Mechanisms of antioxidant action: The effect of spin traps during the processing and photooxidation of PVC

✍ Scribed by J. B. Adeniyi; S. Al-Malaika; G. Scott

• Publisher: John Wiley and Sons
• Year: 1987
• Tongue: English
• Weight: 331 KB
• Volume: 34
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1987.070340804

✦ Synopsis

Synopsis

I t is demonstrated by the use of spin traps that during the early stages of thermal processing of PVC considerable concentrations (> 3 x mol g-') of free radicals are produced which are primarily responsible for the initial products (hydroperoxides, unsaturation, and hydrogen chloride) previously shown to be formed in the polymer. From a semiquantitative analysis of these products, it is estimated that more than 50% of the radicals are formed from hydroperoxides and the rest by mechanmkion of the polymer chain. The spin traps are effective processing stabilizers in combination with a tin maleate HC1 scavenger. One of them (2-methyl-2-nitroso propane, MNP) has also been shown to be a photoantioxidant.