Acrylates/Stearyl Methacrylate Copolymer

What is Acrylates/Stearyl Methacrylate Copolymer?

Acrylates/Stearyl Methacrylate Copolymer is a high-molecular-weight synthetic polymer derived from acrylic esters and stearyl methacrylate, featuring a long C18 alkyl chain for hydrophobicity. Primarily used in leave-on skincare products like moisturizers, sunscreens, and foundations, it functions by forming a flexible interfacial film around oil droplets in emulsions, preventing coalescence and separation for long-term stability. As a viscosity controller, it creates a three-dimensional network in formulations, adjusting thickness to enhance spreadability, suspension of actives, and overall sensory feel, often imparting a non-greasy, matte-like finish without residue.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1 View on EWG →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Emulsion stabilizer
Improves emulsion robustness by preventing droplet coalescence and phase separation, often by thickening, structuring, or strengthening the interfacial layer.
Viscosity controlling agent
Adjusts thickness to the desired level for stability and usability, improving dispensing, suspension, and texture across many formulation types.

Benefits

Stabilizes emulsions to maintain product consistency over time.

Controls viscosity for smoother application and better texture.

Supports non-comedogenic formulations suitable for daily use.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
Individuals seeking stable, long-lasting skincare products.
People with rare sensitivities to acrylate polymers.
Those preferring lightweight, non-greasy textures in moisturizers.
Those preferring entirely natural or plant-based ingredients.
Users of oil-in-water emulsions like lotions and creams.
Individuals experiencing irritation from synthetic thickeners.

Safety Notes

  • Rated low hazard by EWG with scores of 1 across categories.
  • Non-comedogenic with a rating of 0, unlikely to clog pores.

Frequently Asked Questions about Acrylates/Stearyl Methacrylate Copolymer

What does Acrylates/Stearyl Methacrylate Copolymer do in products?

It stabilizes emulsions and adjusts viscosity for better stability, texture, and application.

Is it safe for sensitive skin?

It has a low hazard rating and low irritation potential from authoritative reviews.

Does it clog pores?

No, it carries a comedogenic rating of 0, making it suitable for acne-prone skin.