Characterizing the Mechanical Properties of Fused Deposition Modelling Natural Fiber Recycled Polypropylene Composites

Abstract

Abstract:The objective of this investigation was to characterize the performance of natural fiber reinforced polypropylene composites in fused deposition modelling (FDM). Composite filaments comprising of pre-consumer recycled polypropylene with varying contents of hemp or harakeke fibers were extruded from which tensile test specimens were made using FDM. Filament and test specimens were tensile tested and properties were compared with plain polypropylene samples; the ultimate tensile strength and Young's modulus of reinforced filament increased by more than 50% and 143%, respectively, for both 30 wt % hemp or harakeke compared to polypropylene filament. However, the same degree of improvement was not seen with the FDM test specimens, with several compositions having properties lower than for unfilled polypropylene. SEM analysis of fracture surfaces revealed uniform fiber dispersion and reasonable fiber alignment, but porosity and fiber pull-out were also observed. Fiber reinforcement was found to give benefit regarding dimensional stability during extrusion and FDM, which is of major importance for its implementation in FDM. Recommendations for optimization of processing in order to enhance build quality and improve mechanical properties are provided.

Sustainable Composite Fused Deposition Modelling Filament Using Post-Consumer Recycled Polypropylene

“…The 30 wt % harakeke samples showed the most significant improvements in strength and Young's modulus of 77% and 275% respectively compared to plain post-consumer PP. Furthermore, values were generally higher than for those found using pre-consumer PP studied in a parallel study including that of the PP only filament which had strength and Young's modulus values which were 6% and 14% higher than the pre-consumer PP only filament respectively [15]. Although investigation into the different grades is necessary, the increased mechanical properties could be due to the polyester fibre content within the post-consumer polymer.…”

FDM 3D Printing of Polymers Containing Natural Fillers: A Review of their Mechanical Properties

“…In order to decrease material cost even further, a limited group of researchers investigated polyolefins, such as PE and PP, which are true low cost commodities. In the pursuit of plastic waste reduction, pre-consumer PP waste was considered in [8,44], while for obtaining a more environmentally friendly material, bio-polyethylene (bioPE) was studied in [6,13]. This material is derived from vegetable feedstocks (e.g., sugar cane, sugar beet and wheat grain) and is chemically identical to petroleum based PE.…”

“…As described previously, this is typical of semicrystalline polymers and is due to the high difference between the polymer processing temperature, which obviously must exceed the crystal melting temperature, and their glass transition temperature. To limit these problems, in [8,44] a filament spooling machine was used to achieve good tolerance, as well as a 5 mm thick PP sheet retrofitted onto the print bed to improve adhesion. On the other hand, for these materials the effect of natural fibers becomes very interesting: Melt properties increase, thus improving self-sustaining characteristics during printing.…”

“…Additive manufacturing techniques, in fact, are rapidly diffusing both in industrial and household settings, due to their many valuable characteristics [1]. If required production is limited to small scales, parts can be obtained easily [2,3,4], with limited scrap production and energy consumption [5], and without the need for expensive tools [6,7,8,9] or elaborate assembly [10]. Moreover, 3D printing techniques allow us to fabricate objects of complex shape or large thickness that are normally unobtainable through standard polymer manufacturing methods [11,12,13].…”

The Synergic Effects of FDM 3D Printing Parameters on Mechanical Behaviors of Bronze Poly Lactic Acid Composites

“…One of the most significant approaches of AM methods is fused deposition modeling (FDM), which can create samples by 3D printing technology ( Figure 1) [7]. In this technology, a layer is generated by melting the polymer with the printer head at a specific temperature [8][9][10]. In nature, many materials are renewable, and polylactic acid (PLA) is one of them, which is normally produced from corn starch.…”