A New Approach to the Evaluation of Stabilizer Efficiency Under Photo‐Ageing

Summary: Elastomers are very sensitive to oxidative degradation due to the combined effect of light and oxygen. Hence, we investigate the impact of stabilizers on the evolution of molecular structure of elastomers through photo‐oxidation. While a dual processes is generally reported to describe photo‐oxidation of elastomers (oxidation by‐products formation and crosslinking), the aim of the current study is to provide a complete characterization of the efficiency of additives taking into account the dual processes: chemical changes (formation of photoproducts) and molecular structure changes (crosslinking). This work gives new insights about relationships between chemical changes and physical properties evolution of the material through ageing. We conclude that the two phenomenon are correlated to the primary peroxidation reaction and a dual efficiency does not exist for any additive.

Kinetic curves of carbonylated by‐products formation upon photooxidation of stabilized EPDM films comparing with a unstabilized reference.