Synergistic effect of binary mixtures contained newly cationic surfactant: Interaction, aggregation behaviors and application properties

The synergistic effect in mixed different mole ratio of cationic with anionic, nonionic and zwitterionic surfactant binary systems are investigated, respectively, by surface tension, FTIR, DLS and TEM measurements. Besides the application properties of wetting, emulsification, foamability in binary systems of anionic or nonionic with addition of 1% or 3% cationic surfactant are also performed. Molecular interactions are characterized by the synergistic parameters βm and the deviation between the ideal system and experimental results are also discussed. It shows the synergistic effects (evaluated by βm) of investigated four systems has follow orders: cationic/anionic > cationic/nonionic (without ethoxylate unit) ≈ cationic/zwitterionic > cationic/nonionic (with ethoxylate unit). The aggregates size in cationic/anionic systems demonstrate cationic-rich mixtures easier forming large aggregates, but not vesicles observed in all investigated mole ratios. The wetting angle increased for anionic or nonionic surfactant with addition of 1% or 3% (weight percentage) C16NC1. Emulsification ability of mixed anionic enhanced but nonionic slightly decreased with addition of small amount of C16NC1. And the foam volume decreased for anionic/cationic systems, oppositely, an increasing in foam high for mixture of cationic/nonionic surfactant.