Route to new dimer acids

摘要

Fatty acid dimers are prepared by the dimerisation of oleic/linoleic acids, typically at high temperature (up to 250°C), high pressure (up to 300 psi) and in the presence of a catalyst. They have a number of application areas, including the preparation of polyamides for crosslinking epoxy resins. This paper describes the synthesis of a new fatty dicarboxylic acid half ester (abbreviated here as NFAHE) from the Diels Alder reaction of a methyl ester of a soya bean oil and sorbic acid. The process involves refluxing the methyl esters of soya bean oil with sorbic acid in cyclohexanone and lead oxide (at a temperature of 145-200°C). The reaction was monitored by regular iodine value tests. It is claimed that the end product (studied using mass spectroscopy) was obtained in greater than 90% yield.