Preparation And Properties Of Self-Cleaning And Heat-Insulated Coating

The basic heat-insulated theory, preparation technology and properties of the self-cleaning and heat-insulated coating were studied. The silicone and silicone emulsion, hydrophobic additive, were preparaed by the method of hydrolytic polymerization and emulsion polymerization, respectively. The technical factors and properties of the coating were optimized. The design mothod of the heat-insulated coating film was studied. Coating for self-cleaning and heat-insulated was also prepared by using the hydrophobic addtive and heat-insulated addtive. The results show here,(1) The best reaction condition determined by the change of film properties in life time with UV light irradiation are: the hydrolyzation temperature is 60℃, the reaction time is 60 minutes, the less amount of water is of benefit to increase the hydrophobic property, the film formed with high degree polymer is steady. Synthesized in this condition, the silicone film has best gas-permeability, transmissivity and durability.(2) The reaction factors optimized by orthogonal tests are: the emulsion polymerization temperature is 60 ℃, the reaction time is 3 hours, the amount of emulsifier is 8wt%, the hydrophile lipophile balance (HLB) value of emulsifier is 15, the stirring speed is 4000r/min, the dropping speed is 1.1g/min. By investigating the influence of drying temperature, it was found that the optimum drying temperature is differ from the base material, such as the drying temperature of Cu based film is 200 ℃, that of the glass based and aluminium based film is 240 ℃. Dried at the temperature, the film has surface with convex and concave microstructure, its hydrophobicity and surface roughness can be improved evidently by adding the bead-forming agent.(3) The self-cleaning and heat-insulated building coating with excellent hydrophobic property and gas-permeability was preparaed by using the hydrophobic additive, modified sepiolite and modified expanded pearlite. These additives have no adverse effect on the properties of the coating, and the optimum contents of them are: hydrophobic additive 6%, sepiolite 6% and expanded pearlite 3%. The best heat-insulated method can be realized with multi-technique heat-insulation.The self-cleaning and heat-insulated building coating obtained in this paper can be used onthe buildings and covering materials. It not only can protect the material, prolong its lifetime, but also has efficient self-cleaning function and heat-insulation property.