Method for preparing polyvinylidene fluoride-phenolphthalein polyethersulfone blending membrane

The invention relates to a method for preparing a polyvinylidene fluoride-phenolphthalein polyethersulfone blending membrane, which comprises the following steps of: (1) blending polyvinylidene fluoride, phenolphthalein polyethersulfone, a diluent, a good solvent and an inorganic additive or organic additive; (2) placing the mixture into a high-temperature stirred tank, raising the temperature to 120 to 145 DEG C, performing stirring to form polymer solution and performing standing and defoaming; (3) forming a membrane; and (4) extracting, impregnating and drying the obtained membrane to form the polyvinylidene fluoride-phenolphthalein polyethersulfone blending membrane. The method has the advantages of preparing the membrane at relatively lower temperature, reducing the degradation of polymers and ensuring the relatively stronger strength of the membrane, along with low cost; and the prepared polyvinylidene fluoride blending membrane can achieve effective improvements in hydrophilicity and resistance to shrinkage, and has vast application prospect.