What it is
Acrylamide/DMAPA Acrylates/Methoxy PEG Methacrylate Copolymer is a synthetic copolymer built from four monomer types: acrylamide, dimethylaminopropylacrylamide (DMAPA), methoxy polyethylene glycol methacrylate, and one or more acrylic acid esters. The combination of ionic DMAPA units and hydrophilic PEG side chains gives the polymer both substantivity to hair and skin and good water dispersibility. In formulation it functions primarily as a film former, depositing a flexible, continuous layer that provides hold and conditioning. It appears notably in gel and milk sunscreen formats where it contributes to the lightweight, non-sticky texture characteristic of Japanese UV products. Toxicological data are limited; no GHS hazard classifications have been assigned for the polymer, and the acrylamide monomer content is controlled to trace levels in finished grades.
Safety & warnings
Residual free acrylamide monomer is a known neurotoxin and probable human carcinogen; cosmetic-grade polymers are manufactured to minimize residuals. No specific allergen or sensitization concerns are documented for the cured polymer itself. Individuals with known sensitivity to acrylic polymers should patch-test products containing this ingredient. No comedogenicity data are available. The polymer is not for ingestion or flavor use.
Origin & sourcing
Fully synthetic; produced by free-radical polymerization of acrylamide, DMAPA (3-dimethylaminopropylamine-derived monomer), methoxy PEG methacrylate macromonomer, and acrylic acid or short-chain acrylate esters. The polymerization is typically carried out in aqueous solution or solvent and the product is isolated as a powder or concentrated dispersion.
History
INCI nomenclature for this copolymer class was established by the Personal Care Products Council and is listed in EU CosIng under the functions film forming and hair fixing. It appears in multiple cosmetic-shaping patents from the 2000s onward, reflecting growing interest in PEG-modified film formers that balance hold strength with washability.
Questions everyone asks
What does this ingredient do in a sunscreen formula?
It acts as a film former, helping the product spread smoothly and adhere to skin, which can improve the lightweight, gel-like texture of sunscreen without contributing to UV protection.
Is this ingredient safe for sensitive skin?
The cured copolymer has no documented sensitization concern in available safety databases; however, residual acrylamide monomer in lower-grade polymers can be an irritant, so it is used at controlled purity levels in cosmetics.
Why does this ingredient appear primarily in Japanese sunscreens?
Japanese brands such as Anessa and Shiseido have pioneered lightweight aqueous-gel UV formats, and this PEG-containing film former is well-suited to the low-residue, comfortable feel those products target.
Is it water-soluble?
The methoxy PEG side chains make the polymer water-dispersible, allowing it to be incorporated into aqueous gel and milk formulations and rinsed off with water.