Butyl Rubber - IIR

Common NamesButyl

Chemical Name: Isobutylene Isoprene

ASTM D1418 Designation: IIR

ISO/DIN 1629 Designation: IIR

ASTM D2000/SAE J200 Type, Class: AA,BA

Description: An all-petroleum product, Butyl is a copolymer of isobutylene and isoprene and has largely been replaced by Ethylene Propylene since its introduction.

Key Use(s): Highly effective in vacuum sealing applications. Good seal for hydraulic systems.

Temperature Range: 

Standard Compound: -50°C (-50°F) to +121°C (250°F)

Hardness (Shore A): 40 to 90

Features: With outstanding low permeability to gases, Butyl is especially effective in vacuum sealing applications. It also features good to excellent resistance to ozone and sunlight aging.

Limitations: Because it is a petroleum product, Butyl has poor resistance to hydrocarbon solvents and oils, and diester-based lubricants.