Custom-Shaped Multifunctional Bio-Inspired Composite (CheMBIC)

• Applicant: Professor Dr. Yixin Zhang
• Subject Area: Polymeric and Biogenic Materials and Derived Composites ; Biomaterials ; Synthesis and Properties of Functional Materials
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 553712390

The ability to build 3D structures across extended length scales (nano/micro to millimetres and larger) is important for the development of materials and systems for electronic, photonic, mechanical, and biomedical applications. 3D printing is increasingly used to produce such end-use, multi-component and multi-materials structures. However, additive manufacturing of bio-based materials still faces unmet challenges. Using 3D printing to create load-bearing constructs that simultaneously fulfil requirements (desirable for components e.g., implants for hard tissue engineering) such as biocompatibility, high stiffness, and lattice-like designs with high structural resolution, has been difficult. Interestingly, in nature, the natural (acetylated) analogue of chitosan - chitin forms remarkably robust and hard materials. These chitin-based structures are large (mm to cm length scale), have intricate shapes and are remarkably strong, stiff and fracture-resistant. These composites achieve higher mechanical properties via two distinct strategies: mineral incorporation and metal-ion crosslinking. Application of these biomimetic strategy, individually or together, could help overcome the structural and functional challenges in manufacturing custom-shaped 3D geometries using chitosan via 3D printing. CheMBIC aims to build robust, microstructurally engineered and functionally shaped materials using the biopolymer chitosan, to enable their application in load-bearing components which are traditionally developed using non-renewable constituents (mainly synthetic polymers). The objective is to overcome the structural (insufficient stiffness affecting its printability into freestanding constructs) and functional (shrinkage and deformation during drying) challenges faced in using the biopolymer chitosan to create functionally shaped components. To that end, a multidisciplinary approach, combining biomimetic hierarchical organization, crosslinking and/or mineralization strategies are pursued. By combining biomimetic metal-ion cross-linking and mineralization with 3D printing and biopolymer processing, CheMBIC seeks to manufacture chitosan-based freeform structures with previously unattainable (free-form) shape and fine substructure (such as lattice architecture) with adequate hydration-insensitive mechanical property, essential for load bearing applications ranging from biomedical to industrial and domestic components.

• DFG Programme: Research Grants
• International Connection: Belgium
• Cooperation Partner: Hemant Raut, Ph.D.