poly·​isobutylene | \¦pälē+\

Definition of polyisobutylene 

: a polymer of isobutylene varying from a viscous oil to a sticky or rubbery solid especially : an elastomer (C4H8)x that is formed at a low temperature (as −100° C) in the presence of a metal halide catalyst (as boron trifluoride) and that cannot be vulcanized unless a small amount of a proportion of isoprene or other diolefin has been incorporated with the isobutylene before polymerization — compare diisobutylene, synthetic rubber

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History and Etymology for polyisobutylene

International Scientific Vocabulary poly- + isobutylene

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