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:
Aug. 06, 1985
Filed:
Nov. 14, 1983
Gordon C Newland, Kingsport, TN (US);
William R Darnell, Weber City, VA (US);
Eastman Kodak Company, Rochester, NY (US);
Abstract
The present invention provides a novel process for preparing specified amorphous polycarbonate polyols. The process comprises reacting phosgene, a branched-chain polyhydric alcohol, and a straight chain polyhydric alcohol in the presence of a solvent and in the absence of a catalyst at a temperature of about 60.degree. to 100.degree. C., and then contacting the amorphous polycarbonate product in the reaction mixture with a catalytic amount of a tertiary amine at reflux temperature for a period of time of at least about 30 minutes. The straight chain polyhydric alcohol is employed in an amount of about 3 to 40 mole percent, based upon the total amount of polyhydric alcohol present in the reaction system. A preferred branched-chain polyhydric alcohol is neopentyl glycol, and a preferred straight chain polyhydric alcohol is 1,6-hexanediol. Preferred solvents are xylene and toluene, and preferred tertiary amines are triethylamine and pyridine.