Preparation of surfactants by condensation of fatty acid esters with hydrolyzed proteins

Abstract

AbstractProducts with good surface‐active properties can be easily prepared by condensation of fatty‐acid methyl esters with polypeptides derived from collagen proteins by hydrolysis. The condensation is done at moderate reaction temperatures (ca. 155 C) in dimethylsulfoxide solvent, and is promoted by sodium hydroxide or other alkaline reagents. The method works best with unsaturated esters, such as methyl oleate, which are more soluble in the reaction mixture, and which yield more soluble products, but also works well with the mixture of saturated and unsaturated fatty acid esters in methyl tallowate. The reaction appears to be a transamidation reaction in which incorporation of the fatty acid moiety results in partial cleavage of the polypeptide chain and in formation of methyl alcohol. Other solvents which can dissolve both fatty acid esters and collagen‐derived proteins, such as ethylene glycol, can be used to advantage in this reaction.