Pyrolysis Behavior and Thermostability of Sucrose Ester of Fatty Acids

Abstract

The pyrolysis behavior of sucrose esters of fatty acids having different carbon numbers of acyl group and degrees of esterification was investigated by programmed thermogravimetry (TG). The thermostability of the sucrose esters was also evaluated from the initial temperature of weight reduction in programmed TG and decomposition time from the initial to 5% weight reduction on isothermal TG.1) In the programmed TG of the sucrose esters, the initial temperature of the weight reduction increased with the number of carbons of the acyl group and decrease in the degree of esterification. Each sucrose ester showed unique pyrolysis behavior.2) In the isothermal TG, the thermostability of the sucrose monoacyl esters showed no relation to the number of carbons of the acyl group, and thermostability increased in the order of C14<C12<C18<C16. An examination of the thermostability of sucrose esters differing in degree of esterification indicated the monoacyl esters to possess greater thermostability than di- and triacyl esters below 180°C. The triacyl esters, however, showed more thermostability than mono- and diacyl esters above 180°C. However, the thermostability of sucrose penta- and heptaacyl esters was markedly less than that of mono-, di- and triacylesters at any temperature.