申请人:California Institute of Technology
公开号:US05708101A1
公开(公告)日:1998-01-13
A metallocene catalyst system for the polymerization of .alpha.-olefins to yield stereospecific polymers including syndiotactic, and isotactic polymers. The catalyst system includes a metal and a ligand of the formula ##STR1## wherein: R.sup.1, R.sup.2, and R.sup.3 are independently selected from the group consisting of hydrogen, C.sub.1 to C.sub.10 alkyl, 5 to 7 membered cycloalkyl, which in turn may have from 1 to 3 C.sub.1 to C.sub.10 alkyls as a substituent, C.sub.6 to C.sub.15 aryl or arylalkyl in which two adjacent radicals may together stand for cyclic groups having 4 to 15 carbon atoms which in turn may be substituted, or Si(R.sup.8).sub.3 where R.sup.8 is selected from the group consisting of C.sub.1 to C.sub.10 alkyl, C.sub.6 to C.sub.15 aryl or C.sub.3 to C.sub.10 cycloalkyl; R.sup.4 and R.sup.6 are substituents both having van der Waals radii larger than the van der Waals radii of groups R.sup.1 and R.sup.3 ; R.sup.5 is a substituent having a van der Waals radius less than about the van der Waals radius of a methyl group; E.sup.1, E.sup.2 are independently selected from the group consisting of Si(R.sup.9).sub.2, Si(R.sup.9).sub.2 --Si(R.sup.9).sub.2, Ge(R.sup.9).sub.2, Sn(R.sup.9).sub.2, C(R.sup.9).sub.2, C(R.sup.9).sub.2 --C(R.sup.9).sub.2, where R.sup.9 is C.sub.1 to C.sub.10 alkyl, C.sub.6 to C.sub.15 aryl or C.sub.3 to C.sub.10 cycloalkyl; and the ligand may have C.sub.S or C.sub.1 -symmetry. Preferred metals are selected from the group consisting of group III, group IV, group V or lanthanide group elements. The catalysts are used to prepare stereoregular polymers including polypropylene from .alpha.-olefin monomers.
一种金属茂配位催化剂体系,用于聚合α-烯烃以产生立体特异性聚合物,包括顺反型和同反型聚合物。催化剂体系包括金属和配体,其化学式为##STR1##其中:R1、R2和R3独立地选择自氢、C1到C10烷基、5到7成员环烷基,其又可以具有1到3个C1到C10烷基作为取代基,C6到C15芳基或芳基烷基,其中两个相邻基团可以代表具有4到15个碳原子的环状基团,其又可以被取代,或Si(R8)3,其中R8选择自C1到C10烷基,C6到C15芳基或C3到C10环烷基;R4和R6是取代基,其范德华半径均大于基团R1和R3的范德华半径;R5是具有范德华半径小于甲基基团的范德华半径的取代基;E1、E2独立地选择自Si(R9)2,Si(R9)2-Si(R9)2,Ge(R9)2,Sn(R9)2,C(R9)2,C(R9)2-C(R9)2,其中R9选择自C1到C10烷基,C6到C15芳基或C3到C10环烷基;并且配体可以具有C.S或C1对称性。优选金属选择自III、IV、V族或镧系元素。该催化剂用于从α-烯烃单体制备立体规则聚合物,包括聚丙烯。