Cocoa Shell Waste Biofilaments for 3D Printing Applications

In this study, biofilaments based on cocoa shell waste, a by-product of the chocolate industry, and biodegradable poly(e-caprolactone), PCL, have been prepared using a single-screw extruder. Micronized cocoa shell waste is compounded in the polymer up to 50% by weight without significant alteration of its crystalline structure. Resultant elastic (Young's) modulus of biofilaments remains close to that of pure PCL. Scanning electron microscopy results indicate that micronized cocoa shell waste is homogeneously dispersed in the polymer during the extrusion process. Detailed thermal characterization measurements on the extruded filaments allow tuning of the fused deposition modeling 3D printing parameters. 3D printed items display a well-defined structure with good adhesion between deposition layers and fine resolution. Hence, with this simple and solvent-free fabrication technique, uniformly structured cocoa shell waste biofilaments can be produced in a very reproducible manner and can be used in 3D printing of diverse objects with potential household and biomedical applications.