The Influences of Pigments Figure on the Thermal Infrared Emissivity of Coatings

The particle figure and size of Al,Cu,Sn and Bi2O3 powders was changed through milling.With polyurethane(PU) and ternary polyethylene-co-propylene rubber(EPDM) as the binders,the coatings were prepared and the influences of pigments on the infrared emissivity of the pigments themselves and the coatings were studied.The results indicated that the particle figure and size of all pigments changed obviously by milling and its infrared emissivity was influenced respectively.In the coatings,the effect of pigment figure and size on the infrared emissivity was quite different from the influence on pigments themselves.When the figure and size of the pigments were propitious to the combination with the binder and the membrane-making,the infrared emittance of the coatings could be reduced effectively.