Patent ID: 6727332
Filing Date: 2004-04-27
Classification: C08F,Y10S

Abstract:
A process for producing an isotactic homopolypropylene or copolymers of propylene with enhanced speed of solidification when solidifying from a melt, a difference between a melt temperature and a crystallization temperature not more than 50Â° C., the process comprising polymerizing the isotactic homopolypropylene or copolymers of propylene in the presence of a metallocene catalyst component having the general formula:Râ€³(CpR1R2R3)(Cpâ€²Rnâ€²)MQ2â€ƒâ€ƒ(I) wherein Cp is a substituted cyclopentadienyl ring; Cpâ€² is a substituted or unsubstituted fluorenyl ring; Râ€³ is a structural bridge imparting stereorigidity to the component; R1 is a substituent on the cyclopentadienyl ring which is distal to the bridge, which distal substituent comprises a bulky group of the formula XR*2 in which X is chosen from Group IVA, and one R* is chosen from hydrogen or hydrocarbyl of from 1 to 20 carbon atoms and the other different R* is chosen from a substituted or unsubstituted cycloalkyl where X is a carbon atom in the cycloalkyl ring, R2 is a substituent on the cyclopentadienyl ring which is proximal to the bridge and positioned non-vicinal to the distal substituent and is hydrogen or of the formula YR#3 in which Y is chosen from Group IVA, and each R# is the same or different and chosen from hydrogen or hydrocarbyl of 1 to 7 carbon atoms, R3 is a substituent on the cyclopentadienyl ring which is proximal to the bridge and is a hydrogen atom or is of the formula ZR$3 in which Z is chosen from Group IVA, and each R$ is the same or different and chosen from hydrogen or hydrocarbyl of 1 to 7 carbon atoms, each Râ€²n is the same or different and is hydrogen or hydrocarbyl having 1 to 20 carbon atoms in which 0&lE;n&lE;8; M is a Group IVB transition metal or vanadium and each Q is hydrocarbyl having 1 to 20 carbon atoms or is a halogen.