Preparation And Performance Research Of Color Solar Reflective Thermal Insulation Coatings

Solar reflective thermal insulation coatings is a kind of functional paint with highsolar reflectance and hemispherical emissivity which applied on the building’ surfaceto reduce temperature of surface. After decades of development, now solar reflectivethermal insulation coatings has been successfully applied in aerospace, construction,petrochemical, military, industry and other fields, whose obvious effects of energysaving has been widely recognized and accepted by the industry. But during in actualapplication, thermal insulation coatings get into some trouble. More than90%ofproducts are white or light color, which is difficult to meet the demand of modernarchitecture needing different color.According to the principle of solar reflective thermal insulation coatings andcolor theory, main influence factors are researched during preparation, such as typesand dosage of pigment, the kind of resin and the kind of functional fillers. Especiallythe influence of pigment’ kinds and dosages acting on properties such as properties ofcolor paste, coating colors, heat reflection properties is researched and tested.According to the experiment results, formulation is optimized and different variety ofcolor solar reflective thermal insulation coatings was prepared. This article hasdiscussed and tested thermal properties of color solar reflective thermal insulationcoatings including total solar reflectance, near infrared reflectance, hemisphericalemittance and simulative thermal insulation temperature difference. At the same time,properties difference between reflective thermal insulating coatings and commonexterior wall coatings is tested and compared.Experimental results show that, the kind and dosage of pigment is the mostinfluence factor during preparation of color solar reflective thermal insulationcoatings.Compared with common pigment such as iron oxide pigments, cold painthas higher heat reflection ratio, excellent weather resistance, heat resistance andchemical stability. Cold pigments, in other words is called inorganic compoundpigments which is the key materials to prepare color reflection thermal insulatingcoatings. Compared to other emulsion, exterior wall coating with silicon resin hasgood waterproof and breathable and weatherability properties. So silicon resin issuitable to prepare exterior wall paints especially high PVC(Pigment volumeconcentration) exterior wall paints. As an kind of new type functional filler, hollowglass beads was added to the coatings to enhance insulation function.Through analysis the results of experiment, we can find the most import index ofcolor solar reflective thermal insulation coatings is lightness value. The higher islightness value, its total solar reflectance and near infrared reflectance ratio is morehigher, corresponding simulative thermal insulation temperature difference is more larger. This article presented experience formula between lightness value, total solarreflectance and thermal insulation temperature difference. Compared with ordinaryexterior wall coatings, color solar reflective thermal insulation coatings have manyadvantages, such as higher heat reflection properties. For example, total solarreflectance of solar reflective thermal insulation coatings is3.2times than ordinaryexterior wall coating which has the same dark gray color. The number of near infraredreflectance can reach9.8times. The deeper the color, the bigger is temperaturedifference between two kinds of coatings, such as temperature difference of lightyellow is1.3℃, while temperature difference of dark gray is8.5℃.Above all, colorsolar reflective thermal insulation coatings have better aging resistance performance.