Mechanical and nanomechanical properties of MWCNT/PP nanocomposite

Abstract

The mechanical and nanomechanical properties of multi-walled carbon nanotube-reinforced polypropylene (MWCNT/PP) nanocomposite were investigated through tension tests (conducted on 2 wt% and 5 wt% specimens) and nanoindentation tests (conducted on 2 wt% specimens). In addition, the structural properties and topography of the nanocomposite were characterized by means of scanning electron microscopy (SEM) and Scanning Probe Microscopy (SPM), respectively. The results from the tension tests reveal an enhancement and a considerable scatter in the Young's modulus and maximum stress of the MWCNT/PP nanocomposite for both MWCNT content. For the specimens with mechanical properties lower than the average values, the SEM and SPM images revealed poor dispersion and formation of large agglomerates. The hardness (as resistance to applied load) and Young's modulus were mapped at 300 nm of displacement, for a grid of 70  70 μm 2. Through projection, the resistance is clearly divided into 3 regions, namely the PP matrix, the interphase (region close to/between MWCNTs) and the regions of the MWCNT agglomerates. The resistance deviates from low values (few MPa) to 1.8 GPa. The present experimental study provides all necessary data for the model creation and validation of the MWCNT/PP nanocomposite.

Integrity of Carbon-Fibre Epoxy Composites through a Nanomechanical Mapping Protocol towards Quality Assurance

“…Samples of~55% volume fraction were carefully prepared so as to have~1.2 µm from the upper fibres to the sample surface; indenter was selected to probe at 200 nm of displacement (below 10% of empirical rule-of-thumb, [24,25]), in order for the obtained values to represent the system matrix fibre in each case. In this way, the indentation occurs at epoxy surface (matrix) (Figure 1), while the affection of the fibres (and thus their interface) underneath is revealed through variation in resistance to applied load and load-unload curve form [26].…”

Integrating Exposure Assessment and Process Hazard Analysis: The Nano-Enabled 3D Printing Filament Extrusion Case

“…Extensive research interest has been dedicated to polymer-matrix nanocomposite materials for at least two decades [1,2], while scientific efforts are still garnered towards the advancement of this field, and extension of nanocomposite material application in fields such as automotive, packaging and biomedicine [3]. The most common materials used as nanofillers in polymer materials are carbon-based nanoparticles such as carbon nanotubes [4][5][6], nano-oxides, e.g., magnetite (Fe 3 O 4 ) [7], nanoclays [8] and nano-carbides, such as silicon carbide (SiC) [9]. Conventional processing techniques are widely established in the polymer industry, such as the compounding process that can use nano-enabled feedstock [10].…”

“…Conventional processing techniques are widely established in the polymer industry, such as the compounding process that can use nano-enabled feedstock [10]. Additionally, additive manufacturing technologies increasingly use polymeric filaments enhanced with nanoparticles for multifunctionality [4].…”