钯的二亚胺催化剂催化1-辛烯乳液聚合

Emulsion homo- and copolymerization of 1-octene catalyzed by palladium(Ⅱ)-α-diimine

以钯的二亚胺为催化剂,在乳液体系中催化1-辛烯均聚合及1-辛烯与丙烯酸甲酯(MA)共聚合。通过光散射分析仪、差示扫描量热仪、凝胶渗透色谱仪、核磁共振谱仪测定了聚合物的粒径、熔点、相对分子质量,表征了其结构。结果表明:该催化剂在乳液体系中可以催化1-辛烯均聚合及1-辛烯与MA的共聚合;聚合物相对分子质量可达2.30×104以上,且相对分子质量分布(1.0～2.0)较窄,共聚物中MA与1-辛烯的摩尔比高达1.0∶4.5;均聚物的支化度(81.8个/1 000 C)和共聚物的支化度(112.8个/1 000 C)均较高;共聚物为半结晶型共聚物,其玻璃化转变温度为-57℃,熔点为83℃。

Homopolymerization of 1-octene and copolymerization of 1-octene with methyl acrylate （MA） were carried out in emulsion systems by using palladium（Ⅱ）-a-diimine as catalyst. The particle diameter, melting point, relative molecular mass and structure of the polymers were studied by light scattering, differential scanning calorimetry （DSC）, gel permeation chromatography （GPC） and hydrogen nuclear magnetic resonance （1H-NMR）. The results indicate that the catalyst can catalyze homopolymerization of 1-octene and copolymerization of 1-octene and MA in emulsion systems. The resultant polymers have relative molecular mass up to 2.30×10^4 and narrow relative molecular mass distribution in the range of 1.0-2.0. The molar ratio of MA to 1-octene in the copolymer reaches 1.0 ： 4.5. The degree of branching is relatively high, 81.8/1 000 C in the homopolymer and 112.8/1 000 C in the copolymer. The copolymer is a semierystalline one with glass transformation temperature of -57 ℃ and melting point of 83℃.