In 2005, Crompton Chemical Corporation merged with Great Lake Chemical to form Chemtura, which later spun off its antioxidant and UV stabilizer division to form Addivant in May 2013. In 2019, Addivant merged with SI Group and adopted SI Group as its commercial brand.
SI Group's wide range of specialty additive products is widely recognized in the industry. Today, SI Group combines the excellent quality of chemical companies such as Crompton Chemical, Uniroyal Chemical, and Witco Chemical, demonstrating years of heritage and innovation in the chemical industry. SI Group provides a variety of antioxidants, UV stabilizers, polymer modifiers, intermediates, and inhibitors globally, including high-performance products such as Anox®, Alkanox®, Durazone®, Flexamine®, Genox®, Lowinox®, Lowilite®, Naugard®, Naugawhite®, Octamine®, Polybond®, Ultranox®, and Weston®.