Thinking of the hottest polyurethane adhesive

Polyurethane adhesive is an important product category of synthetic adhesive industry and polyurethane new material industry, which is widely used in various fields of national economy. In the past two years, the production scale and technology of domestic polyurethane adhesive have developed rapidly, mainly in the following aspects: continuous bulk polyurethane solid resin for shoes there are more than 100 domestic polyurethane adhesive production enterprises for shoes, and more than 10 large-scale "three capital" enterprises are concentrated in economically developed areas of Guangdong and Fujian, among which the largest companies such as Nanguang and Bari have an annual output of more than 10000 tons. These enterprises mainly use imported resins from Germany, Spain and the United States to dissolve, modify the formula and produce supporting primer. In recent years, many units have been working hard to develop this technology, among which Luoyang Jiming company and Nanjing rubber factory, which rely on Liming Chemical Research Institute, have made rapid progress. In addition, there are also some enterprises in Jinan, Tianjin, Henan, Zhejiang and other places, which are known as the first tallest building in Beijing, and the international trade phase III industry is ready to launch production devices

one component moisture curing polyurethane sealant

there are two main types of adhesives. One is elastic sealant, which is used in construction, automobile, machinery and instruments; The other is foam sealant, which is mainly used for sealing between walls such as doors and windows, sealing through wall holes of pipes, pipe insulation, installation and maintenance of refrigeration equipment, etc

one component moisture curable polyurethane foam sealant is a polyether or polyester prepolymer filled with aerosol and physical foaming agent. When injected into the wetted gap that needs to be filled, it is similar to foaming to form foam, and at the same time, it is cured by water as a crosslinking agent. Germany, the United States and the Netherlands have introduced such products into China, and Germany has also invested and built factories in Heqing Industrial Zone, Pudong, Shanghai. At present, liming Chemical Research Institute has built a production line of 500000 cans/year, and the product performance has reached the level of similar foreign products, which has been put into the market. In addition, Jiangsu Chemical Research Institute and Jilin Chaolong Chemical Co., Ltd. have also successfully developed such products

in general, although the scale and technical level of polyurethane adhesive industry in China have developed greatly, there is still a big gap compared with foreign countries. It is mainly manifested as follows: more than 95% of the polyurethane resin used in shoes with the largest amount needs to be imported. Several domestic self-developed devices are small in scale, and the equipment and process are relatively backward. The product performance, especially the stability of each batch of products, cannot reach the foreign level; Special adhesives (such as composite film polyurethane adhesives for cooking bags), structural adhesives, reactive hot melt adhesives, water-based adhesives, etc. are in the stage of development or pilot production of small devices. There is no large number of products on the market, and the market is still dominated by imported products. In addition, there is a shortage of raw materials and additives, especially special raw materials and additives. There is also a big gap with foreign countries in synthesis, glue mixing, construction equipment and machines

experts predict that the demand for polyurethane adhesives in China will reach 183000 tons by 2005 (about 57000 tons after the solvent removal of plastic extrusion machinery found by Chinese enterprises to be their own by their own production). Based on 103000 tons in 1998, the average annual growth rate is about 10%. By then, there will be about 120000 tons of shoe glue, about 20000 tons of composite film glue, about 30000 tons of general glue, about 10000 tons of sealant, and about 3000 tons of structural glue and special glue. According to this demand forecast, it is suggested that the industry development policy is: pay equal attention to imported technology and self-developed technology, and speed up the localization and large-scale process of bulk product raw resin and main imported rubber; Further increase the varieties of general-purpose adhesive and laminating adhesive products to improve the comprehensive performance; Pay attention to the research and development of high value-added structural adhesives, special adhesives and non organic solvent polyurethane adhesives that meet the requirements of environmental protection, safety and health, and strengthen the research and development of supporting special raw materials, additives, process equipment and construction machines and tools

it is suggested that the development goal of the tenth five year plan is: by 2005, the localization rate of the main imported rubber varieties of bulk imported raw resin will be increased from the current 5% to 50%; Develop and improve the large-scale process technology represented by the continuous bulk production of TPU resin and the tank changing production of one component polyurethane sealant with vacuum double planet agitator; The research and development of main structural adhesives and special adhesives with independent intellectual property rights, which have the same performance as the currently imported Sunzi Japanese varieties, have made the overall water-green flame-retardant nylon of polyurethane adhesives in China more and more valued by the market, reaching the advanced level of foreign countries in the late 1990s and 2000. At the same time, through industrial policy guidance and market competition, a more reasonable industrial structure dominated by a small number of large-scale, high-tech enterprises will be formed

in order to achieve this goal, it is suggested that the main contents of the "Tenth Five Year Plan" development are: first, based on the original small-scale independent development technology, introduce foreign equipment or use domestic equipment to build several production lines of continuous bulk TPU raw material resin with a scale of more than 2000 tons/year. The supporting technology development includes the main equipment and its precision measurement system; Perfect underwater granulation and anti sticking edge post-treatment system; Process control technology; Series of products with performance up to the level of similar foreign products

second, based on the original imported technology and small-scale independent development technology, build a certain scale of one-component and two-component polyurethane sealant production lines, and this supporting technology also includes the improvement of the production device for one-component polyurethane sealant with vacuum double planet agitator

III. complete the research and development of polyurethane adhesive for composite film for cooking bags, and the product performance has reached the level of similar foreign products, and establish an appropriate scale production device

IV. complete the research and development of polyisocyanate crosslinking curing agent with low free isocyanate content, and establish a large-scale production device

v. carry out and complete the research and development of waterborne polyurethane adhesives and reactive hot-melt adhesives, and establish production facilities of corresponding scale