摘要:
A method for preparing a supported catalyst suitable for use in slurry and gas-phase olefin polymerizations is disclosed. An alumoxane-treated silica is combined with a monocyclopentadienyl Group 6 metal complex that comprises a chelating Cp moiety to give the supported catalyst. The method is simple to practice and provides catalysts having high activity. Polyolefins made using the catalysts have high molecular weight that is readily controlled by adding hydrogen.
摘要:
A modified Ziegler-Natta catalyst system, a method for preparing the catalyst system, and a process for polymerizing an olefin in the presence of the catalyst system are disclosed. The catalyst system comprises a titanium or vanadium compound, an aluminum compound, and an indazole. Improved comonomer incorporation and the ability to regulate molecular weight are achieved in the manufacture of polyolefins.
摘要:
A process for polymerizing olefins is disclosed. The process uses an organometallic complex with at least one non-bridged indenoindolyl ligand bonded to M. The substituent on the indole nitrogen contains an atom selected from the group consisting of S, O, P, and N. Polyolefins from the process have unexpectedly high molecular weight compared with polyolefins made using similar supported indenoindolyl complexes.
摘要:
A dual olefin polymerization process is disclosed. The process uses a bridged indenoindolyl ligand-containing Group 4 transition metal complex and an activator. It is carried out in multiple stages or in multiple reactors. The same complex and the same activator are used in all stages or reactors. Different polyolefins are made in different stages or reactors by varying the monomer compositions, hydrogen concentrations, or both. The process of the invention produces polyolefins which have broad molecular weight distributions, composition distributions, or both.
摘要:
A catalyst system useful for polymerizing olefins is disclosed. The catalyst system includes an organometallic complex that incorporates a Group 3 to 10 transition metal and a hydroxyl-depleted calixarene ligand that is chelated to the metal. Molecular modeling studies reveal that organometallic complexes incorporating such calixarene ligands, when combined with an activator such as MAO, should actively polymerize olefins.
摘要:
A catalyst system useful for polymerizing olefins is disclosed. The catalyst system includes an organometallic complex that incorporates a Group 3 to 10 transition metal and an anionic, polycyclic, convex ligand. Molecular modeling results indicate that the complexes, when combined with an activator, should actively polymerize olefins. The convex ligand uniquely stabilizes the active site while simultaneously minimizing steric interference. Calculations predict that complexes based on ligands with a high curvature index will have favorable reactivities with olefin monomers compared with similar complexes that incorporate Cp-like ligands.
摘要:
A process for making ethylene copolymers is disclosed. Ethylene copolymerizes with an α-olefin in the presence of a catalyst system comprising an activator and a silica-supported, bridged indenoindolyl metal complex having "open architecture." The supported complex incorporates comonomers with exceptional efficiency, and the process gives ethylene copolymers having high molecular weights (Mw > 100K) and very low densities ( 3 ). Open architecture catalysts that include bridging through the indolyl nitrogen of the indenoindolyl framework are also described. Additionally, supported and unsupported indeno[1,2-b]indolyl catalysts provide exceptional activities in the preparation of elastomeric polypropylene and ethylene copolymers.
摘要:
Catalyst systems useful for olefin polymerization are disclosed. The catalyst systems include an activator and an organometallic complex. The complex, which incorporates at least one Group 3-10 transition or lanthanide metal, is uniquely prepared from an indenoindolyl dianion or its synthetic equivalent. A diverse array of monomeric, dimeric, polymeric, or zwitterionic complexes are available from the dianion or its equivalent.
摘要:
Catalysts useful for polymerizing olefins are disclosed. The catalysts comprise an activator and a Group 4 transition metal complex which comprises at least one monoanionic R 1 N-XR 2 ligand, where X is O or S, and each of R 1 and R 2 is independently alkyl, aryl, arylalkyl, alkylaryl, or trialkylsilyl. The complexes are readily made from R 1 NH-XR 2 precursors and are often useful as catalyst components without further purification. The catalysts have good activities, incorporate comonomers well, and provide polymers with high molecular weight.
摘要翻译:公开了可用于聚合烯烃的催化剂。 催化剂包含活化剂和第4族过渡金属络合物,其包含至少一种单离子R 1 N-X R 2配体,其中X为O或S,R 1和R 2各自独立地为烷基,芳基,芳基烷基,烷基芳基或三烷基甲硅烷基。 络合物容易由R1NH-XR2前体制成,并且通常用作催化剂组分而不进一步纯化。 催化剂具有良好的活性,很好地加入共聚单体,并提供高分子量的聚合物。
摘要:
A slurry process for polymerizing ethylene is disclosed. The process comprises polymerizing ethylene in the presence of an a-olefin and a catalyst comprising an activator and a supported bridged bis-indeno[2,1-b]indolyl zirconium complex. The process uses a highly active catalyst and provides polyethylene characterized by a high level of long-chain branching.