Study Of Hydrotalcite Heat-insulation Synergy And Application Of Waterborne Coatings

In this paper, hydrotalcite was used as main filler to prepare novel waterborne hydrotalcite heat-insulation coatings(WHHC). The effects of different fillers, single and two equivalent mixture on heat-insulation of WHHC were investigated. The device of heat-insulation performance was made by myself to test insulation temperature of each film, and studied the relationship of WHHC between composition / structure and heat-insulation performance. The results show that the insulation temperature difference ΔT of WHHC without other fillers can reach 21 ℃. Surprisingly, when WHHC was prepared from hydrotalcite combined with kaolin, its ΔT can increase up to 35℃. Further experiments confirmed that when WHHC was prepared from hydrotalcite mixed with the fillers which show good insulation effect, such as kaolin and titanium oxide, the heat insulation effect was enhanced, reflecting positive synergy effect of heat insulation. However, when WHHC was prepared from hydrotalcite mixed with the fillers which show poor insulation effect, such as calcium carbonate and barium sulfate, the heat insulation effect was dropped, manifesting negative synergy effect of heat insulation. In addition, by analyzing the relationship between particle size and heat insulation effect showed that if the particle size was smaller and its distribution was narrower, then the coating made by them will have better hiding power and insulation effect. Also discussed the impact of content and thickness of all fillers to the insulation effect of coatings, and the structure and properties of the coatings were characterized by FT-IR, UV-VIS and the ratio. The results show that WHHC prepared in thin film thickness can be achieved excellent insulation effect, and can also significantly reduce the surface temperature. This suggests that WHHC is expected to become a new class of high performance waterborne insulation coating.Based on this, composite waterborne heat-insulation coatings were prepared, and studied the effects of fillers content in the formulations on insulation properties. At the same time, by adding a variety of functional fillers explored whether they have good thermal insulation and adding different content to figure out its influences on insulation effect. Then investigated the effect of different colors on insulation coating, the results showed that the color-based paint insulation were greatly different from white paint. The insulation effect of light-colored paint can reach more than 16℃, but dark-colored paint is not satisfactory. This needs a lot of research to prepare a water-based pigment pastes which have excellent insulation effect, not only giving more colors of the water-based heat-insulation coating to provide thermal insulation function, but also combines colorful appearance to achieve functional and appearance of unity.