Method of preparing dimeric fatty acids and/or esters thereof containing low residual interesters and the resulting dimeric fatty acids and/or dimeric fatty esters

A method of preparing dimeric fatty acids and/or esters thereof having a low residual content of interesters comprising:

• a) dimerizing monomeric unsaturated fatty acids and/or esters thereof to provide a first mixture containing dimeric fatty acids and/or esters thereof, unreacted and/or rearranged monomeric fatty acids and/or esters thereof and interesters;
• b) separating the unreacted and/or rearranged monomeric fatty acids and/or esters thereof from the first mixture to provide a second mixture containing dimeric fatty acids and/or esters thereof and interesters;
• c) subjecting the second mixture to hydrolysis conditions to hydrolyze at least a portion of the interesters therein to monomeric fatty acids and alcohols thereby providing a third mixture containing dimeric fatty acids and/or esters thereof, monomeric fatty acids and alcohols;
• and
• d) separating monomeric fatty acids and alcohols from the third mixture to provide a dimeric fatty acid and/or dimeric fatty ester product having a reduced content of interesters relative to the interester content of the second mixture.