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POLYISOBUTENE

Description

Polyisobutene is a synthetic oil-like substance widely used in cosmetic and skincare formulations. This versatile ingredient is derived from isobutylene, a byproduct of petroleum refining. Its molecular structure consists of repeating isobutylene units, resulting in a clear, colorless, and odorless fluid with a range of viscosities depending on its molecular weight.

In skincare products, polyisobutene functions primarily as an emollient and thickening agent. It forms a protective barrier on the skin's surface, helping to reduce transepidermal water loss and maintain hydration. This occlusive property makes it particularly beneficial in lip care products and moisturizers designed for dry skin.

Polyisobutene also enhances the texture and spreadability of formulations, contributing to a smooth, silky feel upon application. Its stability and resistance to oxidation make it an excellent choice for extending the shelf life of cosmetic products. Additionally, polyisobutene can act as a solvent for other ingredients, improving their dispersion within formulations.

While generally considered safe for topical use, individuals with sensitive skin should patch test products containing polyisobutene to ensure compatibility. Its non-comedogenic nature makes it suitable for various skin types, including acne-prone skin.