Process for improving the stability of acetal polymers

摘要

The terminal hydroxyl groups of an acetal polymer are esterified or etherified by reaction with an end-capping agent chosen from anhydrides of carboxylic acids, orthoesters and orthocarbonates, by forming an intimate mixture of polymer in powder form and liquid end-capping agent, the amount of said agent in the mixture being less than that which results in loss of the free-flowing characteristics of the powder, and reacting said mixture under stirring at 50 DEG -170 DEG C.