Development of powder coating technology takes place in many segments of industrial manufacturing, new and better products are being developed to meet the needs of a demanding marketplace. There are the following trends in powder technology:
- lower cure temperature products
- enhanced surface flexibility
- enhanced application properties (flowing) and workability
- enhanced UV durability.
Thermosetting carboxylic polyesters and UV-curable solid unsaturated polyesters were synthesized.
Carboxylic polyesters were obtained from: neopentyl glycol, ethylene glycol, terephthalic acid, isophthalic acid, trimelitic anhydride.
Unsaturated polyesters were obtained from: neopentyl glycol, 1,6-hexanediol, terephthalic acid, maleic anhydride.
All polyesters were modified with nano-filler - montmorillonite (1-2 wt.%) in order to improve processing and application properties.
Conclusions:
1. All polyesters modified with nano-filler were more resistant from agglutinating during storage in comparsion to unmodified polyesters.
2. There was no difference in melting point, glass temperature, melt viscosity and curing time between modified and unmodified carboxylic polyesters.
3. Introducing of nano-filler to unsaturated polyesters resulted in increased glass temperature and melt viscosity with unchanged curing time and melting point. |