Highly viscous hydrophobic isosorbide biobased polyester O/W emulsions are prepared through catastrophic phase inversion. The process is followed in situ with two different methods: torque and light backscattering (LBS). Considering high viscosity of the system, only discontinuous conductivity monitoring is performed for comparison.
View Article and Find Full Text PDFThe Phase Inversion Temperature of a reference C10E4/n-Octane/Water system exhibits a quasi-linear variation versus the mole fraction of a second surfactant S2 added in the mixture. This variation was recently proposed as a classification tool to quantify the Hydrophilic-Lipophilic Balance (HLB) of commercial surfactants. The feasibility of the so-called PIT-slope method for a wide range of well-defined non-ionic and ionic surfactants is investigated.
View Article and Find Full Text PDFThe phase behavior of well-defined C10E4/ester oil/water systems versus temperature was investigated. Fifteen ester oils were studied and their Equivalent Alkane Carbon Numbers (EACNs) were determined from the so-called fish-tail temperature T* of the fish diagrams obtained with an equal weight amount of oil and water (f(w)=0.5).
View Article and Find Full Text PDFThe equilibrium phase behavior of the well-defined system tetraethyleneglycol decyl ether (C(10)E(4))/n-octane/water (SOW) at variable temperature (T) was revisited by careful analysis of the three bidimensional cuts, namely, the gamma (at constant water-oil ratio), chi (at constant surfactant concentration), and Delta (at constant temperature) plots. A straightforward methodology is reported to determine the frontiers of the triphasic (Winsor III) domain on any cut of the SOW-T phase prism. It comes from the systematic analysis of another cut, here gamma at different water-oil ratios and chi at different surfactant concentrations from the knowledge of Delta cuts at different temperatures.
View Article and Find Full Text PDFMany phenomena take place during different types of emulsion inversions, particularly a change in interface curvature and drop size, which could be detected by backward light scattering. Monitoring the backscattering signal allows us to detect the emulsion inversion in three main cases, one transitional and two catastrophic types. The backscattering data could give some clue as to emulsion morphology, which is not available from conductivity measurements.
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