The molecullar weight dependence of the surface viscoelasticity function for the monodisperse PS (polystyrene) films has been investigated on the basis of SVM (scanning viscoelasticity microscope) measurement. In the case of Mn < 26.6K, the film surface is found to be in a glass-rubber transition state or a rubbery state, even at 293K. A depression of the surface Tg compared with that of bulk samples is explained in the basis of the surface localization of chain end groups. SIMS measurements revealed that chain end groups are enriched in the depth range from the outermost surface to Rg.
All Science Journal Classification (ASJC) codes