Abstract:
Zirconocene compounds with two indenyl ligands linked in the 2 position by means of a two-carbon-atoms divalent bridging group can be suitably used as components of catalysts for the polymerization of olefins. Particularly it is possible to prepare, with high yields, ethylene (co)polymers having low molecular weights and narrow molecular weight distributions, without the need of using considerable amounts of molecular weight regulators, such as hydrogen.
Abstract:
The present invention provides a method of making a catalyst for improving the performance of liquid hydrocarbon fuel. The treating agent for improving the performance of liquid hydrocarbon fuel is made by preparing a resin or a rubber composition having 100 parts by weight of a resin or a rubber component, 15 to 60 parts by weight of a carbon source having a particle size of not more than 0.5 mm and containing anthracite in amount not less than 62.5%, to 85 parts by weight of a silicon dioxide source having a particle size of not more 0,5 mm and containing quartz sand in an amount not less than 8-% and 5 to 15 parts by weight of glass fiber having an average fiber length of 6 to 12 &mgr;m, press molding the composition to obtain a molded article, and aging the molded article.
Abstract:
The present invention relates to a catalyst for polymerization or copolymerization of an olefin. The catalyst is produced by first reacting a mixture of a magnesium compound and an aluminum compound with an ester compound which has at least one hydroxy group and a silane compound which has at least one alkoxy group, and next reacting with a titanium compound. The catalyst may be used in the polymerization or copolymerization of ethylene and propylene. The catalyst is believed to have the following formula: a{Mg(OR1)jX12−j}b{Al(OR2)kX23−k}c{(ExED)1Ti(OR3)m(ED)(n4)−m−n} where, R1˜R3=hydrocarbon group, X1˜X2=halogen atoms, ExED=silane compounds comprising an alkoxy group, ED=an ester compound having at least one hydroxy group and a hydrogen of the hydroxy group is removed, and 0
Abstract:
A catalyst component, adapted for use in the polymerization and copolymerization of ethylene, is formed by reaction of an organomagnesium compound with a metal oxide support to form a supported organomagnesium composition, reaction of the supported organomagnesium composition and a tetraalkyl silicate, contact of the resulting product with a chlorinating reagent, and treatment of the product from the previous step with liquid titanium halide.
Abstract:
Catalyst compositions comprising 1) one or more bimetallic Group 3-6 or Lanthanide metal complexes corresponding to the formula: wherein: M and M′ are independently Group 3, 4, 5, 6, or Lanthanide metals; L is a divalent group (or trivalent group if bound to Q) having up to 50 nonhydrogen atoms and containing an aromatic &pgr;-system through which the group is bound to M, said L also being bound to Z; L′ is a monovalent group or a divalent group (if bound to L″ or Q), or a trivalent group (if bound to both L″ and Q) having up to 50 nonhydrogen atoms and containing an aromatic &pgr;-system through which the group is bound to M′; L″ is a monovalent group or a divalent group (if bound to L′ or Q), or a trivalent group (if bound to both L′ and Q) having up to 50 nonhydrogen atoms and containing an aromatic &pgr;-system through which the group is bound to M′, or L″ is a moiety comprising boron or a member of Group 14 of the Periodic Table of the Elements, and optionally also comprising nitrogen, phosphorus, sulfur or oxygen, said L″ having up to 20 non-hydrogen atoms; Z is a moiety comprising boron or a member of Group 14 of the Periodic Table of the Elements, and also comprising nitrogen, phosphorus, sulfur or oxygen, said Z having up to 20 non-hydrogen atoms; X, X′ and X″ are as defined in the specification; Q is a divalent anionic ligand group bound at one terminus to either Z or L and bound at the remaining terminus to either L′ or L″, said Q having up to 20 nonhydrogen atoms; and x, x′, and x″ are independently integers from 0 to 3; and 2) one or more activating cocatalysts; wherein activating cocatalyst component 2) causes both metal centers, M and M′, of the one or more bimetallic metal complexes 1) to be catalytically active for the polymerization of addition polymerizable monomers.
Abstract:
Supported heterometallocene catalysts wherein the support is a particulate polymeric material are provided. The catalysts have a transition metal complex containing at least one anionic, polymerization stable heteroatomic ligand associated with the transition metal and a boron activator compound deposited on the support. Polymeric supports used for the heterometallocene catalysts of the invention are homopolymers of ethylene and copolymers of ethylene and C3-8 &agr;-olefins.
Abstract:
A polymerization catalyst obtained by contacting metallic magnesium with an aromatic halide, RX, under conditions effective to obtain a first reaction product and solid residual products is disclosed. The first reaction product is then separated from the solid residual products. A silane compound containing an alkoxy or aryloxy group is added to the first reaction product between −20° C. to 20° C. to obtain a precipitate which is purified to obtain a second reaction product. Subsequently, the second reaction product is contacted with a halogenized titanium compound, such as, titanium tetrachloride, to obtain a further reaction product. The polymerization catalyst is obtained by purifying the further reaction product. In the aromatic halide, R represents an aromatic group containing from 6 to 20 carbon atoms and X represents a halide. An electron dopor such as dibutyl phthalate may also be present during the titanium addition.
Abstract:
The invention is a catalyst system including a monocyclopentadienyl titanium compound, where the monocyclopentadienyl group is bonded to a silylene-imido moiety which is further bonded to the titanium atom, and an alumoxane component which is highly productive for polymerizing ethylene and &agr;-olefins to produce a high molecular weight ethylene-&agr;-olefin copolymer having a high content of &agr;-olefin.
Abstract:
A heterogeneous catalyst for olefin polymerization is prepared by spray drying a mixture of a metallocene catalyst, a cocatalyst and a hydrotalcite. It Preferred hydrotalcites are magnesium-aluminum hydroxy carbonates. The catalysts are very active for ethylene polymerization. The hydrotalcite used in this invention are generally defined by the formula: (Mg1−x Alx(OH)2)n+An−x/n·m H2O wherein X is from 0 to 0.5, m is from 0 to 20 and An− is an anion having a charge of n. Preferred hydrotalcites are those in which the anion A is a carbonate and which have been dried of adsorbed water.
Abstract:
Transition metal imine complexes can be prepared by reacting the imine precursors, a carbonyl compound and a primary amine, in the presence of a selected transition metal compound. The complexes may be used as catalysts for olefin polymerization.