IIR – Butyl Rubber
Butyl Rubber (IIR) is a copolymer of isobutylene with a small amount of isoprene. It is an amorphous rubber with very low permeability to gases and excellent chemical stability, making it suitable for a wide range of sealing and protective applications.
Main Features:
- Extremely low gas permeability, providing excellent air tightness.
- Excellent resistance to heat, ozone, and weathering.
- Good resistance to acids, alkalis, and polar solvents.
- Excellent damping and shock absorption properties.
- Low resilience, with poor dynamic performance.
- Good electrical insulation performance.
- Poor compatibility with most other rubbers.
- Poor resistance to oils and non-polar solvents.
Main Applications:
- Inner tubes for tires, bladder membranes, and gas-holding products.
- Sealing components for chemical equipment.
- Shock-absorbing materials and vibration isolation pads.
- Protective clothing and chemical-resistant gloves.
- Linings for tanks, ponds, and pipelines.
- Pharmaceutical stoppers and medical sealing components.
ASTM Designation Codes: AA, BA, CA
Hardness Range: 40–90 Shore A
