Thermal ageing of polychloroprene - Effect on laser induced ignition

Understanding the ignition behaviour of polymers in oxygen-enriched atmospheres is critical for safety in various high-performance demanding applications. This work presents a novel experimental approach using a laser source for controlled, localized energy deposition to simulate ignition events. Coupled with thermal and high-speed cameras, this technique allows for the detailed monitoring of material changes and ignition time in pressurized oxygen environment. This methodology was employed to investigate the influence of thermo-oxidative ageing at 80 and 100 °C, on the ignition properties of polychloroprene (CR). To understand the ageing mechanisms, a multi-scale characterization combining DSC, DMA, and swelling tests was performed. The results indicate that the ageing process involves first antioxidant consumption together with plasticizer evaporation. Crosslinking occur when antioxidants are totally consumed. These physico-chemical modifications significantly alter the material’s ignition behaviour. Plasticizer loss reduces the reactivity of the gas phase generated during heating, while the formation of a crosslinked network inhibits thermal decomposition pathways, thus limiting the release of flammable volatiles and ultimately enhancing the ignition resistance of the aged material.