Inorganic material with better wear, hardness, flame retardant, insulation and other advantages, so as a structural material is favored by the people. However, its molding difficult; and the organic matter has the advantages of easy processing, good toughness etc.. Both composite will enable new material has the advantages of both organic and inorganic compounds. Because the nanometer material has special effect, nano inorganic material and organic resin hybrid variety performance greatly improve the film forming resin. The addition of inorganic nanoparticles in exterior architectural coatings, architectural coatings can enhance the high quality, high grade, environmental protection type, multifunction. Especially in Si02, Ti02 or Zn () blends together, to improve the coating of high ornamental, high weather resistance, high stain resistance of the great.
Si02 nanoparticles with unique optical properties of large particles do not possess, the existence of "blue shift" phenomenon, that is, the optical absorption edge shifted to short wavelength. The properties of nano Si02 particle has a strong UV absorption, infrared reflectance, which on the UVA UVA (320 ~ 400nm) reflectivity reaches 85%, the MW UVB (280 ~ 320nm) reflectivity of 80%, on short wave UVC (200 ~ 280nm) reflectance still amounted to 70% ~ 80%, so the Si02 nano particles for the system of building exterior wall coatings can improve the weatherability of coatings. In addition, Si02 nanoparticles with three-dimensional silica structure, large specific surface area, surface serious lack of coordination, showed strong activity. Therefore, the nano S1 2 particles () the adsorption force of pigment particles in the coating is very strong, the surface can be tightly coated on pigment particles, produce shielding effect, greatly reduced due to the irradiation of ultraviolet pigment decay and paint yellowing phenomenon.
General Ti02 has a certain ability to absorb ultraviolet radiation, and nano Ti02 as the particle size is smaller, more active, more ultraviolet absorbing ability. In addition, according to the Rayleigh theory of light scattering, nano Ti02 can through visible light and the scattered wave is shorter (200 ~ 400nm) ultraviolet light, therefore, the nano Ti02 can absorb and scatter ultraviolet, UV shielding ability of the strong. The performance of Ti02, Si02 or ZnO nanoparticles on coatings such as weather resistance, water resistance, alkali resistance and hiding power have synergistic effect.
The membrane material of main into pure acrylate or styrene acrylic emulsion for good performance, reasonable price; pigment nanoparticles Ti02, Si02 or Zn0; commonly used filler for light calcium carbonate, calcium carbonate, silk powder, precipitated calcium sulfate, kaolin or talcum powder; other additives have a thickening agent, dispersing agent, wetting agent, defoaming agent, antifreeze, film-forming agent, anti mildew fungicide, its role and the same ordinary latex paint for exterior wall.