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:
Sep. 16, 1986
Filed:
Dec. 20, 1985
Applicant:
Inventor:
Visweswara R Durvasula, Cheshire, CT (US);
Assignee:
The Dow Chemical Company, Midland, MI (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
568333 ;
Abstract
A method is described for autoxidizing a novel class of bis(ortho dialkyl-phenoxy)benzophenones directly to their corresponding dianhydrides. The method comprises autoxidizing the benzophenones in a solution of an aliphatic monocarboxylic acid having 3 to 8 carbon atoms with oxygen in the presence of a heavy metal oxidation catalyst and a promoter at a temperature of at least about 120.degree. C. to form the dianhydride. The dianhydrides are used in the preparation of organic high temperature polymers such as polyetherimides.