Rubber Knowledge III: Styrene-Butadiene Rubber (SBR)
Styrene-Butadiene Rubber (SBR for short) is a synthetic rubber formed by the copolymerization of styrene and butadiene. It is one of the most widely used synthetic rubbers globally, accounting for over 50% of the total synthetic rubber production. Its properties lie between those of natural rubber (NR) and butadiene rubber (BR), and it is renowned for its excellent wear resistance, low cost, and high stability.
| Nature | Feature | Comparison with natural rubber (NR) |
| Abrasion resistance | Better than NR, suitable for high-friction scenarios (such as tire treads) | The wear resistance of NR is relatively poor. |
| Ageing resistance | Antioxidant and ozone resistance are superior to NR (due to the presence of benzene rings) | NR is prone to aging and requires the addition of anti-aging agents. |
| Elasticity and Heat Generation | The elasticity is slightly lower than that of NR, and the dynamic heat generation is relatively high (the formula needs to be optimized) | NR has excellent elasticity and low heat generation. |
| Low temperature resistance
| Low temperature makes it prone to hardening (the worse the situation, the higher the content of styrene). | Low temperature makes it prone to hardening. (Styrene NR has better cold resistance (-50°C remains flexible)) |
| Rubber adhesiveness | Poor self-adhesion; requires the use of an adhesive enhancer resin. | NR has excellent self-adhesion properties. |
| Cost | lower | Higher (affected by the weather) |
Styrene-butadiene rubber holds a significant position in the tire industry, providing tires with wear resistance, anti-aging properties and excellent grip. Additionally, it is widely used in: automotive components (seals, shock absorbers, etc.), industrial products (conveyor belts, Sealing Rings, etc.), building materials (waterproof sheets), medical equipment (medical rubber tubes, gloves, etc.), adhesives and coatings, etc.
Major global producers: Sinopec, PetroChina, Lanxess, Trinseo, Asahi Kasei, etc.
Product types include O-rings and custom-made items for customers.