Polyisobutene (polyisobutylene) is a class of organic polymers prepared by polymerization of isobutene. The polymers often have the formula Me3C[CH2CMe2]nX (Me = CH3, X = H, F). They are typically colorless gummy solids.
Sample of polyisobutene with a molecular weight of ~1,000,000
Polyisobutylene; Poly(isobutene); Poly(isobutylene); PIB
CompTox Dashboard (EPA)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Polymerization is typically initiated with a strong Brønsted or Lewis acid. The molecular weight (MW) of the resulting polymer determines the applications. Low MW polyisobutene, a mixture of oligomers with Mns of about 500, is used as plasticizers. Medium and high MW polyisobutenes, with Mn ≥ 20,000, are components of commercial adhesives.
- ^ OPPANOL B 100 by BASF
- ^ Kenneth S. Whiteley; T. Geoffrey Heggs; Hartmut Koch; Ralph L. Mawer; Wolfgang Immel (2005). "Polyolefins". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a21_487.