Polyacrylate-21

Polyacrylate-21 is a synthetic polymer—a long-chain molecule made up of repeating units—commonly used in cosmetic formulations. It functions as a film-forming agent, meaning it dries to create a thin, flexible layer on the skin or hair.In skincare products, polyacrylate-21 is primarily used for its binding and film-forming properties. It helps other ingredients adhere to the skin and can provide a light, breathable protective barrier that sits on the surface rather than penetrating deeply into the skin.

Polyacrylate-21 works through film formation. When applied to the skin, the polymer dries to create a lightweight, flexible coating that adheres to the outer layers of the skin. This film acts as a physical barrier, helping to reduce transepidermal water loss and protect against external irritants.The film is designed to be breathable, so it doesn't occlude the skin entirely. Instead, it provides a protective layer that can help lock in moisture while remaining flexible enough to move with facial expressions and skin movements.

Polyacrylate-21 is typically a supporting ingredient rather than a star active, so its benefits are realised best as part of a complete formulation. Apply products containing this ingredient to clean, dry skin. If using it in a serum or lightweight moisturiser, allow a few seconds for the film to form before applying subsequent layers. There is no need to adjust frequency based on this ingredient alone.

Polyacrylate-21 is generally well-tolerated and has a long safety history in cosmetics. It is unlikely to cause irritation, though individuals with very sensitive skin should patch-test first, as with any new product.