Synergism Between Glycoside-based Surfactants And Quaternary Ammonium Salts

Surfactant mixtures generally exhibit superior performances than individual surfactants due to the possibility of synergism. Glycoside-based surfactants have shown interesting applications in detergents, cosmetics, pesticides, and medicine because of their good dermatological compatibility and biodegradability. Quaternary ammonium salts have been widely used as antimicrobials, fabric softeners and antistatic agents due to their strong adsorbability and hydrophobicity. Glycoside-based surfactant/quaternary ammonium salt mixtures will combine the excellent properties of pure surfactants and play an important role in the development of multi-functional disinfection and washing products. Surface tension, foaming properties, wetting ability, emulsification and detergency have been taken into account to investigate the influence of multifunctional derivatization on the physicochemical properties of binary mixtures of glycoside-based surfactants in combination with quaternary ammonium salts. Effect of the multifunctional derivatization on the phase behavior of glycoside-based surfactant/quaternary ammonium salt/water ternary system has also been carried out. The three glycoside-based surfactants are nonionic decyl glycoside(APG), and the glycoside-based derivatives, nonionic dodecyl ethoxy glycoside(AEG) and anionic disodium dodecyl ethoxy glycoside citrate(AEG-EC). The two quaternary ammonium salts are didecyldimethylammonium chloride(DDAC) and dodecyldimethylbenzylammonium chloride(1227).(1) For APG/DDAC mixed systems, synergism was observed in surface tension, foaming and emulsifying properties, not in wetting ability and detergency. For APG/1227, synergism was observed in surface tension and emulsifying properties, not in foaming property, wetting ability and detergency.(2) For AEG/DDAC mixed systems, synergism was observed in foaming and emulsifying properties, not in wetting ability and detergency. For AEG/1227, synergism was observed in surface tension, foaming and emulsifying properties, while the wetting ability and detergency exhibited no such effect.(3) For AEG-EC/DDAC mixed systems, synergism was observed in surface tension, wetting ability and emulsifying property, not in foaming property. For AEG-EC/1227, synergism was observed in surface tension and wetting ability, while the foaming and emulsifying properties exhibited no such effect.(4) Glycoside-based surfactant/quaternary ammonium salt mixtures show the best performance when the mass concentration of glycoside-based surfactant is 80%. And the mixtures of glycoside-based surfactants in combination with DDAC are better than the mixtures with 1227.(5) For glycoside-based surfactant/DDAC mixed systems, the degree of synergism in the mixed monolayer formation increases in the order: AEG/DDAC < APG/DDAC < AEG-EC/DDAC, while the synergism in the mixed micelle obeys the following order: AEG/DDAC < AEG-EC/DDAC < APG/DDAC.(6) For glycoside-based surfactant/1227 mixed systems, interaction in the mixed monolayer formation becomes stronger in the order: AEG/1227 < AEG-EC/1227 < APG/1227. The degree of synergism in the mixed micelle follows the order: AEG-EC/1227 < AEG/1227 < APG/1227.(7) Phase diagrams of the APG/DDAC/H2 O, AEG/DDAC/H2 O and AEG-EC/DDAC /H2 O ternary systems are characterized by a micellar phase, a region where lamellar and micellar phases coexist and a lamellar phase. Compared with the APG/DDAC/H2 O and AEG/DDAC/H2 O, the phase diagram of AEG-EC/DDAC/H2 O contains a region of “Aqueous Surfactant Two-Phase”.(8) For APG/1227/H2 O and AEG/1227/H2 O ternary systems, the studied samples are all micelle solutions. The phase diagram of AEG-EC/1227/H2 O is characterized by a micellar phase and an “Aqueous Surfactant Two-Phase” region.