Polymerization of styrene by diphenylzinc-additive systems. Part IX. New experiments with Ph2Zn-Met-MAO systems

The combined systems diphenylzinc-metallocene-methylaluminoxane (Ph2Zn-Met- MAO) have proved able to induce styrene polymerization, producing polystyre ne with a variable content of stereoregular polymer. The tacticity of the o btained polymer is strongly dependent on the nature of the metallocene and on its molar ratio toward diphenylzinc (Met/Ph2Zn). The stereoregular polym er was syndiotactic according to its crystalline melting temperature T-m, C -13 NMR spectrum, and insolubility in boiling butanone. (C) 1999 Society of Chemical Industry.