Macromolecules, Vol.45, No.23, 9258-9266, 2012
Catalytic Chain Transfer Mediated Autopolymerization of Divinylbenzene: Toward Facile Synthesis of High Alkene Functional Group Density Hyperbranched Materials
A facile and highly reproducible autopolymerization method, mediated by catalytic chain transfer, for the synthesis of hyperbranched materials with high alkene functional group density is reported. The rapid autopolymerization of divinylbenzene at 150 degrees C in the absence of any catalytic chain transfer agent was demonstrated to result in the formation of highly cross-linked networks/gels in less than 10 min. Exploitation of the extremely high chain transfer coefficient of bis[(difluoroboryl)diphenylglyoximato]cobalt(II) delayed gelation and produced good yields of high molecular weight hyperbranched divinylbenzene in under 1 h on a multigram scale. Gas chromatography was employed to monitor the levels of conversion over the course of the reaction. The materials produced were characterized by GPC, MALLS, and viscometry.