polyisobutylene

noun

poly·​isobutylene

¦pälē+

: 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

Word History

Etymology

International Scientific Vocabulary poly- + isobutylene

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