Recycling Polymer Blend made from Post-used Styrofoam and Polypropylene for Fuse Deposition Modelling

Abstract

Fuse deposition modelling (FDM) has become a revolutionary manufacturing technology as it offers numerous advantages, including freedom of fabrication, mass customisation, fast prototyping, and cost-effectiveness. Thermoplastic material is commonly used as feedstock for FDM process. The current state of material development, the recycled plastic material also can be used as printing material for FDM machine. Expanded polystyrene (EPS) has been extensively used as packaging materials for many industries but rarely be recycled, as its relatively large volume with minimal weight is unconducive for transportation. This research aimed to utilize EPS waste and turn it into FDM feedstock. This research also aims to enhance the properties of recycled polystyrene (rPS) made from EPS waste by blending it with polypropylene (PP). Different ratios of rPS/PP blends were prepared and extruded into FDM filament using filament extruder. The formulated filaments were printed into specimen using FDM machine. This research found the filament made from rPS/PP blends can be printed into specimen with good printing quality if the nozzle temperature controlled at 240° C with 120 % extrusion rate. With this printing parameter, the specimen printed with rPS/PP blend filament exhibit the greatest adhesion between the deposited layers without any visible voids or gaps. Besides, the printed specimen with rPS/PP blends possess lower tensile strength, but higher tensile modulus as compared to the printed specimen with neat rPS. The addition of more PP decreased both tensile strength and modulus of rPS/PP blends. On the other hand, the rPS/PP blends have higher thermal stability as the PP content increased. Overall, the rPS/PP blends filament shows a great potential as a feedstock material for FDM fabrication.

Recycled plastic filament made from post‐consumer expanded polystyrene and polypropylene for fused filamant fabrication

“…At same printing temperature, the printed specimen with rPS/rPP blend containing higher rPP content had more interlayers coalescence and minimized or absence of voids. A similar observation was also reported by William et al, [16] who found that the printed part with rPS/virgin PP blend at higher virgin PP content exhibited an absence of air gaps when examined under an optical microscope. As reported by Ariel Leong et al [7] and William et al, [16] the tensile strength of printed part with neat rPS and rPS/virgin PP with blend ratio of 50/50 were 34 and 25 MPa, respectively.…”

“…A similar observation was also reported by William et al, [16] who found that the printed part with rPS/virgin PP blend at higher virgin PP content exhibited an absence of air gaps when examined under an optical microscope. As reported by Ariel Leong et al [7] and William et al, [16] the tensile strength of printed part with neat rPS and rPS/virgin PP with blend ratio of 50/50 were 34 and 25 MPa, respectively. Zander et al [9] also reported that the print part with rPP/rPS with 50/50 blend ratio could achieve 23 MPa of tensile strength.…”

“…The rPP and rPS flakes were dried in aircirculated oven at 80 C for at least 4 h. Then, they were stored in a sealed container. The preparation of rPS from post-consumer EPS was referred to the method reported by Ng et al [15] and William et al [16] The preparation process for the raw materials is displayed in Figure 1.…”

“…This filament has difficulty in FFF print as the filament is significantly brittle and can easily break due to the gear bite. William et al [16] and Yap et al [6] blended the recycled polystyrene (rPS) obtained from post-consumer EPS with virgin polyethylene and PP to produce a more ductile filament. The blending of more ductile plastic materials was found to significantly improve the ductility of printed specimen.…”

Investigating effect of compatibilizer on polymer blend filament from post-used styrofoam and polyethylene for fused deposition modelling

“…Utilizing recycled material acts as a circular economy strategy where plastic waste can be utilized as feedstock for FDM to reduce negative environmental impact. Thus, many researchers are putting great efforts on recycling plastic waste and turning it into FDM feedstock [3].…”