How is the fire protection of building insulation materials difficult?

From last year to this year, several major fires have given rise to the thinking of the building insulation materials industry. Currently, the insulation materials sold in the Chinese market are still dominated by low-end products. In the face of western countries, many non-halogen, low-smoke, high-efficiency and environment-friendly insulation and flame-retardant materials are born each year. Whether in the research and development of insulation materials or in the promotion of product types and marketization, China is lagging behind. status.

Violent competition in the market intensified the cost of qualified insulation materials, scary insulation materials and building fire protection whether there is a contradiction? Is the better the material's insulation performance, the worse its fire performance? Experts said that there is no contradiction between the two, and the key lies in the cost. In order to improve the fireproof performance while maintaining good heat preservation and energy saving, it is necessary to add flame retardants and other materials. As a result, the cost will go up. Compared with ordinary materials, materials with superior heat preservation, energy saving, and fireproof properties may have prices that differ by several times.

For example, ordinary materials cost between two and three hundred yuan per cubic meter, and the price of a good material may become a thousand dollars. According to the current national conditions and economic development level, general construction developers may not be able to afford such high costs. The constraints of economic costs are the reason why many buildings use relatively cheap materials. In the event of a fire, ordinary materials are more flammable and cause greater losses. Therefore, in order to achieve the dual purposes of national inspection and acceptance of market solutions, some of the products submitted for inspection will be strictly produced according to the standard, and the rest of the products that have flowed to the market will be cut corners to reduce production costs.

There is an error in the way the country promotes the use of thermal insulation materials. Since 2001, compulsory domestic buildings have been used as external wall insulation. In 2007, it was stipulated that buildings that do not use external wall insulation should not be accepted. Buildings with other insulation methods should not be accepted by related departments. Implement a one-size-fits-all approach to promote the use of polyurethane foam. This has led developers to use the price of insulation materials as a selection criterion in order to reduce the cost of construction. Many inexpensive insulation materials with low fire resistance and even flammability are used in construction projects.

In recent years, the fire caused by the polyurethane foam of the exterior wall insulation has continued. The CPPCC National Committee member and Vice Chairman of the Shandong Provincial Federation of Industry and Commerce Zong Licheng submitted a proposal this year, recommending that the polyurethane foam insulation materials be not fully promoted. He suggested that it is not advisable to promote the use of polyurethane foam boards for exterior insulation and interior decoration of buildings in order to reduce the fire risk of buildings. All localities can use the thickening of the local frozen layer thickness, the middle of the wall sandwiched perlite, foam clips in the middle of the wall and other ways to achieve thermal insulation.

The key to non-combination of heat preservation and fire prevention without “fish and **” is national supervision Liu Weidong, general secretary of the Polyurethane Products Professional Committee of China Plastics Processing Industry Association, stated: “Although China started late in this field, some companies adopted molecular design and structure. Modifications and the addition of flame retardants and other technical means have enabled the production of polyurethane rigid foams with a flame retardant effect reaching the flame retardant level, and have also been applied in some building insulation projects.” To improve the flame retardancy of existing products, domestically Scholars and research institutes vigorously carried out technological research and continuously developed and launched new flame retardants. The more advanced methods such as the introduction of flame-retardant groups in the molecular structure of polyether polyols, the use of flame-retardant groups have a structure with no migration of components, long durability, and compatibility with the hard foam polyether polyol organic components. Strong characteristics, is expected to achieve better flame retardant effect.

According to Ye Shuhong, a senior engineer at the Institute of Construction Science of Shanghai Academy of Science and Technology, the institute has developed a new type of inorganic wall insulation technology. According to this technology, the wall of the new building will use "self-heating" aerated concrete and other thermal insulation wall materials. These materials can be made from industrial waste such as fly ash, which can both fire and environmental protection; and "self-insulation" layer inside and outside can be coated with a special thickness of about 2 cm of thermal insulation mortar, the formation of all the non-combustible inorganic composition " Sandwich biscuits have the same energy-efficient exterior wall; for the energy-saving renovation of existing buildings, they can be individually dressed in special insulation mortars.

The state should regulate the use of building insulation materials. At the same time, researchers must also do a lot of work in this process. They need to make unremitting efforts for the next step in the development of high-efficiency insulation and energy-saving fireproof materials. Although there are still some practical difficulties, as Zhang Xiong, director of the Institute of Building Materials at the University of Ho Chi Minh University, puts it, "Good insulation performance and fire prevention effects can be fully taken care of."