| 摘要 |
A catalyst system contains (a) a cocatalyst and (b) a bimetallic transition metal compound of formula (I) in which M<1> is a transition metal of group IIIb-VIb; radicals Y are the same or different and stand for H, R, OH, NR2 or Y is a substituted or unsubstituted butadiene unit; k is an integer; radicals A are the same or different and represent a substituted or unsubstituted cyclopentadienyl ligand of which at least one must be substituted; radicals B are the same or different and represent a bridge; radicals D are the same or different and represent X-R<5>m; X is bonded to B by covalence and to M<2> by co-ordination; X is an element of groups Va or VI of the periodic table of elements; radicals R<5> are the same or different and represent H, X, or R, or two radicals R<5> form one or more rings with their bonding atoms; m equals 1 or 2; M<2> is a metal of groups VIb-Xb of the periodic table of elements; radicals W are the same or different and represent H, R, X, OR or NR2, or W represents a substituted or unsubstituted butadiene unit; j is an integer equal to 0, 1, 2, 3, 4, 5 or 6 which corresponds to the valence of the transition metal atom M<2>; L is a neutral donor ligand; and i is an integer from 0 to 10. |
