What are the key cost and demand drivers for styrene-butadiene rubber (SBR) prices in China?

What are the key cost and demand drivers for styrene-butadiene rubber (SBR) prices in China?
SBR pricing is heavily influenced by feedstock butadiene, which accounts for over 90% of production costs. Recent price rallies were driven by butadiene supply cuts from plant maintenance in Shandong and Nanjing, coupled with restarts of downstream SBS and BR units boosting demand. Producer price hikes, such as Sinopec's 300 yuan/ton increase, reinforced bullish sentiment. On the demand side, tires consume about 68% of SBR in China, with semi-steel tires using more SBR than all-steel tires. Weak tire orders and high inventory have capped upside, while geopolitical tensions and crude oil volatility add cost-side pressure. Structural shifts toward solution SBR (SSBR) for green tires are reshaping the market.