EMULSIFIER-FREE SYNTHESIS OF MONODISPERSE CORE-SHELL POLYMER COLLOIDS CONTAINING CHLOROMETHYL GROUPS

Both the synthesis of m,p-trimethyl(vinylbenzyl)ammonium chloride (TMVBAC) and the synthesis of polymer colloids consisting of a shell of poly(vinylbenzyl chloride) grafted onto a well-defined, monodisperse poly(styrene-divinylbenzene) core are described. The preparation of the polymer latices consists of a sequence of different emulsifier-free emulsion polymerizations. First, monodisperse poly(styrene-divinylbenzene) seed latices: with 2,2'-azobis(2-amidinopropane) hydrochloride (AIBA . 2HCl) as cationic initiator, are prepared under batch conditions. These latices are used for the seeded polymerization of divinylbenzene (DVB), in order to synthesize monodisperse particles, with a well-defined spherical shape, which contain a sufficient amount of pendant vinyl groups for grafting of the vinylbenzyl chloride (VBC) monomer. After the graft polymerization, the chloromethyl groups can easily be modified with a postpolymerization reaction. As an example, the amination with trimethylamine (TMA) is described. (C) 1995 John Wiley & Sons, Inc.