摘要:
Syndiotactic polymers of vinyl aromatic monomers are prepared by conducting the polymerization in the presence of a catalytic amount of the reaction product of polymethylaluminoxane and a cyclopentadienyl/titanium complex.
摘要:
Syndiotactic polymers of vinyl aromatic monomers are prepared by conducting the polymerization in the presence of a catalytic amount of the reaction product of polymethylaluminoxane and a cyclopentadienyl/titanium complex.
摘要:
A catalyst composition for the polymerization of propylene is provided. The catalyst composition includes one or more Ziegler-Natta procatalyst compositions having one or more transition metal compounds and an internal electron donor, one or more aluminum containing cocatalysts, and a selectivity control agent (SCA). The SCA is a mixture of an activity limiting agent (ALA) and selectivity determining agent (SDA) such as a non-silane composition. The present catalyst composition is silane-free, has high catalyst activity and high stereoselectivity, and is self-extinguishing.
摘要:
A composition comprising a polymerization modifier for the copolymerization of at least one olefin monomer and 1-octene and a polymerization process using the polymerization modifier.
摘要:
A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; a selectivity control agent (SCA) comprising at least one silicon containing compound containing at least one C1-10 alkoxy group bonded to a silicon atom, and one or more activity limiting agent (ALA) compounds comprising one or more aliphatic or cycloaliphatic carboxylic acids; alkyl-, cycloalkyl- or alkyl(poly)(oxyalkyl)-(poly)ester derivatives thereof; or inertly substituted derivatives of the foregoing.
摘要:
A combinatorial method for identifying a catalyst composition for use in the homogeneous addition polymerization of an olefin monomers, said catalyst composition comprising a transition metal compound, a cocatalyst and a polymerization modifier, as well as catalyst compositions and improved olefin polymerization processes resulting therefrom.
摘要:
A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; a selectivity control agent (SCA) comprising at least one silicon containing compound containing at least one C1-10 alkoxy group bonded to a silicon atom, and one or more activity limiting agent (ALA) compounds comprising one or more aliphatic or cycloaliphatic carboxylic acids; alkyl-, cycloalkyl- or alkyl(poly)(oxyalkyl)-(poly)ester derivatives thereof; or inertly substituted derivatives of the foregoing.
摘要:
A catalyst composition for the polymerization of propylene comprising one or more Ziegler-Natta procatalyst compositions comprising one or more transition metal compounds and one or more esters of aromatic dicarboxylic acid internal electron donors; one or more aluminum containing cocatalysts; and a mixture of two or more different selectivity control agents, said SCA mixture comprising from 1 to 99 percent of one or more esters of one or more aromatic monocarboxylic acids or substituted derivatives thereof, and from 99 to 1 percent of one or more alkoxysilane compounds.
摘要:
Disclosed is a process for preparing bridged Group 4 metal complexes containing a neutral diene ligand starting from the corresponding novel, metal diene containing complexes by reaction thereof with the divalent derivative of a bridged bidentate ligand compound. The novel, intermediate metal diene complexes, their formation from tetravalent metal salts and an integrated process combining both process steps are claimed.
摘要:
A process for polymerizing ethylene to produce an ethylene-based polymer including contacting ethylene with a Ziegler-Natta procatalyst, an alkylaluminum cocatalyst and a self limiting agent selected from the group of aliphatic, cycloaliphatic, substituted cycloaliphatic or aromatic esters, anhydrides and amides such that the self limiting agent reduces polymerization rates to no greater than 40% of the polymerization rate in the absence of the self limiting agent at temperatures equal to or greater than 120° C. is provided.