Facile, versatile and cost effective route to branched vinyl polymers

Free radical one-step polymerisation of methyl methacrylate in the presence of a crosslinking comonomer and balancing levels of a chain transfer agent allow facile high conversion synthesis of polymers with a branched archite cture. Broad GPC curves have been obtained for these materials and branchin g has been demonstrated using GPC coupled with a triple detection system al lowing evaluation of g', the Zimm branching factor. In addition the bridgin g residues in branched polymers arising from use of an unsaturated crosslin king comonomer have been chemically cleaved to yield the linear oligomers o f much narrower molecular weight distribution that comprise the branched st ructure. The methodology promises to be generic, utilises only readily avai lable starting materials and holds out good prospects for providing branche d vinyl polymers on a technically useful scale at low cost. (C) 2000 Elsevi er Science Ltd. All rights reserved.