Influences of morphology and floating rate of CeO2 fillers on controlling infrared emissivity of the epoxy-silicone resin based coatings

CeO 2 powders with flaky morphology and high floating rate are fabricated successfully by ball-milling and stearic acid modification. The influences of ball-milling time and surfactant stearic acid content on the morphology, floating rate, infrared emissivity of CeO 2 powders as well as the CeO 2 /epoxy-silicone coatings have been investigated systematically. The results show that the CeO 2 powders transform from irregular grains with larger size to flake grains with smaller size by ball-milling for 4 h. The floating rate of CeO 2 enhances from 0 cm 2 /g to 89.06 cm 2 /g by increasing stearic acid content from 0 wt% to 1 wt% while diminishes to 60.477 cm 2 /g with stearic acid content of 3 wt%. Ultimately, the coating with CeO 2 fillers ball-milled by 4 h and modified by 1 wt% of stearic acid exhibits the lowest emissivity value of 0.831 in the 8–14 μm waveband. The mechanisms for small and flaky fillers as well as high floating fillers to achieve low emissivity coatings are also fully revealed.