Dimer fatty acids
In dimer fatty acids is the oligomeric form of different unsaturated monomeric fatty acids . It is used in different areas, for example as a monomer for the production of polyamides , or as a plasticizing component in epoxy resins and polyester resins .
Dimer fatty acids are produced from different fatty acids by means of boiling. A fatty acid with conjugated double bonds ( conjuenic acid ) and other unsaturated fatty acids are required . Examples of such fatty acids are conjugated linoleic acids . The reaction takes place by means of Diels-Alder addition, which forms a partially unsaturated C 6 ring. In addition to the dimer, trimers and monomers of the fatty acids can also be present in a mixture.
The quality and consistency depends on the fluctuations in the properties of the natural raw materials. Dimer fatty acids are mixtures of substances.
It is typically a yellow liquid with a characteristic odor, the viscosity of which is 6700 mPa · s at 25 ° C. Dimer fatty acids are not classified as hazardous substances.
Dimer fatty acids are used in polyamides, polyesters and epoxy resins as plasticizing components. Reactions take place on the acid groups , the side chains in particular have a plasticizing effect. In addition to the properties in the solid film, dimer fatty acids also bring about some changes in behavior in the dissolved state. Polyamides, for example, are made compatible with solvents through higher proportions of dimer fatty acids. In addition, polyester resins and alkyd resins can be boiled with polyamides based on dimer fatty acids. This leads to a thixotropic effect of the binders obtained .
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- Datasheet dimer fatty acid vegetable from Syskem, accessed on July 1, 2018.
- InfoCard for Fatty acids, C18-unsatd., Dimers from the European Chemicals Agency (ECHA), accessed on July 1, 2018.