Preparation and performance of a waterborne UV/Al low infrared emissivity coating

Abstract

An Al powder filler, nano silica slurry and KH560 were mixed with a prepared waterborne UV-curable coating, and the coating was optimized by an orthogonal experiment. Influences of the Al powder concentration on the gloss, infrared emissivity, brightness, mechanical properties, corrosion resistance and other related properties of the coating were further discussed. The results show that the influence of the Al powder concentration on the gloss was more significant, followed by the UV curing time and nano silica slurry concentration. After studying the key role of the concentration of the Al powder, we found that as the concentration of the Al powder is augmented from 10.0% to 25.0%, the gloss lessened from 19.1% to 8.5%. As the concentration of the Al powder was augmented from 10.0% to 40.0%, the infrared emissivity lessened from 0.649 to 0.083 and the brightness L' value of the coating was step-by-step augmented and inclined to be stable; in addition, the coating's mechanical properties reached an excellent level. The coating containing 25.0% Al powder had the best corrosion resistance, surface morphology and comprehensive properties, which can potentially be used for infrared stealth technology.