SURFACE EFFECTS ON POLYMER BLENDS AND BLOCK-COPOLYMER MELTS - THEORETICAL CONCEPTS OF SURFACE ENRICHMENT, SURFACE-INDUCED PHASE-SEPARATION AND ORDERING

Surfaces have a profound effect on the structure and related properties of multiphase polymeric materials; such as polymer mixtures and block copolymer mesophases. In particular, phase transitions in the bulk (unmixing, microphase separation, etc.) may be complemented by surface-induced transitions (formation of wetting layers, surface-directed spinodal decemposition, surface-induced ordering). This review gives a brief introduction to the phenomenological theories of such phenomena, emphasizing the simplest approach based on Flory-Huggins-de Gennes free energy functionals and associated Monte Carlo simulations. More sophisticated theories and recent experiments are mentioned briefly.