Preparation and characterization of renewable composites from Polylactide and Rice husk for 3D printing applications

Blends of polylactide (PLA) and rice husk (RH) were prepared using a twin-screw extruder and characterized for mechanical properties, and microstructure. Scanning electron micrographs illustrated the occurrence of phase separation in PLA/RH blends, leading to poor tensile properties. To strengthen the blend mechanical properties, methylene diphenyl diisocyanate (MDI) was added as an interfacial compatibilizer, which would improve the tensile strength and notched Izod impact of the composites containing RH (20-50 wt%). A porous morphology showing several connected voids was observed on the surface of all PLA/RH and PLA/RH/MDI composites buried in soil for specific periods of time. The size of the voids considerably increased with the RH content. RH would be an excellent filler, compatibilized with MDI, to enhance the biodegradation and mechanical properties of the resultant environment-friendly composites for 3D printing applications. Graphical abstract Preparation of biodegradable composites from rice husk for 3D printing application.