Peroxide decomposers organic sulfides

Thiolsulfinates and their reaction products play an important role in the preventive antioxidant activity observed with organic sulfides and disulfides. An investigation of the decomposition of cumene hydroperoxide in benzene at 25°C in the presence of tert -butyl tert-butanethiolsulfinate has shown that the actual peroxide decomposer is an acidic species whose activity is affected by the basic character of the S-O group in the parent thiolsulfinate and in the sulfoxides. Alternative mechanisms for generating the acidic species are discussed. Although hydroperoxide decomposition occurs primarily by a polar process, the results also indicate the involvement of radical generating processes. 

To stabilize PO s against degradation during the melt processing, antioxidants (e.g., hindered phenols, sulfide esters, organic phosphites, secondary aromatic amines, and hindered amines), peroxide decomposers (usually a phosphite) and frequently acid acceptors (e.g., calcium stearate) are used. For special applications metal deactivators are also added. 

Secondary antioxidants, often called peroxide decomposers, also may be further categorised as stoichiometric peroxide decomposers and catalytic peroxide decomposers. The former are represented by, for example, phosphites the latter by organic sulfides and their transformation products. 

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