Engineering / Materials / Butyl/IIR


Butyl Rubber/IIR


Butyl rubber is composed by copolymerizing isobutylene with a small amount of isoprene. The abbreviation IIR stands for Isobutylene Isoprene Rubber.

Common Uses:

IIR/Butyl is found in:

  • Electrical insulation

  • Ozone resistance environments

  • Tire inner tubes

  • Manufacture of adhesives, caulks, and sealants

IIRs can be formulated with only “white list” ingredients as specified in 21.CFR 177.2600 for use in applications where the elastomer will be in contact with food or beverages, ex. bottle top seal for alcohol or medical.


Standard Compound: -55°C (-67°F) to 100°C (212°F)

Special Compound (High temp):

Hardness: 50 to 80 Shore A

ASTM D1418 Designation: IIR, CIIR, BIIR

ASTM D2000 Designation: AA, BA

Standard Colors: Black

Optional Colors:


Butyl rubber is produced by polymerization of about 98% of isobutylene with about 2% of isoprene.


IIR/Butyl performs well in alcohols, ketones, dilute acids and alkalis, silicone oils and greases, water and steam, phosphate ester based hydraulic fluids, ozone, and aging and weathering.


IIR/Butyl is susceptible to aliphatic and aromatic hydrocarbons, halogenated solvents, and petroleum based oils and greases.

Techno Ad is your comprehensive supplier for all sealing solutions

Stay Connected

Join our Blog & Newsletter

    I have read & agree to Techno AdPrivacy Policy

    Congrats, You’re connected
    Check your email to confirm your subscription

    Pssst.. hey!
    You can search products here