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:
Jul. 25, 1978
Filed:
Dec. 03, 1976
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
In the preparation and working up of a SiOC-linked polysiloxane/polycarbonate copolymer comprising reacting an .alpha.,.omega.-dihalogenopolysiloxane with an .alpha.,.omega.-dihydroxy-oligocarbonate in the presence of a tertiary amine and a solvent, and subsequently separating off the resulting copolymer from the reaction mixture additionally containing the amine, amine hydrochloride and organic solvent, the improvement which comprises subjecting the reaction mixture to steam distillation whereby the copolymer remains behind. Advantageously, the copolymer reaction solution is added to an aqueous solution having a pH of 7 to 8 whereby the amine and hydrogen chloride also distill over. If a surface active agent is present in the aqueous solution the product will be of very fine particle size.