Dehydroabietyl Glycidyl Ether Grafted Hydroxyethyl Chitosan: Synthesis, Characterization and Physicochemical Properties

A series of novel polymeric nonionic surfactants based on water-soluble N,O-hydroxyethyl chitosan (N,O-HECTS) and dehydroabietyl glycidyl ether (DAGE), DAGE-g-N,O-HECTSs, were synthesized by an additive reaction between N,O-HECTS and DAGE. The structures of DAGE-g-N,O-HECTSs were characterized by FT-IR and H-1 NMR. The substitution degree of hydroxyethylation (DSHE) of N,O-HECTS and the grafting degree (DG) of DAGE onto N,O-HECTS for DAGE-g-N,O-HECTSs were determined by elemental analysis. The surface activities of DAGE-g-N,O-HECTSs in aqueous solution were investigated by measuring the surface tension. The experimental results showed that the degree of grafting (DG) of DAGE-gN,O-HECTSs could have a significant impact on their critical micelle concentrations (CMCs) and surface tensions at the CMC (gamma(CMC)), but the DG of DAGE-g-N,O-HECTSs had almost no effect on the minimum of surface tensions (gamma(min)) When using the DAGE-g-N,O-HECTSs as emulsifier, the increase in DG had a favorable influence on the stability of an emulsion of water and benzene. At a DG greater than 40.45%, the emulsifying power of DAGE-g-N,O-HECTS exceeded that of Tween-60.