Antioxidants for poly(ethylene terephthalate)

Abstract

Polymers undergo oxidation reactions when heated in air. Heating of the polymer takes place at any stage of the life of the polymer, e.g. during polymerization, processing or end use of the ready product. Oxidation results in chain scission, branching, crosslinking or formation of oxygen-containing functional groups and leads to deterioration of physical properties and discoloration of the polymer. Antioxidants are added at low concentrations during production or processing of polymers to minimize the adverse effects of thermo-oxidation. Now that recycling of post-consumer polymers is of increasing importance, the use of antioxidants is a good way to avoid deterioration of physical properties and discoloration of the polymer during reprocessing.