In addition to their use as catalyst sulfidation agents, polysulfides are commonly used in the formulation of lubricant additives for extreme pressure functionality. Chevron Phillips Chemical’s polysulfides are of the general formula RSnR, where R is a linear or branched alkyl group and n = 3–5. The name polysulfides also refers to substances of general structure (R-S-R-S-R)n where R is an alkyl group. From this molecule class, Chevron Phillips Chemical offers only one product: Ryton® polyphenylene sulfide.