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Polyurethane: from raw materials to market multi-point breakthrough

Over the past 40 years since the reform and opening up, China's polyurethane industry has made a series of brilliant achievements in raw material production and downstream market through independent innovation. From 1978 to 2018, China's annual production of polyurethane increased from 500 tons to 10 million tons.

Polyurethane materials, including polyurethane foam, elastomers, fibers, coatings, adhesives, leather, etc., are widely used in chemical industry, materials, construction, automobile, electronics, textiles and other fields. China began to produce foam resin in the 1960s, but then stagnated for a long time. In 1978, the national annual production capacity of polyurethane products was 11,000 tons, and the output was only 500 tons.

Lu congress, secretary-general of the China polyurethane industry association, said that due to the variety of raw materials needed to produce polyurethane, the production process is complex and long, especially the isocyanate production design nitrification reaction and photogasification reaction is dangerous, and there are many supporting raw materials. Restricted by various economic and technological levels at that time, there was no condition to build a complete industrial chain of polyurethane industry in China, and it was impossible to produce polyurethane products on a large scale.

2After 1980s, with the acceleration of opening up, China began to introduce foreign advanced polyurethane raw materials and products production technology and equipment, which played a good role in driving the development of domestic polyurethane industry. At that time, domestic scientific research institutions and enterprises also began to develop a series of products and special raw materials such as reactive injection molding, high-resilience cold-curing foam, polymer polyols, modified MDI and so on. By 1991, China's total production of polyurethane products had reached 150,000 tons, an increase of about 20 times over 1982. During the same period, the production of polyurethane raw materials also achieved great development. In 1978, one of the 22 projects approved by the state for introduction -- yantai synthetic leather factory introduced MDI production device. The TDI production line of 20,000 tons/year introduced by gansu yinguang chemical industry company passed the national acceptance in 1992. Polyether polyols form an annual capacity of more than 100,000 tons. This stage can be said to be China's polyurethane industry in the introduction of technology led by the rapid development of the start-up stage.

The 1990s is the rapid development period of polyurethane resin products brought by the great development of manufacturing industry. With the sustained and rapid development of national economy and tapped into a growing vitality of market reform and opening up, new polyurethane resin as a new type of multi-functional polymer materials in automobile, construction, refrigeration, heat preservation, furniture, metallurgy, mining, petrochemical, textile, etc for the wider application of the rapid growth of demand further stimulate the development of polyurethane industry. Soft foam box type foaming small business booming, refrigerator production base of automatic pouring hard foam insulation blanket production line, rigid sandwich panels pouring production line, the method of continuous large piece of soft foam line, soft foam molding line, a total of hundreds of thousands of tonnage to - such as polyurethane coatings, adhesives factory has more than a dozen. At this time, the country engaged in polyurethane products and machinery and equipment production, management, scientific research and development of thousands of units, there are also hundreds of large-scale. By 2000, the annual output of polyurethane products has reached 1.02 million tons, with an average annual growth rate of more than 25% from 1991 to 1998. However, during the same period, the development of polyurethane raw materials in China was relatively lagging behind. Gansu yinguang, cangzhou fertilizer plant and taiyuan fertilizer plant introduced small-scale TDI production devices, and most TDI, MDI and other polyurethane raw materials were still heavily dependent on imports, with the annual import volume rising sharply.

After more than ten years of research and experience accumulation, into the 21st century, with yantai wanhua as the representative, China's polyurethane production enterprises in the production scale, product categories, technical level and other fields began to make comprehensive breakthroughs, leading enterprises into the international arena. By 2017, there are five local isocyanate enterprises in China, including wanhua chemical, gansu yinguang, southeast dianhua, cangzhou dahua and yantai juli, among which wanhua chemical has 600,000 tons (yantai)+ 1.2 million tons (ningbo)MDI capacity, and has become a world-class polyurethane manufacturer with independent intellectual property rights. Polyether polyol production enterprises, mainly shandong dongda, cnooc shell, wanhua chemical.

At the same time, China has become the world's largest production base of polyurethane raw materials and the largest production and consumption market of polyurethane products. Polyurethane foam has become the most important variety of polyurethane materials, the output of which accounts for more than 50% of the total amount of polyurethane equipment products. Synthetic leather paste, sole solution, spandex, coating and other products also account for a large proportion, and its product output, consumption and export volume rank the first in the world. In 2017, China consumed 11.1 million tons of polyurethane products (including solvents) and 8.4 million tons of pure polyurethane resin.