Mitsui Chemicals, Inc.

Mitsui Petrochemical Industries, Ltd.

Tsuneo Yashiki

Mamoru Kioka

Shinichi Kojoh

Toshiyuki Tsutsui

Takashi Ueda

Masao Nakano

Masaki Kohyama

Hideki Sakai

Sadahiko Matsuura

Seiichi Ikeyama

Yoshinori Akana

Kazumitsu Kawakita

Masaya Yamada

Kenji Iwata

Shinichi Kojo

Yasuo Funabara

Satoshi Matsumoto

Shuji Minami

Disclosed is a solid titanium catalyst component which is obtained by a process comprising the steps of bringing (a) a liquid magnesium compound into contact with (b) a liquid titanium compound in the presence of (c) an organosilicon compound having no active hydrogen in an amount of 0.25 to 0.35 mol based on 1 mol of the magnesium compound (a), elevating the temperature of the resulting contact product to a temperature of 105 to 115&deg; C. and maintaining the contact product at this temperature. The contact product may be further brought into contact with not more than 0.5 mol of the organosilicon compound having no active hydrogen (c). Also disclosed are an ethylene polymerization catalyst formed from the solid titanium catalyst component and an organometallic compound and an ethylene polymerization process using the catalyst. By the use of the solid titanium catalyst component, ethylene can be polymerized with high activities and an ethylene polymer having excellent particle properties can be prepared.

Solid titanium catalyst component, ethylene polymerization catalyst containing the same, and ethylene polymerization process

A process for preparing an ethylene polymer composition comprises a step (I) to prepare an ethylene (co)polymer (i) having &lsqb;&eegr;&rsqb; of at least 1.5 times the intrinsic viscosity of a (co)polymer (ii) and a step (II) to prepare an ethylene (co)polymer (ii) having &lsqb;&eegr;&rsqb; of 0.3 to 3 dl/g, said steps (I) and (II) using a catalyst containing a component obtained by contacting a liquid Mg compound with a liquid Ti compound in the presence of an organosilicon compound, wherein the step (II) is carried out in the presence of the polymer (i) or the step (I) is carried out in the presence of the polymer (ii), to prepare an ethylene polymer composition having &lsqb;&eegr;&rsqb; of 1 to 6 dl/g and a density of not less than 0.94 g/cm . According to the invention, an ethylene polymer composition (particles) having excellent particle morphology, scarcely suffering sintering and having excellent moldability, a process for efficiently preparing the particles of ethylene polymer composition, and a film having small gauge-variation and excellent tear strength can be provided.

Process for preparing ethylene polymer composition, particles of ethylene polymer composition, and film obtained from the particles of ethylene polymer composition

Disclosed is a process for preparing a solid titanium catalyst component, comprising the steps of (I) contacting a liquid magnesium compound with a liquid titanium compound to precipitate a solid in the contact liquid (&bgr;), and adding an electron donor (d-i) selected from the group consisting of a polycarboxylic ester and a polyether compound to the contact liquid (&bgr;) during the time from beginning to end of the solid precipitation, to form a solid product (&agr;); and (II) contacting the solid product (&agr;) obtained after completion of the solid precipitation with an electron donor (d-ii) selected from the group consisting of a polycarboxylic ester and a polyether compound, to prepare a solid titanium catalyst component. According to the process, a solid titanium catalyst component capable of polymerizing an olefin with high activity and capable of preparing an olefin polymer of high stereoregularity can be prepared. Also disclosed are an olefin polymerization catalyst containing a solid titanium catalyst component obtained by the above process and an olefin polymerization process using the olefin polymerization catalyst.

Process for preparing solid titanium catalyst component, olefin polymerization catalyst, and olefin polymerization process

Solid titanium catalyst component and its use in olefin polymerization catalyst

Process for preparing solid titanium catalyst component for olefin

Disclosed is a titanium catalyst component for ethylene polymerization obtained by contacting [A] a solid magnesium aluminum complex containing magnesium, halogen, aluminum and an alkoxy group and/or alcohol having at least 6 carbon atoms, with [B] a tetravalent titanium compound. The solid magnesium aluminum complex [A] is obtained by contacting (a-1) a magnesium solution formed from a halogen-containing magnesium compound, an alcohol having at least 6 carbon atoms and a hydrocarbon solvent, with (a-2) an organoaluminum compound. Also disclosed is a process for ethylene polymerization comprising polymerizing ethylene or copolymerizing ethylene with an .alpha.-olefin having 3 to 20 carbon atoms in the presence of a catalyst for ethylene polymerization comprising [I] the above-mentioned titanium catalyst component for ethylene polymerization and [II] an organoaluminum compound catalyst component.

Titanium catalyst component for ethylene polymerization, ethylene

The present invention relates to a novel ethylene/pentene-1 copolymer whose molded film has a good balance between impact resistance and tear properties and high transparency, also is prominently reduced in a variation of the transparency even after subjected to a heat treatment, and further shows high blocking resistance, provided that the copolymer fulfills specific requisites. The invention also relates to a process for the preparation of the above-mentioned ethylene/pentene-1 copolymer and a formulation of the ethylene/pentene-1 copolymer composition using a stabilizer. According to the invention, there can be obtained an ethylene/pentene-1 copolymer composition which is excellent in heat stability in the molding stage, long-term heat stability and weatherability.

Ethylene/pentene-1 copolymer, and ethylene/pentene-1 copolymer

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Waki-cho, Japan

Tsuneo Yashiki