The hottest polyurethane intermediate industry is

Polyurethane intermediate industry has embarked on the road of renewable resources

with the rising price of oil, the price of raw materials for the production of polyester and polyether polyols has also risen rapidly. As a renewable resource, natural oil is used as raw material to produce polyurethane intermediates, and the cost advantage begins to appear. To this end, the national development and Reform Commission will develop a continuous production device with an annual output of 50000 tons of rosin and grease based polyester polyols, which will be included in the 2007 national major industrialization technology development project, and has now entered the installation stage

Zhou Yonghong, deputy director of the Institute of forestry chemical industry, Chinese Academy of Forestry Sciences, pointed out that after the completion of the project, the production of polyurethane (PU) intermediates is expected to replace toxic and harmful petrochemical raw materials on a large scale with woody grease, waste grease and pine resin, so as to drive the technological upgrading of polyurethane industry and improve the level of cleaner production process

rich natural oil resources

at present, the vast majority of raw materials and intermediates used in PU production come from mineral resources such as oil, coal and natural gas, and most of them are toxic and harmful chemicals such as phthalic anhydride, phthalic acid and propylene oxide. According to Zhou Yonghong, at present, the price of rosin is about 7000 yuan per ton, the price of oil is more than 6000 yuan per ton, the price of waste oil is about 4000 yuan/ton, the price of propylene oxide is as high as 15000 yuan per ton, and the price of phthalic anhydride is more than 10000 yuan per ton. Compared with polyester and polyether polyols produced from petrochemical raw materials, polyester polyols produced from natural oils have obvious advantages in cost, performance and environmental protection. Changing the production raw material route has become a major issue for the sustainable development of polyurethane industry

China has rich natural oil resources for realizing lighter and safer body design. Among them, the annual recoverable amount of rosin is more than 2million tons. At present, the output of rosin is about 800000 tons/year, ranking first in the world. Rosin and turpentine obtained from rosin processing are important chemical raw materials

at the same time, China also has the superior conditions to develop other woody oils. It is estimated that by 2015, the output of woody oil in China will exceed 10million tons. In addition, China produces about 5million tons of waste oils and fats such as oil residue recycled oils and municipal waste oils every year. Therefore, it will have good ecological performance and strong market competitiveness to produce polyurethane materials by using natural oils and fats such as cheap rosin, woody oil and waste oil, which can be operated flexibly and switched casually to replace or partially replace expensive petrochemical raw materials such as phthalic anhydride, phthalic acid and propylene oxide

the technical bottleneck has been overcome

although it is very feasible to produce polyurethane materials from natural oils and fats in terms of resources, there are still technical problems in the actual implementation

it is reported that fat based polyols are mainly produced by epoxidation of double bonds in the molecular chain of vegetable oil, and then hydroxylation. Due to the difficulty in separating double bond free vegetable oil molecules and epoxides, being used together as raw materials for hydroxylation reaction has a great impact on product performance, so it can not replace more parts by mass of petroleum polyester and polyether polyols. At present, liquid is still used in the synthesis of oil polyether polyols. At present, the research and development of color changing materials tends to diversify, acid-base catalysts, hydrogen peroxide and other epoxidation reagents, and the production process is seriously polluted

the Forest Chemical Industry Research Institute of the Chinese Academy of forestry, the only one in China that specializes in the chemical processing and utilization of forestry biomass resources, has been studying rosin polyester polyols and rigid polyurethane foams since the 1990s. By optimizing and improving the production process of rosin polyester polyols and foamed plastics in addition to high chemical resistance, product performance and polyurethane compatibility, they formed a unique process technology. In 2004, they took the lead in producing biodiesel and dimer at the same time, improving the economy of biodiesel

because dimer can replace phthalic anhydride and phthalic acid as the main raw materials for the production of polyester polyols, researchers have conducted a systematic study on the preparation of polyester polyols by transesterification of dimer, and established a pilot production line with an annual output of 500 tons of fat based polyester polyols. It is reported that the performance index of polyurethane products produced with natural oil has reached the level of petrochemical products

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