MISCIBILITY OF POLY(N-VINYL-2-PYRROLIDONE) WITH (METHYL-METHACRYLATE) (2-HYDROXYETHYL METHACRYLATE) AND (NORMAL-BUTYL METHACRYLATE) (2-HYDROXYETHYL METHACRYLATE) COPOLYMERS

The miscibility of poly(N-vinyl-2-pyrrolidone) (PVP) with (methyl methacrylate)/(2-hydroxyethyl methacrylate) (MMA/HEMA) and (n-butyl methacrylate)/(2-hydroxyethyl methacrylate) (BMA/HEMA) copolymers was studied. While PVP is immiscible with poly(methyl methacrylate), it is miscible with a MMA/HEMA copolymer containing 1.9 mol% of HEMA. PVP is immiscible with a BMA/HEMA copolymer containing 13.9 mol% of HEMA and its miscibility with a BMA/HEMA copolymer containing 17.4 mol% of HEMA is composition dependent. However, PVP is completely miscible with BMA/HEMA copolymers having HEMA contents of 20.9, 23.4 and 27.5 mol%. The results show that, as the size of the pendant ester groups becomes larger, the polymethacrylate requires the incorporation of a larger amount of HEMA to achieve miscibility with PVP.