Preparation and Characterization of Polymeric Surfactants Based on Epoxidized Soybean Oil Grafted Hydroxyethyl Cellulose

Epoxidized soybean oil (ESO) grafted hydroxyethyl cellulose (HEC) was prepared via ring-opening polymerization, in which the hydroxyl groups of HEC acted as initiators and the polymeric ESO were covalently bonded to the HEC. Hydrolysis of ESO-grafted HEC (ESO-HEC) was performed with sodium hydroxide, and the hydrolyzed ESO-HEC (H-ESO-HEC) products were characterized via Fourier transform infrared (FT-IR) and H-1 and C-13 nuclear magnetic resonance (NMR) spectroscopies, high-temperature gel permeation chromatography (HT-GPC), and differential scanning calorimetry (DSC). The results indicated that ring-opening polymerization of ESO occurred with the hydroxyl groups of HEC as initiators. The molecular weights of the H-ESO-HEC products were varied by adjusting the mass ratio of HEC and ESO. Through neutralizing the carboxylic acid of H-ESO-HEC with sodium hydroxide, novel polymeric surfactants (H-ESO-HEC-Na) were obtained, and the effects of polymeric surfactants on the surface tension of water were investigated as a function of concentration of H-ESO-HEC-Na. The H-ESO-HEC-Na was effective at lowering the surface tension of water to 26.33 mN/m, and the critical micelle concentration (CMC) value decreased from 1.053 to 0.157 g/L with increases in molecular weights of the polymeric surfactants. Rheological measurements indicated that the H-ESO-HEC-Na solutions changed from pseudoplastic property to Newtonian with increasing shear rate.