Choosing Sustainable Alternatives for Cosmetic Emollients: Sustainability vs Rheological Performance

Abstract

Understanding the physicochemical properties of sustainable raw materials plays a crucial role in the formulation process, since it allows to predict formulation issues normally interlinked with this type of compounds. The main goal of this work was to design specific tools to forecast the spreadability of sustainable raw materials. To meet this goal, 5 alternatives for petrolatum (P) and 5 alternatives for dimethicone (D) were selected. The experiments included in vitro and in vivo spreading behavior characterization and viscosity measurements. For P alternatives, the spreading value was best fitted as a function of the logarithm of viscosity and for D alternatives the spreading value was best fitted as a direct function of viscosity. The mathematical model defined for P alternatives could be used for the most diverse chemical and physical types of alternatives, which include butter-like, jelly-like and wax-like raw materials; the mathematical model defined for D could be used for high, medium and low viscosity raw materials. In conclusion, the application of these tools will help the entire replacement process and will also contribute to the development of sustainable cosmetic products with higher performance.