Transition Behavior of Weakly Interacting PS-b-PMMA Films on Preferential Surfaces: A Direct Observation by GISAXS

摘要: The phase transitions for the films of a symmetric polystyrene-b-poly(methyl methacryltate) (PS-b-PMMA) on modified surface, like order-to-disorder transition (ODT) in weak segregation regime, was investigated by situ grazing incidence small-angle X-ray scattering (GISAXS). selective interactions at surface PS-brush substrate that favors preferential with PS component block copolymer enhance parallel orientation lamellar microdomains to film surface. This effect weakly interacting PS-b-PMMA leads gentle decrease temperature increasing thickness up 50L0 (lamellar period). We discuss this dependence temperatures surfaces terms χ between two components.