Mitsui Chemicals, Inc.

A School Corporation Kansai University

Takeshi Karino

Takayuki Onogi

Yasunori Yoshida

Masanobu Ajioka

Makoto Mitani

Mitsunobu Yoshida

Yoshiro Tajitsu

Kenichi Goto

Naoto Matsukawa

Yasushi Nakayama

Ichiro Fujio

Shinichi Usugi

Takeharu Isaki

Kenji Michiue

Fumiaki Nishino

Susumu Murata

Sei-ichi Ishii

Takaharu Isaki

Yoshiaki Aso

Noriyuki Katoh

Sei-Ichi Ishii

A method of production of ethylene-based polymer particles includes the steps of: homopolymerizing ethylene or copolymerizing ethylene and a linear or branched &#x3b1;-olefin having 3 to 20 carbon atoms in the presence of an olefin polymerization catalyst including: (A) fine particles having an average particle diameter greater than or equal to 1 nm and less than or equal to 300 nm obtained at least by the following two steps: (Step 1) causing contact between a metal halide and an alcohol in a hydrocarbon solvent; (Step 2) causing contact between a component obtained by (Step 1) and an organoaluminum compound and/or an organoaluminumoxy compound; and (B) a transition metal compound represented in General Formula (I) or (II), and (E) an intrinsic viscosity [&#x3b7;] of the ethylene-based polymer particles, measured in decalin at 135&#xb0; C., is from 5 to 50 dL/g.

Method of production of ethylene-based polymer particles and stretch-molded article obtained from ethylene-based polymer particles

The invention provides a piezoelectric polymer material including a helical chiral polymer having a weight average molecular weight of from 50,000 to 1,000,000 and having optical activity, the piezoelectric polymer material having a piezoelectric constant dat 25&#xb0; C. of 10 pC/N or more, a degree of crystallinity obtained by X-ray diffraction of from 40% to 80%, and a haze of from 0.5 to 30.

Piezoelectric polymer material, process for producing same, and piezoelectric element

A process for the production of polyolefin pellets by cuffing a raw material which contains a molten polyolefin resin and which is extruded from an extrusion orifice () of a die () into predetermined lengths with an underwater cutter () which is set in close vicinity to the die face of the die () and which rotates in water, satisfying the following requirements (A) to (C): (A) the average linear velocity (u) of the raw material passing through the extrusion orifice () as defined by the equation (Eq-1) is 50 to 650 mm/sec, (B) the fictitious aspect ratio (r) as defined by the equation (Eq-2) is 1.6 or below, and (C) the r/u value is 0.002 or above wherein Q is extrusion rate (mm/sec) of the raw material per extrusion orifice; R is radius (mm) of the extrusion orifice; and t is cutting time (sec) defined as an inverse number of the product of the number of revolution of the under-water cutter and the number of blades of the cutter.

Process for production of polyolefin pellets

An object of the invention is to provide copolymers which have a double bond in a side chain and are substantially free of unsaturated bonds in the main chain, copolymers which have a cyclic structure and are substantially free of unsaturated bonds in the main chain, and processes for economically synthesizing these copolymers.

Copolymer of olefin and conjugated diene, and process for producing the same

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Ichihara, Japan

Takeshi Karino