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:
Sep. 11, 2001
Filed:
Dec. 02, 1999
Applicant:
Inventors:
Masaharu Takahashi, Annaka, JP;
Yutaka Hagiwara, Annaka, JP;
Assignee:
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29B 7/00 ; B29B 1/00 ; C08G 7/708 ;
U.S. Cl.
CPC ...
B29B 7/00 ; B29B 1/00 ; C08G 7/708 ;
Abstract
An organopolysiloxane gum is continuously prepared by (I) mixing at least one cyclopolysiloxane with an end capping agent, (II) feeding the mixture to a self-cleaning reactor along with an alkaline polymerization catalyst, and effecting polymerization at a temperature of 100 to 250° C. and under subatmospheric pressure, (III) continuously adding a neutralizing agent to the reaction mixture of step (II), thereby terminating the polymerization reaction, and (IV) continuously removing the cyclopolysiloxane and volatile components from the reaction mixture.