The Preparation Of Infrared Reflection & Thermal Insulation Coating Based On Organic-inorganic Compound Polymer Filming Materials

It is very necessary to improve the energy saving level for building consumption of the whole society by the way to reconstruct the energy saving system of the old buildings. It would have the direct energy saving effect for the above mentioned aim by coating a infrared reflection and thermal insulation（IRTI） layer on the exterior wall of building, which can obtain the difference of temperature（（35）T） through the wall lighted by sun more than 10 ℃. Usually the filming forming materials of IRTI coating are mainly consisted by organic polymers, and their durability will be decreased under the irradiation of sun light. This paper introduced the preparation of a new kind of IRTI coating materials with the promising durability and weather ability, and it was made by using the inorganic polymer and organic polymer compound as film forming materials（FFM）, and using the hollow glass beads（HGB） and rutile-type TiO₂ as functional fillers. The properties of resulting IRTI coating specimens are characterized systematically in terms of the thermal insulation and IR reflection, the weather ability, and the operational characteristics of them.In the preparation of inorganic polymer of metakaolin, it is found that the metakaolin specimen calcinated at 850℃ for 2 h had the more reactivity, and its inorganic polymer specimen excited by 15% Na2 Si O3 had the 7 d compressive strength of 15.5 MPa. Although the strength of the inorganic polymer is increased with the adding amount of Na2 Si O3 more than 15%, while the frost of alkali appeared on the surface and becoming brittle for the resulting hardened inorganic polymer specimens, which would degrade the volume stability of the IRTI coating with FFM film contained the inorganic polymer.The IRTI coating materials were prepared based on inorganic polymer（IP） of metakaolin and styrene-acrylic emulsion（OP） as compound FFM. In the preparation and characterization of their infra-red reflection and thermal insulation properties, as the m（IP）/m（OP）=0.3～1.0, the hardness and fragility of resulting FFM film are synchronously improved with the increasing of the mass ratio of IP to OP. As the m（IP）/m（OP）（29）1.0, the stability of storage at room temperature for FFM decreased. For the resulting IRTI coating specimens based on the FFM with m（IP）/m（OP） of 0.5, their properties of IR reflective and thermal insulation were varied with adding amount of TiO₂ and HGB to the maximum value. The maximum value of infrared reflective rate is 0.91 with TiO₂ mass fraction of 20%, and the maximum value of（35）T is 11℃ through the plate of calcium of silicate as the mass ratio of HGB to TiO₂ of 0.6. For the plate coated by IRTI coating only with TiO₂,（35）T reaches 3℃ as it is shined by iodine-tungsten lamp.