Preparation method of novel polyamide composite separation membrane

The invention discloses a preparation method of a novel polyamide composite separation membrane. The method comprises the following steps: grafting zwitterions onto the surface of inorganic nanoparticles by active/controllable free-radical polymerization to obtain poly-zwitterion-modified inorganic nanoparticles; dissolving acyl chloride monomer in an organic solvent to prepare an oil-phase acyl chloride monomer solution; dispersing the poly-zwitterion-modified inorganic nanoparticles and amine monomer in water to prepare a water-phase amine monomer solution, and immersing a polymer ultrafiltration membrane in the oil-phase acyl chloride monomer solution for 1-10 minutes; immersing in the water-phase amine monomer solution for 1-10 minutes to obtain a nascent state separation membrane; and rinsing, and carrying out heat treatment for 0.5-10 hours to obtain the novel polyamide composite separation membrane. The method is simple and easy to implement, has the advantages of low production cost and obvious, stable and permanent modification effect, and has favorable industrialization application prospects.