- Mogas-Soldevila, Laia;
- Duro-Royo, Jorge;
- Lizardo, Daniel;
- Hollyer, George G;
- Settens, Charles M;
- Cox, Jordan M;
- Overvelde, Johannes TB;
- DiMasi, Elaine;
- Bertoldi, Katia;
- Weaver, James C;
- Oxman, Neri
Motivated by the need to harness the properties of renewable and biodegradable polymers for the design and manufacturing of multi-scale structures with complex geometries, we have employed our additive manufacturing platform that leverages molecular self-assembly for the production of metre-scale structures characterized by complex geometries and heterogeneous material composition. As a precursor material, we used chitosan, a chemically modified form of chitin, an abundant and sustainable structural polysaccharide. We demonstrate the ability to control concentration-dependent crystallization as well as the induction of the preferred orientation of the polymer chains through the combination of extrusion-based robotic fabrication and directional toolpathing. Anisotropy is demonstrated and assessed through high-resolution micro-X-ray diffraction in conjunction with finite element simulations. Using this approach, we can leverage controlled and user-defined small-scale propagation of residual stresses to induce large-scale folding of the resulting structures.