: 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


International Scientific Vocabulary poly- + isobutylene

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Dictionary Entries Near polyisobutylene

Cite this Entry

“Polyisobutylene.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/polyisobutylene. Accessed 27 Mar. 2023.

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