Hyaluronic Acid/Polyisopropylacrylamide Copolymer

Hyaluronic Acid/Polyisopropylacrylamide Copolymer is a hybrid molecule that combines hyaluronic acid—a naturally occurring humectant found in skin—with a synthetic polymer called polyisopropylacrylamide. This modification alters how the ingredient behaves on the skin, potentially improving its stability and performance compared to unmodified hyaluronic acid.The copolymer functions as a humectant, meaning it draws moisture from the environment and deeper skin layers to the surface, helping to plump the epidermis and support skin hydration. It also conditions the skin by forming a lightweight…

As a humectant, the ingredient draws moisture (hygroscopic properties) into the stratum corneum—the outermost layer of skin. The polymer component may also help this process by forming a thin, permeable layer that retains moisture while allowing the skin to breathe. This dual action can contribute to improved hydration without occlusion.The modification to standard hyaluronic acid may theoretically improve stability in formulations and alter how the ingredient interacts with the skin's surface, though the extent of these benefits in real-world use remains variable.

This ingredient is typically found in serums, hydrating toners, and moisturisers. For best results, apply it to damp skin to maximise its humectant effect—the moisture it draws in will be more available if the skin is already slightly hydrated. It can be layered with other hydrating or active ingredients and works well in layered skincare routines. If using in a serum, follow with an appropriate moisturiser to seal in hydration, especially in dry climates.

Generally well-tolerated across most skin types. Rare sensitivities have been reported; patch test if you have sensitive skin or known allergies to hyaluronic acid or polymers.