Abstract：CPCs (Conductive Polymer Composites) foam exhibits excellent characteristics such as high plasticity, energy absorption, thermal and acoustic insulation, and holds enormous potential for applications in various fields including construction, transportation, electronics, etc. However, due to the complexity of CPC processing, it is challenging to achieve controlled design of micro-porous structures, resulting in simplistic and random porous structures, which limits its further applications. Inspired by the idea that biomaterials can enhance their mechanical properties by virtue of their well-aligned anisotropic microstructures, highly aligned anisotropic porous biomimetic microstructures are constructed by a bidirectional freeze-casting process to enhance the compressive mechanical properties of CPCs foams. Compared to traditional unidirectional freezing, the compressive elastic modulus and peak stress of aligned anisotropic porous microstructured CPCs foam increase by 18.7% and 25.4%, respectively. The chances of buckling and collapsing during cyclic compression are significantly reduced, and a peak stress of 91.1% and a strain recovery of 89.6% are still maintained after 2,000 cycles of cyclic compression at 50% strain. Combined with the finite element compression simulation, the main enhancement mechanisms of compressive mechanical properties include: optimizing stress distribution, effectively avoiding plastic deformation caused by the local stress concentration; the high elastic behavior of micrometer pore wall and its 3D structure gave the bionic structure strong resilience; the highly aligned anisotropic channels provided enough deformation space, improved the deformation coordination ability, and enhanced the reversibility of the structure during loading and unloading.
2024, Vol. 45 
