Abstract: An olefin polymerization catalyst formed from (A) a solid titanium catalyst component containing magnesium, titanium and halogen as essential ingredients, (B) an organoaluminum compound, and (C) an organosilicon compound containing a cyclopentyl group, a cyclopentenyl group, a cyclopentadienyl group or a derivative derived from any of these groups.A polymerization process which comprises polymerizing or copolymerizing olefins in the presence of the olefin polymerization catalyst to form a homopolyolefin having high stereoregularity or a copolyolefin having a narrow composition distribution.

Abstract: Disclosed is a thermoplastic resin composition comprising(A) an aromatic polyamide comprisingdicarboxylic acid units comprising 50-100 mol % of units derived from terephthalic acid, and 0-50 mol % of units derived from an aromatic dicarboxylic acid other than terephthalic acid and/or an aliphatic-dicarboxylic acid having 4-20 carbon atoms, anddiamine units derived from an aliphatic diamine and/or an alicyclic diamine,said aromatic polyamide having an intrinsic viscosity of 0.5-3.0 dl/g as measured in conc. sulfuric acid at 30.degree. C. and a melting point of higher than 300.degree. C.,(B) a graft modified .alpha.-olefin polymer, and/or a graft modified aromatic vinyl hydrocarbon/conjugated diene copolymer or hydrogenated product thereof, and(C) an aliphatic polyamide,wherein said thermoplastic resin composition comprises 10-80 parts by weight of the graft modified .alpha.

Abstract: An injection-molded article of a thermoplastic resin having a base body defining an outer shape of the injection-molded article, a thick-wall portion rising from the base body, and a foot portion formed on the base body and at a foot of the thick-wall portion, the foot portion rising from the base portion, having a thickness which gradually increases toward the thick-wall portion, and having a (maximum thickness of the foot portion)/(width extending from the thick-wall portion to an end of the foot portion) ratio of 1/40 to 1/2, at least the thick-wall portion having a hollow portion.

Abstract: In accordance with the present invention, there are provided an olefin polymerization catalyst formed from:[A] a compound of a transition metal belonging to Group IV B of the periodic table,[B] an aluminoxane, and[C] water,an olefin polymerization catalyst formed from [D] an organoaluminum compound in addition to the above-mentioned [A], [B] and [D] components, and processes for the polymerization of olefins using the above-mentioned olefin polymerization catalysts, respectively.

Abstract: A random copolymer of propylene with from 1 to 10 mol % of a C.sub.4 to C.sub.20 .alpha.-olefin and an intrinsic viscosity of 0.5 to 6 dl/g is also characterized by a melting point (Tm) measured by a differential scanning calorimeter falling within the range of 90<Tm<155-3.5(100-P) (wherein P is the propylene content (mol %) present in the copolymer), a molecular weight distribution (Mw/Mn) of less than 3.5, and a boiling trichloroethylene-insoluble content of less than 5% by weight. Terpolymers of propylene-ethylene-C.sub.4 -C.sub.20 .alpha.-olefin wherein Tm falls within the range of 70<Tm<155 -5.5(100-P) are also described. The propylene random copolymer is prepared by polymerizing propylene, .alpha.-olefin, and optionally, ethylene in the presence of a catalyst system which includes an hafnium compound having a multidentate ligand and two or more cycloalkadienyl groups linked together via an alkylene linkage, and an organoaluminum oxy-compound.

Abstract: In accordance with the present invention, there are provided an olefin polymerization catalyst formed from:[A] a compound of a transition metal belonging to Group IV B of the periodic table,[B] an aluminoxane, and[C] water,an olefin polymerization catalyst formed from [D] an organoaluminum compound in addition to the above-mentioned [A], [B] and [D] components, and processes for the polymerization of olefins using the above-mentioned olefin polymerization catalysts, respectively.

Abstract: A method for producing a handle-shaped molded article (1) having a thick grip portion (2) and at least one thick fitting portion (3) by injection molding using an injection molding apparatus (10) equipped with a mold having a cavity (60), a resin gate (46) provided in a portion (62) where the fitting portion is to be formed and a gas inlet (48) provided in a portion (64) where the grip portion is to be formed. A hollow structure (4) is formed in the grip portion (2) and a solid structure is formed in the fitting portion (3) by injecting a molten resin into the cavity (60) through the resin gate (46), thereby filling molten resin in a fitting portion-forming cavity zone formed of that portion (62) of the mold where the resin gate is provided and the fitting portion is to be formed and further filling molten resin in part of the rest of the cavity.

Abstract: The resin composition of the invention comprises as resin components specific aromatic polyamide (A), a specific graft-modified polymer (B), an aliphatic polyamide (C), and plural antioxidants comprising a hindered phenol type antioxidant (D) having a molecular weight of not less than 500 and a TGA 10% weight loss temperature of not lower than 300.degree. C. and a sulfur type antioxidant (E) having a molecular weight of not less than 600 and a TGA 10% weight loss temperature of not lower than 280.degree. C. The connector of the invention has housing formed from the above-mentioned resin composition. The resin composition of the invention shows excellent heat resistance. The connector of the invention is lightweight and is excellent in heat resistance, water resistance and chemical resistance.

Abstract: Proposed herein is a process for preparing thermoplastic elastomers, which comprises dynamically heat treating polymer particles together with a crosslinking agent, each of the polymer particles being composed of a portion comprising a crystalline olefin polymer and portions comprising an amorphous olefin polymer, the polymer particles having an average particle diameter of at least 10 .mu.m and an apparent bulk density of at least 0.2 g/ml.

Abstract: A process for producing polypropylene, which comprises preliminarily polymerizing 3-methylbutene-1 in the presence of a catalyst system formed from[A] a solid titanium catalyst component containing magnesium, titanium, halogen and polycarboxylic acid esters as essential components,[B] an organoaluminum compound, and[C] an organosilicon compound represented by the general formula R.sub.n Si(OR').sub.4-n wherein R and R' represent a hydrocarbon group, and 0<n<4, the amount of the 3-methylbutene-1 preliminarily polymerized being 0.1 to 100 g per gram of the solid titanium catalyst, and thereafter, polymerizing propylene or copolymerizing propylene and an alpha-olefin in the presence of the catalyst used in the preliminary polymerization to such an extent that the amount of the monomer or monomers polymerized is from 1,000 to 100,000 times the amount of the 3-methylbutene-1 preliminarily polymerized.

Abstract: A catalyst component (X") obtained by treating an olefin polymerization catalyst (X) formed from (A) a solid titanium catalyst component comprising magnesium, titanium, halogen and an electron donor as essential ingredients, (B) an organoaluminum compound catalyst component, and as required, (C) an electron donor with an alpha-olefin by preliminarily polymerizing the alpha-olefin in an amount of 0.1 to 500 g per gram of the solid titanium catalyst component (A) in the presence of said catalyst (X), and contacting the treated catalyst (X') with at least 0.1 mole, per gram-atom of titanium in the treated catalyst (X'), of oxygen. A process for producing the olefin polymerization catalyst component. A catalyst (Y) for olefin polymerization formed from [I] the above catalyst component (X"), [II] an organoaluminum compound catalyst component and as required [III] an electron donor. Also provided is a process for polymerizing olefins in the presence of the olefin polymerization catalyst (Y).

Abstract: In accordance with the present invention, there are provided ethylene copolymers composed of structural units (a) derived from ethylene and structural units (b) derived from .alpha.-olefin of 3.about.20 carbon atoms, said ethylene copolymers having[A] a density of 0.85.about.0.92 g/cm.sup.3,[B] an intrinsic viscosity [.eta.] as measured in decalin at 135.degree. C. of 0.1.about.10 dl/g,[C] a ratio (Mw/Mn) of a weight average molecular weight (Mw) to a number average molecular weight (Mn) as measured by GPC of 1.2.about.4, and[D] a ratio (MFR.sub.10 /MFR.sub.2) of MFR.sub.10 under a load of 10 kg to MFR.sub.2 under a load of 2.16 kg at 190.degree. C. of 8.about.50, and being narrow in molecular weight distribution and excellent in flowability.

Abstract: An olefin is polymerized or copolymerized under the presence of an olefin-polymerizing catalyst prepared from (A) a transition-metal compound or (A') a transition-metal compound loaded on a fine-particle carrier, said transition metal being selected from group IVB in the periodic table; (B) an aluminoxane; and (C) an organoaluminum compound represented by the general formula [I] or [II]:R.sup.1.sub.m Al(OR.sup.2).sub.3-m [I]R.sup.3.sub.n Al(OSiR.sup.4.sub.3).sub.3-n [II]wherein R.sup.1, R.sup.2, and R.sup.3 are selected from hydrocarbon radicals, R.sup.4 is selected from the group consisting of hydrocarbon, alkoxy, and aryloxy radicals, and m and n are positive numbers of 0<m<3 and 0<n<3. This catalyst has a significantly high polymerization activity, and the thus produced olefin polymer or copolymer has a narrow composition distribution, a high bulk density, and uniform grain size with little powdery product.

Abstract: The present invention relates to a process for polymerizing olefins.In the process of the present invention, olefins are polymerized using a catalyst composed of a compound of a transition metal (e.g. zirconium) of Group IVB of the periodic table, an aluminoxane produced from trimethylaluminum, and an aluminoxane wherein at least one hydrocarbon group other than n-alkyl groups is bonded to an aluminum atom. The present process can polymerize olefins with excellent polymerization activity and can produce an olefin polymer having a relatively large molecular weight even when the use amount of the aluminoxane produced from trimethylaluminum (which is expensive) is small.

Abstract: In accordance with the present invention, there are provided carrier-supported titanium catalyst components containing magnesium, aluminum, halogen and titanium as essential ingredients, which are obtained by a reaction of[I] a magnesium containing support obtained by previously bringing a support into contact with an organometallic compound of a metal of the Group II to IIIA of the periodic table having at least one hydrocarbon group attached directly to the metal atom or with a halogen containing compound, followed by contact with a magnesium compound in the liquid state having no reducing ability,[II] a reducing organometallic compound, and[III] a titanium compound in the liquid state, and processes for preparing the same and, at the same time, catalysts containing the above-mentioned catalyst components for use in preparing ethylene polymer and processes for preparing ethylene polymer using the catalyst for use in preparing ethylene polymer.

Abstract: In accordance with the present invention, there are provided olefin polymerization catalyst components comprising an organoaluminum oxy-compound having less than 10% in terms of Al atom of Al component dissolving in benzene kept at 60.degree. C., and olefin polymerization catalyst containing said olefin polymerization catalyst components. The olefin polymerization catalysts have excellent polymerization activities, and are capable of giving olefin (co)polymers having a narrow molecular weight distribution and a narrow composition distribution.

Abstract: A process for producing polypropylene, which comprises preliminarily polymerizing 3-methylbuten3-1 in the presence of a catalyst system formed from[A] a solid titanium catalyst component containing magnesium, titanium, halogen and polycarboxylic acid esters as essential components,[B] an organoaluminum compound, and[C] an organosilicon compound represented by the general formula R.sub.n Si(OR').sub.4-n wherein R and R' represent a hydrocarbon group, and 0<n<4, the amount of the 3-methylbutene-1 preliminarily polymerized being 0.1 to 100 g per gram of the solid titanium catalyst, and thereafter, polymerizing propylene or copolymerizing propylene and an alpha-olefin in the presence of the catalyst used in the preliminary polymerization to such an extent that the amount of the monomer or monomers polymerized is from 1,000 to 100,000 times the amount of the 3-methylbutene-1 preliminarily polymerized.

Abstract: In accordance with the present invention, there are provided carrier-supported titanium catalyst components containing magnesium, aluminum, halogen and titanium as essential ingredients, which are obtained by a reaction of[I] a magnesium containing support obtained by previously bringing a support into contact with an organometallic compound of a metal of the Group II to IIIA of the periodic table having at least one hydrocarbon group attached directly to the metal atom or with a halogen containing compound, followed by contact with a magnesium compound in the liquid state having no reducing ability,[II] a reducing organometallic compound, and[III] a titanium compound in the liquid state, and processes for preparing the same and, at the same time, catalysts containing the above-mentioned catalyst components for use in preparing ethylene polymer and processes for preparing ethylene polymer using the catalyst for use in preparing ethylene polymer.

Abstract: A solid catalyst for polymerizing an olefin is prepared from an organometallic compound, a fine-particle carrier, an aluminoxane, a compound of group IVB transition metal in periodic table, and an olefin polymer produced in a preliminary polymerization. The catalyst has a high polymerization activity and is capable of producing an olefin polymer having a narrow molecular- weight distribution. When the catalyst is used for producing an olefin copolymer, the resulting copolymer has both narrow molecular-weight distribution and composition distribution.

Abstract: An olefin is polymerized or copolymerized under the presence of an olefin-polymerizing catalyst prepared from (A) a transition-metal compound or (A') a transition-metal compound loaded on a fine-particle carrier, said transition metal being selected from group IVB in the periodic table; (B) an aluminoxane; and (C) an organoaluminum compound represented by the general formula [I] or [II]:R.sup.1.sub.m Al(OR.sup.2).sub.3-m [I]R.sup.3.sub.n Al(OSiR.sup.4.sub.3).sub.3-n [II]wherein R.sup.1, R.sup.2, and R.sup.3 are selected from hydrocarbon radicals, R.sup.4 is selected from the group consisting of hydrocarbon, alkoxy, and aryloxy radicals, and m and n are positive numbers of 0<m<3 and 0<n<3. This catalyst has a significantly high polymerization activity, and the thus produced olefin polymer or copolymer has a narrow composition distribution, a high bulk density, and uniform grain size with little powdery product.