Phase behavior, formation, and rheology of cubic phase and related gel emulsion in Tween 80/water/oil systems.

We investigated the phase behavior, formation, and rheology of the cubic phase (I(1)) and related O/I(1) gel emulsion in water/Tween 80/oil systems using squalane, liquid paraffin (LP), and decane as oil components. In the phase behavior study, the phase sequences were similar for squalane and LP systems, while a lamellar liquid crystal (L(alpha)) was observed for decane system. In all the systems the addition of oil to W(m) or H(1) phase induced the I(1) phase, which can solubilize some amounts of oil followed by the appearance of I(1)+O phase.

Wormlike micelles in Tween-80/CmEO3 mixed nonionic surfactant systems in aqueous media.

Formation and rheological behaviour of viscoelastic wormlike micellar solution in aqueous mixed system of nonionic surfactants, polyoxyethylene sorbitan monooleate (Tween-80) and trioxyethylene alkyl ether (C(m)EO(3), m=12, 14, and 16) was studied. The semi-dilute aqueous solution of Tween-80, in presence of C(m)EO(3) shows a sharp increase in viscosity leading to the formation of a gel-like highly viscoelastic solution reaching a maximum, but decreases beyond an intermediate concentration and finally phase separates. When C(12)EO(3) is replaced by C(14)EO(3) the micellar growth occurs more effectively.