Additive Manufacturing of Recycled Materials Using Fused Deposition Modeling

Tan, Yee Ai (2022) Additive Manufacturing of Recycled Materials Using Fused Deposition Modeling. Final Year Project (Bachelor), Tunku Abdul Rahman University College.

Text FYP Thesis_Tan Yee Ai (18WGR11290).pdf Restricted to Registered users only Download (2MB)

Abstract

Inappropriate ways to dispose disposable chopsticks and polypropylene such as abandoned leads to landfill and environmental impact. This project aims to develop a solution for the abundance of disposable chopsticks and polypropylene by utilize them into 3D composite filament. Recycled disposable chopsticks (RDC) act as natural filler while recycled polypropylene (rPP) act as matrix to prepare a 3D rPP/RDC composite filament. The 3D rPP/RDC composite filaments was used in Fused Deposition Modeling (FDM) process to produce 3D printed rPP/RDC composite parts. 3D printed polymer part via FDM only used as conceptual prototypes and not functional components due to poor mechanical properties of the neat polymer. The alkali treatment of RDC fibre with sodium hydroxide (NaOH) is to remove the organic component such as waxy layer, hemicellulose and lignin by showing the reduction in peak intensity in FTIR analysis. Alkali treatment reduced the hydrophilic tendency of RDC fibre to improve compatibility with the rPP matrix. The melt flow index (MFI) decreased as the fiber content increased, hence, the viscosity of the composite greatly increased. Low MFI indicated high viscosity of composite filaments, hence, the warping effect of polymer reduced with increased fibre content. High printing temperature caused warping effect because more energy and heating time for the composite to crystallize. Thus, the 6wt% RDC fibre content and 200˚C printing temperature showed lesser warping effect on 3D printed parts. The thermal stability increased as the fiber content in composite increased because of formation of char which act as barrier layer between the heat source and the polymer composite. However, the tensile strength and elongation at break of the rPP/RDC composites reduced as the fiber content increased because more air gaps formed when fibre content increased as shown in fracture surface of printed specimens by SEM analysis because of the poor adhesion between adjacent layer and less coalescence within printed layers. The printed specimen at printing temperature of 210˚C showed highest tensile strength and lowest elongation at break percentage among the 200˚C and 220˚C printing temperature. However, the tensile strength and elongation at break percentage of all 3D printed rPP/RDC composite parts were higher than the 3D parts printed by commercial wood plastic composite filament. Hence, the 3D rPP/RDC composite filament might be able to replace the commercial wood plastic filament because of its low-cost production, ease of processability and similar in color. A face shield frame was printed using the rPP/RDC composite filament. Besides, the composite filament also can be used to produce prototypes such as architecture model and direct part production such as face shield frame, drill guide and many more for low-cost production and light weight since the application does not require high tensile strength.