Addivant
Chemical ManufacturingNew York, United States501-1000 Employees
SI Group, based in Niskayuna, New York, operates as a global chemical company focused on performance additives, process solutions, pharmaceuticals, and chemical intermediates. The current structure stems from a 2018 consolidation in which Addivant, then part of SK Capital Partners, merged with SI Group to form a single brand. Its product portfolio serves manufacturers in plastics, rubber, fuels and lubricants, oilfield services, and active pharmaceutical ingredient production. The business maintains a global footprint across multiple regions. In 2025, SI Group opened a European Innovation Centre in Four Ashes, United Kingdom, and expanded its European facilities. In March 2026, Univar Solutions expanded its distribution partnership to bring SI Group’s additives to customers across the EMEA region.