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:
Dec. 03, 1996
Filed:
Sep. 29, 1995
Junji Tsuchiya, Nakakubiki-gun, JP;
Katsuya Takemura, Nakakubiki-gun, JP;
Osamu Watanabe, Nakakubiki-gun, JP;
Yoshihumi Takeda, Nakakubiki-gun, JP;
Toshinobu Ishihara, Nakakubiki-gun, JP;
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A partially tert-butoxylated poly(p-hydroxystyrene) is prepared by subjecting poly(p-tert-butoxystyrene) to reaction of eliminating some of the tert-butoxy groups in an organic solvent at a temperature of 30.degree.-100.degree. C. in the presence of an acid catalyst at a molar ratio of acid catalyst/t-BuO group of from 0.050 to 2.0. During the elimination reaction, a change of solubility of the resulting partially tert-butoxylated poly(p-hydroxystyrene) is determined to calculate a degree of elimination of tert-butoxy groups. The reaction is terminated when a desired degree of elimination is reached. Through a simple process, partially tert-butoxylated poly(p-hydroxystyrene) having a well controlled t-BuO content is produced in high yields.