Mitsubishi Chemical Corporation

Mitsubishi Chemical Industries Limited

Mitsubishi Kasei Corporation

Yumito Uehara

Yoshinori Suga

Nobuaki Goko

Takehiro Sagae

Yoshiyuki Ishihama

Yasuo Maruyama

Masayoshi Hasuo

Eiji Isobe

Genjiro Kakogawa

Yasuhiro Nishihara

Hisashi Kitada

Hideshige Kato

Nobuo Enokido

Yukitaka Goto

Motonori Ueda

Hidehito Kato

Nobuyuki Shimizu

Yukimasa Matsuda

Ryokichi Takashima

Hidetoshi Yamamoto

Kouzou Kitayama

Kiyotoshi Fujioka

Ethylene-&agr;-olefin copolymer

Polymerization of olefins

A particulate phyllosilicate mixture comprising a mixture containing a phyllosilicte belonging to the smectite group and a phyllosilicate belogning to the mica group, the phyllosilicate particle having a content of the phyllosilicate belonging to the smectite group of 0.1 to 50% by weight and optionally satisfying the following requirements (a) to (c):

A method for polymerizing olefins which comprises using a catalyst which comprises, as the essential components, (A) a metallocene-type transition metal compound and (B) at least one member selected from the group consisting of (1) an ion-exchanging layered compound other than a silicate and (2) an inorganic silicate, which is obtained by salt-treatment and/or acid-treatment and which has a water content of not higher than 1% by weight.

Method for polymerizing olefins using a novel catalyst

A catalyst for polymerizing an olefin, which comprises (A) a metallocene transition metal compound, (B) (1) an ion-exchanging layered compound other than a silicate or (2) an inorganic silicate prepared by treating a starting ion-exchanging layer compound other than a silicate or a starting silicate with a salt, an acid, or a combination thereof, said component (B) having a water content not higher than 1% by weight which is obtained by heat-dehydrating component (B) under an inert gas atmosphere or under reduced pressure, and (C) an organoaluminum compound.

Catalyst for polymerizing an olefin and method for polymerizing the

An ethylene homopolymer or copolymer comprising ethylene and not more than 10% by weight of an .alpha.-olefin having from 3 to 20 carbon atoms and a fuel tank obtained therefrom are disclosed, said ethylene homopolymer or copolymer having (1) an intrinsic viscosity [.eta.] of from 2 to 6 dl/g, (2) a density of from 0.945 to 0.970 g/cm.sup.3, (3) an R value of from 2.5 to 4, said R value being defined as a .sigma..sub.2 /.rho..sub.1 ratio, wherein .sigma..sub.1 and .sigma..sub.2 mean stress in elongation with a strain at 2 sec and 4 sec, respectively, under a flow at an elongational strain rate .epsilon. of 0.5 sec.sup.-1, and (4) a relationship between high-velocity impact strength (HRI-IZOD) measured at -30.degree. C. and a melt index under a load of 21.6 kg (HLMI) satisfying formula:

Ethylene polymer and fuel tank comprising the same

A process for producing a copolymer of propylene and other .alpha.-olefins in the presence of a catalyst comprising a titanium-containing solid catalyst component and an organoaluminum compound is disclosed. The process comprises (1) a first step in which propylene is homopolymerized or propylene and a minor proportion of other .alpha.-olefin are copolymerized to prepare polymer particles having a pore volume of from 0.15 to 0.30 cm.sup.3 /g, and (2) a second step in which propylene and other .alpha.-olefin are copolymerized in the presence of said polymer particles. The resulting propylene copolymer particles have improved fluidity and high bulk density.

Process for producing propylene copolymer

A method for producing a propylene-.alpha.-olefin block copolymer, which comprises polymerizing propylene in the presence of a catalyst and then polymerizing in a gas phase an .alpha.-olefin other than propylene, or propylene and other .alpha.-olefin without deactivating the catalyst, wherein at least one compound selected from the group consisting of an aromatic carboxylic acid ester, a phosphorous ester, an unsaturated dicarboxylic acid diester, an amine compound and an amide compound, is supplied to the latter gas phase polymerization system.

Method for producing a propylene-.alpha.-olefin block copolymer

A method for producing an .alpha.-olefin block copolymer, which comprises polymerizing propylene alone or together with a small amount of other .alpha.-olefin in the presence of a catalyst comprising a titanium-containing solid catalyst component and an organoaluminum compound, and then polymerizing the resulting propylene polymer with an .alpha.-olefin other than propylene, alone or together with propylene in a gas phase without deactivating the catalyst, characterized in that the gas phase polymerization is conducted in the presence of a siloxane or a polysiloxane in an amount of from 1.times.10.sup.-6 to 0.1 by weight ratio relative to the weight of said propylene polymer.

Method for producing an .alpha.-olefin block copolymer

A process for preparing solid titanium trichloride useful for the polymerization of an .alpha.-olefin, which comprises precipitating violet-colored fine solid particles of titanium trichloride at a temperature of not higher than 150.degree. C. from a liquid of titanium trichloride liquefied in the presence of an ether, characterized in that after the amount of the precipitated violet-colored fine solid particles of titanium trichloride reaches at least 80% based on the total amount of titanium trichloride in the system, titanium tetrachloride is added in an amount within a molar ratio of from 0.2 to 10 based on the total amount of titanium trichloride in the system, followed by aging at a temperature of from 60.degree. to 120.degree. C.

Process for preparing solid titanium trichloride useful for the

The present invention relates to a process for producing a polypropylene-ethylene block copolymer by a continuous multi-stage polymerization comprising a first stage in which polypropylene is polymerized in a first polymerization vessel in the presence of a propylene polymerization catalyst, and a second stage in which propylene and ethylene are copolymerized in a second polymerization vessel, wherein the polypropylene slurry discharged from the first polymerization vessel is supplied to a concentrator to separate said slurry into a concentrated polypropylene slurry and a supernatant liquid, the concentrated polypropylene slurry is then introduced through an upper part of a hydraulic sedimentation classifier to be contacted with a countercurrent of the upward flowing of the supernatant fluid introduced through a lower part of said classifier to obtain hydraulically sedimented polypropylene, and non-hydraulically sedimented polypropylene; the thus obtained hydraulically-sedimented polypropylene is then supplied to the second polymerization vessel or to a further propylene polymerization vessel and the non-hydraulically sedimented polypropylene is then recycled from the classifier to the first polymerization vessel. The present process produces a propylene-ethylene block copolymer having excellent characteristics of cold shortness and high impact strength.

Process for continuously producing propylene-ethylene block copolymer

Propylene is polymerized in the presence of a catalytic system of the type which comprises a solid titanium trichloride-based complex serving as a catalyst, said complex having an atomic ratio of aluminum to titanium in the range of below 0.15:1 and containing a complexing agent, and an organic aluminum compound of the general formula, AlR.sup.1.sub.n Cl.sub.3-n wherein R.sup.1 represents an n-propyl group or an n-hexyl group and n is a value of 1.95-2.10. The catalytic system may further comprise an electron-donor compound as a third catalytic component.

Process for polymerizing propylene

Propylene is polymerized in the presence of a catalytic system of the type which comprises a solid titanium trichloride-based complex serving as a catalyst, said complex having an atomic ratio of aluminum to titanium in the range of below 0.15:1 and containing a complexing agent, and an organic aluminium compound of the general formula, AlR.sub.n.sup.1 Cl.sub.3-n wherein R.sup.1 represents an n-propyl group or an n-hexyl group and n is a value of 1.95-2.10. The catalytic system may further comprise an electron-donor compound as a third catalytic component.

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Yokkaichi, Japan

Yumito Uehara