This invention relates to metallocene compositions and their use in the preparation
of catalyst systems for olefin polymerization, particularly propylene polymerization.
The metallocene compositions are generally those of the bridged bis(2-R3-4-phenylindenyl)metallocene
type wherein the bridge is represented by the formula:
##STR1##
wherein: R17 to R24 are identical or different and
are one of a hydrogen atom, a C1-C10 alkyl group, a C1-C10
alkoxy group, a C6-C10 aryl group, a C6-C10
aryloxy group, a C2-C10 alkenyl group, a C7-C40
arylalkyl group, a C7-C40 alkylaryl group, a C8-C40
arylalkenyl group, or a halogen atom, or a conjugated diene which is optionally
substituted with one or more hydrocarbyl, tri(hydrocarbyl)silyl groups or hydrocarbyl,
tri(hydrocarbyl)silylhydrocarbyl groups, said diene having up to 30 atoms not counting
hydrogen; or two or more adjacent radicals R17 to R24, including
R20 and R21, together with the atoms connecting them form
one or more rings; preferably, R17 to R24 are hydrogen, and
M2 is carbon, silicon, germanium or tin, preferably silicon.
