Full definition
Polybutadiene rubber — a synthetic elastomer produced by polymerization of 1,3-butadiene, offering the best resilience (rebound elasticity up to 85%), lowest heat buildup under dynamic loads, and excellent low-temperature flexibility (Tg = -100 to -110°C) among diene rubbers. Properties: abrasion resistance comparable to NR, tensile strength 8-17 MPa (lower than NR when unfilled), elongation 300-600%. BR alone has poor processability and tack, so it is almost always blended: 20-40% BR in NR or SBR improves resilience and low-temperature performance. ASTM D2000 classification: AA. Primary applications: tire treads and sidewalls (largest consumer), industrial flooring, conveyor belt covers, golf ball cores, shoe soles, and vibration isolation mounts. Catalysts determine microstructure: high-cis (>96%, best elasticity, Nd or Co catalyst), medium-cis (Li catalyst, easier processing). Annual global production: ~3 million tonnes.