Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component being prepared by the reaction of the following components ?I! and ?II!:?I! a reaction product obtained by reacting the following components (1), (2) and (3) with one another:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.z, X is a halogen atom, and R is a hydrocarbon radical having 1 to 20 carbon atoms; and(3) a titanium compound represented by the general formula Ti(OR).sub.n X.sub.4-n wherein R is a hydrocarbon radical having 1 to 20 carbon atoms, X is a halogen atom, and n is 0.ltoreq.n.ltoreq.

Abstract: Polyolefins exhibiting better particle properties are prepared by polymerizing an olefin or olefins in the presence of a catalyst comprising a solid catalyst component and an organometallic compound, said solid catalyst component being prepared by the reaction of the following components [I] and [II]:[I] a reaction product obtained by reacting the following components (1), (2) and (3) with one another in the presence of a compound represented by the general formula ROH wherein R is a hydrocarbon radical having 1 to 20 carbon atoms or an organic residue containing such an element as oxygen, nitrogen, sulfur, or chlorine:(1) a silicon oxide and/or an aluminum oxide;(2) a reaction product obtained by the reaction of a magnesium halide and compound represented by the general formula Me(OR).sub.n X.sub.z-n wherein Me represents an element of Groups I to IV in the Periodic Table, z represents the valence of the element Me, n is 0<n.ltoreq.

Abstract: A thermoplastic elastomer composition prepared by crosslinking a composition comprising the following components (A), (B) and (C) by using a phenolic curing agent:(A) 30-70 parts by weight of an ethylene/.alpha.-olefin copolymer prepared by copolymerizing ethylene and an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst comprising a solid component and an organoaluminum compound which solid component contains at least magnesium and titanium, said ethylene/.alpha.-olefin copolymer having the following properties (I) to (IV):______________________________________ (I) Melt index 0.01-100 g/10 min (II) Density 0.860-0.910 g/cm.sup.3 (III) Maximum peak temperature as measured according to a not lower than 100.degree. C. differential scanning calorimetry (DSC) (IV) Insolubles in boiling n-hexane not less than 10 wt.

Abstract: A thermoplastic elastomer composition prepared by partially crosslinking a composition comprising the following components (A), (B) and (C):(A) 30-70 parts by weight of an ethylene/.alpha.-olefin copolymer prepared by copolymerizing ethylene and an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst comprising a solid component and an organoaluminum compound which solid component contains at least magnesium and titanium, said ethylene/.alpha.-olefin copolymer having the following properties (I) to (IV):______________________________________ (I) Melt index 0.01-100 g/10 min (II) Density 0.860-0.910 g/cm.sup.3 (III) Maximum peak not lower than 100.degree. C. temperature as measured according to a differential scanning calorimetry (DSC) (IV) Insolubles in boiling not less than 10 wt. % n-hexane ______________________________________(B) 70-30 parts by weight of a propylene polymer; and(C) 70-200 parts by weight, based on 100 parts by weight of the components (A) and (B), of an ethylene/.

Abstract: A thermoplastic elastomer composition prepared by partially crosslinking a composition comprising the following components (A), (B), (C) and (D):(A) 10-40% by weight of an ethylene/.alpha.-olefin copolymer prepared by copolymerizing ethylene and an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst comprising a solid component and an organoaluminum compound which solid component contains at least magnesium and titanium, said ethylene/.alpha.-olefin copolymer having the following properties (I) to (IV):(I) Melt index: 0.01-50 g/10 min(II) Density: 0.860-0.910 g/cm.sup.3(III) Maximum peak temperature as measured according to a differential scanning calorimetry (DSC): not lower than 100.degree. C.(IV) Insolubles in boiling n-hexane: not less than 10 wt. %(B) 15-35% by weight of a propylene polymer;(C) 10-40% by weight of an ethylene/.alpha.

Abstract: A crosslinked resin composition obtained by crosslinking a composition comprising (A) 95-10 wt. % of a propylene polymer and (B) 5-90 wt. % of an ethylene/.alpha.-olefin copolymer having the following properties (I) to (iv) and prepared by copolymerizing ethylene with an .alpha.-olefin having 3 to 12 carbon atoms in the presence of a catalyst, said catalyst comprising a solid component and an organoaluminum compound, said solid component containing at least magnesium and titanium:______________________________________ (i) Melt index 0.01-100 g/10 min (ii) Density 0.860-0.910 g/cm.sup.3 (iii) Maximum peak temperature not lower than 100.degree. C. measured according to a differential scanning calorimetry (DSC) (iv) Insolubles in boiling not less than 10 wt.

Abstract: This invention provides a thermoplastic elastomer composition obtained by blending (A) a hard segment comprising a low-density ethylene-.alpha.-olefin copolymer formed by copolymerizing ethylene with an .alpha.-olefin by the use of a specific catalyst and characterized by specifically defined properties and (B) a soft segment comprising an ethylene-.alpha.-olefin copolymer rubber, or obtained by partial cross-linking of the resulting blend.This elastomer composition has characteristic features such as high flexibility, good fluidity, excellent tensile properties, good thermal resistance and oil resistance and low permanent strain.

Abstract: Provided is a polymer composition having a melt index of 0.01 to 5.0 and a density of 0.870 to 0.940 prepared by blending 30 to 80 parts by weight of an ethylene/.alpha.-olefin copolymer having an intrinsic viscosity determined in decalin at 135.degree. C. of 1.7 to 10 dl/g and a density not higher than 0.945 which copolymer is obtained by copolymerizing ethylene with an .alpha.-olefin of C.sub.3 to C.sub.12, with 70 to 20 parts by weight of a high-pressure process polyethylene having an intrinsic viscosity determined in decalin at 135.degree. C. of not higher than 1.3 dl/g and a density of 0.915 to 0.935.

Abstract: Provided is a polymer composition having a melt index of 0.01 to 5.0 and a density of 0.870 to 0.940 prepared by blending 30 to 80 parts by weight of an ethylene/propylene copolymer having an intrinsic viscosity determined in decalin at 135.degree. C. of 1.7 to 10 dl/g and a density not higher than 0.945 which copolymer is obtained by copolymerizing ethylene with propylene, with 70 to 20 parts by weight of a high-pressure process polyethylene having an intrinsic viscosity determined in decalin at 135.degree. C. of not higher than 0.7 dl/g and a density of 0.915 to 0.935.

Abstract: Provided is a polymer composition having a melt index of 0.01 to 5.0 and a density of 0.880 to 0.940 prepared by blending 10 to 80 parts by weight of an ethylene/.alpha.-olefin copolymer having an intrinsic viscosity determined in decalin at 135.degree. C. of 2.0 to 10 dl/g and a density of less than 0.91 which copolymer is obtained by copolymerizing ethylene with an .alpha.-olefin of C.sub.3 to C.sub.12 in vapor phase condition, with 20 to 90 parts by weight of an ethylene polymer having an intrinsic viscosity determined in decalin at 135.degree. C. of not higher than 1.7 dl/g and a density not less than 0.950.