Antidegradant Fugacity – A Review on the Fate and Mechanism of Antioxidant and Antidegradant Depletion
|Date Published||September 23, 2010|
This paper will review the chemical and environmental depletion of p-phenylendiamine antidegradants in rubber. Ozone degradation is primarily a surface phenomenon. Conversely, while much oxidation occurs near the surface, oxygen permeation provides the potential for oxidative degradation of internal tire components. Thus, the locus of reaction initiated by ozone and oxygen present requirements for both mobile and immobile antidegradants. Initially, the chemical fate of antidegradants upon reaction with ozone, oxygen and water is "analytical" depletion, i.e. the original p-phenylenediamine molecule is no longer observed. However, the products continue to serve as protectants of the rubber. Environmental leaching and depletion of antidegradants further serves to strain the chemical protection system.