The chemical industry in China is one of China's main manufacturing industries. It valued at around $1.44 trillion in 2014, and China is currently the largest chemicals manufacturing economy in the world. The chemical industry is central to modern China's economy. It uses special methods to alter the structure, composition or synthesis of substances to produce new products, such as steel, plastic, and ethyl. Chemical industry provides building materials for China's infrastructure, including subway, high-speed train, and highway.