摘要:
The present invention provides a process for preparing a supported metallocene catalyst system that can be used to catalyze formation of polyolefins having a wide molecular weight range. In accordance with the process of the present invention, a first portion of an inorganic oxide is dried under a first set of conditions, wherein upon treatment with an organoaluminoxide and a metallocene, a first catalyst system is formed usable to produce a polyolefin product having a first molecular weight average distribution. A second portion of an inorganic oxide under a second set of conditions, wherein upon treatment with an organoaluminoxane and a metallocene, a second catalyst system is formed usable to produce polyolefin product having a second molecular weight distribution. An amount of the first portion is mixed with an amount of the second portion to produce a final inorganic oxide support. The final inorganic oxide support is combined with an organoaluminoxane and a metallocene to produce a supported metallocene catalyst system usable to catalyze formation of polyolefins with a broadened molecular weight average distribution. In another aspect, the present invention provides a process for polymerizing polyolefins using the inventive supported metallocene catalyst system. The process comprises preparing the final catalyst as mentioned above and then contacting an olefin with the final metallocene catalyst system under conditions supporting polymerization.
摘要:
Metallocene having two cyclic dienyl groups connected by a single carbon having an aryl substituent and a terminally unsaturated hydrocarbyl substituent, olefin polymerization catalyst systems prepared therefrom, and the use of such catalyst systems are disclosed.
摘要:
Metallocene having two cyclic dienyl groups connected by a single carbon having an aryl substituent and a terminally unsaturated hydrocarbyl substituent, olefin polymerization catalyst systems prepared therefrom, and the use of such catalyst systems are disclosed.
摘要:
Metallocene having two cyclic dienyl groups connected by a single carbon having an aryl substituent and a terminally unsaturated hydrocarbyl substituent, olefin polymerization catalyst systems prepared therefrom, and the use of such catalyst systems are disclosed.
摘要:
Methods are disclosed for preparing a highly active solid metallocene-containing catalyst system and its use in the polymerization of olefins. The catalyst system is prepared by creating a catalyst system solution by combining an aluminoxane with a metallocene having a substituent which has olefinic unsaturation in a suitable liquid to form a liquid catalyst system, conducting prepolymerization of an olefin in the liquid catalyst system, and separating the resulting solid metallocene-containing catalyst system from the reaction mixture. Also polymerization of olefins using the inventive solid catalyst system is disclosed.
摘要:
The present invention provides a new type of supported metallocene catalyst system. In one aspect of the invention, an inorganic oxide support, such as silica, is impregnated with a Group XIII element such as B, Al or GA. The support is then contacted with a liquid catalyst system prepared by combining in a liquid an organo aluminoxane and a metallocene having two cyclopetadienyl-type ligands selected from substituted or unsubstituted cyclopentadienyl, indenyl, benzoindenyl, tetrahdroindenyl, benzofluorenyl, octahydrofluorenyl, and fluorenyl ligands to form a supported metallocene catalyst system. In preferred embodiments the process further includes conducting prepolymerization of at least one olefin in the presence of the supported metallocene catalyst system to produce a prepolymerized metallocene catalyst system. The prepolymerized metallocene catalyst system prepared in this manner yields substantially increased activity for the polymerization of olefins. In another aspect, the present invention also provides a method for polymerization of olefins using the inventive supported metallocene catalyst system.
摘要:
A polymerization process for polymerizing at least one olefin in the presence of a pyridyldiimine metal complex as a catalyst having one of the following structures: The metal M of the complex is a transition metal from Group 4b, 5b or 6b of the Periodic Table such as vanadium. The invention also relates to the use of these metal complexes as olefin polymerization or oligomerization catalysts, optionally in combination with metal alumoxane and similar catalyst activators.
摘要:
A process for producing a new metallocene comprising reacting a first bridged metallocene which has an olefinically unsaturated with about two molar equivalents of an alkali metal alkyl, catalyst systems resulting from the combination of the resulting metallocenes and a cocatalyst, and polymerization processes using such catalyst systems are disclosed.
摘要:
The whiteness and stability after processing of a polyolefin have been found to be improved upon the addition of a combination of at least one high activity phosphite and at least one hydrolytically stable phosphite.