STUDY OF THE MISCIBILITY OF POLY(VINYL PYRIDINES) WITH POLY(VINYL ACETATE), POLY(VINYL ALCOHOL) AND THEIR COPOLYMERS

Miscibility of poly(4-vinyl pyridine) (P4VP) and poly(2-vinyl pyridine ) (P2VP) with poly(vinyl acetate) (PVAc), poly(vinyl alcohol) PVA and poly(vinyl acetate-co-alcohol) (ACA copolymers) has been investigated over a wide composition range. Differential scanning calorimetry (DSC) results indicate that P2VP is immiscible with PVAC, PVA, and their co polymers over the whole composition range. In turn, P4VP appears to be immiscible with PVAC and PVA, but miscible with some ACA copolymers i n certain range of composition. The P4VP-ACA phase diagram for differe nt copolymer compositions has been determined. The variation of the gl ass transition temperature with composition for miscible mixtures was found to follow the Gordon-Taylor equation, with the parameter kappa d ependent upon copolymer composition. FTIR analysis of blends reveal th e existence of specific interactions via hydrogen bonding between hydr oxyl groups and the nitrogen of the pyridinic ring, which appear to be decisive for miscibility. (C) 1994 John Wiley and Sons, Inc.