当季铵盐表面活性剂在极性溶剂中具有合适溶解度时,它可使该极性溶剂与另一种非极性溶剂形成的混合溶剂自发分相,形成稳定的两相界面.借鉴表面活性剂双水相现象的概念,这种现象被称为表面活性剂非水双相(NSTP),也可简称为双油相.产生此种现象的原因被归结为季铵盐表面活性剂在极性溶剂中达到合适的溶解度时,从而逐出与之不亲合的非极性溶剂.
When a quaternary ammonium surfactant has a suitable solubility in a polar solvent, it can induce the phase self-separation of mutually soluble polar and apolar mixed solvents and a stable interface between the two phases can be formed. This phenomenon was attributed to the quaternary ammonium surfactant reaching suitable solubility in the polar solvent and driving out a considerable part of the apolar solvent, in which the surfactant is insoluble. As a result, phase separation appears. Using aqueous surfactant two-phase as reference, we suggest that it be termed as nonaqueous surfactant two-phase (NSTP) and also as two oil phases for short.