Dimer Acid (Eshter-DA)

Dimer Acid (Eshter-DA) or dimerized fatty acids, are dicarboxylic acids prepared by dimerizing unsaturated fatty acids obtained from tall oil, usually on clay catalysts. Dimer acids are used primarily for synthesis of polyamide resins and polyamide hot melt adhesives. They are also used in alkyd resins, adhesives, surfactants, as fuel oil additives, lubricants, etc. It is a light yellow or yellow viscous transparent liquid.

Dimer acid usually contains predominantly a dimer of oleic acid. It is also called C36 dimer acid.

Dimer fatty acids are produced from different fatty acids by heating. Necessary are a fatty acid with conjugated double bonds or other unsaturated fatty acids. Examples of such fatty acids are conjugated linoleic acids. The reaction is carried out via Diels-Alder addition, whereby a partially unsaturated C6 ring is formed. Besides the dimer, trimers as well as (unreacted) monomers of the fatty acids may be present in the mixture.

Dimer acids can be converted to dimer amines by reaction with ammonia and subsequent reduction.

It can be used as raw material and surfactant for oilfield corrosion inhilbitor synthesis, and can also be used as lubricant,degreasing agent, fuel antirust agent and so on.

At present, it has been widely used in the fields of synthetic printed circuit board materials, ink production, rocket enginematerials and so on.

It is usually used to synthesize polyamide resin and polyamide curing agent, in which polyamide resin is mainly used as ink, paintadhesive and hot melt adhesive.