负载钛系催化剂催化合成高反式丁二烯-异戊二烯共聚物

SYNTHESIS OF HIGH trans-1,4-BUTADIENE-ISOPRENE COPOLYMERS BY SUPPORTED TITANIUM CATALYSTS

采用负载钛系催化剂 [TiCl4 MgCl2 (i Bu) 3Al]催化丁二烯 (Bd) 异戊二烯 (Ip)共聚合 ,研究了单体配比、聚合温度、烷基铝浓度和催化剂浓度及单体浓度等对共聚合速率及共聚物特性粘数的影响 .结果表明 ,当单体配比中Bd (Bd +Ip)摩尔百分比≤ 2 0 % ,可制得高分子量的共聚物 .IR光谱分析及1 H NMR分析表明所得共聚物为高反式 1,4 结构 ,丁二烯单体单元的反式 1,4 含量大于 90 % ,异戊二烯单体单元的反式 1,4 含量大于 98% ,共聚物中丁二烯含量高于单体初始配比中的含量 .在一定的载钛量下 。

Butadiene(Bd) and isoprene(Ip) were copolymerized with TiCl4/MgCl2-Al(i-Bu)(3) catalyst system. The effect of polymerization conditions such as feed ratio, temperature, Al/Ti mole ratio, Ti/M mole ratio and comonomer concentration on catalytic efficiency and intrinsic viscosity of the copolymers was investigated in details. The DSC results indicated that the products with low butadiene feed ratio (f(1)(0) less than or equal to 20%) were copolymers. IR and H-1-NMR spectra analysis of the copolymers showed that the copolymers were mainly trans-1, 4-structure. Ip units of the copolymers had trans-1,4-contents above 98% and Bd units had trans-1,4-entents above 90% and copolymerization conditions had little effects on micro-structure of the copolymers. It was found that the reaction activity of Bd was greater than that of Ip.