PNIPAM always forms large micelle aggregates in the transition process from an organic solvent to water due to the cononsolvency effect of PNIPAM. The cononsolvency effect of PNIPAM can be avoided to obtain classical micelles with PS29-b-PNIPAM27 in acetone–water at low temperatures (below 20 °C).

AFM images of PS29-b-PNIPAM27 micelles formed in the THF–water system without dialysis of THF and after dialysis of THF.Figure optionsDownload as PowerPoint slide