Cold winter, building roof, wall insulation has become the focus of attention.At present, China's annual new construction of nearly 2 billion square meters, more than all the sum of the amount of construction in developed countries, but more than 95% of the building is still high energy consumption. Mainly through the building, the outer envelope structure to take measures to reduce the indoor heat of the building to the outdoor distribution, maintaining indoor temperature.If the building put on a 'coat' - building insulation coating, either to create a comfortable Indoor thermal environment, but also to achieve the purpose of energy saving, is an effective means of building the 'warmth'.
Different principles to achieve thermal insulation
Building insulation coating through low thermal conductivity and high thermal resistance to achieve thermal insulation. Exterior insulation coating is divided into two categories, one is the thick outer insulation system, the use of heat transfer to reduce the barrier principle, such as powder polystyrene particles Insulation, inorganic glass beads insulation, the effect is obvious; the other is a thin coating, using the principle of reducing the absorption of sunlight to reduce the intrusion of outside solar energy, to achieve the purpose of insulation.According to the mechanism of thermal insulation can be heat insulation Insulation coatings are divided into barrier thermal insulation coating, reflective insulation coatings and radiation thermal insulation coating 3 categories.
Barrier insulation coating is through the low thermal conductivity and high thermal resistance to achieve a thermal insulation of a coating is the most widely used barrier thermal insulation coating is a composite silicate thermal insulation coating Such coatings are the 20th century Developed in the late 1980s, there are different product names, such as composite magnesium aluminum silicate insulation coating, rare earth insulation coating, coated composite silicate insulation coating, etc. It is made of inorganic and organic binder, separated Thermal aggregate (such as sepiolite, vermiculite, perlite, etc.) and air-entraining agent, etc. Although the thermal conductivity is low, the cost is low, but the long drying cycle, the impact resistance is weak.
Reflective insulation coatings are developed on the basis of aluminum reflective insulation coatings, by selecting the appropriate raw materials and formulations made of high-reflectivity coating, reflecting the sun to achieve the purpose of thermal insulation. Thin layer of reflective insulation Paint is the representative of such coatings.It is composed of the base material, heat-reflective filler and additives.Low thermal insulating reflective coating has high thermal reflectivity, generally more than 80%, obvious thermal insulation.But due to the coating thickness Thinner, with limited total heat resistance, little effect of heat preservation, can be used in combination with other insulation materials, and a new type of space-saving energy-saving reflective thermal insulation and insulation which integrates high efficiency, thin layer, thermal insulation, decoration, waterproof, fire prevention, Coating, can effectively inhibit the sun and infrared radiation heat and heat conduction, thermal insulation inhibition efficiency of up to 90%.
Radiation insulation coating is through the radiation in the form of buildings to the long-wave emission of solar energy emitted into the air, so as to achieve the effect of thermal insulation. Radiation insulation coatings in the form of heat radiation will be absorbed heat radiation to So that the interior insulation, insulation to achieve the effect of hot summer and winter for the area and the hot summer and cold winter area is a good choice, combined with the external insulation effect is better. As interior paint, low reflectivity at room temperature is conducive to Improve comfort and energy savings.
Technology keeps improving performance
In my opinion, should be based on the climate characteristics of different regions, formulate a program combining exterior insulation, reasonable selection and use of a variety of thermal insulation coating in our country, has been more mature and recommended exterior insulation system are: polybenzene Thin plaster exterior insulation system, adhesive powder polystyrene insulation slurry outside the wall insulation system, cast-in-place concrete composite network polystyrene board external insulation system, cast-in-place concrete composite polystyrene board steel wire mesh In addition, rockwool, polyurethane, extruded polystyrene board and other external wall insulation system also has some development and application in Europe and the United States At present, there are two kinds of thermal insulation materials: flame-retardant expanded polystyrene board and non-combustible rock wool board, both of which are used in the field of building energy conservation. Paint for the exterior layer.
With the development of society, the continuous improvement of living standards, continuous improvement of science and technology, the performance requirements of building insulation coatings are also rising.At present, relatively good exterior insulation coating has good weather resistance, low thermal conductivity, thermal insulation properties and stability , High softening coefficient, freeze-thaw resistance, anti-aging; base deformation adaptability, can effectively prevent the wall cracks; no cavity system, anti-negative wind pressure and strong, suitable for multi-storey and high-rise buildings; Good, strong respiratory function, both good waterproof function, but also discharge the insulation layer of water; construction convenient and fast, multi-point multi-level construction; fire rating up to B1 and above.
With the development of science and technology, some new insulation coatings are used in the construction.For example, there is a thermal insulation coating made of a special solution, the thermal conductivity of only 0.03 W / m. Simply paint a thin 3 mm in the interior of the building, The winter room temperature can be increased by 3 degrees C. Nano thermal insulation coating synthetic resin emulsion as a base material, adding high reflectivity, large thermal resistance of hollow ceramic powder insulation insulation coating made of its low thermal conductivity and reflection High rate, with good prospects for development.Using vacuum packing to prepare excellent performance insulation coating has also become one of the hot spots of current research.
R & D and production of composite multi-functional thermal insulation coating is also the future direction of development because a good thermal insulation effect of the paint is often the result of two or more thermal insulation mechanism of synergy results, a variety of thermal insulation coatings have Features, can be complex, to complement each other to develop excellent performance composite thermal insulation coating will be different thermal insulation coating and insulation materials, made of both thermal insulation and thermal insulation of the external wall insulation system, or Into the thermal insulation of the external wall insulation system to meet the hot summer and cold winter areas and hot summer and winter areas of building energy efficiency needs, but also the development trend of building exterior insulation.