Carboxymethyl starch octenylsuccinate: Microwave- and ultrasound-assisted synthesis and properties

The synthesis of water-soluble octenylsuccinates of carboxymethyl starch (OS-CMS) was performed with octenylsuccinic anhydride by assistance of microwave and ultrasound irradiation using the dimethyl sulphoxicle/p-toluenesulphonic acid system and DMSO as solvents for activation of CMS as well as reaction medium of the following esterification. The prepared OS-CMS derivatives were characterized with regard to their structural, surface-active and performance properties. The application of both microwave and ultrasound irradiation as energy sources permitted to shorten the esterification time to several minutes from 24 h of the previously reported conventional heating [33], whereby the reaction efficiencies were high and the water-soluble derivatives exhibited excellent emulsifying efficiency as well as surfactant performance properties tested by washing power and antiredeposition efficiency. The results indicate also the high potential of both microwave and ultrasound energy sources to innovate and increase the efficiency of technological polysaccharide esterification processes.