Unveiling the Influence of natural weathering on the nanomechanical properties of magnetorheological elastomers

• Nanoscale investigation of magnetorheological elastomer (MRE) properties after natural weathering over nine months. • Unique nanomechanical changes observed in MRE compared to bulk properties, including variations in Young's modulus, stiffness, and surface roughness. • Contrasting trends in adhesion energy and surface roughness over the nine-month weathering period. • Insights into enhancing MRE durability and functionality for real-world applications and development of resilient smart materials Examining the physical aging of materials is essential for assessing their long-term performance and determining their suitability for specific applications. Material aging involves changes from their initial state, including deterioration or degradation. A key example of such a progressive, continuous process is the aging of materials in response to natural weathering conditions. While extensive research has focused on macro- and micro-scale aging, further investigation at the nanoscale could provide a more detailed understanding of material deterioration. This study explores the nanomechanical properties of magnetorheological elastomers (MREs) after nine months of natural weathering, focusing on stiffness, elasticity, surface roughness, and adhesion at the nanometer scale. Atomic Force Microscopy (AFM) with a sharp tip affixed to a cantilever was employed to characterize these properties. After nine months of exposure to natural weathering, MREs exhibited unique nanomechanical changes compared to their bulk properties, highlighting the significance of nanoscale analysis. At the nanoscale, the nanomechanical properties of MREs, including stiffness and elasticity, exhibited noticeable alterations within the first month of exposure, followed by a gradual reduction, and slight increments observed up to the nine-month mark. Surface roughness steadily increased over the nine months, while adhesion energy initially rose during the first month before gradually decreasing by the end of the study. These findings provide valuable insights into the material's mechanical behavior and offer a deeper understanding of its structural and functional properties at the nanoscale.