C_nNCl和SDS在水溶液中的相互作用

Interaction Between Sodium Dodecyl Sulfate and 3-Alkoxyl-2-hydroxypropyl Trimethyl Ammonium Chloride in Aqueous Systems

用滴定式微量量热法研究了阳离子表面活性剂-3-烷氧基-2-羟丙基三甲基氯化铵(CnNCl)和十二烷基硫酸钠(SDS)之间的相互作用。根据量热数据和滴定曲线计算出了混合表面活性剂体系的拟临界胶束浓度和混合胶束形成的热力学参数。依据表面活性剂的结构和冰山结构模型讨论了混合胶束的形成焓、形成熵及其变化趋势,解释了在阴阳离子表面活性剂之间的协同作用中,CnNCl和SDS疏水链之间的相互作用随CnNCl的链长改变而变化的趋势。

The interaction between sodium dodecyl sulfate(SDS) and 3-alkoxyl-2-hydroxypropyl trimethyl (ammonium) chloride(C_(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_(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_(n)NCl in the synergistic interaction between the anionic and cationic (surfactants).