乳聚丁苯互穿网络型热塑性弹性体的制备

Preparation of thermoplastic elastomer using SBR latex interpenetrating network polymerization

以丁苯胶乳为种子乳液 ,苯乙烯、甲基丙烯酸甲酯、丙烯腈或它们的混合物为硬单体 ,用氧化还原引发体系 ,经种子乳液聚合法制备出复合乳液 ,絮凝干燥后所得互穿聚合物网络可热塑性反复加工。考察了硬单体的种类和用量、交联剂的种类及用量、反复加工次数对聚合物力学性能的影响 ,用透射电子显微镜观察了乳胶粒微观形态。结果表明 :用混合单体 ,聚合物力学性能较优 ,以35份St +MMA为第二单体制备的聚合物的扯断伸长率为400 % ,拉伸强度为9.3MPa ,300 %定伸应力为7.6MPa ,撕裂强度为73.9kN·m-1,邵尔A型硬度为84。

A new kind of core-shell latex with gradient distribution of hard polymer which based on SBR latex was synthesized through two stage emulsion polymerization in order to prepare interpenetrating polymer network. Styrene (St), methyl methacrylate (MMA), acrylonitrile (AN), one or two or three was selected as hard monomer and redox initiation system were used. The effects on mechanical properties and polymerization of hard monomers and crosslinker were studied. The morphology of the materials was determined by transmission electron microscopy that the latex particles appeared as core-shell structure with hard polymer gradient distributed. The mechanical properties of the SBR/P(St+MMA) interpenetrating polymer networks reached the tensile strength 9.3 MPa. The resulting materials were able to be reprocessed like thermoplastic elastomer.