Upcycling of durian husks in 3D printing processes

Abstract

With increased food waste in Singapore along with growing advocation for sustainability, this project aims to look at the potential usage of durian husks, a common food waste in Singapore, as a bio-filler material in polylactic acid (PLA) filaments for fused deposition modelling(FDM). This research project aims to contribute to the development of sustainable 3D printing materials by repurposing food waste, offering a potential solution to minimize the heavy reliance on PLA manufacturing, a promising alternative to 3D printer filament in the heart of sustainability. Two types of particles derived from durian husk were assessed for their potential integration into 3D printing PLA filament: (1) particles smaller than 0.5mm, obtained through dry blending of durian husk, and (2) fibrous particles ranging from 0.2 to 0.4mm, produced by further wet blending of the remaining material. Mechanical testing (ASTM D638 Type V) was used to assess the ultimate tensile strength and young’s modulus while differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were conducted to examine thermal stability and degradation behaviour. While incorporating higher amounts of durian husk as fillers enhances sustainability, it is essential to evaluate its impact on material properties and printability. Results indicate that 5% fibre incorporation enhances mechanical properties such as Ultimate Tensile Strength (UTS), yield strength, and young’s modulus but decreases ductility. 30% fibre content allows making of biofilament but results in excessive brittleness, limiting usability. The maximum printable fibre content is 15%, but mechanical properties are subpar compared to pure PLA. Increasing fibre content will result in nozzle clogging and poor extrusion to occur. Future work will focus on preprocessing fibre to optimize interlayer bonding, composite formulations to enhance printability and mechanical properties. By addressing these challenges, this study provides a foundation for adopting waste-derived bio composite, repurposing food waste for 3D printing, paving the way for more sustainable material innovations in manufacturing.