Using a Brookfield RV viscosity meter with a SC4-29 mixer, we determined the rheological behavior of the two emulsions. In the graph A-1, the path of the viscosity curve from the cutting force against the shear rate velocity are indicated. The results from the emulsion maintained at a constant 25°C were recorded at 1 minute intervals and each Share rate was maintained constant for 1 minute before checking.

   Hydrogenated Poly-1 Decene 5.0
   Cetyl Palmitate 4.0
   Glyceryl Stearate 2.0
   Octyl Palmitate 1.0
   Aqua 79.5
   SESAMULS® OW 4.5
   Diglycerin 4.0

The different path of the viscosity curve, obtained by continually increasing and decreasing the rotation speed of the viscosimeter, hypothesizes the presence of different internal structures inside the two emulsions.

With the intention of highlighting eventual theoretical changes that may eventually occur some time after the preparation, we determine the flow curve of the two emulsions 1 month after preparation. With the results obtained we created the graphs A-2 and A-3, where the viscosity curves recorded at preparation (after 48 hours) and after 30 days of ageing are shown. Let’s start with the emulsion obtained through LEE processing.

Comparing previously obtained results, we can see that after a month there is little difference in viscosity. Even its appearance, and above all the shiny effect that characterizes this type of emulsion, remain unvaried.
Contrarily, the emulsion prepared with the traditional hot emulsion method behaved differently and lost its shiny appearance.