A high-performance silicone-grafted film former designed to provide exceptional water and sebum resistance. This polymer creates a flexible, breathable shield on the skin, significantly extending the wear time of color cosmetics and sunscreens.
- INCI Name:
- Acrylates/Polytrimethylsiloxymethacrylate Copolymer
- Chemical/Scientific Name:
- Copolymer of acrylic acid, methacrylic acid, or one of their simple esters and a silicone macromer.
- Common Aliases:
- Silicone-acrylate copolymer, Film-forming silicone polymer.
| Category: | Texture Enhancers |
| Source Origin: | Synthetic |
| Comedogenic Rating: | 0 |
| Primary Industries: | Color Cosmetics, Sun Care, Hair Care |
| Solubility: | Oil-soluble (dispersible in volatile silicones or hydrocarbons) |
At a Glance: Properties & Effects
| Formula Stability: | |
| Texture Enhancement: | |
| Irritation Risk: |
Primary Benefits:
- Provides superior water resistance and “rub-off” resistance in foundations and lipsticks.
- Enhances the stability of UV filters by keeping them uniformly distributed on the skin surface.
- Offers a non-tacky, silky skin feel compared to traditional organic film formers.
- Maintains a breathable barrier that allows for moisture vapor transmission.
Potential Risks:
- Requires specialized oil-based cleansers or micellar waters for efficient removal.
- Potential for formulation instability if not properly solubilized in compatible carriers.
Biological Action & Cosmetic Profile
The molecular architecture of this copolymer consists of a robust acrylate backbone with grafted silicone side chains. While the acrylate portion ensures strong adhesion to the skin or hair, the polytrimethylsiloxymethacrylate segments provide the characteristic slip and flexibility associated with silicones. This dual nature prevents the film from becoming brittle or cracking during facial movements, a common flaw in older, purely organic film-forming agents.Synthetic hybrid polymers like this one function by forming a continuous, hydrophobic lattice upon the evaporation of volatile carriers such as Isododecane or Cyclopentasiloxane. This lattice effectively traps pigments and active ingredients against the stratum corneum. Because the film is semi-permeable, it does not interfere with normal skin respiration or thermoregulation, making it suitable for high-performance athletic sunscreens and “24-hour” makeup formulations.
Broader Applications & Origins
Sun protection products frequently employ this copolymer to achieve high SPF ratings that persist after swimming or sweating. By ensuring that UV filters do not migrate or pool in skin furrows, the polymer helps maintain a consistent protective layer. In hair care, the same film-forming mechanism provides humidity resistance and frizz control without the heavy, “plastic-like” buildup of traditional resins.Liquid lipsticks and mascaras rely on this technology to prevent smudging and transfer. The silicone component reduces the surface tension of the formula, allowing it to spread effortlessly across the skin or lashes before setting into a permanent, water-repellent finish. In some cases, it is combined with Silica or Dimethicone to modulate the final gloss or matte appearance of the product.
Routine Integration
Synergies:
- Volatile hydrocarbons like Isododecane facilitate rapid drying and even film distribution.
- Emollients such as Dimethicone improve the overall sensorial profile and flexibility of the film.
- Physical UV filters like titanium dioxide or zinc oxide exhibit improved suspension stability when used with this copolymer.
Conflicts:
- Purely water-based (Aqua) serums may not layer well over products containing high concentrations of this copolymer due to its strong hydrophobic nature.
Clinical Consensus & Safety
The Cosmetic Ingredient Review (CIR) Expert Panel has evaluated the safety of acrylate copolymers and silicone-grafted polymers, concluding they are safe for use in cosmetic products at current practice concentrations. Because of their high molecular weight, these polymers do not penetrate the skin barrier, significantly minimizing the risk of systemic toxicity or localized irritation. Clinical assessments typically show a low potential for sensitization, even in leave-on products designed for the sensitive eye area.
Is this ingredient considered a microplastic?
While it is a synthetic polymer, its classification varies by jurisdiction. In many regulatory frameworks, liquid or wax-like polymers that do not exist as solid particles in the final formulation are distinguished from solid microplastic beads.
Does it clog pores or cause acne?
No, this copolymer is considered non-comedogenic. Its breathable structure prevents the trapping of sebum in a way that would typically lead to comedone formation, though thorough cleansing is always recommended for long-wear products.
How do I remove products containing this ingredient?
Due to its high resistance to Aqua and sweat, an oil-based cleanser, cleansing balm, or a biphasic makeup remover is required to break down the polymer film effectively.