EW Polymer Group


Butyl Rubber


Copolymer rubber of brominated Isobutylene-Isoprene, low mooney viscosity, normal cure rate grade.

Basic Properties

PropertiesUnitIndexTest Method
Product Form   Off-white Visual
Mooney  Viscosity (ML1+8,125℃) MU 32±5 ISO 289/ASTM D1646
Volatile Matter wt% ≤0.7 ISO 248/ASTM D5668
Bromine Content wt% 1.9±0.2 CENWAY METHOD
Total Ash wt% ≤0.7 ISO 247/ASTM D5667
Antioxidant (non-staining) wt% ≥0.02 CENWAY METHOD
Stabilizer wt% 1.3±0.3 CENWAY METHOD

 Cure Characteristics

PropertiesUnitIndexTest Method
FL dN•m 2.5±0.9 ISO 6502/ASTM D5289
FH dN•m 7.4±1.4 ISO 6502/ASTM D5289
ts1 min 2.4±1.5 Rotorless cur (MDR)
tc50 min 5.2±1.9 160℃×40min, 0.5°arc
tc90 min 8.3±3.3 160℃×40min,0.5°arc
Test Formulation ISO 7663/ASTM D 3958 BI IR2302 100, IRB#7 40, Zn0 5, St.A 1

Bromobutyl Rubber BI IR 2302 has superior air impermeability, outstanding performance of heat-resistance, chemical corrosion-resistance, thermal aging resistance, and good curing performance. It can be widely used for tire inner liners, medical stoppers, corrosion-resistance lining, protective clothing, shoes production and TPV industry.

Safety & Toxicity
BI IR 2302 is polymer in solid with stable performance. It is harmless and not dangerous for humans, plants and animals. For relevant safety data and reference, please refer to MSDS.

25 ± 0.5 kg/bale in EVA film.
Pallets of plywood box of 1050 kg with 42 bales.
Pallets of metal box of 1200 kg with 48 bales.

Storage Life & Conditions
Two years with keeping storage & transport under 35℃ and away from sunlight.