摘要 |
1,252,444. Aliphatic hydroxy esters. UNILEVER Ltd. 19 March, 1969 [21 March, 1968], No. 13776/68. Heading C2C. Aliphatic 8-hydroxy carboxylic acid esters are prepared by reacting a lactone monomer of an aliphatic 8-hydroxy carboxylic acid ester (6-24C) and a polyhydric alcohol in the presence of an acid catalyst to form at least 80% of the ester at equilibrium, and removing the acid catalyst before 10% of lactone polymer is formed. The lactones mentioned are #-decalactone, 8 - dodecalactone, 8 - octalactone, and 8-hexalactone and the alcohols are ethylene glycol, propane-1,3-diol, mannitol, sorbitol, erythritol and glycerine. The acid catalyst may be removed by washing an organic solution with brine and optical rotation is used to follow the process. |