Ingredient · Updated
Polyisobutene
Found in 2 products
What is Polyisobutene?
Polyisobutene is a synthetic polymer made by polymerizing isobutene, a simple hydrocarbon. It is a type of rubber often used for its adhesive and viscosity-enhancing properties.
In cosmetics, polyisobutene is commonly included to improve the texture and staying power of lip care products and makeup. It creates a smooth, glossy finish and helps products adhere better to the skin. While the ingredient is generally considered safe for topical use, there is limited research on its long-term health effects.
When you see polyisobutene on a label, it is generally for its function as a texture enhancer or adhesive agent in cosmetics, rather than for any nutritional or health-related purpose.
Commonly found in: Lip Care, Makeup, Skin Care, Hair Styling Products
Polyisobutene is generally recognized as safe for use in cosmetics and personal care products in the U.S.
Current research indicates that polyisobutene is safe for topical application in consumer products, but comprehensive studies on long-term effects are limited.
Polyisobutene is a synthetic ingredient and does not involve animal products, making it generally acceptable for vegan use.
Sources: Safety Assessment of Polyisobutene as Used in Cosmetics
Scout's take
Polyisobutene is a synthetic polymer used as a binder and film-forming agent in lip balms. While it is safe for topical application, it is not intended for ingestion and may cause irritation in sensitive individuals.
More from Scout's analyses
Standard formulation ingredient — neither beneficial nor harmful at typical use.
from the analysis of Clinique High Impact Waterproof MascaraAll 2 products with Polyisobutene
Where Polyisobutene shows up
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