Abstract: A method is described for producing saturated dicarboxylic acids with a chain length of C6 to C21 or the corresponding diamidic dicarboxylic acids from fatty acid cleavage of unsaturated fatty acids or the bis-fatty acid diamides of these unsaturated fatty acids by oxidative ozonolysis and subsequent separation and purification of the dicarboxylic acids, whereby after oxidative ozonolysis, the reaction products are dissolved at a high temperature in a carboxylic acid or a mixture of several carboxylic acids with a medium chain length of C6 to C12 or esters of short-chain alcohols of these carboxylic acids as the recrystallization solvent.

Abstract: A method is described for producing saturated dicarboxylic acids with a chain length of C6 to C21 or the corresponding diamidic dicarboxylic acids from fatty acid cleavage of unsaturated fatty acids or the bis-fatty acid diamides of these unsaturated fatty acids by oxidative ozonolysis and subsequent separation and purification of the dicarboxylic acids, whereby after oxidative ozonolysis, the reaction products are dissolved at a high temperature in a carboxylic acid or a mixture of several carboxylic acids with a medium chain length of C6 to C12 or esters of short-chain alcohols of these carboxylic acids as the recrystallization solvent.

Abstract: The present invention relates to a new kind of hydroxyfatty-acid-based monomers which are suited for producing plastics and which are obtained by reacting the esters of hydroxyl-group-containing fatty acids or the esters or salts of amino-group-containing fatty acids with appropriate bifunctional compounds that are capable of reacting with hydroxyl or amino groups, the reaction being such that always two molecules of such fatty acid esters are linked together via the hydroxyl groups or the amino groups by means of the bifunctional compound.