Polyimide reinforced and toughened silicon dioxide nanofiber membrane and preparation method thereof

The preparation method comprises the following steps: mixing and stirring an aqueous solution of polyvinyl alcohol and hydrolysate of tetraethoxysilane in proportion to obtain a precursor solution, and preparing a hybrid nanofiber membrane through an electrostatic spinning technology under a certain spinning condition, and finally, dipping the inorganic silicon dioxide fiber membrane in a polyimide solution for multiple times, and carrying out a curing process to obtain the polyimide/silicon dioxide composite fiber membrane. The process is simple and effective, the prepared polyimide/silicon dioxide composite fiber membrane is low in heat conductivity coefficient and good in toughness, the tensile strength can reach 19.68 MPa and is improved by about 900% compared with a pure inorganic silicon dioxide nanofiber membrane, the elongation at break can reach 3% and is improved by about 300% compared with the pure inorganic silicon dioxide nanofiber membrane, and the prepared polyimide/silicon dioxide composite fi