Correlation of Thermal History and Performance in Thermosetting Powder Coatings
Polymers and High Performance Materials
The heat history of thermosetting powder coatings necessitates careful control of extrusion conditions. It is common industrial practice to minimize pre-reactions by rapidly cooling powder extrudates. To some degree, the quenching process controls the formation of internal stress in the finished product. Similar stress development occurs when powder coated films are cured and cooled rapidly. This study examines polyester-blocked isocyanate, epoxy-dicyandiamide, polyester-triglycidyl isocyanurate epoxy-phenolic, and acrylic thermo-setting powder coatings via differential scanning calorimetry the glass transition temperatures, As a part of this study, panels were coated and cured at 150 degrees C for 30 min. Cooling was effected by either rapid or controlled annealing. Thermal, mechanical, and X-ray diffraction analysis data are presented which corroborate a thermal history dependence on powder coating performance.
Journal of Coatings Technology
Thames, S. F.
(1995). Correlation of Thermal History and Performance in Thermosetting Powder Coatings. Journal of Coatings Technology, 67(843), 23-27.
Available at: http://aquila.usm.edu/fac_pubs/5845