Abstract:To regulate the pore structure and performance of polyvinylidene fluoride (PVDF) membranes, a series of PVDF/EAA composite ultrafiltration membranes were prepared by immersion precipitation phase conversion method using EAA (polyvinyl acrylic acid) as an additive and PEG400 as a porogenic agent. The effects of different EAA content and different porogenic agent PEG400 on the performance of the composite membranes were investigated by scanning electron microscopy, infrared, water contact angle, viscosity characterization, porosity, pure water flux, bovine serum protein (BSA) retention, The effects of different EAA content and different porogenic agent PEG400 content on the performance of the composite membrane were investigated using scanning electron microscopy, infrared, water contact angle, viscosity characterization, porosity, pure water flux, bovine serum protein (BSA) retention rate, flux recovery rate and contamination rate. The results showed that the addition of EAA improved the hydrophilicity of the membrane surface, and the addition of porogenic agent PEG400 improved the affinity between the casting solution and the solidification bath, accelerated the membrane formation rate, and thus formed more pores on the membrane surface, in which the pure water flux and BSA retention rate of E-3 membrane reached 271.57 L.m?2.h?1 and 64.83%, respectively. -The flux recovery rate and total contamination rate were 75.97% and 46.51%, which were 19.37% and 26.92% higher and lower, respectively, compared with the pure PVDF membrane. In contrast, the porosity of the P-3 membrane was 53.33% and the average pore size was 4.55 nm, which improved the porosity and average pore size of the P-0 membrane without a porogenic agent by about 33.33% and 88.02%, respectively; therefore, the method of EAA as additive and PEG400 as porogenic agent mentioned in this study could significantly improve the structure and permeation performance of PVDF membrane.