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. 07, 1992
Filed:
Jul. 11, 1990
Applicant:
Inventors:
Assignee:
Dow Corning Limited, Barry, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528 14 ; 528 18 ; 528 37 ;
Abstract
A method of making silethynyl-siloxane copolymers having R.sub.2 SiC.tbd.C units and R.sub.2 SiO units wherein each R denotes H or a C.sub.1-16 hydrocarbon or substituted hydrocarbon group, comprises ring-opening copolymerization in the presence of a catalytic amount of a lithium compound, of cyclic siloxanes and cyclic silethynyl polymers. Novel silethynyl-siloxane copolymers of the formula ##STR1## are also disclosed wherein R' denotes --C.tbd.CH or R and a and b are at least 1.