二(三氟乙酸)卤化钕催化体系中卤素对催化共轭双烯烃聚合的影响

摘要/Abstract

摘要： 众所周知,稀土配位催化剂用于共轭双烯的定向聚合,卤素是形成活性中心的必要条件之一。文献上对卤素在稀土催化剂中的作用曾有研究,但报导的都是非均相催化体系和三元催化体系。均相的二元催化体系中的卤素作用尚未见文献报导。鉴于从可溶性(CF₃COO)₂NdClEtOH-Et₃Al体系中分离出含卤素原子的活性体,研究卤素在该体系中的作用,对于活性催化剂的形成条件和催化聚合反应机制的了解都有意义。

Abstract: The effect of halogen atom in the (CF₃COO)₂NdX·EtOH-R₃Al (X:Cl, Br,I;R:Et,i-Bu) catalyst system on the polymerization of butadiene or isoprene has been studied. The results indicate that the catalyst containing halogen atom with higher eletro-negativity is more active. The intrinsic viscosities of polybutadiene and polyisoprene catalyzed with (CF₃COO)₂NdX·EtOH-Et₃Al system were found in the order of Br>Cl>I while that obtained with (CF₃ COO)₂NdX·EtOH-i-Bu₃Al system Cl>Br>I. The catalysts with different halogen lead to the microstructure change of the polymer obtained, but the active species of the catalyst system have little effect on the cis-contents of polymers.

李兴民, 金鹰泰, 李贵生, 孙玉芳, 欧阳均. 二(三氟乙酸)卤化钕催化体系中卤素对催化共轭双烯烃聚合的影响[J]. 应用化学, 1986, 0(2): 77-80.

Li Xingmin, Jin Yingtai, Li Guisheng, Shun Yufang, Ouyang Jun. EFFECT OF HALOGEN IN(CF₃COO)₂ NdX·Et0H-R₃ AI CATALYST SYSTEM ON THE POLYMERIZATION OF CONJUGATED DIENES[J]. Chinese Journal of Applied Chemistry, 1986, 0(2): 77-80.