Sodium acrylates copolymer is the sodium salt of a polymer comprised of acrylic acid, methacrylic acid or one of their simple esters. In cosmetics and personal care products, sodium acrylates copolymer functions as a binder, film former, opacifying agent, and viscosity increasing agent.
A binder is an ingredient that binds together other ingredients in a formulation. For example, binders are often used in pressed powders to keep them together in the container. As a film former, sodium acrylates copolymer leaves a thin, pliable film on the surface of skin or hair after application. The film has strong hydrophilic properties and provides a smooth feeling to the skin/hair. Sodium acrylates copolymer also functions as an opacifying agent, which means it can be added to clear or transparent cosmetic formulations to render them more resistant to visible light. Lastly, sodium acrylates copolymer functions as a viscosity increasing agent. The term viscosity corresponds to the concept of “thickness”, for example, honey has a higher viscosity than water. Therefore, as a viscosity increasing agent, sodium acrylates copolymer works to thicken formulations in order to make a product less runny and easier to spread.