▎ 摘　　要

NOVELTY - A hollow fiber membrane is prepared by dissolving polyacrylonitrile, graphene and sodium alginate in solvent (s1) to obtain spinning dope (d1), mixing graphene with sodium alginate, solubilizing mixture in solvent (s2), reacting mixture, to obtain spinning dope (d2), injecting dope (d2) to dope (d1) and adding tetraisocyanate to obtain casting solution, extruding casting solution on reinforced base film, drawing, extruding and spinning film, providing aqueous solution of nitrogen methylpyrrolidone to obtain heterostructured hollow fiber membrane, rinsing and drying membrane. USE - Preparation of gypsum-modified sodium alginate-polyacrylonitrile hetero-reinforced hollow fiber membrane (claimed). ADVANTAGE - The method enables preparation of gypsum-modified sodium alginate-polyacrylonitrile hetero-reinforced hollow fiber membrane with high mechanical property, membrane selectivity and tensile strength, and high protein throughput characteristics. DETAILED DESCRIPTION - A bulk film is prepared by dispersing predetermined amount PVDF in N,N-dimethylacetamide as solvent, stirring mixture at 70 degrees C until the polymer is completely dissolved, maintaining mixture, defoaming to form polyvinylidene fluoride hollow fiber membrane by melt spinning method, and modifying sodium alginate-polyacrylonitrile hetero-reinforced hollow fiber membrane as base film by graphene. A casting solution is prepared by dissolving polyacrylonitrile, graphene and sodium alginate in solvent (s1) such that the ratio of polyacrylonitrile having molecular weight of 35000-6000, graphene, sodium alginate, solvent (s1) and solvent (s2) is 15-30 wt.%:5-20 wt.%:10-25 wt.%:25-50 wt.%:15-45 wt.% to obtain spinning dope (d1), mixing graphene with sodium alginate, solubilizing mixture in solvent (s2), reacting mixture at room temperature for 1-3 hours, to obtain spinning dope (d2), slowly injecting spinning dope (d2) to spinning dope (d1), adding 1-5 wt.% tetraisocyanate as pore former and continuously mixing mixture such that the stock solutions are completely mixed to obtain casting solution. A hetero-reinforced hollow fiber membrane is prepared by uniformly extruding casting solution through spinning nozzle, coating on surface of reinforced base film, drawing base film and extruding base film by godet roll, spinning film with air gap of 6-30 cm at 23 plus minus 1 degrees C, air temperature f 35 plus minus 1 degrees C and air humidity of 30 plus minus 1%, providing aqueous solution of 30 %mass nitrogen methylpyrrolidone at 50 degrees C, to obtain graphene-modified sodium alginate-polyacrylonitrile heterostructured hollow fiber membrane, rinsing graphene-modified sodium alginate-polyacrylonitrile heterostructured hollow fiber membrane with organic solvent for 20-30 hours and drying graphene-modified sodium alginate-polyacrylonitrile heterostructured hollow fiber membrane.