Fatigue Aging of Silica‐Filled Synthetic Rubber Tire Tread Compounds Under Cyclic Stress: Simulating Real‐World Operating Conditions

ABSTRACT Aging studies on elastomeric compounds have received considerable attention, owing to their extensive use in dynamic and heavy‐load applications. Tyres in service operate in a demanding environment and are exposed to cyclic mechanical loads, elevated temperatures from internal heat buildup, and ambient oxidative environments, resulting in a synergistic degradation process in which mechanical fatigue, heat, and oxidative reactions interact in ways that accelerate aging. Standard accelerated aging tests usually employ static thermal exposure but fail to capture the full spectrum of dynamic loading conditions, including cyclic strain amplitude. The present investigation focuses on the study of elastomer network modifications of a tyre tread compound coupled with cyclic stress, along with thermo‐oxidative aging, to simulate the actual conditions in the laboratory. For this purpose, styrene‐butadiene rubber–silica‐reinforced rubber, a representative formulation of the passenger tyre tread compound, was exposed to 70°C for 2, 5, and 10 days in two modes: static and dynamic in air. The mechanical, dynamic mechanical, and cyclic responses of the samples were analyzed to understand the changes in the microstructure. Additionally, the abrasion and braking potentials of the compounds were assessed using a laboratory abrasion tester (LAT100) and correlated with the viscoelastic responses.