| 摘要 |
A catalyst precursor having the formula: wherein M is a Group IVB metal; each L is a monovalent, bivalent, or trivalent anion; X and Y are each heteroatoms; each Cyclo is a cyclic moiety; each R1 is a group containing 1 to 50 atoms selected from the group consisting of hydrogen and Group IIIA to Group VIIA elements, and two or more adjacent R1 groups may be joined to form a cyclic moiety; each R2 is a group containing 1 to 50 atoms selected from the group consisting of hydrogen and Group IIIA to Group VIIA elements, and two or more adjacent R2 groups may be joined to form a cyclic moiety; W is a bridging group; and each m is independently an integer from 0 to 5. |
