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:
Mar. 29, 1994
Filed:
Sep. 30, 1991
Stephen L Goldstein, Cheshire, CT (US);
Edward A Barsa, Cheshire, CT (US);
Olin Corporation, Cheshire, CT (US);
Abstract
This invention relates to a multi-step process for isolating a cyclotrimerized isocyanate from mixture containing said cyclotrimerized isocyanate plus an isocyanate oligomer which comprises the steps of: (a) contacting said mixture with a liquid solvent to provide a solvent-containing mixture, (b) extracting said solvent-containing mixture by liquid-liquid extraction to cause said solvent-containing mixture to elute into an extractate and a residue, wherein said extractate is a cyclotrimerized isocyanate that is essentially oligomer-free and is further characterized by having reduced viscosity relative to said solvent-containing mixture, and (c) separating uncyclotrimerized monomer from said extractate to provide a reduced viscosity trimer product that is essentially free of monomer. Also disclosed is the reduced-viscosity product produced by this process.