Olin Corp. and Huntsman Corp., which operate major adjacent chemical plants in McIntosh, announced a definitive all-stock merger agreement to combine the two businesses, creating a North American chemical manufacturing giant with an enterprise value exceeding billion. The transaction, announced June 10, will combine complementary product lines to establish one of the continent’s largest integrated chemical manufacturers. The expanded operations will span chlor-alkali, vinyls, epoxy, polyurethane and performance products. Company officials said the combined organization will feature differentiated portfolios, balanced end markets, increased scale and a strong financial foundation. Olin CEO Ken Lane called the transaction a transformative step....