Preparation And Mechanisms Of Waterborne Solar Heat Reflecting Coatings Used On Metal

Metal corrosion would lead to large economic loss. Coating anticorrosion is the most effective, economic and widely used way to protect metal from corrosion. A new kind of coatings among various metalic coatings which can reflect solar heat has attached great importance to develop in recent years. The temperature raising of an objects on the ground because of adsorbing solar energy has been causing a lot of trouble for human life and industrial production. So developing anticorrosion coating with the function of reflecting solar heat is an important research topic. At the same time, developing environmental friendly coatings with higher performances has become the trends of coating industry.The objects of this research are making a kind of waterborne coatings which are effective anticorrosion, high efficacy in lowering the temperature, higher weather resistance. We have successfully made two types of anticorrosive metal coatings, e.g, coating of single and double composition.Research the changes of viscosity, hardness and gloss of two composition primer of epoxy latex after mixed reveals the mechanisms of curing reaction. The experimental results show that the curing reaction in multi-phase system is not complete and the controlling step is diffusion process. The pot-life of two composition epoxy latex can be observed by the index of coating gloss loss. The epoxy latex varnish is good at the performances of water-resistance, salt water-resistance, alkali resistance and against acid environment. The whole performances of epoxy latex 3560-W-50 and firming agent EPI-CURE^TM 8537-WY-60 are the best among five kinds of coatings sold on the market, and the film keeps fine after they were dipped in water or salt water for 120 h, and were dipped in 10%NaOH for over 500 h. Colored pigments of epoxy latex include red iron oxide, phosphorous excluder pigments, talc powder, barium sulfate and zeeospheres. The anticorrosive performances of coatings including zinc phosphate and trimeric aluminum phosphate are better than single pigment coatings. Zeeosphere has nearly no influences on coatings anticorrosive performances, otherwise, it can obviously increase the coating capability of heat insulation. To add zeeospheres after high speed stirring system can avoid the fracture of zeeospheres. Zeeosphere's weight in paints being 10%-15% is fit for its behaviors.