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. 22, 1992
Filed:
Apr. 03, 1991
Applicant:
Inventors:
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08G / ;
U.S. Cl.
CPC ...
528348 ; 528179 ; 528182 ; 528183 ; 528185 ; 528335 ; 528336 ; 528340 ;
Abstract
There is described a process for preparing aromatic polyamides of high hydrolysis resistance by reacting aromatic diamines in a conventional organic solvent and in the presence or absence of inorganic salts wherein the diamine, which has a water content of up to 25% by weight, is dissolved in the organic solvent, which may likewise contain water, and the solution is subjected to a vacuum distillation until the water content of the bottom product is <100 ppm and subsequently the inorganic salts if necessary and then the dicarbonyl dichloride are added in a conventional manner and the condensation reaction is performed and concluded in a conventional manner.