Wanhua Chemical applied for a patent for halogen-free flame-retardant polyester polyol. The patented technology can improve the flame-retardant performance.

News on December 13, 2023, according to the announcement of the State Intellectual Property Office, Wanhua Chemical Group Co., Ltd. applied for a patent titled “A halogen-free flame-retardant polyester polyol, preparation method and its “Application in Rigid Polyurethane Foam”, publication number CN117209734A, application date is September 2023.

The patent abstract shows that the present invention relates to a preparation method of halogen-free flame-retardant polyester polyol and its application in rigid polyurethane foam. The raw materials for the preparation of the halogen-free flame-retardant polyester polyol include in molar fraction: A) 120-160 mole parts of glycol; B) 30-90 mole parts of nitrogen-free dicarboxylic acid; C) 50-90 mole parts of nitrogen-containing dicarboxylic acid; D) 0.2-0.6 mole part of flame retardant . The halogen-free flame-retardant polyester polyol contains high nitrogen and benzene ring contents and has excellent flame-retardant properties. At the same time, the present invention uses eugenol, triethylamine, diphenylphosphonochloride and silane as raw materials to synthesize a eugenol-based phosphorus/silicon flame retardant, and physically blends it into polyester polyol to exert nitrogen, phosphorus and silicon. The synergistic flame retardant effect between these elements, the introduction of organic groups in the flame retardant also improves its compatibility with rigid polyurethane foam, and has less impact on the mechanical properties of polyurethane materials.