Abstract
Environmental plastic pollution has exponentially increased over the last few years, resulting in 6.3 out of the 8.3 metric tons of plastic produced each year worldwide, ending up in landfills or natural environments. Much of the plastic waste is a result of wrongful disposal or improper recycling category placement. Improperly recycled plastics can occur anywhere from the household, where it is stated that only 9% of plastic is correctly recycled, to universities [1]. Besides more education on proper recycling practices, higher education systems need to investigate potential areas of instruction that would allow for plastic reuse. One area includes courses dealing with 3D printing; 3D printing filament's yearly consumption is estimated at around 30 million pounds worldwide. [2] To reduce this amount, classes using 3D printing in their curriculum should consider shredding, re-extruding, and re-using the scraps created from flawed prints – using effective recycling. Recycling is not a standard practice used as some worry the recycled filament will create inadequate prints. To demonstrate the value of using recycled polymers standard mechanical tests were done to establish that important qualities are maintained after recycling. Through multiple tensile tests run on 3D printed samples using a Universal Testing Machine (UTM) with both virgin polylactic acid or polylactide (PLA), and recycled PLA, polyethylene terephthalate (PET), and polyethylene terephthalate with glycol added (PETG) plastics, it was discovered that the ultimate tensile strength (UTS) for virgin PLA was 6343.45 psi in comparison to recycled PLA that exhibited a value of 4686.80 psi. This result showed only a 23.25% decrease in its strength. 100% PET exhibited a UTS of 4481.27 psi with a 29.36% decrease compared to the UTS of virgin PET UTS. These experiments demonstrated that the recycled filament materials show a high enough UTS to create usable and adequate prints. These results verify that 3D prints using recycled plastic found on campuses (such as scraps from 3D printing labs and PET water bottles) can be used to reduce the volume of plastic waste that universities contribute to landfills.