Mitsubishi Chemical Corporation

Kuraray Chemical Co., Ltd.

Kuraray Co., Ltd.

Japan Polychem Corporation

Eiji Tanaka

Hisao Urata

Toshiyuki Oshiki

Fumihiko Shimizu

Tetsuya Hanamoto

Fuminao Watanabe

Takayuki Aoshima

Naoshi Nakagawa

Takanori Kitamura

Hirofumi Nakamura

Hiroaki Fujii

Takeshi Okano

Shinji Iwade

Shinji Komori

Tadao Shiotani

Masanobu Abe

Tamio Higashi

Kiyoshi Yukawa

Glen H Ko

Kenji Mitsutani

Hong Sang Eui

Yasuhisa Mizuno

Lee Chang Woo

Yoshinao Shinohara

Ken Tanii

Yohichi Fujii

Syunji Katsuki

Park Young Min

Yasuhiro Kashiwagi

Yukihito Ohta

Jun Hosoi

Koshi Yokoyama

Riichirou Kawashima

Takeshi Matsuda

Miki Suzaki

Choi Yong Bok

A stable continuous production of a propylene-based block copolymer can proceed for a long time without causing accumulation of particles having a small diameter by a process having the following steps: (1) polymerizing an &agr;-olefin containing liquid propylene as a main component in the presence of hydrogen and a stereoregular polymerization catalyst in one or more polymerization reactors to obtain a polymer slurry; (2) feeding the polymer slurry to a copolymerization reactor; and (3) copolymerizing propylene and an &agr;-olefin other than propylene substantially in a gaseous phase in the presence of the stereoregular polymerization catalyst, the polymer slurry and a deactivating compound in the copolymerization reactor to obtain a propylene-block copolymer powder. The polymer slurry, discharged from one of said one or more polymerization reactors and is classified using a classification system to obtain a) a classified polymer slurry containing a large amount of particles having a small particle diameter and b) a classified polymer slurry containing a large amount of particles having a large particle diameter. A main part of the classified polymer slurry containing a large amount of particles having a small particle diameter is recycled to a final polymerization reactor of the one or more polymerization reactors.

Continuous production method of propylene-based block copolymer

Pipe made of polyethylene resin

The present invention provides a propylene block copolymer comprising polymer particles whose rubber-like component contents are 50% by weight or more, in an amount less than 1.0% by weight of the whole polymer particles finally discharged from a polymerization system.

Propylene block copolymer

A waste water treatment apparatus which is compact, and excellent in durability, has a high treatment performance and can stably operate for a long time is provided. In a waste water treatment apparatus at least comprising a waste water treatment tank in which a carrier particle immobilizing a microbe is charged and decomposing and eliminating an organic matter and/or an inorganic matter contained in a waste water, and a membrane module for filtrating a water to be treated which flows out from said treatment tank, a non-permeating water not passing thorough the membrane module is returned and circulated to said treatment tank. In a waste water treatment apparatus at least comprising a waste water treatment tank in which a carrier particle immobilizing a microbe is charged and decomposing and eliminating an organic matter and/or an inorganic matter contained in a waste water, a carrier immobilizing a microbe is an acetalized polyvinyl alcohol hydrogel.

Waste water treatment apparatus

A metal oxide-carrying activated carbon having an oxidation catalytic activity comprises a treated activated carbon obtained by carbonizing a carbon material, activating the obtained carbon with an activating gas comprising carbon dioxide and water vapor, said activating gas containing not more than 15% by volume of water vapor, and then cooling the activated carbon down to a temperature of not more than 300.degree. C. under the same atmosphere; and, carried thereon, 0.1 to 20% by weight as converted into metal of an oxide of at least one metal selected from the group consisting of iron, chromium, nickel, cobalt, manganese, zinc, copper, magnesium and calcium. A deodorant is obtained by adding 1 to 50 parts by weight of a plastic powder having an average particle diameter of 1 to 50 .mu.m to 100 parts by weight of the above metal oxide-carrying activated carbon. The above. activated carbon and deodorant exhibiting high decomposing functions for foul-odor gases such as methylmercaptan and trimethylamine and are hence usable as deodorants; they are also suitable as deodorants for refrigerators, since they have particularly high decomposing activities for these gases in low concentrations and at low temperatures.

Deodorant comprising metal oxide-carrying activated carbon

A process for continuously producing a propylene-based block copolymer having an excellent impact resistance of the present invention, comprises: a first polymerization step comprising polymerizing .alpha.-olefin comprising propylene in the presence of hydrogen and a stereoregular polymerization catalyst comprising a solid catalyst component containing magnesium, titanium, halogen atom and an electron-donor compound, an organoaluminum compound and, if required, an electron-donar compound in a single polymerization reactor; and a second polymerization step comprising transporting .alpha.-olefin polymer obtained in the first polymerization step to a copolymerization reactor and copolymerizing propylene with .alpha.-olefin other than propylene in a gas phase substantially in the presence of said stereoregular polymerization catalyst used in the first polymerization step.

Process for continuously producing propylene-based block copolymer

The disclosure describes a process for preparing .alpha.-olefin oligomers, which comprises carrying out oligomerization of an .alpha.-olefin in a solvent by reacting said .alpha.-olefin in a chromium-based catalyst system composed of a combination of at least a chromium compound, an amine or metal amide, and an alkylaluminum compound, in a contacting mode that the chromium compound and the alkylaluminum compound are not previously contacted with each other.

Process for producing .alpha.-olefin oligomers and .alpha.-olefin

A method for oligomerizing an .alpha.-olefin in the presence of a catalyst comprising a specific chromium compound including chromium atom and pyrrolyl group and an alkylaluminum compound, wherein the .alpha.-olefin is contacted to the chromium compound and the alkylaluminum compound without preliminarily contacting the chromium compound to either the .alpha.-olefin or the alkylaluminum compound.

Method for oligomerizing an .alpha.-olefin

Method for oligomerizing an alpha-olefin

A freshness keeping sheet comprises: 100 parts by weight of a palladium chloride-carrying activated carbon obtained by activating a carbon material under an atmosphere containing not more than 15% by volume of water vapor and cooling the activated carbon material to not more than 300.degree. C. under the same atmosphere and then permitting the resulting activated carbon to carry 0.1 to 10% by weight of palladium chloride, and 1 to 20 parts by weight of a synthetic fiber having a single fiber diameter of 1 to 30 .mu.m as a binder, said palladium chloride-carrying activated carbon and said synthetic fiber having been mixed and integrally molded into a sheet. The sheet can rapidly remove thin ethylene from a gas even at low temperatures and is hence excellent as a freshness keeping sheet for refrigerators and vegetables and fruits storing boxes.

Freshness keeping sheet

Provided are molded adsorbents comprising a mixture of adsorbent particles, fine plastic particles and a reinforcing fiber, the mixture having been molded utilizing the fine plastic particles and, as required, the reinforcing fiber as binder. They have features, as compared with conventional molded adsorbents utilizing a latex binder, having an adsorptive capacity having been decreased to a smaller extent from those of the raw material adsorbent particles used and higher adsorption rate owing to well-maintained porosity. They have good mechanical properties at normal temperature and can hence be processed by cutting or like machinings into various machine parts, including blades of fans having both adsorptive capacity and high mechanical properties. Also provided are a process for producing the above molded adsorbents and their use as deodorizing units.

Fan blade comprising adsorbent particles, fine plastic particles and

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Kurashiki, Japan

Eiji Tanaka