Interfacial properties of polyethylene/Ti₃C₂T_x mxene nanocomposites investigated by first-principles calculations

MXenes have recently emerged as promising candidates for reinforcements in polymer-based nanocomposites, due to their combination of mechanical and electronic properties with the presence of functional groups at the surface. These terminations, may dramatically affect their intrinsic electronic properties, as well as MXene dispersion and interfacial bonding in composites. Therefore, in order to provide a deeper understanding of the functional groups influence in polymer nanocomposites, we addressed the interfacial interaction between polyethylene (PE) and Ti3C2Tx MXene with different functional groups (Tx=O, F or OH) using the Density Functional Theory (DFT) framework. The cohesion at the interface followed the order O > F > OH, as a result of the formation of hydrogen bonds and lower amount of charge transfer. Moreover, this simulation enabled to predict conductive PE-MXene composites that could be used in different applications, such as Electromagnetic Interference Shielding (EMI) or artificial muscles. Finally, the findings in this work point towards the relevance of tailoring MXenes' surface chemistry in order to tailor MXenes/polymers properties in nanocomposites.