Po
Polyisobutene
PolyisobuteneBarrier
A synthetic emollient and film-former that adds gloss and a flexible, water-resistant feel, often in lip products and long-wear formulas.
What it does
Polyisobutene is a synthetic polymer used as an emollient and film-former. It gives shine, a cushiony feel, and a flexible water-resistant film, which is why it shows up in glosses, long-wear textures, and some sunscreens. It works on feel and wear rather than acting on the skin.
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