辛基三甲基溴化铵与辛基硫酸钠混合水溶液的相行为

对辛基三甲基溴化铵(OTAB)与辛基硫酸钠(SOS)正、负离子混合表面活性剂水溶液的相行为进行了研究.在高浓度的溶液中,混合表面活性剂形成液晶相,随着混合摩尔比OTAB/SOS接近于1,液晶结构由六角相转层状相,同时夹杂少量沉淀物;在中等浓度时,任意混合摩尔比例下皆为均相透明溶液;在低浓度下,在很宽的OTAB/SOS混合摩尔比的范围,出现双水相,其中的表面活性剂稀薄相,为不同大小的胶团与囊泡组成的稀溶液,另一表面活性剂富集相中则为数密度很大的囊泡聚集体,富集相对油溶性染料的增溶作用比非富集相高得多.

Phase Behavior of Mixed Aqueous Solution of Octyltrimethylamonium Bromide and Sodium Octyl Sulfate

The phase behavior of aqueous mixture of octyltrimethylamonium bromide (OTAB) and sodium octyl sulfate (SOS) was studied. In concentrated solution, a liquid crystal phase formed and converted form hexangonal structure to lamellar when the molar ratio of OTAB/SOS approached to 1. The mixed surfactant solution is a homogeneous and transparent liquid in middle concentration range. When the concentration is low, aqueous two phase system appears in a wide range of OTAB/SOS molar ratio. In the aqueous surfactant two phase system , both vesicles and micelles exist in the surfactant-poor phase, while concentrated vesicle aggregates were contained in the surfactant-rich phase. Solubilization amount of oil-soluble dye in the surfactant-rich phase is much higher than that in the surfactant-poor phase.