Anionic Organosilicones: Complexing Agents for Quaternary Compounds

It is well known that anionic thickeners such as carbomer and related polymers are generally incompatible with cationic ingredients. Combining carbomers with quaternary compounds or other cationic ingredients often leads to viscosity instability and high turbidity. In addition, the carbomer and quat can strongly interact resulting in the precipitation of a white, gummy mass. This has limited the formulators’ options for novel rheological properties in rinse-out conditioners. It has also restricted the choice of rheology modifiers that can be used when creating gel-based styling products that contain quaternary conditioning agents, resulting in products with less than optimal aesthetic properties. However, when quats are first complexed with anionic functional organosilicones, they can be successfully combined with carbomers and related polymers.

Because complexation with an anionic silicone apparently shields the cationic material from the anionic polymer, one might expect interference with the ability of the cationic material to deposit on anionic hair. Such interference would negatively affect conditioning properties such as wet comb-through, which is generally improved by the addition of low molecular weight (MW) quats. Complexing low molecular weight quats with anionic silicone does not, however, reduce the deposition of the quat onto hair. In fact, it can actually serve to increase the deposition of silicone onto hair, thereby improving conditioning properties.

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