交联剂对无皂P(MMA-EA-MAA)种子聚合乳胶粒成孔的影响

采用完全无皂种子乳液聚合技术合成了粒径窄分布的P(MMA-EA-MAA)乳胶粒,通过对上述胶乳进行碱处理,制备出了具有空腔结构和多孔结构的聚合物乳胶粒,研究了交联剂的种类和用量对聚合过程、胶粒特性及胶粒结构形态的影响.结果表明,体系中加入交联剂后,单体转化率都有不同程度的提高;随交联剂用量的增加,乳胶粒粒径略有减小,交联剂用量较高时,乳胶粒粒径分布加宽;二乙烯基苯(DVB)的交联效率稍高于双甲基丙烯酸乙二醇酯(EGDMA);不加入交联剂及EGDMA用量低于0.5%时,处理后乳胶粒呈空腔结构,加入DVB及EGDMA用量高于1.0%时,处理后乳胶粒呈多孔结构,并且乳胶粒体积增量随交联剂用量的增加而减小.

INFLUENCES OF CROSSLINKING AGENT ON THE GENERATION OF VOIDS AND MULTIHOLLOW INSIDE SOAP-FREE P(MMA-EA-MAA) SEEDED LATEX PARTICLES

Narrow size distributed soap-free P(MMA-EA-MAA) latex particles with different crosslinking degree were synthesized by seeded emulsion polymerization of methyl methacrylate(MMA),ethyl acrylate(EA) and methacrylic acid(MAA),and voids and multihollow latex particles were obtained after undergoing alkali treatment.Influences of kind and amount of crosslinking agents on the polymerization,particle properties and particle morphology were investigated.Results showed that the monomer conversion increased slightly in the presence of the crosslinking agents.The size of particles decreased slowly as the amount of crosslinking agent increased,and the size distribution of the particles broadened at a higher amount of crosslinking agent.Divinyl benzene(DVB) was more effective than ethyl glycol dimethyl methacrylate(EGDMA) to make polymer crosslinked.During alkali treatment process,void latex particles can be obtained when no DVB or less than 0.5 wt% of EGDMA was used,while multihollow structure was generated when DVB or more than 1.0 wt% of EGDMA was introduced.The volume expansion of the particles decreased with increasing the amount of crosslinking agents.