Alkyl dimethicone as modifiers of oils

Surface active materials are important because they alter surface tension, which is a required first step in providing wetting, spreading, emulsification, detergency and cosmetic aesthetics. The use of surfactants in aqueous formulation is the best known example of surfactant usage. The less appreciated use of surfactants is the modification of oils to lower surface tension, resulting in improved spreading, wetting and gelation. The use of correctly selected amphiphilic silicone molecules allows one to replace traditional silicone compounds, including D5 and fluids, with natural oils, esters and other products having a greener profile. This process has been referred to as “greening with silicone”.

 The physical chemistry of most cosmetic formulations is so complex that a detailed analysis of what is happening at the surface during the use of the product would be enough for an advanced degree in chemistry. The reason for this is that formulations are a complex combination of ingredients including water, oil, surfactants, antimicrobial agents, salt and many other components. All formulations include modifiers of surface tension, a necessary prerequisite to wetting, emulsification, foaming, and detergency. The interaction of all the various components is the controlling property for the formulation, not the performance of the various components alone or neat in solvent. We have addressed the interaction between (a) anionic and cationic surfactants,1 (b) anionic and amphoteric surfactants,2 and (c) anionic and cationic gemini surfactants;3 all of which are aqueous systems. This article will address oil based systems and synergistic interactions between alkyl silicones and oils.

Amphiphilic materials