Patent ID: 6075117
Filing Date: 2000-06-13
Classification: C08G

Abstract:
A process for producing polyamide comprising the steps of:a) reacting a dinitrile containing 2 to 20 carbon atoms with at least a stoichiometric amount of water in the presence of a dicarboxylic acid as the sole catalyst at a temperature from 200 to 300.degree. C. in a closed vessel under autogenous conditions substantially free of air for a time sufficient for at least 95 mole % of the dinitrile to undergo hydrolysis and form a hydrolysate;b) adding a diamine to said hydrolysate formed in step (a) wherein the amount of diamine is within 10 mole % of equimolar based on the starting amount of dinitrile;c) heating the hydrolysate and diamine mixture in the presence of water for a time sufficient to polymerize; and thend) recovering polyamide having a triamine content less than 1,000 ppm and improved melt stability.