Butyl rubber

Butyl rubber means a copolymer of isobutylene and other monomers. Typical other monomers include isoprene and methylstyrene. A typical composition of butyl rubber is approximately 85- to 99-percent isobutylene, and 1- to 15-percent other monomers. Most butyl rubber is produced by precipitation polymerization, although other methods may be used. Halobutyl rubber is a type of butyl rubber elastomer produced using halogenated copolymers.


40 CFR § 63.482

Scoping language

The following terms used in this subpart shall have the meaning given them in 63.2, 63.101, 63.111, 63.161, or the Act, as specified after each term:

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