Plastics play an indispensable role in daily life, but their adverse impacts on nature and human health are becoming increasingly severe due to their non-degradability and the persistent accumulation of plastic waste. It is essential to develop biodegradable and sustainable alternatives with favorable mechanical properties. Here, we developed a dilute-solution-based strategy that enables the facile and scalable production of high strength sustainable nanocomposites with multicomponent synergistic reinforcement. Owing to the shear-flow-induced nanosheets alignment and strong interfacial interactions, the nanocomposites achieve outstanding mechanical properties, with a high tensile strength of 566.9 ± 13.5 MPa. Moreover, these nanocomposites possess electromechanical stability and thermal stability, and can fully biodegrade within 30 days in natural soil. This strategy provides an effective pathway for the design of high-performance sustainable nanocomposites.

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.