Determination of Liquid Paraffin Emulsions’ Stability Parameters Using Spans as Emulgent

Aims: To prepare liquid paraffin emulsions using spans of different grades as emulgent in extensively different concentrations and then determine the formulations’ stability parameters.

Study Design: The study consulted some literatures to have the basic knowledge before laboratory experiments were conducted.

Place and Duration of Study: This study was conducted in Obafemi Awolowo University Ile Ife, Nigeria laboratory between 2023 and 2024.

Methodology: The characteristic properties of different formulations of liquid paraffin emulsions prepared using spans of different grades as emulgent has been studied. The influence of emulgent of various concentrations (2.5- 30%) on the properties of w/o emulsions containing 30% aqueous phase was examined using dilution, dye-solubility, cobalt chloride tests and Rion viscotester VT-04 to determine melting point and softening determination, creaming profile, viscometric and emulsion type.

Results: The result revealed Span 20 and Span 80 to be light yellowish in colour and hydrophobic in nature while Span 60 was miscible with water when heated to 75 oC. Liquid paraffin emulsions formulated via Spans 20, 80 and 85 were all noticed to be physically stable liquid emulsion products at room temperature. The values of the softening and melting point of the Span 85 based creams were lower (32-33 and 35-36 oC) than those of Span 80 based products (35-36 and 41-43 oC) respectively. The yield values of Spans 20 and Span 80 solid emulsions were observed to be relatively high in the range 3500-4000 P when compared with those of Span 85 based creams having 500-1050 P. Two layers of different densities of the dispersed phase were observed by the emulsion phase. Rapid dispersion of the Spans 20, 80 and 85 stabilized samples 1, 2 and 3 emulsion drops that were placed into distilled water was observed. The other Span based formulations which contain higher concentrations (15-30%) of the emulgent (samples 4, 5, 6 and 7) were also observed to be miscible with water.

Conclusion: In conclusion, the emulgent at various concentrations has positive influence on liquid paraffin emulsions at some friendly conditions.