PU sandwich panel - the best insulation and energy saving material
MAY. 21, 2020
Polyurethane thermal insulation is an external wall materials with many advantages but encountered a lot of hinder in promotion. "At present, polyurethane accounts for less than 10% of exterior wall insulation materials in China, which is far lower than that in developed countries in Europe and America." "Polyurethane is the best building energy-saving material, but people's awareness of it is very limited, fire accidents happen, policy standards are not perfect, design units and construction units don't understand polyurethane insulation materials, low-cost fake and shoddy products flood the market, which leads to the misunderstanding on polyurethane, and hindering the development of polyurethance." pointed out by Li Zhiqiang, President of China Polyurethane Industry Association, at the China polyurethane exterior wall insulation application promotion meeting held in Jilin.
According to Zhu Changchun, in response to the call of national energy conservation and emission reduction, in order to comprehensively promote the application of polyurethane thermal insulation materials in the field of building energy conservation, so that the construction enterprises, relevant government units, developers, and ordinary people can better understand polyurethane products, China Polyurethane Industry Association has established "China polyurethane external wall thermal insulation application promotion group" in many provinces and cities across the country.
"There are three reasons for the difficulty in the application and promotion of polyurethane panel, mainly because we don't pay attention to the energy-saving effect, the acceptance standard is not clear, and the evaluation system is not scientific. There are some misunderstandings about polyurethane materials from all walks of life, an important reason is that polyurethane with a much higher price then polystyrene foam. " A person in charge of polyurethane material production enterprise told reporters. Although the subsequent maintenance cost of polyurethane insulation materials is low and the service life is long, the price of polyurethane is higher than that of polystyrene. At present, many architectural designs only stipulate the thickness of insulation materials, without considering the different thermal conductivity of different materials and the difference of subsequent maintenance cost. However, the thickness of insulation materials is often checked by the relevant departments during acceptance. Therefore, although most construction units know that polyurethane material has better heat preservation effect, they will also choose polystyrene material with relatively low price.
So where are polyurethane insulation materials used now? One is the buildings with high requirements for fire protection and thermal insulation performance, many places still can't accept the cost of polyurethane wall insulation materials. Some places are accustomed to using other materials.
At present, the external wall insulation industry in China, including polyurethane insulation materials, is still insufficient. The external wall insulation materials have not been popularized in China for a long time, and there is still a lack of application of basic theory and application basis. The advantages and disadvantages of all kinds of external wall insulation materials are different among enterprises.
"In foreign countries, due to the long service life of thermal insulation materials, research and evaluation methods are relatively systematic. For example, in Germany, a long-term tracking test method is adopted for the performance of thermal insulation materials. In our country, the external wall insulation materials are basically tested and verified in the factory or model room, as long as they do not fall off, they will be widely used in the project.
The material property, system performance and engineering quality of the external wall thermal insulation system are short of long-term verification under engineering conditions. We require that the thermal insulation material be used for 25 years, but after 5, 10 and 25 years, the performance of the material has not been tested yet. Therefore, China should establish a verification base for engineering conditions of the wall thermal insulation technology system suitable for China's national conditions. Carry out the basic concept research of engineering application, and take the data as reference for the anti crack, anti-seismic, waterproof, fire-proof and other performance of the external wall insulation system. "Because these conditions are not mature, the market competition is disordered. "
Although the performance is excellent, but the price is high, which makes polyurethane panel in a disadvantageous position in the market competition. In addition to increasing publicity and promotion, reducing the product cost naturally becomes the key to solve the problem.
The green building materials market is still in its infancy, and there is almost no threshold limit. For this reason, the exterior wall insulation products in the market are uneven. Obviously, the appearance is not very different, but the product quality is very different, which makes the high-end products unable to sell at the price. The market is completely occupied by low-price products, which can only be sold at the price of low-end products. As long as the formula proportion is slightly adjusted, the low-end products can be produced at a lower cost. Because the price is not dominant, the high-end and qualified products are in a passive position in the market, and many projects have little profit or even lose money.
This phenomenon has attracted the attention of the industry, "for enterprises that reduce costs through technological innovation, we welcome it, and for enterprises that are inferior, we should firmly resist it.". On the one hand, the industry should increase the publicity of its own products, on the other hand, it should also practice its internal skills. We have reported to the relevant departments, hoping to increase the supervision of the relevant industries, and at the same time, we advocate industry self-discipline, so as not to let individual enterprises damage the reputation of the industry. "
Due to the lack of industry supervision, many materials are not subject to aging test and performance test, resulting in the entry of materials with no guarantee of quality into the market. Therefore, we need to start from three aspects: first, strict market access, clear subject qualification, establishment of good faith archives; second, strengthening supervision, strengthening spot check re inspection, process supervision, publicity of application and results; third, advocating industry self Law, industry associations to strengthen guidance, enterprises should take the initiative to commit to the adoption of qualified products, while mutual supervision.
In addition, to strengthen the scientific design of the external wall insulation system, the construction can not be ignored. Yang Xiwei believes that China should carry out special training for the construction unit and the design unit, and the external wall insulation system of the building should carry out special design and professional construction. Designers and construction workers should learn and understand the external wall insulation technology, and launch design and construction professional qualification management at the right time.
With the increasing attention to building energy saving, polyurethane materials have entered the field of vision. The market demand for external wall insulation materials is also increasing, polyurethane panel have entered the field of vision.
We will improve the energy-saving standards of new buildings, carry out energy-saving renovation of existing buildings, vigorously develop green buildings, and promote green building materials.
As we are optimistic about polyurethane panel market, upstream and other polyurethane raw material manufacturers have expanded their production and built new projects to extend the industrial chain downward.
One of the main tasks of building energy saving is to enhance the insulation level of the external wall of the building, enforce the energy saving standard for the new building, and carry out the energy-saving transformation for the existing building, so as to improve the energy efficiency of the building. Building energy consumption accounts for about 30% of the total energy consumption of the society, which is an area with huge potential in the future energy-saving market. With the deepening of energy conservation and emission reduction in China, energy conservation work in the field of construction is gradually pushed forward.
The compulsory standard level of building energy conservation in China is low. Even though the "three-step" building energy conservation standard being implemented at present is only equivalent to the level of Germany in the early 1990s, the energy consumption index is twice that of Germany now. At present, the average insulation level of the external walls of civil buildings in China is only 1 / 3 of that of the developed countries in the same latitude in Europe.
In the field of existing buildings and new buildings, the thermal insulation potential of the external wall of civil buildings is also very huge. Such a huge market has attracted a variety of thermal insulation material manufacturers including rock wool, phenolic, polystyrene and polyurethane to participate in it. These products have their own advantages in energy saving and fire resistance, and the competition is also very fierce.
"PU panel is the exterior wall thermal insulation material with the lowest thermal conductivity and the best thermal insulation performance" is the most frequently mentioned sentence when the manufacturer introduces its products, and it is also one of the selling points of polyurethane sandwich panel.
In fact, the advantages of polyurethane wall panel are not only good thermal insulation performance, polyurethane wall panel has multiple advantages, not only low thermal conductivity, good thermal insulation performance, but also strong self adhesion, moisture-proof, waterproof, aging resistance, high temperature resistance, not easy to dissolve and other characteristics. At the same time, it has the advantages of light volume weight and high cutting accuracy. In terms of flame retardancy, polyurethane is a thermosetting thermal insulation material, which can achieve the flame retardancy of composite class B. it will not cause the phenomenon of droplet dissolution when burning, and it can avoid igniting other inflammables, showing good fire resistance.
It is estimated that the thermal insulation effect of 4cm thick polyurethane panel is equivalent to that of 17cm thick ordinary red brick. The thermal insulation effect is 2-3 times that of traditional rock wool and 2 times that of polystyrene panel. Adopting polyurethane panel can reduce the volume of thermal insulation material while ensuring the thermal insulation effect.
Although polyurethane insulation materials are widely used in refrigerators, freezers and other fields, but the market growth space is not large, and the growth rate of the market share of building insulation materials is amazing, which has become a new favorite of many polyurethane enterprises.
Why the market of polyurethane external wall panel is popularized, and the flammability is faltering?
Energy saving buildings in cities and towns in China only occupy 23% of the existing building area. We should actively promote the promotion and application of new materials, and accelerate the development of building insulation system and materials with the same service life as buildings, which integrate the functions of heat preservation, fire prevention, noise prevention and decoration. As a new type of thermal insulation material with excellent thermal insulation and energy-saving effect, polyurethane panel has been favored by the industry since its promotion. In particular, at the end of last year, the relevant departments abolished the requirement that civil buildings must adopt fire-proof A-level external insulation materials, which made some polyurethane insulation material manufacturers more than happy.