The invention discloses a crosslinking hyper branched
polymer composite
nanofiltration membrane as well as the preparation method thereof. The crosslinking hyper branched
polymer composite
nanofiltration membrane is prepared by taking an
ultrafiltration membrane as a
basement membrane and crosslinking hyper branched
polymer as a selecting layer through hyper branched polymer and the
interfacial polymerization of polybasic acid, polybasic
acyl chloride, polybasic anhydride and polybasic amine; and the
interfacial polymerization takes the
mixed solution of water and
ethanol as the water phase and n-
hexane, n-
heptane or n-
octane as the organic phase. As the hyper branched polymer has the spheroidal structure, a plurality of nano-voids exist in the interior of the molecule, so as to enable the selecting layer of the crosslinking hyper branched polymer composite
nanofiltration membrane to be looser, and leads the nanofiltration membrane to maintain
high flux and
retention rate under the lower operating pressure. The nanofiltration membrane can be used in the fields of medicament, foodstuff,
environmental protection, etc. The composite nanofiltration membrane is applicable to the separation and the condensation of high valence ions, low valence ions, neutral particles, drugs, food additives, etc.