Exploring the impact of UV-C radiation and UV-protective additives on SEBS thermoplastic materials

Styrene-ethylene-butylene-styrene (SEBS) thermoplastic elastomers are highly sought after for various industrial and consumer applications due to their exceptional flexibility, impact resistance, and thermal stability. However, their susceptibility to ultraviolet (UV) degradation, particularly from UV-C radiation, significantly challenges their long-term performance. This study investigates the impact of UV-C radiation on SEBS and evaluates the effectiveness of a UV protective additive in mitigating these effects. Neat SEBS and UV-protected SEBS samples were subjected to accelerated UV-C weathering for 2 weeks, and their mechanical, thermal, morphological, and chemical properties were thoroughly characterised before and after exposure. The results demonstrate that UV-C radiation significantly reduces the tensile strength of neat SEBS and induces nano-crack formation on its surface, as revealed by mechanical testing and scanning electron microscopy analysis, respectively. Furthermore, UV-C exposure negatively affects the thermal stability of SEBS, as evidenced by a decrease in the T 50 temperature determined from thermogravimetric analysis. However, incorporating the UV-protective additive significantly mitigates these detrimental effects. The UV-protected SEBS retains a much higher percentage of its original tensile strength, exhibits minimal changes in surface morphology, and maintains comparable thermal stability to the unexposed samples. These findings highlight the crucial role of UV protective additives in enhancing the resistance of SEBS to UV-C radiation, paving the way for developing more durable and weather-resistant SEBS materials for demanding applications.