Introduction of three types of typical thermal insulation coatings

China Paint Online News
With the acceleration of urbanization and the increasing lack of energy, the state stipulates that since 2008, new homes must be insistinguated from insulation measures, and by 2015, the new green building area must reach more than 1 billion square meters. Under this policy, energy-saving building insulation materials are unique, its "representative" insulation coatings because of a variety of rich, and economical, practical and insulation is favored by people. Insulation coating is a new type of functional coating developed in recent years, which can be used on the surface of a building to reduce the internal temperature of a building and reduce energy consumption.
according to the insulation mode, insulation coatings are divided into barrier-type insulation coatings, reflective insulation coatings, radiation-type insulation coatings 3 types. , barrier-type insulation coatings
-blocking insulation coatings, is a thermal transmission of impedance to achieve thermal insulation passive cooling coatings. It generally uses low thermal conductivity compositions or introduces very low thermal conductivity air into the coating film for good thermal insulation. Barrier-type insulation coatings have the advantages of low accumulation density, low thermal conductivity, small dielemodyne constant and strong chemical corrosion resistance. It chooses a good weather resistance, good toughness, good membrane base, and supplemented by suitable dispersants, flame retardants, film-forming additives, etc., the insulation of the bone bonded together, coated to the surface of the equipment or wall, thus forming a certain thickness of insulation layer, in order to achieve thermal insulation function.
The more widely used barrier insulation coating is a silicate composite coating, which originated in the late 1980s and was originally made of loose sea bubbly as the primary raw material and water glass as the main adhesive. Later, in addition to the use of sea bubbly, but also added a large number of expanded pearl rock, expansion zircon, drift beads, coal ash, diatom soil, asbestos, glass cotton, mineral cotton, aluminum silicate fiber and so on. In addition, the adhesive used in it also transitions from a single water glass to gypsum (room temperature), cement (room temperature), high aluminum cement (medium temperature), silicone sol (high temperature) and other materials. At the same time, it also added a large number of advent agents to improve the performance of coatings, such as fluidity, hardening, water repugnant, high temperature resistance, reflectivity, etc. , after mechanical pulping, foaming, stirring and other processes to make paste-like insulation coating.
with the gradual improvement of people's living standards, as well as China's building insulation and energy-saving work policy guidance continues to strengthen, insulation coatings will be more used in the building interior wall insulation. Although the composite silicate insulation coating has been widely recognized and widely used, but there are some defects. Its main performance is: 1, drying cycle is long, construction by the season and climate, 2, weak impact resistance, 3, dry contraction, moisture absorption rate is large, 4, the wall bonding strength is low, if the construction is not easy to cause large areas of empty drum phenomenon; 5, decorative need to be further improved. Because of this, people also try to use paraffin to produce building insulation materials, paraffin microcapsulation to solve the problem of paraffin durability and environmental pollution. , reflective
-type insulation coating
by reflecting the visible and infrared form of light, the sun's light energy isolated paint is called reflective insulation coating. It can be seen from the solar spectral energy distribution curve that the vast majority of solar energy is in the visible and near-infrared regions, that is, the 400 to 1800nm range, accounting for about 95% of the solar radiation energy. In this wavelength range, the higher the reflectivity, the better the insulation of the coating. Therefore, by selecting suitable resin, metal or metal oxide pigments and production processes, a high reflectivity coating can be made to better reflect visible and infrared light for optimum thermal insulation.
in China, cooling and cooling equipment such as sprinklers, air conditioners, air conditioners and electric fans consume more than half of the total energy consumption throughout the year. The use of solar thermal reflection coatings, can overcome or alleviate the above problems, so the market prospects are broad. The research of this kind of coating is also hot, for example, water-based acrylic resin as the film substitut, with goldstone-type titanium dioxide, vanadium sulfate, hollow ceramic microbeads as insulation materials, the heat reflectivity of the preparation of reflective insulation coatings reached 92%, the reflectivity of infrared as high as 95%. Studies have shown that when the nano-titanium dioxide powder content is 3% and the reflective solar infrared factor CICP-L content is 4%, the insulation coating of the sun's infrared reflectivity is greater than 80%. Using silicone-modified acrylic resins, the researchers made a heat-insulated coating that withstands high temperatures, remained the same for 20 hours at 850 degrees C, and had a reflectivity greater than 80% on solar thermal radiation.
There are scientists to silicon propylene emulsion and other water-based polymer materials, by adding hollow ceramic particles and other functional fillers, to make a high thermal reflectivity to the sun, low thermal conductivity of insulation coatings, has been applied to the construction industry steel roof and glass curtain wall; In addition, it is also used in tanks, warships, rockets, spacecraft, etc., which greatly prevents heat transmission, reduces the surface temperature and internal ambient temperature of equipment exposed to solar thermal radiation, and greatly improves the work.Thye, radiation-type insulation coating
through the form of radiation, the building absorbs a certain wavelength of sun light and heat into the air, so as to achieve good insulation effect of the coating is called radiation insulation coating. It is well known that the infrared radiation of the atmosphere mainly comes from water vapor, carbon dioxide and ozone and suspended particulates in the atmosphere. In areas with wavelengths of 8 to 13 nm, water vapor and carbon dioxide absorption capacity is weak, which makes the atmosphere highly penetrating infrared radiation from 8 to 13.5 nm. Therefore, the building can radiate heat through this band. Because coatings have high emission rates in the 8 to 13.5nm band, substances with peak absorption values in this band must be added to enhance the radiation capacity of the radiation coating in this band. Infrared radiation absorbs radiant heat, which alters and aggravates the internal motion of the molecule, causing the particle energy state to produce thermal emissions from high to low, thus reducing the temperature of the radiation. The research shows that adding the appropriate amount of infrared powder to the coating can improve the radiation performance of the coating, make the coating have a high emission rate (e>0.9), and radiate the absorbed energy in the form of infrared radiation, thus playing a role in insulation.