LIGHT-SCATTERING AND FOURIER-TRANSFORM INFRARED STUDIES ON THE MISCIBILITY OF BLENDS OF POLY(VINYL METHYL-ETHER) AND STYRENE-CONTAINING COPOLYMER

The miscibility of blends containing poly(vinyl methyl ether) (PVME) and one of three different styrene/(styrene derivative) copolymers was investigated by light scattering and Fourier-transform infra-red (FTi.r.) spectroscopy. For this purpose copolymers of styrene with o-methyl-, p-methyl- or m-methylstyrene were synthesized by radical polymerization. The copolymer compositions were fixed at 10% and 20% (by weight) in the monomer feed ratio. The light scattering studies revealed that all the blends showed lower critical solution temperature (LCST) behaviour. In the FTi.r. results, the relative intensity of the 1080 cm-1 peak was greater than that of the 1 108 cm-1 peak, due to the COCH3 bond of PVM E, in all the blends studied in this work. It is concluded that all the blends are miscible at room temperature over the entire concentration range studied, and the miscibility of the styrene/(styrene derivative) copolymers with PVME decreases in the order poly (styrene-co-o-methylstyrene) > poly (styrene-co-p-methylstyrene) > poly (styrene-co-m-methylstyrene).