Effects of micrometre-sized graphite flake to reinforce the performances of poly(lactic acid) thermoplastic biocomposites

Abstract

Biocomposites of poly(lactic acid) (PLA) and micrometre-sized graphite (GP) flake powder with 0-30 wt% GP contents have been prepared using extrusion moulding followed by compression moulding. The pure PLA and PLA-GP composites (PGC) have been examined by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy (RS), X-ray diffraction (XRD) technique, scanning electron microscopy (SEM), transmission electron microscopy (TEM), mechanical and micromechanical testing, differential thermal analysis (DTA) and thermogravimetric analysis (TGA). FTIR spectra confirm the physical bond formation between GP and PLA. RS distinguishes the D-band spectra of pure PLA and PGC. XRD shows a partially crystalline structure in the PLA. SEM and TEM exhibit a clear dispersion of GP particles in PLA matrix at lower loading and aggregates at higher loading. With an increase of filler content, the tensile and flexural strengths decrease, but the Young's and tangent moduli are observed to increase by 58% and 77%, respectively. These increments represent an increase in the stiffness of the materials and are found to be consistent with the theoretical values. A decrease in microhardness with increase in filler content is also observed. Both the DTA and TGA reveal an increased thermal stability of the composites.

Reactive processing-microstructure-mechanical performance correlations in biodegradable poly(lactic acid)/expanded graphite nanocomposites

“…The rougher surface confirm that the EGL and EGM nanoparticles comparatively influence the PLA matrix to higher extents. 17 …”

Factors affecting the solid particle erosion of environment pollutant and natural particulate filled polymer composites—A review

“…Impact angle is defined as the angle between the path of erodent particles and the specimen. If the erosion rate reaches maximum at intermediary impact angles [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30] then the mode of erosion is called ductile whereas if the erosion rate increases with increase in impact angle and reaches a maximum at normal impact or 90 is called as brittle mode of erosion. 34,35 Erosion studies of different composites reveal that ductile, semi-ductile and brittle modes of erosion are observed.…”

“…In order to establish high strength to weight ratio for adopting in various applications, the polymer composites are reinforced with different filler materials. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] Generally, polymer composites erosion resistance can be improved by many techniques. Fiber reinforcing is one such method to improve the erosive resistance.…”

Experimental studies of mechanical behavior and damage mechanisms of recycled flax/Elium thermoplastic composite

“…Fiber reinforced thermoplastics, are increasingly used to replace metals in numbers of industrial, namely in sporting and transport applications. [1][2][3][4][5] This is mainly due to the materials' recyclability and the fact they can be easily reground and reused. Compared to conventional materials, they also present good stiffness, excellent chemical and impact resistance, and offer greater design flexibility at a relatively low price.…”