The electrically conductive, transparent, and flexible self-standing thin nanocomposite films based on copolyamide matrix (coPA:Vestamelt X1010) modified with 2D Ti3C2Tx (MXene) nanosheets were prepared by casting and their electrical, mechanical and optical properties and then, were investigated. The percolation threshold of the MXene filler within the coPA matrix was found to be 0.05 vol. %, and the highest determined electrical conductivity was 1.4 × 10-2 S·cm-1 for the composite filled with 5 wt. % (1.8 vol. %) of MXene. The electrical conductivity of the as-prepared MXene was 9.1 S·cm-1, and the electrical conductivity of the MAX phase (the precursor for MXene preparation) was 172 S·cm-1. The transparency of the prepared composite films exceeded 75%, even for samples containing 5 wt. % of MXene, as confirmed by UV spectroscopy. The dynamic mechanical analysis confirmed the improved mechanical properties, such as the storage modulus, which improved with the increasing MXene content. Moreover, all the composite films were very flexible and did not break under repeated twisting. The combination of the relatively high electrical conductivity of the composites filled with low filler content, an appropriate transparency, and good mechanical properties make these materials promising for applications in flexible electronics.
Keywords: MXene; casting; electrical properties; polymer-matrix composites (PMCs).