SYNTHESIS AND THERMAL-PROPERTIES OF POLY(STYRENE-CO-4-METHYLSTYRENE) PRODUCED WITH SYNDIOSPECIFIC METALLOCENE CATALYSTS

Poly(styrene-co-4-methylstyrene) with a different content of comonomer units was prepared using the typical syndiospecific homogeneous catal ysts, i.e. eta-C5H5TiCl3 and eta-C-5(CH3)(5)TiCl3 combined with methyl aluminoxane (MAO). The eta-C-5(CH3)(5)TiCl3 catalyst gave the polymers with higher syndiotacticity. The monomer reactivity ratios indicated that the copolymers obtained with eta-C5H5TiCl3 and eta-C-5(CH3)(5)TiC l3 possessed random and slightly blocky structure, respectively. With an increase in the 4-methylstyrene comonomer units, the glass transiti on temperature of the copolymer increased linearly and the crystalliza tion temperature increased followed by a decrease in the melting point . (C) 1997 Elsevier Science Ltd.