Interfacial Segregation of Hyper-branched Polystyrene in Mixtures of Linear Component

Abstract

To study an effect of polymer architecture on surface segregation in polymer mixtures, concentration profile in films composed of hyper-branched polystyrene (HBPS) and deuterated linear polystyrene was examined along the direction normal to the surface by dynamic secondary ion mass spectroscopy. HBPS with two different end groups such as hydrogen and dithiocarbamate (HBPS-H and HBPS-DC) were used. While HBPS-H was preferentially segregated at both surface and substrate interface, HBPS-DC was partitioned only to the substrate interface. These results can be explained in terms of conformational entropic penalty and chain end localization at the surface.