Hodogaya Chemical Co., Ltd.

Other

Desoto, Inc.

Kazuaki Okabe

Haruo Watanabe

Clive J Coady

Katsutoshi Igarashi

Shuichi Takeuchi

Hiroshi Nakaoka

Yoshio Matsumura

Hideyuki Ishii

Donald W Fieder

Ikuhiko Kanehira

Hiroyuki Tagawa

A method for producing a polyether-polyol having a narrow molecular weight distribution, which comprises carrying out selective fractional extraction of the low-molecular weight component from a polyether-polyol (A) having an average molecular weight of from 500 to 4500 represented by formula (1):HO&#x2014;[(CH)O]&#x2014;[(CRR)O]&#x2014;H&#x2003;&#x2003;(1)wherein Rand R, which may be the same or different, each represents a hydrogen atom or a linear or branched alkyl group having from 1 to 5 carbon atoms; n indicates a positive integer; p indicates an integer of from 1 to 8; and q indicates 0 or a positive integer, by the use of an aqueous solution (C) containing from 15 to 70 wt % sulfuric acid at a room temperature to 100&#xb0; C., to thereby suitably determine the amount of the aqueous sulfuric acid solution to the overall organic layer and the sulfuric acid concentration in accordance with the molecular weight and molecular weight distribution of the intended polyether-polyol to be fractionally extracted.

Method for producing polyether-polyol having narrow molecular weight distribution

Disclosed is a polyurethane resin having a broad rubbery-state region which has a number-average molecular weight of from 30,000 to 500,000 and comprises repeating units (A) represented by formula (I):

Thermoplastic polyurethane resin having broad rubbery-state region and

A radiation-curable coating composition adapted for the coating of optical glass fiber, comprising an ethylenically unsaturated polyurethane which is the reaction product of:

Composition for optical fiber coating comprising a polyether diol, a

A polyurethane resin composition without handling trouble is obtained by a combination of a copolyether polyol obtained by copolymerization of tetrahydrofuran and a 3-alkyl tetrahydrofuran at a mixing molar ratio of 85/15-20/80, a polyisocyanate compound and an active hydrogen atom-containing compound. The 3-alkyl tetrahydrofuran is preferably 3-methyl tetrahydrofuran.

Polyurethane from a copolyether of tetrahydrofuran and 3-alkyl

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Kanagawa, Japan

Kazuaki Okabe