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:
Apr. 02, 1996
Filed:
May. 26, 1995
Shin-Etsu Chemical Co., Ltd., Tokyo, JP;
Abstract
A novel method is disclosed for the preparation of a (meth)acryloxyalkyl group-containing organopolysiloxane having a linear structure by the ring-opening siloxane rearrangement polymerization reaction of a (meth)acryloxyalkyl group-containing cyclic organopolysiloxane oligomer either alone or in combination with a cyclic organopolysiloxane oligomer having no (meth)acryloxyalkyl groups. Different from conventional acidic catalyst, the reaction can be promoted by the use of a cation-exchange resin in the H.sup.+ form which can be readily removed from the polymerization mixture after completion of the polymerization reaction leaving no acidic matter which influences on the stability of the product. The catalytic efficiency of the cation-exchange resin can be further enhanced when the resin is, prior to contacting with the cyclic organopolysiloxane oligomer(s), impregnated or swollen with a polar organic solvent such as tetrahydrofuran.