Aging Behavior and Structure–Property Relationship of Methyl Vinyl Silicone Rubber Reinforced by g‐Opal@ <scp> CeO ₂ </scp> Composites

ABSTRACT This study conducted a comprehensive comparative analysis of the mechanical properties, surface morphology, hydrophobicity, microstructure, and crystallization behavior of methyl vinyl silicone rubber (MVQ) and its composites (MVQ/opal and MVQ/g‐opal@CeO 2 ) under both extreme dry‐heat and natural aging conditions. The results demonstrated that the incorporation of g‐opal@CeO 2 significantly improved weathering resistance. Under extreme dry heat aging, the MVQ/g‐opal@CeO 2 composite exhibited a tensile strength loss of only 7.13% and a hardness increase of 4.6 HA, significantly superior to the 13.05% loss and 6.4 HA increase in pure MVQ. Similarly, during natural aging, the composite showed a minimal tensile strength decline of 5.0% compared to 10.44% for MVQ, while maintaining a high contact angle (decreasing only from 123° to 120°). These improvements were attributed to the combined effects of Ce 3+ /Ce 4+ redox‐mediated oxidative protection and UV absorption, which effectively delayed Si–C bond degradation and suppressed the formation of Si–O–Si network structures. Furthermore, prediction models based on Back Propagation (BP) neural networks were developed to characterize the evolution of tensile strength, achieving determination coefficients exceeding 0.9 under both conditions.