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. 24, 1993
Filed:
Oct. 13, 1992
Applicant:
Inventors:
Richard R Cooper, Cleveland, GB;
David G Parker, Cleveland, GB;
Assignee:
Imperial Chemical Industries, PLC, Welwyn Garden City, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528174 ; 528171 ; 528391 ;
Abstract
A polyarylsulphone is prepared by the polycondensation of a bisphenol with an aryl dichloride, at least one of which contains a sulphone group, in the presence of a base and introducing into the reaction mixture less than 5% mole, relative to the aryl dichloride, of 4,4'-difluorodiphenylsulphone. The bisphenol and aryldichloride can be of 4,4'-dihydroxydiphenylsulphone and 4,4'-dichlorodiphenylsulphone respectively. The difluoro compound is added when the polymerisation is essentially complete. The polymer product if of improved quality.