▎ 摘　　要

NOVELTY - Preparation of nanofiltration membrane involves preparing a film casting liquid, coating the film casting liquid on a nonwoven fabric to form a base film, contacting the base film with an aqueous phase solution containing amine monomer and an organic-phase solution containing acid chloride monomer in sequence to form a polyamide functional layer on the base film, treating with a solution containing 2-5C diamine substance to crosslink inside the base film, treating with a solution containing acid anhydride and tertiary amine to imidize the polyamide functional layer, treating with a solution containing 6-10C diamine substance to crosslink the base film and the polyamide functional layer and to crosslink the interior of the polyamide functional layer, post-treating, and drying. The film casting liquid contains a polymer, a solvent and nanoparticles. USE - Preparation of nanofiltration membrane (claimed). ADVANTAGE - The method enables preparation of nanofiltration membrane with excellent retention effect, and tolerance in strong polar organic solvent, and high flux, and stability for a long period of time.