Influence of external nitrogen-containing donors on polymerization behavior of neodymium-based cis-1,4-polybutadiene rubber

外加含氮给电子体对钕系顺丁橡胶聚合行为的影响

Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outstanding high cis-1,4-unit selecti-vity is hypothetically originated from the presence of 4 f orbitals,that can participate in monomer coordination and thereby govern subsequent enchainment manners.This unique characteristic also renders the active species highly susceptible to Lewis bases,and may impact the overall selectivity as well as polyme-rization behavior after coordination.Nevertheless,it is still a virgin area in such a field,and the influence of Lewis bases on Nd-based diene polymerizations is still a black box.Based on this consideration,how nitrogen-containing donors(D)impacts the overall behaviors of Nd-mediated Bd polymerizations is disclosed.

考察了外加含氮给电子体对新癸酸钕/三乙基铝/氢化二异丁基铝/乙基倍半铝氯化物催化体系制备顺丁橡胶聚合行为的影响。结果表明,外加1~5份(质量)三辛基胺对聚合物的收率、分子量及其分布等影响不大,但能够明显提高催化剂的顺式-1,4-结构的选择性,聚合物的顺式-1,4-结构摩尔分数由93.66%提高至96.18%。改变外加含氮给电子体种类也能够得到类似效果。