| abstract |
In the process, α, ω-dicarboxylic acids with 6-18 carbon atoms are presentnor phthalic anhydride esterifiedn4 to 12 carbon atoms, straight or branchednalkanols or a mixture of these alcoholsnso that the esterification is carried out at a temperature of 90 to 140 ° C,nContinue for 0.1 to 2 hours so that the pressurencontinuously reduce atmospheric pressuren100 torr, then to the reaction mixturenan acid catalyst and then between 100 and 180 ° Cnthe esterification is completed at 2-5 hoursnso that the pressure is continuously reduced by atmospheric pressurenpressure to 20 torr. |