Polyurethane insulation materials open up a biological development route

2025/8/11 16:05:28

      Non-edible natural oils such as waste oils, woody oils, and rosin are used to replace petrochemical raw materials to design and develop new oil-based and rosin-based polyesters, polyether polyols, and rosin polyisocyanates that are comparable in quality to petrochemical products. Moreover, a bio-based composite flame-retardant system has been pioneered, and breakthroughs have been made in preparing a series of flame-retardant polyurethane foam insulation materials.

　　It is learned from the Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry that the innovation team led by researcher Zhou Yonghong has used non-edible natural oils such as waste oils, woody oils, and rosin to replace petrochemical raw materials, and designed and developed new oil-based and rosin-based polyesters, polyether polyols, and rosin polyisocyanates that are comparable in quality to petrochemical products. They have also pioneered a bio-based composite flame-retardant system and prepared a series of flame-retardant polyurethane foam insulation materials.

　　At present, substantial progress has been made in the promotion and application of the key technology for preparing polyurethane energy-saving insulation materials by replacing harmful raw materials with biomass developed by this innovation team. A 30,000-ton/year national largest biomass polyester polyol production line and a 20,000-ton/year domestic first oil-based polyester polyol continuous production line have been built in Jiangsu Qianglin Bioenergy Materials Co., Ltd. The achievements have been promoted to Jiangsu, Fujian and other provinces.

　　Polyurethane rigid foam is currently the best-performing thermal insulation material in the world, but traditional raw materials for producing polyurethane, such as phthalic anhydride, phthalic acid, and propylene oxide, are harmful to the environment and humans. Biomass polyurethane energy-saving insulation materials have prominent problems such as single product and technology, large gap in product quality compared with petrochemical products, poor flame retardancy, serious secondary pollution from reactions, and poor stability and controllability of production operations. To solve these problems simultaneously, Zhou Yonghong's innovation team focused their research on using biomass to replace harmful raw materials to prepare polyurethane energy-saving insulation materials with performance comparable to petrochemical products and good flame retardancy. This research has also received support from the National High-Tech Industry Development Project and the "948" Project of the State Forestry Administration.

　　Researcher Zhou Yonghong introduced that by independently developing a continuous reaction production device for oil-based polyester polyols, they have solved the problems of high energy consumption and serious leakage in traditional kettle and tank reactor production, greatly improving reaction efficiency and laying a foundation for industrial production. The new oil-based polyester polyols produced can completely replace petrochemical polyols without affecting the thermal insulation and dimensional stability of polyurethane products. At the same time, they have also developed new design and preparation technologies for rosin-based polyesters and polyether polyols. The biomass-based polyurethane rigid foam produced has good compressibility and tensile properties and can bond well with walls.

　　"Notably, we have for the first time used rosin polymerized dibasic acids, phenolic condensed dibasic acids, and small molecule polyols to react, developing new rosin-based polyesters and polyether polyols, which overcomes the fatal shortcoming of poor storage stability of polyester blends. We have also studied the creation technology of rosin polyisocyanates for polyurethane rigid foam. Through D-A addition reaction, amidation reaction of rosin, and reaction between amide and oxalyl chloride, fumaropimaric acid triacyl isocyanate is prepared, avoiding the traditional phosgene route with mild reaction conditions," said Zhou Yonghong.

　　On this basis, the R&D team has developed the flame-retardant technology for biomass-based polyurethane foam plastics for the first time, preparing composite flame-retardant biomass-based polyurethane rigid foam that meets the flame-retardant requirements of national standard B1 grade insulation materials.