Effects of Graphene Nanoplatelets and Multiwall Carbon Nanotubes on the Structure and Mechanical Properties of Poly(lactic acid) Composites: A Comparative Study

Abstract

Poly(lactic acid)/graphene and poly(lactic acid)/carbon nanotube nanocomposites were prepared by an easy and low-cost method of melt blending of preliminary grinded poly(lactic acid) (PLA) with nanosized carbon fillers used as powder. Morphological, structural and mechanical properties were investigated to reveal the influence of carbon nanofiller on the PLA–based composite. The dependence of tensile strength on nanocomposite loading was defined by a series of experiments over extruded filaments using a universal mechanical testing instrument. The applying the XRD technique disclosed that compounds crystallinity significantly changed upon addition of multi walled carbon nanotubes. We demonstrated that Raman spectroscopy can be used as a quick and unambiguous method to determine the homogeneity of the nanocomposites in terms of carbon filler dispersion in a polymer matrix.

Extrusion of Polymer Nanocomposites with Graphene and Graphene Derivative Nanofillers: An Overview of Recent Developments

“…Therefore, the recent interest in the development of biodegradable materials has attracted increasing attention towards PLA nanocomposites [100]. Table 4 summarizes the very last PLA-graphenic composites prepared by means of melt blending [101][102][103][104][105][106][107][108][109][110][111] and other biodegradable and biocompatible polymers [112][113][114][115][116][117].…”

Effects of Filament Extrusion, 3D Printing and Hot-Pressing on Electrical and Tensile Properties of Poly(Lactic) Acid Composites Filled with Carbon Nanotubes and Graphene

“…All compounds used in this study are processed by two extrusion runs, and they are listed in Table 2. For estimation of the electrical percolation threshold, composite formulations with filer content ranging from 1.5 to 9 wt.% are tested, which were produced in our previous study [3]. Three types of test samples are prepared for characterization: filaments, 3D printed samples, and hot-pressed specimens.…”

“…The Young's modulus, yield strength, tensile strength, elongation, and toughness are determined, and the results are summarized in Figure 8 and Table 4. The 6 wt.% filler content was chosen based on our previous study [3] showing the maximum improvement of tensile characteristics of the filament within the range of 1.5 to 9 wt.% filler content. In general, the filaments (yellow bars in Figure 8) demonstrate of 50-150% enhanced tensile characteristics compared to the 3D printed (blue bars) and the hot-pressed (green bars) samples.…”

“…In our previous studies on the poly(lactic) acid-based nanocomposite materials filled with graphene and carbon nanotubes for 3D printing application, variety of factors are reported to govern the final nanocomposite properties, such as types and combinations of fillers, processing conditions, state of dispersion, intrinsic interactions, nucleation effect of fillers on polymer crystallization, printing parameters, etc. [2][3][4]. Due to the complexity of those factors, a variety of contradicting properties may be obtained for the nanocomposite filament materials based on poly(lactic) acid (PLA).…”

Electrokinetic Properties of 3D-Printed Conductive Lattice Structures

“…Light 3D lattices of that kind can easily be produced by additive manufacturing [22,23], including the largely-diffused 3D-printing technology based on polymer materials, such as fused deposition modeling (FDM). Recent examples of FDM products are: Kagome mesh structures made of acrylonitrile butadiene styrene (ABS) polymer [24] and simple-cubic lattices made of conducting nanocarbon-doped polylactic acid (PLA) [25]. In that case, the lattice parameter is a few millimeters wide or larger.…”