Mechano‐Plastic Pyrolysis of Dynamic Covalent Polymer Network toward Hierarchical 3D Ceramics

Shaping ceramics into complex 3D geometries is desirable yet challenging, particularly those with structural hierarchy spanning different length scales. A mechano‐plastic pyrolysis process that overcomes this limitation is reported. In addition to taking advantage of the moldability of organic polymers, the process uniquely incorporates mechano‐plasticity via dynamic covalent bond exchange for reconfiguring the shape of a preceramic polymer. The combined steps result in simultaneous shape control at both micro‐ and macro‐scales. Further pyrolysis leads to complex ceramic structures that are otherwise difficult to produce. To enable this process, rational design of the polymer network is required to satisfy an unusual combination of mechano‐plasticity and pyrolysis. Overall, the process offers an avenue for efficient fabrication of hierarchical 3D ceramic structures suitable for engineering applications. Fabrication of macroscopic 3D ceramics with simultaneous control at the microscopic scale represents an ongoing challenge. By exploring the mechano‐plasticity of a preceramic dynamic covalent polymer followed by pyrolysis, 3D ceramics with structural hierarchy spanning macroscopic and microscopic scales are produced.