Study on the properties of sodium lauroyl lactate anionic surfactant and cationic surfactant in a mixed system

The surface properties and applications of mixtures of an anionic surfactant (sodium lauroyl lactate (SLL)) and cationic surfactant (gemini quaternary ammonium salt with a hydroxyl group (GC12)) were investigated. The results showed that SLL/GC12 surfactant mixtures have synergistic effects, yielding higher surface activity and greater application performance. When the mole fraction of SLL (αSLL) was 0.4, the surface tension reached its minimum value. Furthermore, based on the calculated interaction parameters, stronger attractive interactions between the mixed SLL/GC12 surfactant molecules could be obtained at air/solution interfaces or with mixed micelles. When the mass fraction of SLL was 50%, its wetting ability and emulsifying capacity were optimal. The foam stability exceeded 95% when the mass fractions of SLL (WSLL) were 20%, 40%, and 50%. In addition, when the mole fraction of SLL was approximately 0.5, vesicles formed easily at a total solution concentration of 3 mM.