Research on Two-step Synthesis Method of 12-Hydroxystearate Diethanolamide

12-hydroxystearate diethanolamine, an intermediate for a leather fatliquoring agent, was prepared by two-step synthesis of amidation reaction and ammonolysis reaction through vacuum distillation dehydration, using 12-hydroxystearic acid and diethanolamine as raw materials. Through single factor experiments, the optimised synthesis conditions were determined as follows: the molar ratio of 12-hydroxystearic acid to diethanolamine was 1:1.03, and the temperature of the first amidation reaction was 135 degrees C and the reaction time was 4 hours. In the second step of ammonolysis reaction, the reaction temperature was 70 degrees C, the amount of sodium ethylate (sodium ethoxide) used as catalyst was 1.5% of the mass of 12-hydroxystearic acid, and the reaction time was 2 hours. Under the optimised conditions, the yield of the product could reach 90.9%. The structures of 12- hydroxystearate diethanolamide were characterised by FTIR spectrum.