Abstract: The present invention provides a method for producing homo- and co-polymers of ethylene, or more particularly a method for producing homo- and copolymers of ethylene in the presence of (a) a solid titanium catalyst produced by preparing a magnesium solution by contact-reacting a halogenated magnesium compound with an alcohol; reacting thereto an ester compound having at least one hydroxyl group and a silicon compound having at least one alkoxy group; and adding a mixture of a titanium compound and a silicon compound; (b) organometallic compounds of Group II or III of the Periodic Table; and (c) an alkoxysilane compound and a haloalkne compound. The catalyst for homo- and co-polymerization of ethylene, produced according to the present invention, exhibits a high activity and the polymers produced by the method of the present invention using said catalyst have the advantages of exhibiting a high bulk density and a narrow molecular weight distribution.

Abstract: The present invention provides a prepolymerized olefin polymerization catalyst and olefin polymerization method using the same. More particularly, the present invention provides a prepolymerized catalyst that is encapsulated with macromonomers produced by polymerizing olefin monomers with a vinyl-terminated polysiloxane compound in the presence of a solid titanium catalyst for olefin polymerization having been previously surface treated with silane compounds containing two or more vinyl groups, and a method for producing polyolefin having a high melt strength using the catalyst.

Abstract: The present invention provides a polypropylene resin composition including a polypropylene resin having a melt flow rate of 4-18 g/10 minutes, a flame retardant additive having a low melting point, an antimony oxide, a UV stabilizer, a silane coupling agent, and titanium dioxide as a light-blocking agent. The resin composition of the invention produces products exhibiting excellent flame retarding properties, stability against weather, and maintainability of physical/mechanical properties as shown by maintaining the original flame retarding properties after long periods of outdoor exposure and hydrothermal dipping treatments.

Abstract: A polyolefin resin composition suitable for use in a wheel cover of an automobile including a high-crystalline olefin resin, a polyolefin based elastomer, and an inorganic filler chosen from glass beads coated with a polypropylene grafted with unsaturated carbonic acid or its anhydride and barium sulfate, which is excellent in rigidity, impact strength, heat resistance, mechanical strength, moldability during injection molding, coatability, and appearance without protuberance on the welds and thus suitable for a wheel cover of an automobile.

Abstract: The present invention provides a supported catalyst comprising (A) a polymer (B) a supporter, (C) a transition metal compound, and optionally (D) (a) a compound which can form an ionic complex by the reaction with the transition metal compound or (b) a specific oxygen-containing compound, and (E) an alkylaluminum compound. The supported catalyst according to present invention, which has a high activity, can be used for preparing a styrenic polymer with a high syndiotacticity. The supported catalyst can be used in combination with a cocatalyst, preferably an alkyl aluminoxane.

Abstract: The present invention provides a method for producing homo- and co-polymers of ethylene, or more particularly a method for producing homo- and co-polymers of ethylene in the presence of (a) a solid titanium catalyst produced by preparing a magnesium solution by contact-reacting a halogenated magnesium compound with an alcohol; reacting thereto an ester compound having at least one hydroxyl group and a silicon compound having at least one alkoxy group; and adding a mixture of a titanium compound and a silicon compound; (b) organometallic compounds of Group II or III of the Periodic Table; and (c) a cyclic nitrogen compound. The catalyst for homo- and co-polymerization of ethylene, produced according to the present invention, exhibits high activity, and the polymers produced by the method of the present invention by using said catalyst have the advantages of exhibiting high bulk densities and narrow molecular weight distributions.

Abstract: A method of making an olefin polymerization catalyst is disclosed. The method involves contacting a magnesium halide compound with an alcohol, adding a mineral oil to the product, reacting this product with a hydroxylated ester and an alkoxy silane, then adding a titanium compound and a second silicon compound. The titanium compound is preferably an alkoxy halide, and the second silicon compound is preferably a silicon halide.

Abstract: A method of making an olefin polymerization catalyst is disclosed. The method first combines a magnesium halide with an alcohol, then adds a hydroxylated ester and a silicon alkoxide, followed by a titanium compound and another silicon compound to result in a solid composition. This solid composition is then reacted with an aluminum compound and an alkyl halide, followed by reaction with a second titanium compound which may be the same as or different from the first. The second silicon compound is preferably a silicon halide, and the titanium compounds are preferably halides and alkoxides. The aluminum compounds preferably have chloride and alkyl ligands bonded to them.

Abstract: The present invention relates to a method for the prepolymerization of ?-olefin in the presence of a catalyst system which comprises (a) a magnesium supported solid complex titanium catalyst and (b) an organometallic compound of metal of Group I or III of the Periodic Table, characterized in that an inert solvent having high viscosity with molecular weight of 300 g/mole or more is used as a reaction medium.

Abstract: Disclosed is a preparation method of an exfoliated nitropolymer/silicate nanocomposite by emulsion polymerization of monomers forming the polymer in an aqueous dispersion of non-modified, layered silicate in the presence of a reactive emulsifier having both a radical-polymerizable vinyl group and a functional group with affinity for silicate. In the process of the polymerization, silicate is fully exfoliated and uniformly dispersed in the polymer. Therefore, only a small amount of silicate is sufficient to improve thermal and mechanical properties of the polymer. Further, the method is advantageous in terms of a simple preparation process due to no use of organo-modified silicate, thus achieving an economic benefit.

Abstract: The present invention provides a novel chelated catalyst for olefin polymerization and an olefin polymerization method using the chelated catalyst. The catalyst of the invention is a liquid titanium compound chelated with an imidazole ligand. The method for olefin polymerization of the present invention is performed using the liquid titanium compound as a main catalyst component.

Abstract: Disclosed herein is a polyolefin nanocomposite prepared by polymerizing an olefin monomer in a catalyst system comprising (1) a supported catalyst consisting of a polymer, a silicate clay mineral, and a transition metal compound, and cocatalyst, an alkyl aluminoxane.

Abstract: The supported catalyst according to the present invention comprises a support of organic or inorganic powder with a high-surface area, a polymer coated onto the support and a metallocene catalyst. The polymer (1) contains polar groups; (2) interacts with the surface of the support; and (3) is insoluble in the styrenic monomer or polymerization solvent during polymerization after the catalyst is loaded. The polymer is located between the support and the metallocene catalyst such that the polymer insulates the metallocene layer from the support layer to prevent poisoning of the metallocene catalyst layer by the support layer. The styrenic polymer powder such produced by the present invention has good flow-ability and good morphology demonstrating a great deal of industrial applicability.

Abstract: Disclosed is a preparation method of titanium catalyst for olefin polymerization, the method comprising (1) preparing magnesium compound solution by resolving non-deoxidative magnesium halide and IIIA group atom compound in a solvent mixture of cyclic ether, at least one alcohol, phosphorus compound and organosilane with or without hydrocarbon solvent; (2) reacting said magnesium compound solution with titanium compound, silicon compound, tin compound or mixture thereof to produce a support; and (3) reacting said support with titanium compound and electron donor to produce solid complex titanium catalyst, wherein the particle size and particle size distribution f said catalyst are regulated by controlling solubility of the reactants in said steps (2) and/or (3).

Abstract: The reactor alloy of syndiotactic polystyrene according to the present invention is prepared by polymerizing vinyl aromatic monomer and rubbery elastomer and optionally polyphenylene ether under transition metal catalyst and cocatalyst, which comprises (a) 50-99% by weight of syndiotactic polystyrene, (b) 1-50% by weight of rubbery elastomer, and optionally (c) 0.1-10% by weight of polyphenylene ether. The reactor alloy of the present invention has good dispersibility and high interfacial strength in comparison with a melt blend by polymerizing styrene monomer and rubbery elastomer for impact modifier. And the reactor alloy of the present invention is greatly enhanced in impact resistance in comparison with a melt blend same amount of rubber component as reactor alloy of the present invention without impairing heat resistance and elastic modulus by further comprising polyphenylene ether.

Abstract: The present invention provides a method of preparing a monomer-grafted syndiotactic polystyrene with polarity, which comprises (a) forming swollen syndiotactic polystyrene by mixing with a syndiotactic polystyrene in powder state and a radical initiator in a solvent at the temperature of 40-80° C. using a batch reactor, and (b) grafting a monomer selected from the group consisting of maleic anhydride, maleic imide and derivatives thereof onto the swollen syndiotactic polystyrene.

Abstract: The new metallocene catalysts according to the present invention are prepared by reacting a metallocene compound with a compound having at least two functional groups. The metallocene compound is a transition metal compound which a transition metal is coordinated with a main ligand such as cycloalkanedienyl group and an ancillary ligand. The functional groups of the compound having at least two functional groups are selected from the group consisting of a hydroxy group, a thiol group, a primary amine group, a secondary amine group, etc. The metallocene catalysts according to the present invention have a structure which an ancillary ligand of a metallocene compound is bonded with functional groups. A structure of the metallocene catalysts can be varied according to the metallocene compounds, the compound having at least two functional groups, and the molar ratio of each reactant. The metallocene catalyst is employed with a co-catalyst for styrene and olefin polymerization.