Polylactic acid and high‐density polyethylene blend: Characterization and application in additive manufacturing

Abstract

This research reports a novel polylactic acid (PLA) blend with high density polyethylene (HDPE) and polyethylene graft maleic anhydride (PE‐g‐MAH) to mitigate the PLA degradation issues associated with high temperatures, soil and water exposure. The blend was prepared with a melt blending process and directly printed with a custom‐built pellet printer to maintain the “as prepared” properties. Thermal stability was analyzed in terms of mechanical strength at different bed temperatures and postprinting aging for 10 days. Soil burial degradation and water absorption were investigated in terms of mechanical strength and effects on mass at three intervals (15, 30, 45 days). The proposed blend revealed high stability to all three degradation mechanisms due to the chemical grafting along with physical interlocking. Finally, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM) were used to confirm the enhancement in molecular interactions, melt crystallization, onset temperatures and phase distribution, respectively.

Optimization of processing conditions and mechanical properties of banana fiber‐reinforced polylactic acid/high‐density polyethylene biocomposites

“…PLA/HDPE compatibilized with PE-g-MA showed better ductility and resistance to moisture degradation than pure PLA. 13 PLA/HDPE compatibilized with ethylene-butyl acrylateglycidyl and with fibers exhibited improved thermal stability and tensile strength and reduced impact resistance. 14 Techniques that do not use compatibilizers for the manufacture of these mixtures have also been reported.…”

Partial Polymer Blend for Fused Filament Fabrication with High Thermal Stability

“…Particular to the mechanical strength, the tensile strength for PLA (55 MPa) is high as compared to ≈41 MPa of ABS, ≈45 MPa for polycarbonate (PC), ≈38 MPa for ABS/PC, ≈35 MPa for Nylon, ≈38 MPa for polypropylene (PP) [ 3 ]. However, as being a polyester, the backbone of PLA main chain is vulnerable to chemical scission due to poor thermal stability [ 11 , 12 ]. The recent work from the authors of this research has found visible degradation of C-O-C and C=O groups from Fourier transform infrared spectroscopy (FTIR) analysis due to thermal aging [ 12 ].…”

“…However, as being a polyester, the backbone of PLA main chain is vulnerable to chemical scission due to poor thermal stability [ 11 , 12 ]. The recent work from the authors of this research has found visible degradation of C-O-C and C=O groups from Fourier transform infrared spectroscopy (FTIR) analysis due to thermal aging [ 12 ]. This kind of structural deficiency can cause detrimental effects in large-scale AM applications aimed for real environments.…”

“…One of the common approaches to achieve structural stability is “melt blending” of PLA with high temperature non-biodegradable polymers (nylon, ABS) in the presence of different additives (thermal stabilizers, fillers, fibers) [ 13 , 14 ]. The researched blends of PLA with non-biodegradable polymers provide reasonable mechanical properties; however, the high composition (>25%) of non-biodegradable polymers to achieve optimal properties [ 12 , 13 , 14 ] is still a big challenge to make the blend eco-friendly as neat PLA. In this regard, one of the recent blends of PLA with less than 10% high density polyethylene (HDPE) presents good thermal properties as compared to neat PLA [ 12 ].…”

“…The researched blends of PLA with non-biodegradable polymers provide reasonable mechanical properties; however, the high composition (>25%) of non-biodegradable polymers to achieve optimal properties [ 12 , 13 , 14 ] is still a big challenge to make the blend eco-friendly as neat PLA. In this regard, one of the recent blends of PLA with less than 10% high density polyethylene (HDPE) presents good thermal properties as compared to neat PLA [ 12 ].…”