(ICIS news)--China’s Yantai Wanhua Polyurethanes plans to shut its 300,000 tonne/year methyl di-p-phenylene (MDI) unit on 8 October for scheduled maintenance, the company said on Tuesday. In a filing to the Shanghai Stock Exchange, the company said maintenance for the Yantai-based unit in Shandong province would last around 25 days. Yantai Wanhua's 200,000 tonne/year line in Ningbo, Zhejiang province would continue normal operation over the same period, according to the same filing. Yantai Wanhua is the biggest MDI producer in China.