Polyisobutylene is also known as "PIB" or polyisobutene, (C4H8)n), is the homopolymer of isobutylene, or 2-methyl-1-propene, on which butyl rubber is based. Polyisobutylene is produced by catalytic polymerization of a hydrocarbon C4 stream from petrochemical origin and very pure, with a very high content of isobutylene with some isoprene. The formula for PIB is: -(-CH2-C(CH3)2-)n-. A careful process control insures a very narrow molecular weight distribution. PIBs are classified by their molecular weight Molecular Weight (g/mol)
