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. 12, 1985
Filed:
Dec. 05, 1983
Applicant:
Inventor:
Stephen M Cooper, Pittsfield, MA (US);
Assignee:
General Electric Company, Pittsfield, MA (US);
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528185 ; 528125 ; 528126 ; 528128 ; 528172 ; 528179 ;
Abstract
Copolyetherimides having random units in the structure and characterized by good transparency after molding are prepared by a process in which a dianhydride and a diamine are reacted at a temperature of at least 100.degree. C. to initiate polymerization, followed by the addition of a second anhydride and continuing the polymerization at the elevated temperature. Preferred features include conducting the reaction in a solvent and in the presence of a chain stopper, such as phthalic anhydride.