Preparation of Aramid–Cellulose Nanofiber Films with Improved Mechanical and Dielectric Properties Utilizing Environmentally Friendly Hydrothermal Treatment for Electrical Insulation

Finding long-term solutions to environmental issues like resource depletion and pollution is crucial. Hence, in this research, the authors prepare nanocomposite films of sustainable materials, cellulose nanofiber (CNF) and aramid nanofiber (ANF) films, using the hydrothermal method, which is an environmentally friendly approach. The effect of treatment temperature on the surface functionality, crystallinity, thermal behavior, and morphology of nanocomposite films is investigated. This analysis contributed to the conclusion that the mechanical strength of the nanocomposite films is improved due to the existence of hydrogen bonds between the nanofibers and enhanced ANF fibrillation. The tensile strength and tensile modulus increased by 123 and 24%, respectively. Furthermore, in contrast to the brittle pristine ANF and CNF films, the nanocomposite films are extremely flexible, with a total elongation that is more than 3.5 times higher. An examination of the films’ dielectric properties showed a rise in the dielectric strength of more than 55%, with a minimal dielectric loss. As a result, the ANF/CNF nanocomposite films produced by hydrothermal treatment can be efficiently used for high-strength insulating applications.