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