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:
Apr. 09, 2002
Filed:
Apr. 12, 2000
Applicant:
Inventors:
Assignee:
Ticona GmbH, , DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08F / ; C08F 6/00 ;
U.S. Cl.
CPC ...
C08F / ; C08F 6/00 ;
Abstract
The invention relates to a process for using nitric acid to oxidize polyarylene sulfide to polyarylene sulfoxide, oxidizing at least 98% of the sulfide groups of the polyarylene sulfide to sulfoxide groups. According to the invention polyarylene sulfide is treated with nitric acid at a concentration of from 60 to 80% with heating. The polyarylene sulfoxide prepared by the novel process can be used as an excellent chemical blowing agent for foaming thermoplastics.