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:
Oct. 16, 1990
Filed:
Oct. 13, 1989
Genevieve Galland, Lyons, FR;
Jean Coquard, Grezieu la Varenne, FR;
Rhone-Poulenc Chimie, Courbevoie, FR;
Abstract
Amorphous (co)polyamides are polycondensed from aromatic dicarboxylic acid(s), e.g., isophthalic acid and/or terephthalic acid, and from aliphatic diamine(s), e.g., hexamethylenediamine, by preparing two unbalanced prepolymers of low viscosity, one containing excess COOH endgroups and the other containing excess NH.sub.2 endgroups, and then, in a second stage, the two unbalanced prepolymers are mixed in given proportions and their postcondensation is carried out in the molten state in a vented extruder including one or more screws; the amorphous (co)polyamides thus prepared are perfectly transparent and can be easily injection molded into useful shaped articles endowed with good properties, especially in respect of multiaxial impact.