In a big merger of South Korean chemical firms, Lotte Chemical has agreed to buy Samsung SDI’s chemical business for about $2.5 billion. Samsung will spin off the operation and sell a 90% stake to Lotte next year. The business makes styrenic resins and polycarbonate and has $1.3 billion worth of assets. Lotte is also buying Samsung’s fine chemicals business for about $200 million. Lotte, once known as Honam Petrochemical, has grown precipitously via mergers in recent years, such as its purchases of Malaysia’s Titan Chemicals and South Korea’s Lotte Daesan Petrochemical. It is now number 26 in C&EN’s Global Top 50 ranking of chemical producers. Lotte is trying to enter the U.S. market via an ethylene cracker joint venture with the polyvinyl chloride maker Axiall. Samsung, meanwhile, will use the proceeds from the sale to grow its battery materials business. The company plans to invest $1.8 billion in batteries over the next five years.