Surface morphology studies of multiblock and starblock copolymers of poly(.alpha.-methylstyrene) and poly(dimethylsiloxane)

Surface morphology and compositions of multiblock and starblock copolymers of poly(a-methyl styrene) (PMS) and poly(dimethyl siloxane) (PDMS) were investigated by cross-sectional transmission electron microscopy, angle- and energy-dependent ESCA, and infrared spectroscopy. The extent of surface segregation of PDMS was determined for multiblock and starblock copolymers to depth of 210{angstrom}. No surface excess was with high PDMS bulk concentrations (60 wt%) have a highly oriented lamellar morphology in the near air surface region, and the topmost air surface region (27 {angstrom}) is exclusively composed of PDMS. The PMS-PDMS block copolymers with lower PDMS bulk concentrations (40 wt%) have lesser or no domain orientation and the surface region includes detectable PMS.