Investigation to evaluate the aging condition utilizing UV radiation of carbon black filled rubber compounds as measured by ATR spectroscopy

Rubber, particularly carbon black-filled rubber used in tires, plays a critical role in a world of mobility. Tires are exposed to various influences, including temperature fluctuations, dynamic mechanical loads, and exposure to solar-origin UV radiation, which can affect their durability. To investigate the effects of UV radiation on tire aging, this study aimed to identify spectral absorption ranges in specifically aged tire samples providing information about their aging condition. The study utilized samples of different rubber compounds and exposed them to UV radiation for varying durations from 48 h up to 1000 h. ATR (attenuated total reflection) spectroscopy was used to analyze the aged samples and evaluate changes in their chemical structure. The results showed consistent aging behavior across all samples, with a decrease in the intensity of the double peak at approximately 2900 cm^-1, corresponding to the C-H bond. Another aging-relevant range from 1500 cm^-1 to 1450 cm^-1, characteristic of C-H groups as well, exhibited a declining absorption trend with UV aging. The impacts on the absorption spectrum resulting from the different rubber mixtures' compositions led to a reduction in the intensity of characteristic peaks. For evaluating the aging state of used tires, the CH related peaks can be utilized.