| 摘要 |
1,149,460. Esters of dicarboxylic acids and glycols. METALLGESELLSCHAFT A.G. 19 June, 1967 [21 June, 1966], No. 28242/67. Heading C2C. Esters of dicarboxylic acids with diols are produced continuously by reacting a dicarboxylic acid with an alkanol, reacting the mixture so formed with a diol to obtain a product which contains an ester of the dicarboxylic acid with the diol and also the alkanol, recovering the alkanol from the mixture and recirculating it for reaction with further amounts of dicarboxylic acid. The reaction is carried out at elevated temperature, e.g. 120-300‹ C. The process is particularly suitable for esterifying terephthalic acid with ethylene glycol using, preferably, methanol as the alkanol. In an example an ethylene glycol ester of terephthalic acid of formula HO(CH 2 CH 2 OOC-C 6 H 4 -COO) n CH 2 CH 2 OH in which n is 2-6 is prepared. |
