Polyisobutene ek synthetic hydrocarbon polymer hai jo cosmetics mein emollient, thickener aur film-forming agent ke taur par use hota hai. Yeh smooth texture deta hai, acha adhesion provide karta hai, aur spreadability ko improve karta hai. Isko usually long-wear makeup aur lip products mein daalte hain kyunki yeh products ko zyada time tak stay karta hai aur creamy feel deta hai.