双锂体系立构三嵌段聚丁二烯的研制

以双卤代烷烃取代型双锂齐聚物为引发剂,环已烷为溶剂,丁二烯单体一次加入,在聚合反应过程中加入极性添加剂,合成了1,2－1,4－1,2－立构三嵌聚聚丁二烯,并对双锂体系丁二烯聚合反应动力学及聚合物结构性能进行了研究。随着1,2－％的增加,聚丁二烯的无同结构含量逐渐减少,全同和间同结构含量逐渐增加,聚丁二烯的全同含量总是高于间同含量;与丁二烯均聚物相比,在1,2－％相近时,立构嵌段聚丁二烯具有更高的有规结构含量,全同和间同结构含量更高。

Studies on the synthesis of the stereo- triblock polybutadiene

The kinetic behaviours of the polymerization, the structures and the properties of the 1,2- 1,4- 1,2- stereo -triblock polybutadiene initiated by the dilithium initiator were investigated. The studies on the microstructure and sequential arrangement of 1,2- 1,4- 1,2- stereo - triblock polybutadiene showed that the content of the atactic structure decreased while the isotactic and syndiotactic structure increased gradually with the increase of the vinyl unit content in the polybutadiene. The content of the isotactic structure was always higher than that of the syndiotactic structure. It was found that the stereo - triblock polybutadiene had the higher content of the tactic structure than the general homo - polybutadiene under the approximate vinyl unit content.