LINEAR VERY HIGH MOLECULAR WEIGHT POLYAMIDES AND PROCESS FOR PRODUCING THEM

摘要

PURPOSE: A linear very high molecular weight polyamide and a manufacturing method thereof from a lower molecular weight polyamide are provided for the polyamide to be used for manufacturing a high strength fiber and product. CONSTITUTION: A linear polyamide having a weight average molecular weight above 200,000 is made by heating a lower molecular weight molten polyamide with thorough mixing at a temperature of about 265-300°C for at least 5 minutes while an inert gas is swept gently through the reactor, the increase of molecular weight of the polyamide being catalyzed by a particular phosphinic acid derivative.