Lauryl Methacrylate/Sodium Methacrylate Crosspolymer

Lauryl Methacrylate/Sodium Methacrylate Crosspolymer is a synthetic polymer—a long-chain molecule made up of smaller units linked together. It is not derived from natural sources but is manufactured through chemical synthesis for use in cosmetic formulations.In skincare products, this ingredient functions as a film former. This means it applies to the skin surface and dries to create a thin, continuous layer. This layer can help to temporarily smooth the appearance of the skin and may provide some water-retention benefits by reducing transepidermal water loss (TEWL).

When applied to the skin, the polymer particles disperse in the product's liquid base. As the water or volatile components evaporate, the polymer chains bind together and form a cohesive film across the skin surface. This creates a light seal that can temporarily lock in moisture and create a smoother, more uniform appearance.The crosslinked structure—where polymer chains are chemically linked at multiple points—makes the film more durable and less likely to crack or flake compared to non-crosslinked alternatives.

This ingredient is typically incorporated into formulations by manufacturers rather than used as a standalone treatment. Look for it in primers, lightweight moisturisers, or serums where film-forming properties are desired. Apply to clean, dry skin and allow a few moments for the film to set before applying other products. It is generally well-tolerated but may feel slightly occlusive if layered heavily, so start with a modest amount.

This ingredient is generally well-tolerated and recognised as safe in cosmetic use. Individuals with sensitive skin or polymer sensitivities should patch test first, though reactions are uncommon.