Dilauryl thiodiproprionate

As with most polyolefins and polydienes the presence of copper has a strong adverse effect and most antioxidants are relatively ineffective. In these instances quite good results may be achieved by the use of 1% of a 50 50 phenol alkane-dilauryl thiodiproprionate blend instead of the 0.1-0.2% of antioxidants more commonly used in polypropylene. 

Tetralin Hydroperoxide. Stoichiometry of the Reaction. Initial kinetic experiments at 30°, 40°, and 50 °C. in toluene solution showed that at least 25 moles of Tetralin hydroperoxide could be decomposed by 1 mole of dilauryl thiodiproprionate. For experimental reasons the bulk of the kinetic data was obtained in the temperature region 70°-90°C. using chlorobenzene as solvent. 

Most conventional antioxidants either trap the oxy radicals or decompose the hydroperoxides (COOH). Radical traps forperoxy and alkoxy radicals are the familiar amines and phenols. Examples of peroxide decomposing antioxidants are phosphate stabilizers such as tris(nonylphenyl) phosphite (Naugard P), thioester stabilizers such as dilauryl thiodiproprionate (DLTDT), and dithiocarbamate stabilizers such as nickel di-n-butyldithiocarbamate (Naugard NBC). 

The major thioester stabilizers are dilauryl thiodiproprionate DLTDT and dis-tearyl thiodiproprionate (DSTDP) [20],... 

In addition to the use of the above phenolic and amine type antioxidants, peroxide decomposers are used to harmlessly decompose the peroxides, which otherwise could decompose to give free radical propagating species, e.g., R-0 or H-0 . Examples of such peroxide decomposers, which act synergisticaUy with the phenolic or amine antioxidants, are dilauryl- 3, 3-thiodiproprionate and tris(p-nonylphenyl)phosphite. These and others are also listed in Table 4.10, with their chemical structures being listed in Table 4.11. We note that some of the peroxide decomposers are also accelerators for sulfur vulcanization. 

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