The Development Of Biomimetic Self-cleaning Exterior Wall Paint

This paper described the mechanism of the exterior wall pollution and the self- cleaning theory of the lotus leaf. A novel paint that can from a film characterized by water repellent self-cleaning property has been developed. The film properties affected by the emulsions, pigments or additives were also described.Waterborns have been experiencing technological growth for the past 30 years, latex paint especially the exterior paint is very popular at present since the environmental concern were highlighted. Using waterborns as exterior coating is an orientation for building coating development, self-cleaning exterior wall paint will be applied widely because of its unique properties.During the experiment process, potassium persulfate acted as initiator. Nonionic and anionic surfactants were mixed , acting as emulsifiers. Semibatch seed emulsion polymeric technics was used to develop silicone-acrylic co-polymer emulsion. Then organosilicon-modified acrylate emulsion with high performances was developed by the technique. In this paper the effects of many factors on performances of emulsion and film were discussed, such as polymerization temperature, initiator content etc. The origanosilicon acrylic latex was an exterior paint binder with excellent weather durability and contamination resistance. The influences of emulsifiers such as the concentration of emulsifier, the ratio of anionic to nonionic emulsifier etc on the storage stability and Ca²⁺ stability were researched.Experimental results showed that glass transition temperature of latex polymers will be increased if acrylate emulsion was modified by organic siloxanes. At the same time film performances in water resistance, chemical resistance and heat resistance would also be increased greatly. But the content of organic siloxanes had to be of the right quantity because emulsion stability decreased when the quantity of organic siloxanes was too much and hydrolyzed and polymerized within organic siloxanes. The structures and properties of silane-acrylate copolymer had been characterized by means of TEM, SEM, and the properties of latex paints had been determined according to GB/T9755-1995 (Standards for Testing...