Summary of experience of imidazole curing agent

It has been more than one year since the powder was made Due to the different requirements of customers on the curing temperature, the curing agent has been thoroughly understood and a large number of samples have been tried Now briefly summarize my personal feelings The curing agent of imidazole is mainly used Because there are many modifiers, different kinds can meet the different needs of customers In the imidazole aspect, the number of mature ones has become four, and there are many kinds of series Including original series, CN series, CNS series, azine series, OK series, Hz series, etc   I think: O series of c17z, a series of c11z-a and 2mz-a, OK series of 2ma-ok are more suitable for powder coating, its curing temperature can be reduced to about 90 degrees, 2ma-ok needs more than 120, which is suitable for some substrate with low temperature resistance; c17z and c11z-a have good adhesion to substrate due to their long alkyl chain (more application in adhesive industry); curing products Good toughness, excellent electrical performance (can be used for insulating paint); given appropriate curing temperature or curing time, TG can be up to 160 degrees; the paint made has a long pot life and excellent storage stability (2ma-ok is the best, followed by 2mz-a, c11z-a, and c17z again); the yellowing degree is very light or not yellowing The imidazole curing agents in four countries have high purity, fine particle size and narrow particle size distribution Although the price is expensive, the amount of imidazole is small, generally within 2-5% can meet the curing requirements It can be used to make high-grade paint I have developed insulating paint with 2mz-a, and its performance is very good In addition, it can also be used for amines and anhydrides accelerators Different imidazole can achieve different curing speed and storage period The liquid anhydrides have never been used, but tetrahydrophthalic anhydrides have high activity, but they are easy to sublimate and have poor storage stability when they are processed at high temperature The main amines are dicyandiamide, which has low activity and needs high temperature curing, or adding more accelerants The coating has high water absorption and poor electrical and mechanical properties.