Patent ID: 6084056
Filing Date: 2000-07-04
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 from 0.1 to 1.3 mmoles of catalyst to one mole of said dinitrile and in the presence of from 0.01 to 0.5 moles of a dicarboxylic acid cocatalyst at a temperature from 200 to 300.degree. C. in the absence of air for a time sufficient for at least 95% 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 then(d) recovering polyamide having a triamine content of less than 1,000 ppm and improved melt stability.