Nitroxide-mediated controlled/living free radical copolymerization of styrene and divinylbenzene in aqueous miniemulsion

The nitroxide-mediated controlled/living free radical copolymerization of styrene and divinylbenzene,using a polystyrene-TEMPO macroinitiator in aqueous miniemulsion and in bulk have been investigated. The crosslink densities were estimated based on the content of pendant vinyl groups as determined by H-1 NMR. Considerably lower crosslink densities were revealed in the miniemulsion than in the corresponding bulk system. The rate of polymerization in the miniemulsion increased with decreasing particle size, and was significantly higher than in bulk.