Polystyrene
What is Polystyrene?
Polystyrene is a synthetic thermoplastic polymer created by polymerizing styrene monomers from petroleum sources. In cosmetics, it exists as microspheres or film-forming resins, primarily in makeup, sunscreens, and hair products. It works by depositing a thin, flexible layer on skin or hair, boosting water resistance, adhesion, and longevity while preventing smudging or fading. As a viscosity controller, it modifies flow and thickness, aiding even distribution, suspension of other ingredients, and overall product stability. Its opacity adds visual effects like pearlescence. Large particle size ensures it stays on the surface without penetrating the skin barrier, making it suitable for diverse formulations needing enhanced performance and sensory qualities.
Roles in Formulation
This ingredient serves the following purposes in cosmetic formulations:
Benefits
Creates durable films for better water and transfer resistance in makeup and sunscreens.
Adjusts product thickness for smoother application and improved stability.
Provides a non-comedogenic, smooth feel without pore clogging.
Who It's For
A quick guide for who this ingredient may suit (and who should be cautious).
| Who May Benefit | Who Should Avoid |
|---|---|
| Users of long-wear foundations and mascaras for extended hold. | Those preferring entirely natural or botanical ingredients. |
| People applying sunscreens or styling products needing water resistance. | People concerned about environmental microplastic accumulation. |
| Individuals seeking stable textures in creams and lotions. | Individuals with rare sensitivities to synthetic polymers. |
Safety Notes
- Low hazard potential with minimal skin irritation in safety assessments.
- Non-comedogenic, reducing risk of pore blockage.
Frequently Asked Questions about Polystyrene
What does polystyrene do in skincare products?
It forms protective films for wear resistance and controls viscosity for better texture and stability.
Is polystyrene irritating to skin?
It has low irritation potential based on cosmetic safety evaluations.
Does polystyrene clog pores?
No, it carries a comedogenic rating of zero.