A series of symmetrical dialkyl methanesulfonate amphiphiles [DiC_nCHSO₃]_mM (n = 6, 7, 8) with different counter cations (M^m+ = H⁺, Li⁺, Na⁺, K⁺, Cu²⁺, Zn²⁺, Mg²⁺, Ca²⁺, Sc³⁺) were synthesized in five steps. Their solubility and critical micelle concentration (CMC) in water were determined highlighting a huge effect of the chain length and the nature of the cation. The hydrophilic–lipophilic balance of the surfactants were assessed with the phase inversion temperature (PIT)-slope method based on the deviation from the PIT of the reference C₁₀E₄/n-octane/0.01 M NaCl_(aq) emulsion through addition of increasing amounts of the dialkyl methanesulfonates. The hydrophilicity of the surfactants was thus ranked in terms of dPIT/dx_sulfonate. A “cation” scan with the [DiC₆CHSO₃]_mM/benzene/water systems at f_w = 0.5 was finally performed confirming the hydrophilicity ranking obtained with the PIT-slope method. It revealed that the [DiC₆CHSO₃]₂Mg behaves as a “Balanced Surfactant” able to form spontaneously a three-phase microemulsion system (Winsor III) just in the presence of water and oil, in the same way as the catalytic surfactant dimethyldioctylammonium molybdate, which has the same PIT-slope.

中文翻译：

---

阳离子对双尾甲烷磺酸盐两亲物二元和三元相行为的影响

一系列 具有不同抗衡阳离子（M ^{m +}  = H ⁺，Li ⁺，Na ⁺，K ⁺，Cu ^{2 +}，Zn ²的对称的甲烷磺酸二烷基二烷基酯两亲物[DiC _n CHSO ₃ ] _m M（n = 6，7，8）⁺，Mg 2 ⁺，Ca 2 ⁺，Sc ³⁺）分五个步骤合成。确定了它们在水中的溶解度和临界胶束浓度（CMC），突出了链长和阳离子性质的巨大影响。表面活性剂的亲水-亲脂平衡是通过相转化温度（PIT）-斜率法，通过添加参比C ₁₀ E ₄ /正辛烷/0.01 M NaCl _（aq）乳液与PIT的偏差来评估的。数量增加的甲磺酸二烷基酯。因此，以dPIT / dx_磺酸盐对表面活性剂的亲水性进行排名。用[DiC ₆ CHSO ₃ ] _m M进行的“阳离子”扫描 最终在f _w = 0.5的条件下，用/苯/水体系进行了测定，确认了用PIT斜率法获得的亲水性等级。结果表明，[DiC ₆ CHSO ₃ ] ₂ Mg表现为“平衡表面活性剂”，仅在水和油存在下，就可以与催化表面活性剂相同地自发形成三相微乳液体系（Winsor III）。钼酸二甲基二辛基铵盐，具有相同的PIT斜率。