A Novel Approach to Prepare Core/Shell Polymer Latex Particles with High Sulphonate Contents

摘要

Crosslinked x-P(St-MAA) seed latex was first prepared via soap-free emulsion copolymerization of styrene(St) and methyl methacrylic acid(MAA) with divinyl benzene as crosslinker and ammonium persulfate as initiator, and x-P(StMAA)/x-P(St-NaSS) core/shell latex particles were then synthesized through a novel seeded emulsion copolymerization of St and sodium styrene sulphonate(NaSS) in the presence of water-soluble crosslinker N,N'-methylene bisacrylamide(BAA) using oil-soluble 2,2-azobis isobutyronitrile as initiator. TEM observation indicated that narrow dispersed core/shell latex particles were obtained, and element analysis showed that NaSS unit content in the whole particle and in the shell reached 22.8 wt% and 51.2 wt%, respectively.