Abstract: Disclosed is a molecularly oriented molded body of an ultra-high-molecular-weight ethylene/.alpha.-olefin copolymer having an intrinsic viscosity (.eta.) of at least 5 dl/g and such a content of an .alpha.-olefin having at least 3 carbon atoms that the number of molecules of the .alpha.-olefin is 0.1 to 15 on the average per 1000 carbon atoms, wherein the molded body shows at least two crystal fusion endothermic peaks when the measurement is conducted in the restraint state by using a differential scanning calorimeter, the molded body has at least one crystal fusion endothermic peak (Tp) at a temperature higher by at least 20.degree. C. than the inherent crystal fusion temperature (Tm) of the ultra-high-molecular-weight ethylene/.alpha.-olefin copolymer determined as the main fusion endothermic peak at the time of the second elevation of the temperature, and the quantity of heat based on said crystal fusion endothermic peak (Tp) is at least 15% based on the total fusion heat quantity.

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 a polymer or copolymer of an olefin which comprises polymerizing or copolymerizing at least one olefin with or without a diolefin in the presence of a catalyst composed of (A) a magnesium-containing solid titanium catalyst component containing magnesium, titanium, a halogen and an electron donor as essential ingredients and (B) an organoaluminum compound catalyst component; characterized in that(1) said catalyst further comprises (C) an organic silicon compound catalyst component having an Si--O--C or Si--N--C bond, and(2) said electron donor in the catalyst component (A) is a cyclic mono- or poly-ester such as diethyl furane-3,4-dicarboxylate, di-n-butyl 3,4-dihydro-2H-pyrane-5,6-dicarboxylate, di-isobutyl pyrrole-2,3-dicarboxylic, di-n-butyl thiophene-2,3-dicarboxylate, n-octyl pyrrolidine-2,3-dicarboxylate, and so on.

Abstract: A process for producing a propylene polymer having good flowability with an MFR of at least 10 g/10 minutes comprises a first polymerization stage consisting of at least two steps and a subsequent second polymerization stage. It is important to control the intrinsic viscositites of a crystalline propylene polymer obtained from the first step of the first polymerization stage and a crystalline propylene polymer obtained from the final step of the first polymerization stage.

Abstract: An olefin polymerization catalyst component subjected to successive preliminary polymerization treatment using each of a straight chain alpha-olefin having 2 to 5 carbon atoms and 3-methyl-1-butene; an olefin polymerization catalyst using the olefin polymerization catalyst component; a process for polymerizing olefin(s) which comprises polymerizing or copolymerizing olefin(s) in the presence of the olefin polymerization catalyst; and a film and an injection-molded article of polypropylene which is prepared by the process are also provided.

Abstract: A cyclo-olefinic random copolymer composed of an alpha-olefin component having 3 to 20 carbon atoms and a cyclo-olefin component,(i) said copolymer containing 5 to 99 mole % of recurring units derived from said alpha-olefin component having 3 to 20 carbon atoms and 1 to 95 mole % of recurring units derived from said cyclo-olefin component, and(ii) said copolymer having an intrinsic viscosity [.eta.], measured in decalin at 135.degree. C., of from 0.01 to 10 dl/g; and an olefinic random copolymer composed of (A) an olefin component having 3 to 20 carbon atoms and (B) a cyclic polyene component and as required, (C) a cyclo-olefin component,(i) said copolymer containing 5 to 99 mole % of recurring units derived from said alpha-olefin component (A) having 3 to 20 carbon atoms and 1 to 95 mole % of recurring units derived from said cyclic polyene component (B) and 0 to 90 mole % of recurring units derived from said cyclo-olefin component (C), and(ii) said copolymer having an intrinsic viscosity [.eta.

Abstract: A cyclo-olefinic random copolymer composed of an alpha-olefin component having 3 to 20 carbon atoms and a cyclo-olefin component,(i) said copolymer containing 5 to 99 mole % of recurring units derived from said alpha-olefin component having 3 to 20 carbon atoms and 1 to 95 mole % of recurring units derived from said cyclo-olefin component, and(ii) said copolymer having an intrinsic viscosity [.eta.], measured in decalin at 135.degree. C., of from 0.01 to 10 dl/g; andan olefinic random copolymer composed of (A) an olefin component having 3 to 20 carbon atoms and (B) a cyclic polyene component and as required, (C) a cyclo-olefin component,(i) said copolymer containing 5 to 99 mole % of recurring units derived from said alpha-olefin component (A) having 3 to 20 carbon atoms and 1 to 95 mole % of recurring units derived from said cyclic polyene component (B) and 0 to 90 mole % of recurring units derived from said cyclo-olefin component (C), and(ii) said copolymer having an intrinsic viscosity [.eta.

Abstract: In accordance with the present invention, there are provided benzene-insoluble organoaluminum oxy-compounds having less than 10% in terms of Al atom of Al component dissolving in benzene kept at 60.degree. C. and less than 0.09 of a (D.sub.1260 /D.sub.1220) of an absorbance (D.sub.1260) at 1260 cm.sup.-1 to an absorbance (D.sub.1220) at 1220 cm.sup.-1, both obtained by infrared spectrophotometry, and also processes for preparing said benzene-insoluble organoaluminum oxy-compounds.

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 a high stereoregularity or a copolyolefin having a narrow composition distribution.

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 titaninum 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: A liquid modified ethylenic random copolymer selected from an epoxidization product of a liquid ethylenic random copolymer of ethylene and an alpha-olefin having 3 to 20 carbon atoms and a hydroxylation product of a liquid ethylenic random copolymer of ethylene and an alpha-olefin having 3 to 20 carbon atoms. The modified copolymer is characterized in that (i) the liquid modified ethylenic random copolymer has an ethylene component content of 10 to 85 mole % and an alpha-olefin component content of 15 to 90 mole %, (ii) in the .sup.13 C-NMR spectrum of the liquid modified ethylenic random copolymer, signals of .alpha..beta. and .beta..gamma.

Abstract: Disclosed is a molecularly oriented molded body of an ultra-high-molecular-weight ethylene/polyene copolymer having an intrinsic viscosity (.eta.) of at least 5 dl/g and such a content of a polyene that the number of molecules of the polyene is 0.01 to 15 on the average per 1000 carbon atoms, wherein the molded body shows at least two crystal fusion endothermic peaks when the measurement is conducted in the restraint state by using a differential scanning calorimeter, the molded body has at least one crystal fusion endothermic peak (Tp) at a temperature higher by at least 20.degree. C. than the inherent crystal fusion temperature (Tm) of the ultra-high-molecular-weight ethylene/polyene copolymer determined as the main fusion endothermic peak at the time of the second elevation of the temperature, and the quantity of heat based on said crystal fusion endothermic peak (Tp) is at least 15% based on the total fusion heat quantity.

Abstract: An injection-molding polyolefin composition suitable for obtaining an injection-molded article having excellent sliding property and excellent impact resistance and being free from delamination, said polyolefin composition being characterized in that(1) the composition consists substantially of an ultrahigh-molecular-weight polyolefin having an intrinsic viscosity of 10-40 dl/g as measured in decalin of 135.degree. C. and a low-molecular-weight to high-molecular-weight polyolefin having an intrinsic viscosity of 0.1-5 dl/g as measured in decalin of 135.degree. C.,(2) the ultrahigh-molecular-weight polyolefin is contained in the composition in an amount of 10-40% by weight based on the total weight of the ultrahigh-molecular-weight polyolefin and the low-molecular-weight to high-molecular-weight polyolefin,(3) the composition has an intrinsic viscosity [.eta.]c of 3.5-15 dl/g as measured in decalin of 135.degree. C.,(4) the composition has a melt torque T of 4.5 kg.

Abstract: A novel low-crystalline propylene random copolymer composition comprising[I] 60 to 95% by weight of a propylene random copolymer and[II] 5 to 40% by weight of a low-crystalline propylene random copolymerwhich has excellent heat-sealability, heat-seal imparting property, transparency and antiblocking property and containing a reduced amount of a hydrocarbon-soluble component, a process for production thereof, and polypropylene composite laminated structure having improved heat-sealability and heat seal strength at low temperatures.

Abstract: A process for producing a polymer or copolymer of an olefin which comprises polymerizing or copolymerizing at least one olefin with or without a diolefin in the presence of a catalyst composed of (A) a magnesium-containing solid titanium catalyst component containing magnesium, titanium, a halogen and an electron donor as essential ingredients and (B) an organoaluminum compound catalyst component; characterized in that(1) said catalyst further comprises (C) an organic silicon compound catalyst component having an Si--O--C or Si--N--C bond, and(2) said electron donor in the catalyst component (A) is a cyclic mono- or poly-ester such as diethyl cyclohexene-1,2-dicarboxylate, di-n-butyl 1,3-cyclohexadiene-1,2-dicarboxylate, diethyl furane-3,4-dicarboxylate, di-n-butyl 3,4-dihydro-2H-pyrane-5,6-dicarboxylate, diethyl ester of cyclohexene-1,6-dicarboxylic acid, and so on.

Abstract: A novel low-crystalline propylene random copolymer composition comprising[I] 60 to 95% by weight of a propylene random copolymer and[II] 5 to 40% by weight of a low-crystalline propylene random copolymerwhich has excellent heat-sealability, heat-seal imparting property, transparency and antiblocking property and containing a reduced amount of a hydrocarbon-soluble component, a process for production thereof, and polypropylene composite laminated structure having improved heat-sealability and heat seal strength at low temperatures.

Abstract: A process for producing a propylene block copolymer in the presence of a highly stereospecific olefin polymerization catalyst which comprises producing a crystalline polymer or copolymer of propylene in a first stage and random-copolymerizing propylene and another alpha-olefin in a mole ratio of from 10:90 to 90:10 in the presence of the propylene polymer or copolymer in a second stage; wherein in the random copolymerization, 0.0001 to 0.5 mole, per gram atom of aluminum in the catalyst, of an oxygen-containing compound being gaseous in a standard condition or 0.001 to 1 mole, per gram atom of aluminum in the catalyst, of an active hydrogen-containing compound being liquid or solid in a standard condition is fed into the random-copolymerization reaction system.

Abstract: A process for producing a polymer or copolymer of an olefin which comprises polymerizing or copolymerizing at least one olefin with or without a diolefin in the presence of a catalyst composed of (A) a magnesium-containing solid titanium catalyst component containing magnesium, titanium, a halogen and an electron donor as essential ingredients and (B) an organoaluminum compound catalyst component; characterized in that(1) said catalyst further comprises (C) an organic silicon compound catalyst component having an Si-O-C or Si-N-C bond, and(2) said electron donor in the catalyst component (A) is selected from the group consisting of a cyclic mono- or poly-ester such as, diethyl cyclohexene-1,2-dicarboxylate, diethyl furane-3,4-dicarboxylate, di-isobutyl pyrrole-2,3-dicarboxylate, diethyl cyclohexene-1,6-dicarboxylate, di-n-propyl 1,2-benzenediacetate, and n-butyl tetrahydrothiophene-2,3-dicarboxylate.

Abstract: A liquid ethylene-alpha-olefin random copolymer, characterized in that(a) it has an ethylene unit content of 10 to 85 mole % and an alpha-olefin unit content of 15 to 90 mole %,(b) it has a low molecular weight,(c) it has a narrow molecular weight distribution,(d) the dispersion of the ethylene units and alpha-olefin units in the polymer chain is in the advanced state, and(e) the directions of bonding of the alpha-olefin units in the polymer chain are nearly the same.The copolymer is prepared by copolymerizing ethylene and an alpha-olefin having 3 to 20 carbon atoms in the presence of a catalyst comprising a compound of a transition metal of Group IVb of the periodic table and an aluminoxane. The copolymer is very useful as a synthetic lubricant oil.

Abstract: A process for producing a chemically blended propylene polymer composition having an ethylene content ranging from 3 to 40% by weight and being greater than the weight of the rubbery propylene copolymer formed in stage (II) below, which comprises the following stages (I) and (II):(I) a first stage of polymerizing propylene containing 0 to 5 mole % of another olefin in the presence of a catalyst composed of (A) a solid titanium catalyst component consisting essentially of titanium, magnesium, halogen, and an electron donor, (B) an organoaluminum compound, and (C) an organic silicon compound having an Si--O--C bond or an Si--N--C bond to thereby form a crystalline propylene polymer or copolymer; and(II) a second stage of polymerizing propylene and ethylene, or propylene, ethylene and another olefin in the presence of the reaction product of the first stage and the same catalyst as used in the first stage to form a rubbery propylene copolymer and a crystalline ethylene polymer or copolymer.