The application belongs to the technical field of electrical insulation materials and
nanocomposite material preparation, and discloses a method for preparing
aramid composite insulation film by sorting long
halloysite nanotubes. In the method, the
halloysite nanotube raw material is sorted by natural settlement in water to obtain long
halloysite nanotubes, which are then compounded with
aramid nanofibers, and the composite insulation film with a dense staggered
layered structure is prepared through spray film forming,
solvent replacement and heat pressing densification treatment. The obtained film has excellent mechanical properties, insulation properties and high-temperature stability, and is resistant to acid, alkali, salt and
organic solvent corrosion, and has good
moisture-proof characteristics after hydrophobic modification. The sorting process is green and
environmentally friendly, does not require organic additives, has excellent comprehensive performance, and is suitable for high-end insulation fields such as dry-type transformers,
new energy motors and
aviation electrical appliances.