POLYURETHANE DERIVED FROM BIOMASS RESOURCES, METHOD FOR PRODUCING SAME, AND POLYESTER POLYOL DERIVED FROM BIOMASS RESOURCES

摘要

Disclosed is a novel polyester polyol for obtaining an environmentally friendly polyurethane that has excellent elongation degree and elastic modulus, while maintaining heat resistance, weather resistance and water resistance intrinsic to a polyurethane derived from a polyester polyol. The polyurethane reaction of this novel polyester polyol can be easily controlled. Also disclosed is a polyurethane which uses this novel polyester polyol. Specifically disclosed is a method for producing a polyurethane, which comprises at least a step wherein a polyester polyol is produced by causing a dicarboxylic acid and an aliphatic diol to react with each other and a step wherein the polyester polyol and a polyisocyanate compound are caused to react with each other. The method for producing a polyurethane is characterized in that: the dicarboxylic acid contains at least one component that is derived from biomass resources; the organic acid content in the dicarboxylic acid is more than 0 ppm but 1,000 ppm or less; and the pKa value of the organic acid at 25°C is 3.7 or less.