EMULSIFIER-FREE SYNTHESIS OF MONODISPERSE CORE-SHELL POLYMER COLLOIDSCONTAINING CHLOROMETHYL GROUPS

Both the synthesis of m,p-trimethyl(vinylbenzyl)ammonium chloride (TMV BAC) and the synthesis of polymer colloids consisting of a shell of po ly(vinylbenzyl chloride) grafted onto a well-defined, monodisperse pol y(styrene-divinylbenzene) core are described. The preparation of the p olymer latices consists of a sequence of different emulsifier-free emu lsion 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. T hese latices are used for the seeded polymerization of divinylbenzene (DVB), in order to synthesize monodisperse particles, with a well-defi ned spherical shape, which contain a sufficient amount of pendant viny l groups for grafting of the vinylbenzyl chloride (VBC) monomer. After the graft polymerization, the chloromethyl groups can easily be modif ied with a postpolymerization reaction. As an example, the amination w ith trimethylamine (TMA) is described. (C) 1995 John Wiley & Sons, Inc .