PROCESS FOR PREPARING PLASTICIZER BASED ON ESTERS OF MIXTURE OF DICARBOXYLIC ACIDS HAVING 4 TO 6 CARBON ATOMS Russian patent published in 1996 - IPC

FIELD: chemical industry. SUBSTANCE: the product: plasticizer composed of mixture of C₄-C₆- dicarboxylic acid esters, mp 160-190 C, pressure 2-3 mm Hg, flash temperature 180-182 C. Reagent 1: melt of dicarboxylic acids which results from the production of adipic acid and comprises 22-24% succinic acid, 42-46% glutaric acid, 30-38 adipic acid, 0.5-0.7 nitric acid and 0.5-3% unidentified impurities. Reagent 2: cyclohexanol. Reaction conditions: the acid to alcohol weight ratio is 1:3-3.5, the catalyst is tetrabutoxy titanium used in amount of 0.5-1.5% with respect to the weight of dicarboxylic acids, the temperature 140-180 C, and the process is conducted till water recovery completely ceases followed by removal of excess amount of alcohol by vacuum distillation and extraction of fraction having boiling point of 160-190 C, and neutralization. EFFECT: more efficient preparation process. 2 tbl