Mechanical Properties of Recycled PET/PC/MDI Composite Fabricated by 3D Printing

The environmental pollution of plastic bottles is a serious dilemma among the scientist and researcher nowadays. One of the solutions that can reduce the pollution of plastic bottles are by recycling the plastic bottles material (PET) and reusing it as 3D printing material. The objective of this study was to fabricate filament wire using the r-PET/PC/MDI composites. Next, the fabricated filament wires were used to produce samples from 3D printing machine and conduct the mechanical test on fabricated samples to determine the its mechanical properties. Firstly, the sample preparation of r-PET/PC/MDI composite with chosen composition was fabricated starting from shredding the plastic bottles using crusher machine. Then the r-PET flakes were washed and rinsed in a 2% NaOH solution before mixing the r- PET/PC/MDI composite using brabender plastograph machine. Then, composites that had been blended were crushed using crusher machine to get pellet size before used it with extruder machine to fabricate filament wire. The fabricated filament wire was tested on 3D printer to produce samples. Lastly, the mechanical tests were conducted on the samples which involves tensile, flexural and impact test to identify the mechanical properties of the r-PET/PC/MDI composite. Based on the results obtained from tensile test, samples produced by injection molding technique achieved higher tensile strength which was 22.3 MPa compared to samples produced from 3D printer, meanwhile samples produce from 3D recorded higher Young modulus which was 2.8 MPa. As for flexural strength and Flexural modulus, sample from injection molding recorded higher value for both test which was 119.8 MPa and 56.3 respectively. Finally for the impact strength of r-PET/PC/MDI composite, samples produced by injection molding shows greater value which is 0.32 J/mm² compared to samples produced from 3D printer that recorded only as 0.03 J/mm². The mechanical properties of r-PET/PC/MDI blends fabricated by using injection molding showed greater result and performed better in all conducted mechanical testing compared to samples produced by 3D printer.