Composite nanofiltration membrane as well as preparation method and application thereof in quantum dot purification

The invention relates to a composite nanofiltration membrane as well as a preparation method and application thereof in quantum dot purification, and belongs to the technical field of composite nanofiltration membranes. The preparation method comprises the following steps: (1) dissolving a structural unit molecule in a solvent A to obtain a structural unit molecule solution; (2) dissolving cross-linked molecules in a solvent B to obtain a cross-linked molecule solution; and (3) carrying out polymerization reaction on structural unit molecules in the structural unit molecule solution in the step (1) and cross-linked molecules in the cross-linked molecule solution in the step (2) at a two-phase solution interface, and carrying out heat treatment to obtain the composite nanofiltration membrane, the solvent A and the solvent B are immiscible with each other. The composite nanofiltration membrane disclosed by the invention can concentrate a quantum dot crude product solution, rapidly remove impurities such as an o