Polymerisation of lactams to polyamides - in presence of metal oxide activators

摘要

Prepn. of polyamides comprises polymerisation of lactams in presence of metal oxides as activators, in amt. of 0.1-50 (5-20) wt. %. Polymerisation is carried out in air or an inert gaseous medium under vacuum down to 10-5 torr or pressure up to 3 atmos. and may be accelerated by exposure to ionising radiation. Reaction time is reduced compared with the usual hydrolytic process in presence of acid activators, and no breakdown of polymer occurs during processing. The one stage process simplifies mfr. and use of continuous working. High-pressure equipment is unnecessary and mechanical properties are improved, e.g. wear resistance by around 5 times. The polymer is simultaneously filled and coloured by the metal oxide.