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. 10, 2001
Filed:
Nov. 16, 1999
Ronald James Hoxmeier, Houston, TX (US);
Shell Oil Company, Houston, TX (US);
Abstract
This invention is a solventless process for anionically polymerizing polysiloxane polymers. No volatile hydrocarbon solvent is used. A cyclic siloxane monomer and any comonomer are introduced into a molten polymer phase of a low molecular weight polymer that has a melting point within the polymerization temperature range for the cyclic siloxanes and the comonomer, for example, 30 to 80° C. which is the melting point range for polyethylene wax which is preferred. A non-volatile hydrocarbon oil with a melting point in this range may also be used, especially if a final polymer containing oil is desired. The cyclic siloxane monomer is anionically polymerized in the molten polymer phase or the oil at 30 to 150° C. Ethylene and styrene are preferred comonomers. The low molecular polymer or non-volatile oil is not separated from the polysiloxane after termination of the polymerization.