Preparation method of porous micro-nano PET fibers

The invention discloses a preparation method of porous micro-nano PET fibers. The preparation method comprises the following steps: using PET and polymer as raw materials, dissolving in a mixed solvent of trifluoroacetic acid and dichloromethane, and stirring and dissolving at room temperature to obtain a homogeneous solution; performing electrostatic spinning to obtain micro-nano composite fibers; placing the composite fibers in an extracting agent to remove the polymer until the sample is constant in weight, rinsing several times with distilled water, and drying to obtain the porous micro-nano PET fibers. The porous micro-nano PET fibers have a higher specific surface area, and improve the porosity and specific surface area on the basis of maintaining advantages of conventional electrostatic spinning PET; the preparation of porous structure can be completed only by the extraction process, so that the method is simple and easy to perform. Surfaces and inner parts of the fibers have independent through holes, and the size and number of holes can be controlled according to a mass ratio of PET to another added polymer, so that the porous micro-nano PET fibers with different specific surface areas and porosities can be obtained and are applied to the filtration field to better improve the micro-nano-particles interception effect.