Large-area ultrastrong and stiff aramid nanofiber based layered nanocomposite films

One-dimensional (1D) aramid nanofiber (ANF) based nanocomposite films have drawn increasing attentions in various applications due to their excellent mechanical properties and impressive chemical and thermal stabilities. However, the large-area fabrication of aramid nanocomposite films with ultrastrong mechanical properties under mild conditions remains a great challenge. Here we present a facile superspreading-assisted strategy to produce aramid nanofiber based oriented layered nanocomposites using phase inversion process that occurs at the fully swollen hydrogel surfaces. The nanocomposite films based on ANF, carboxylation carbon tube (CNT_–COOH), poly(vinyl alcohol) (PVA), and MXene nanosheet exhibit a tensile strength of up to 870.8 ± 85 MPa, a Young’s modulus of 21.8 ± 2.2 GPa, and outstanding toughness (up to 43.2 ± 4.6 MJ/m³), which are much better than those conventional aramid nanofiber based materials. Electrical conductivity of our nanocomposite films reaches the maximum of about 1100 S/m. The fabulous mechanical properties combination and continuous production capability render our strategy representing a promising direction for the development of high-performance nanocomposites.