C(下标 n)NCl和SDS在水溶液中的相互作用

The interaction between sodium dodecyl sulfate (SDS) and 3-alkoxyl-2-hydroxypropyl trimethyl ammonium chloride (C(subscript n)NCl) in aqueous systems was investigated by means of microcalorimetric titration. The pseudo-critical micellar concentration (pcmc) and thermodynamic parameters for the formation of the micelle of each mixture surfactant system were estimated from the calorimetric data and the titration curve. The formation enthalpy and entropy of the mixture micelle are discussed based on the structure of the surfactant using the iceberg model. The results show that the interaction between the hydrophobic chains of the SDS and the C(subscript n)NCl is more important than the mutual electrostatic attraction between the negatively charged end group of SDS and the positively charged end of C(subscript n)NCl in the synergistic interaction between the anionic and cationic surfactants.