Po
Polyisobutene
PolyisobuteneBarrier
A synthetic polymer that softens and leaves a flexible, water-resistant film — the shine in glosses and long-wear formulas.
What it does
A synthetic polymer that softens skin and leaves a flexible, water-resistant film. It adds shine and a cushiony feel, which is why it’s in glosses, long-wear products and some sunscreens. It works on feel and wear, not on skin.
Also known as
polyisobutylene
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