不饱和端基超支化聚合物/丙烯酸酯共聚乳液的研究

利用Si—H加成反应制得了以CC为端基的超支化含硅聚合物,并将其与丙烯酸酯类单体进行乳液共聚,对聚合反应机理及所得聚合物的性能进行了测试分析.结果表明,含有大量CC端基的超支化含硅聚合物能与丙烯酸酯类单体稳定聚合,制得了平均粒径小于100nm高度交联的乳胶粒子.共聚物的红外光谱证实,超支化聚合物的不饱和端基已全部反应,形成了以超支化聚合物为多臂交联点的交联型乳胶粒子.随聚合体系中超支化聚合物用量的增加,乳液聚合反应速率增大,乳胶粒粒径减小,共聚物热稳定性显著提高.

STUDY OF EMULSION POLYMERIZATION OF ACRYLATES WITH A HYPERBRANCHED POLYMER TERMINATED BY UNSATURATED DOUBLE BONDS

A hyperbranched polymer terminated by unsaturated double bonds (HBS) was synthesized and applied in emulsion copolymerization of acrylic monomers,butyl acrylate and methyl methacrylate.The polymerization mechanism,properties of the copolymers and the influence of HBS on the crosslinking structure of copolymers were investigated.The results showed that the acrylates emulsion polymerization process in the presence of HBS was stable,and crosslinked latex particles with average diameter less than 100 nm were obtained.FT-IR measurements of the latex copolymers also showed that the unsaturated terminal groups of HBS are all accessible to polymerization without trapping inside the hyperbranched macromolecular structure,and thus,the polymer networks in which HBS act as multi-arms crosslink points come into being.The emulsion polymerization rate and thermal stablity of the latex copolymers increase,the latex particle size decreases with the increase in HBS content.