Advances in the solvent-free synthesis of fatty esters of starch

Synthesis of fatty acid esters of starch by an efficient method without org anic solvent is described. Fatty esters of potato starch (C-8 to C-18) as w ell as octanoated biopolymer of several starch sources were prepared by gel atinization of native starch with formic acid, followed by treatment with a cid chlorides (C-8 to C-18). Esterification was readily carried out under a stream of N-2 at a stirring rate of 500 rpm at 105 degrees C for a reactio n time of 40 min. The DS and yield of every starch esters were determined. The thermomechanical behavior of the different fatty-acid starch esters was characterized by DSC and tensile test. Their hydrophobic character was det ermined by the contact angle measure.