Asahi Kasei Corp. (TYO:3407) has formed an agreement with Singaporean-based Shell Eastern Petroleum Pte. Ltd. regarding the purchase of sustainable butadiene derived from plastic waste and biomass. By the end of fiscal 2021, Asahi Kasei intends to introduce this sustainable butadiene at its synthetic rubber plant in Singapore, as well as use this butadiene here to begin producing and marketing…