SELF-ASSOCIATION VERUS INTERASSOCIATION IN HYDROGEN-BONDED POLYMER BLENDS .2. COMPARISON OF THEORETICAL AND EXPERIMENTAL MISCIBILITY WINDOWS FOR POLY(2,6-DIALKYL-4-VINYL PHENOL) BLENDS

Self-association and interassociation equilibrium constants determined from i.r. studies of miscible poly(2,6-dimethyl-4-vinyl phenol) (PDMV Ph) and poly(2,6-diisopropyl-4-vinyl phenol) (PDIPVPh) blends with pol y(n-butyl methacrylate) and an ethylene-co-vinyl acetate (EVA) copolym er are used to calculate theoretical miscibility windows for the homol ogous series of poly(n-alkyl methacrylate)s and the entire copolymer c omposition range of EVA copolymers. Miscibility gaps are predicted to increase significantly for analogous blend systems in the series PDIPV Ph > PDMVPh > poly(4-vinyl phenol). One factor contributing to this tr end is the steric hindrance of the 2,6-dialkyl substituents, which ser ve to reduce the relative strength of self-association versus interass ociation. Experimental i.r. studies of these blend systems corroborate the overall shape and size of the single phase region of the predicte d miscibility windows. Copyright (C) 1996 Elsevier Science Ltd.