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:
Nov. 19, 2013
Filed:
Nov. 02, 2010
Frederic Gubbels, Houtain-le-Val, BE;
Stephanie Lobry, Rombies et Marchipont, FR;
Francois Ganachaud, Decines, FR;
Amedee Ratsimihety, Montpellier, FR;
Frederic Gubbels, Houtain-le-Val, BE;
Stephanie Lobry, Rombies et Marchipont, FR;
Francois Ganachaud, Decines, FR;
Amedee Ratsimihety, Montpellier, FR;
Dow Corning Corporation, Midland, MI (US);
Abstract
The present invention relates to a process for the production of an intermediate siloxane monomer and use of said monomer to produce high molecular weight linear polysilalkylenesiloxanes. The siloxane monomer is prepared by ring opening polymerization of a cyclic monomer of the structure in the presence of an acidic or basic ring opening polymerization catalyst; to form a mixture of siloxane monomers and linear oligomers. The linear oligomers are then extracted and discarded before a further step of ring opening polymerization using the aforementioned intermediate siloxane monomer mixture as the starting material. The second polymerization step is undertaken at a temperature within the melting point range of said siloxane monomer mixture. The intermediate, final product and methods of their manufacture are described.