Integrating Ultrathin Perovskite Nanosheets for Rigid yet Fatigue‐Resistant Elastomers

Abstract The development of rigid yet fatigue‐resistant elastomers possess a critical challenge, necessitating materials capable of enduring substantial mechanical loads while maintaining structural integrity through cycles of deformations. Despite soft materials achieving a fatigue threshold of ∼1000 J m −2 , their modulus, typically ∼1 MPa, restricts their applications. This study presents a breakthrough in designing rigid, fatigue‐resistant elastomers by controlling nanosheet orientation within the network using a shear force strategy. The elastomers achieve a high fatigue threshold of 1900 J m −2 while maintaining a high elastic modulus of 8 MPa. These superior mechanical properties are attributed to the synergistic effects of microscale alignment of nanosheets and robust interfacial bonding between the polymer chains and nanosheets at the nanoscale. When the nanosheet volume fraction is below the percolation threshold, well‐dispersed nanosheets transfer load effectively through strong interfacial bonding with the polymer, significantly suppressing fatigue crack propagation. Conversely, above the percolation threshold, agglomerated nanosheets create defects in the matrix, reducing load‐bearing capacity. The innovative elastomers demonstrate potential for a wide range of applications, including automotive components, actuators, and stretchable electronic devices, where high mechanical stability and load‐bearing capacity are essential.