A simple and effective method to adjust the size of micropores on the inner surface of Polyvinylidene fluoride hollow fiber membranes

Pore‐forming agents affect phase thermodynamics of solution‐case membranes, hence influencing the structure and properties of the membrane. Polyvinylidene fluoride (PVDF) membrane has many advantages, but more in‐depth research is needed regarding directional control of membrane pore size. To solve this problem, a simple and efficient method is proposed. By adjusting the percentage of polyvinylpyrrolidone (PVP) in the casting solution, pore diameter is controlled between 0.01 and 10 μm. The number density and diameter of the inner surface increased significantly with increasing PVP content. The relevance of this study lies in the modulation of the inner surface micropore size of PVDF hollow fiber membranes in a simple and efficient procedure. Highlights Adjusting the size of micropores on the inner surface. The size range of the inner surface is controlled between 0.01 and 10 μm. It is possible to regulate the pore structure by limiting PVP concentration. Significant increase in the number and size of pore on the inner surface. A simple method for regulating the size of micropores.