Patent ID: 9090738
Filing Date: 2015-07-28
Classification: C08G

Abstract:
1. A method for producing a polyamide resin comprising: heating diamines composed of 1,9-nonanediamine and 2-methyl-1,8-octanediamine in a sealed vessel to a reaction temperature of from 180 to 240° C.; adding an oxalic acid diester to the heated diamines at the reaction temperature; conducting a polycondensation reaction in the sealed vessel to form a polyamide and an alcohol, whereby the polyamide maintains a solution state in the alcohol; wherein the pressure in the vessel rises to 0.95 MPa during the addition of oxalic acid diester to the diamines, and the pressure in the vessel further rises to 2.25 MPa after completing the addition of the oxalic acid diester to the diamines.