Rigid polyurethane foam thermal insulation material for construction industry is an important branch of polyurethane industry. It is characterized by multi-purpose, thermal insulation, waterproof and other functions. This kind of product has been used in European construction industry for 40 years since 1960s. Some countries also take polyurethane as the insulation and waterproof material specified by the construction industry through legislation. In recent years, with the rapid development of China's building energy-saving market, polyurethane rigid foam thermal insulation products have been widely used in the field of building thermal insulation and waterproof, and have become one of the leading market heat preservation and energy-saving products. As an integrated material of building thermal insulation and waterproofing, rigid polyurethane foam breaks the traditional building materials' single function: Waterproof without heat preservation and heat preservation without waterproof. Once the waterproof layer leaks, the insulation layer will lose the insulation function. Compared with other single function thermal insulation or waterproof materials, rigid polyurethane foam has obvious advantages: 1. Rigid polyurethane foam has multiple functions of one material, and has many functions such as heat preservation, waterproof, sound insulation, vibration absorption, etc. 2. Excellent thermal insulation performance, it is the insulation material with the lowest thermal conductivity (≤ 0.024) and the highest thermal resistance among all building materials in China. The thermal conductivity is only half of that of EPS foamed polystyrene board. 3. Polyurethane rigid foam has a continuous and dense skin and close to 100% high-strength interconnected wall, which has ideal impermeability. Spraying method is used to achieve continuous waterproof and thermal insulation layer without joint, forming seamless roof and overall external wall insulation shell, with excellent waterproof and impermeability. 4. Super strong self-adhesive performance (without any intermediate bonding material), strong bonding with roof and external wall, good anti wind exposure and anti negative wind pressure performance; overall spraying construction, completely eliminating "hot spot" and "cold bridge"; flexible gradual change technology can effectively prevent the waterproof layer from cracking; mechanized operation, automatic batching, uniform quality, fast construction and short cycle. 5. Stable chemical properties, long service life, no pollution to the surrounding environment; self extinguishment of open flame, and only carbonization does not drip during combustion, and the size and shape of carbonization layer are basically unchanged, which can effectively block the entry of air, prevent the spread of fire, and have good fire safety performance. As the only new building material of heat preservation and waterproof integration, the application of polyurethane rigid foam insulation material in domestic construction industry is still in the initial stage. Fortunately, in order to accelerate the innovation of building thermal insulation materials and promote the popularization and application of rigid polyurethane foam in the field of building energy conservation, the Ministry of construction has specially set up a "polyurethane building energy conservation application promotion working group" to promote the application of polyurethane rigid foam thermal insulation and waterproof materials in domestic building energy-saving industry.