Wet mechanical grinding regulates the micro-nano interfaces and structure of MXene/PVA composite for enhanced mechanical properties and thermal conductivity

The applications of MXene/polymer-based functional materials have been widely reported, while the under-standing of the structural evolution of MXene/polymer composites during combination is still limited. Herein, mechanical grinding is applied for the delamination and dispersion of multilayer MXene particles in PVA aqueous solution, during which they are gradually delaminated into nanosheets. Low-field nuclear magnetic resonance spectroscopy and rheological properties analysis demonstrate that the specific surface area and exposed functional groups of MXene sheets are drastically increased, which greatly contributes to the con-struction of MXene-PVA interfacial interactions and the enhancement of gel networks. Furthermore, the exfo-liated MXene nanosheets are uniformly distributed in the resultant MXene/PVA composite films, which greatly facilitates the stress transfer and the transportation of electrons/phonons, leading to significantly improved mechanical properties and electrical/thermal conductivities. This work provides fruitful insights into the opti-mized fabrication of MXene/polymer composites.