TITLE:
Temperature Dependent Phase Behavior of Pseudo-Ternary Thiourea X-100 Surfactant +1-Hexanol/Oil/Water Systems
AUTHORS:
Mohd Zul Helmi Rozaini
KEYWORDS:
Surfactant; Amphiphile; Co-Surfactant; Microemulsion; Micelles; Reverse Micelles; Phase Behavior; Phase Diagram; Thiourea X-100; 1-Hexanol
JOURNAL NAME:
Open Journal of Physical Chemistry,
Vol.2 No.3,
August
31,
2012
ABSTRACT: Temperature dependent phase behavior of Pseudo-ternary Thiourea X-100 + 1-hexanol (1:5 molar ratios)/oil/water systems is reported. The influence of nature of hydrocarbon oil and type of electrolytes (weak as well as strong) has been investigated on the temperature induced phase behavior of the ternary system. At surfactant concentration, Φs = 40%, a “nose shaped” microemulsion region is observed. Below one-phase microemulsion region, Lα phase appears. The presence of NaCl decreases the domain size of 1Φ micellar region whereas oxalic acid first decreases the domain below Φw 18 in the lower boundry of the phase diagram. The critical weight fraction of water, Φwcri decreases in presence of both electrolytes. However, Φwmax increases in presence of oxalic acid and remains constant in presence of NaCl as compared to salt free system. Furthermore, when cyclohexane was replaced by a longer straight chain hydrocarbon, dodecane, the domain of the one-phase microemulsion region is tremendously increased.