2651 results about "Polymerization catalysts" patented technology

Various catalyst compositions including the contact product of at least one ansa-metallocene compound, at least one organoaluminum compound, and at least one activator-support are disclosed. Processes for forming such compositions and for forming polyolefins with such compositions are also disclosed. Metallocene compounds are also presented.

Copolymers, especially multi-block copolymer containing therein two or more segments or blocks differing in chemical or physical properties, are prepared by polymerizing propylene, 4-methyl-1-pentene, or other C_4-8α-olefin and one or more copolymerizable comonomers, especially ethylene in the presence of a composition comprising the admixture or reaction product resulting from combining: (A) a first metal complex olefin polymerization catalyst, (B) a second metal complex olefin polymerization catalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by catalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

The present invention relates to a catalyst or catalyst system for polymerization and copolymerization of olefine and its synthesis process and the application in catalyzing olefine polymerization. The catalyst is a kind III to XI transition metal compound with multitooth ligand.

A process for carrying the non-metallocene catalyst by composite carrier includes such steps as thermally activating silica gel, reacting on the solution of magnesium chloride in tetrahydrofuran-alcohol solution to obtain composite carrier, reacting on chemical treating agent to obtain modified composite carrier and carrying non-metallocene catalyst by solution method or dipping method. Said catalyst can be used for the homopolymerization or copolymerization of C2-C10 olefin, styrene, or ethylene.

A carrying process for the carried non-metallocene catalyst includes activating the porous carrier, washing, filtering, drying and directly carrying the nno-metallocene catalyst used for olefine polymerization. Said catalyst can be used for the slurry-type or gas-phase homopolymerization or copolymerization of C2-C10 olefin, styrene, or ethylene.

The invention discloses an equivoluminal dipping loading method of non-metallocene olefin polymeric catalyst as well as application of copolymerizing course within two or more different olefins, which comprises the following steps: dissolving non-metallocene olefin polymeric catalyst in the solvent; mixing solution and carrier; stirring wet solid material evenly; drying; obtaining the load-typed non-metallocene olefin polymeric catalyst; making the solvent and carrier satisfy specific relationship.

A method of non- metallocene catalyst loading with high active: the carrier and chemical activating agent reacting with each other to get the modification carrier; dissolving the magnesium compounds into the tetrahydrofuran-alcohol mixing system to form solution, adding the modification carrier into the solution for reaction, filtering, washing, drying and sucting to get the composite carrier; dissolving the non- metallocene catalyst for lkene polymerization into the dissolvent, then reacting with the composite carrier and through process of washing, filtering and drying to get the load non- metallocene catalyst. It can also be: proceeding heating activating treatment before the reaction of carrier with the chemical activating agent; the composite carrier reacting with chemical additive before reacting with catalyst to get the modification composite carrier, the modification composite carrier reacting with catalyst to get the load non- metallocene catalyst. The load catalyst produced in this invention is high active; the load catalyst of high property can be produced with less methylaluoxane; the polyolefine produced with the catalyst prepared in this invention possesses sound granual shape.

A blend of a macrocyclic polyester oligomer and a polymerization catalyst as a one component ready-to-use material with a long shelf life enables production of parts from macrocyclic polyester oligomers without the modification of existing equipment, thereby reducing time and cost of manufacture while expanding the application of macrocyclic polyester oligomers. In this blend material, the macrocyclic polyester oligomer remains intact in solid state at ambient conditions. Upon melting, the blend material initially forms low viscosity fluid, and then rapidly polymerizes to form high molecular weight polyesters which subsequently solidify to form crystalline polymers. In the case of certain macrocyclic polyester oligomers, for example, poly(1,4-butylene terephthalate), demolding can take place at the polymerization temperature, e.g., at about 180° C. to 200° C., because the resulting polyester polymer solidifies fairly rapidly at that temperature without cooling. In one aspect, the invention generally features a blend material that includes a macrocyclic polyester oligomer, a polymerization catalyst, and optionally, a filler. In another aspect, the invention generally features a process for preparing a blend material. In yet another aspect, the invention features processes such as rotational molding, resin film infusion, pultrusion, resin transfer molding, filament winding, making and using powder-coated or hot melt prepreg, compression molding, and roll wrapping, which use the blend material.

The invention relates to spherical carriers for an olefin polymerization catalyst and a preparation method. Each spherical carrier comprises reaction products of the following components: (1) magnesium halide which is shown as the general formula MgX2, (2) alcohol compounds which are shown as the general formula ROH, and (3) ethylene oxide compounds which are shown as the general formula (I), wherein in the general formula (I), R2 and R3 are alkyls with a C1-C5 straight chain or branched chain; and hydrogen on the alkyls can be randomly substituted by a halogen atom. The spherical carriers have good particle shapes, adjustable particle sizes and narrow particle size distribution, and the preparation method is simple.

A process for polymerizing propylene is provided. The process comprises contacting propylene and optionally one or more monomers with a catalyst system comprising a bis-indenyl Group 4 metallocene compound supported on silica, the silica treated with one or more organoaluminum compounds and one or more heterocyclic compounds, under slurry conditions in the presence of hydrogen at a temperature of about 50° C. to about 160° C. and a pressure of from about 3 MPa to about 5 MPa to provide a catalyst activity of greater than 30,000 pounds of product per pound of catalyst; and then recovering isotactic polypropylene having a melt flow rate of 20 dg/min or less as measured according to ASTM D-1238 at 230° C. and 2.16 kg.

The invention discloses an alpha-nickel diimine compound olefin polymerization catalyst and a preparation method thereof, and a method for preparing branched polyethylene. Structural formulas of the alpha-nickel diimine compound olefin polymerization catalyst are shown as a formula (I) and a formula (II), and the preparation method of the alpha-nickel diimine compound olefin polymerization catalyst is simple and low in cost, and can catalyze ethylene polymerization with high activity at a temperature of more than or equal to 80 DEG C to obtain high molecular weight polyethylene. The polyethylene prepared by catalyzing of the alpha-nickel diimine compound olefin polymerization catalyst has high molecular weight, and can prepare molecular weight which reaches more than 10<2>*kg/mol in the temperature range of between 0 and 80 DEG C.

This invention relates to catalyst compositions, methods, and polymers encompassing a Group 4 metallocene with bridging η⁵-cyclopentadienyl-type ligands, in combination with a cocatalyst and an activator-support. The compositions and methods disclosed herein provide ethylene polymers with low levels of long chain branching.

The present invention provides polymerization catalyst compounds, catalyst systems including these catalyst compounds, and to their use in the polymerization of ethylene and at least one comonomer. In particular, the invention provides a catalyst system comprising a poor comonomer incorporating catalyst compound and a good comonomer incorporating catalyst compound. Preferably, the low comonomer incorporating catalyst compound is a metallocene containing at least one substituted or unsubstituted fused ring cyclopentadienyl based ligand which is substantially directed to the front of the molecule, contains a long bridging group, or which contains a methyl substitution pattern which correlates to poor comonomer incorporation. The invention also provides methods of selecting the poor comonomer incorporating metallocene to pair with the good comonomer incorporating metallocene to produce polymers that are easy to process into a variety of articles, especially polyethylene based film, having enhanced properties.

A process for the production of a propylene based polymer, the process comprising the following steps: (a) a first polymerization stage comprising homopolymerizing propylene or copolymerizing propylene and at least one alpha-olefin in the presence of an alpha-olefin polymerization catalyst whereby to produce a polypropylene component; (b) a second polymerization stage comprising copolymerizing ethylene and at least one alpha-olefin in the presence of an alpha-olefin polymerization catalyst whereby to produce an ethylene/alpha-olefin copolymer component; and (c) blending the polymer components produced in steps (a) and (b) whereby to produce a polymer blend, wherein the first and second polymerization stages are effected in separate polymerization reactors connected in parallel. Also provided are polymer compositions comprising: (i) 30 to 97% by weight, based on the total weight of the polymer composition, of a propylene based polymer; and (ii) 3 to 70% by weight, preferably 5 to 20% by weight, based on the total weight of the polymer composition, of an ethylene copolymer plastomer (e.g., an ethylene-propylene plastomer) containing at least 60% by weight ethylene.

A method for forming an electrolytic capacitor is disclosed. The method includes forming a conductive polymer coating by polymerizing a monomer in the presence of less than a stoichiometric amount of an oxidative polymerization catalyst. The present inventor has found that the use of less than the stoichiometric amount of the oxidative polymerization catalyst per mole of monomer can slow the polymerization of the monomer, creating oligomers that are shorter in length than if fully polymerized into a polymer. Without wishing to be bound by theory, it is believed that these shorter oligomers provide better penetration into the porous anode. Thus, the resulting conductive polymer layer can be more intimately positioned with respect to the anode. As a result, the formed capacitor can exhibit better performance.