Morphological Electrical and Hardness Characterization of Carbon Nanotube-Reinforced Thermoplastic Polyurethane (TPU) Nanocomposite Plates

The impacts on the morphological, electrical and hardness properties of thermoplastic polyurethane (TPU) plates using multi-walled carbon nanotubes (MWCNTs) as reinforcing fillers have been investigated, using MWCNT loadings between 1 and 7 wt%. Plates of the TPU/MWCNT nanocomposites were fabricated by compression molding from extruded pellets. An X-ray diffraction analysis showed that the incorporation of MWCNTs into the TPU polymer matrix increases the ordered range of the soft and hard segments. SEM images revealed that the fabrication route used here helped to obtain TPU/MWCNT nanocomposites with a uniform dispersion of the nanotubes inside the TPU matrix and promoted the creation of a conductive network that favors the electronic conduction of the composite. The potential of the impedance spectroscopy technique has been used to determine that the TPU/MWCNT plates exhibited two conduction mechanisms, percolation and tunneling conduction of electrons, and their conductivity values increase as the MWCNT loading increases. Finally, although the fabrication route induced a hardness reduction with respect to the pure TPU, the addition of MWCNT increased the Shore A hardness behavior of the TPU plates.

Automated summary

The impacts of adding multi-walled carbon nanotubes (MWCNTs) on the properties of thermoplastic polyurethane (TPU) plates were investigated in terms of morphology, electrical conductivity, and hardness. TPU/MWCNT nanocomposite plates were fabricated using compression molding, with MWCNT loadings ranging from 1% to 7%. X-ray diffraction analysis indicated that the incorporation of MWCNTs increased the ordered range of the TPU polymer matrix. SEM images showed that the fabrication route used resulted in a uniform dispersion of nanotubes inside the TPU matrix, creating a conductive network for electronic conduction. Impedance spectroscopy revealed that the TPU/MWCNT plates exhibited percolation and tunneling conduction mechanisms, with increasing conductivity values as the MWCNT loading increased. Additionally, the addition of MWCNTs increased the Shore A hardness behavior of the TPU plates, despite a reduction in hardness compared to pure TPU.