Elastomeric materials are essential in advanced automotive engineering for mobility, isolation, damping, fluid transfer (cooling, steering, fuel, and brake), and sealing because of their unique physio mechanical properties. Elastomers are commonly used in both static and dynamic components, such as hoses, mounts, bushes, and tires. Engine emission standards and weight optimization have caused higher temperature exposure conditions for automotive components. The steering system uses special purpose elastomers like Chlorinated Polyethylene that can deteriorate under abnormal conditions during vehicle operation or manufacturing process due to the high temperature exposure. Therefore, it is crucial to understand the causes and consequences of thermal degradation of elastomers. Thermal degradation is a significant phenomenon that changes the physiochemical properties of elastomers, which results in a product not meeting functional requirements.
This study investigates the thermal degradation behavior of chlorinated polyethylene (CPE) polymer subjected to accelerated thermal ageing conditions. Comprehensive material analyses were conducted, including FTIR, TGA, DSC and Microscopical study to evaluate chemical, thermal, and morphological changes. Ageing replication experiments were designed to simulate field-induced thermal hardening and surface cracking, aiming to establish correlation between service or process induced failures and lab-based degradation mechanisms. The results show that prolonged thermal exposure leads to dehydrochlorination, crosslinking, and embrittlement, resulting in hardening, crack initiation and propagation. This experimental study provides comprehensive understanding of ageing kinetics and failure modes of CPE materials under thermal stress, supporting more robust material selection and life prediction in high-temperature applications.