Preparation And Characterization Of Two Component Polyurethane Infrared Blocking Glass Coating

It is found that the proportion of building energy consumption is30～40%of overall energy consumption, approximately45%of which is caused by heating, air conditioning and refrigeration. Currently hollow glass and some transparent insulation film on the glass can block the sun’s heat radiation, but generally having disadvantages like low visible light, costly restrictions and difficulties in the practical application. Therefore, new transparent insulation coating with special optical properties was prepared and had remarkable advantages, such as high visible light transmittance, excellent insulation properties and low cost.This research started with the studying of the dispersity of the nano Antimony Tin Oxide (ATO)/Tungsten Trioxide (WO3) powders, and three coatings were prepared (nano ATO/two-component polyurethane, nano WO3/two-component waterborne polyurethane and ATO-WO3/two-component waterborne polyurethane). PH, dispersant and grinding methods and other factors were studied to find out how they effected on ATO aqueous slurry and WO3aqueous slurry by means of spectrophotometer, laser particle size analyzer and field emission scanning electron microscopy. It was shown that ATO aqueous-slurry Zeta potential is higher with pH value in the range of9to11. Dow963ATO can significantly improve the dispersion of the slurry. By using ultrasonic dispersion and decentralization of the milling, the particle size of nano-powders obtained mainly distributed in the range of40-90nm, reaching the nano-level requirements. The experiments also show that WO3aqueous-slurry Zeta potential is higher with in the range of8to10, using the same dispersion of ATO dispersion method to obtain a good dispersion of WO3aqueous dispersion having a particle size distribution of30-90nm.In this paper, three systems of thermal insulation nano glass coating were made, namely ATO/two-component waterborne polyurethane coatings, WO3/two-component waterborne polyurethane coatings and ATO-WO3/two-component waterborne polyurethane coatings. The effects of different nano-powder types and different nano-powder content on the mechanical properties, optical properties, water absorption and thermal insulation properties of the material were researched. UV-visible-near infrared (UV-VIS-NIR) spectrometer and thermal performance testing devices were used to discuss the ATO nano and nano-WO3shielding mechanism of the near-infrared. By the discovery of its mechanism of heat, we found ATO primarily shielded the infrared ray heat by absorption, while WO3shielded the infrared ray heat by co-action of absorption and reflection. Increasing the content of nano-powder in film can improve thermal performance. By testing different ratio of nano WO3and nano ATO, finally transparent coatings with excellent insulation properties was achieved and the thermal insulation property was improved by22%.