Kinetics of polyesterification and models, 2. Kinetics and mechanism of 1,1,1‐trimethylolpropane esterification by long‐chain carboxylic acids at technological conditions

Kinetics of 1,1,1‐trimethylolpropane esterification by long‐chain (C 4 —C 18 ) carboxylic acids has been followed by GLC, HPLC, 1 H‐NMR, and potentiometric titrimetry. The system composition evolution was established at technological conditions, i.e. molar ratio between 1/1 and 1/3 and temperatures between 160 and 205°C. The rate constants of the three involved consecutive reactions were determined according to the kinetic law which assumes a partial order of 1.5 with respect to the acid and 1.5 with respect to the alcohol. Once the three rate constants k 1 , k 2 , and k 3 are known by direct determination, a computer simulation for the esterification process has been carried out. The experimental variation of the component concentrations and the calculated values show a proper agreement, thus proving the selected kinetic model.