A Study on Suitability of Recycled Polyethylene Terephthalate for 3D Printing Filament

Abstract

This paper presents a novel 3D printing technology using recycled polyethylene terephthalate (PET) to produce a 3D printing filament. The commonly used 3D printing filaments are acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA), but they are very expensive and not environment friendly.There is a great interest about how the filament should be made from recycled materials and be eco-friendly. In addition, there has been extreme growth and excitement about the possibilities of using 3D printing technology to boost world economy. In this research, the recycled waste PET materials were converted into high value and useful products such as dog bones test samples, 3D printing filaments, mobile robot chassis, drone blades etc. This technology involves the conversion of a computer aided designed (CAD) file into a 3D physical object. The aim of this research was to find recycled PET specification and extrusion parameters for 3D printing filament. The American Society for Testing and Materials (ASTM) standard dog bones were printed from a Reprap printer to test mechanical and thermal characteristics. The mechanical and thermal properties of recycled PET such as melt flow, tensile strength, Young modulus, and yield strain were observed to go along with the printed PLA filament parameters. It has been found that recycled PET has melt flow index=2.85g/10min, tensile strength=35.7 Mpa, Young’s modulus=2457 Mpa, melting temperature=250 °C, extruding temperature=250-260°C. These properties compare well with the commercial filaments hence within acceptable range, making recycled PET fit as a 3D printing filament. The results obtained contribute to practice by providing parameters that can be used during recycling process of PET and also conservation of the environment through recycling. The result also contributes to theory by providing the properties of recycled 3D printed PET.