Novel 2D Ti₃C₂T_x (MXene)-reinforced polyvinyl alcohol (PVA) nanofibers have been successfully fabricated by an electrospinning technique. The high aspect ratio, hydrophilic surfaces, and metallic conductivity of delaminated MXene nanosheet render it promising nanofiller for high performance nanocomposites. Cellulose nanocrystals (CNC) were used to improve the mechanical properties of the nanofibers. The obtained electrospun nanofibers had diameter from 174 to 194 nm depending on ratio between PVA, CNC and MXene. Dynamic mechanical analysis demonstrated an increase in the elastic modulus from 392 MPa for neat PVA fibers to 855 MPa for fibers containing CNC and MXene at 25°C. Moreover, PVA nanofibers containing 0.14 wt. % Ti₃C₂T_x exhibited dc conductivity of 0.8 mS/cm conductivity which is superior compared to similar composites prepared using methods other than electrospinning. Improved mechanical and electrical characteristics of the Ti₃C₂T_x /CNC/PVA composites make them viable materials for high performance energy applications.

The electrically conductive, transparent, and flexible self-standing thin nanocomposite films based on copolyamide matrix (coPA:Vestamelt X1010) modified with 2D Ti₃C₂T_x (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.

The preparation methodology and properties of electroconductive, electrospun mats composed of copolyamide 6,10 and Ti₃C₂T_x are described in this paper. Mats of several compositions were prepared from a solution of n-propanol. The obtained electrospun mats were then tested as piezoresistive sensors. The relative resistance (A_R) of the sensor increased with an increase in the Ti₃C₂T_x content, and materials with relatively higher electrical conductivity displayed noticeably higher sensitivity to applied pressure. The pressure-induced changes in resistivity increased with an increment in the applied force.