Two of the world’s largest producers of styrenic polymers are tweaking their manufacturing portfolios to emphasize emerging markets and provide high-value products. Styrolution says it will close a 150,000-metric-ton-per-year polystyrene plant in Indian Orchard, Mass., by the end of the year. The plant employs 58 workers. The company blames continued overcapacity in the North American polystyrene market. At the same time, the firm plans to move production of a specialty polymer, styrene methyl methacrylate, from Indian Orchard to Decatur, Ala., where it will make the polymer in a plant that previously produced polystyrene. Styrolution says the moves align with its strategy of emphasizing high-growth products and emerging markets. Separately, Styron is expanding latex capacity in China by adding a fourth reactor to its facility in Zhangjiagang. The new capacity will serve China’s paperboard market.