The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 2017
Filed:
Oct. 24, 2014
Nof Corporation, Tokyo, JP;
Takuma Tsubusaki, Kawasaki, JP;
Yuji Yamamoto, Kawasaki, JP;
NOF CORPORATION, Tokyo, JP;
Abstract
A method of producing a medical polyoxypropylene polymer and a polyoxypropylene/polyoxyethylene block copolymer including (A) adding to a polyoxypropylene polymer which is obtained by ring-opening polymerization of propylene oxide to a starting substance having an active hydrogen reacting with the propylene oxide and contains allyl ether as an impurity, a tertiary alkoxide of alkali metal in an excess amount based on a molar number of the active hydrogen of the starting substance and heat treating at 115° C. or less to isomerize the allyl ether to propenyl ether; and (B) adding a mineral acid to the product obtained in step (A) to adjust pH to 4 or less and treating at 70° C. or less to hydrolyze the propenyl ether. Also disclosed is a method of producing a medical polyoxypropylene/polyoxyethylene block copolymer which includes performing ring-opening polymerization of ethylene oxide to the polyoxypropylene polymer obtained above.