Hydrogenated Styrene/Isoprene Copolymer

What is Hydrogenated Styrene/Isoprene Copolymer?

Hydrogenated Styrene/Isoprene Copolymer is a synthetic polymer produced by copolymerizing styrene and isoprene monomers, then hydrogenating to saturate bonds for greater stability and reduced reactivity. Primarily used in color cosmetics like lipsticks, mascaras, and eyeliners, as well as hair care products, it serves as a viscosity controlling and film-forming agent. In formulations, it increases thickness, especially in oil phases, aiding pigment suspension, enhancing spreadability, and creating a flexible film that improves wear time and adhesion without stickiness. This makes it ideal for anhydrous systems where it prevents settling and supports consistent texture during application and use.

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:

Viscosity controlling agent
Adjusts thickness to the desired level for stability and usability, improving dispensing, suspension, and texture across many formulation types.

Benefits

Improves product thickness for better dispensing and even application.

Enhances formulation stability by suspending particles effectively.

Provides a smooth, non-tacky feel with film-forming properties for longer wear.

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 makeup seeking stable, smooth textures.
Those with rare allergies to styrene-derived polymers.
Individuals with oily or acne-prone skin due to non-comedogenic nature.
Individuals preferring fully natural or botanical ingredients.
People applying oil-based products like lip colors or mascaras.
People sensitive to synthetic film-formers, though uncommon.

Safety Notes

  • Considered low hazard in cosmetic use by safety assessments.
  • Non-comedogenic, unlikely to clog pores.

Frequently Asked Questions about Hydrogenated Styrene/Isoprene Copolymer

What is Hydrogenated Styrene/Isoprene Copolymer used for?

It controls viscosity and forms films in makeup and hair products for better texture and wear.

Is it safe for sensitive skin?

Rated low hazard with no notable irritation concerns in cosmetic applications.

Does it clog pores?

Has a comedogenic rating of 0, suitable for acne-prone skin.