Production of 3D printing filament from plastic bottles waste using a low-income settings extruder as an opportunity to reduce plastic pollution in small Island developing states

Abstract

In this study, polyethylene terephthalate (PET) bottles are transformed into filament for 3D printing using an open-source design. Three different strip widths (8 mm, 9 mm, and 10 mm) of thickness 0.25 mm were investigated and the 1.60 mm nozzle extruder produced filaments with a hollow cross section of mean diameter 1.80 mm and a tolerance of − 0.03 mm and + 0.04 mm at a temperature of 245 °C. The study revealed that the 10 mm strip width is best suited for bottles of 0.25 mm thickness for the production of 1.75 mm filaments of 100% high-quality and ethical standards. Test specimens were 3D printed at three different flow rates (100%, 125%, and 150%), and the tensile strengths were evaluated using the ASTM D638 test standard. The maximum tensile strength (31.92 MPa) was obtained from the 10 mm strip width filament at a flow rate of 150%, and the ductility of all the specimens was less than 5%. Further test revealed that PLA has a tensile strength nearly as twice as the PET filament. However, while there is currently no virgin PET filament on the market, the recycle PET filament is a suitable substitute for commercial filaments for 3D products with tensile strength in the range of 30 MPa.