Development of a new polymer membrane — PVB/PVDF blended membrane

In this paper, a new polymer membrane, PVB/PVDF blending membrane, with high flux, good mechanical strength and hydrophilicity was developed. Firstly, the miscibility of PVB/PVDF blending system was investigated by method of shear viscosity and intrinsic viscosity. Then the PVB/PVDF blending membranes was prepared by phase inversion method and their properties such as microstructure of crossing section, permeability, tensile strength and flexibility, hydrophylicity were tested. Results stated: 1. The PVB/PVDF blended system is partial miscible. When the weight ratio of PVDF to PVB was in the scope of 10:0 to 6.5:3.5 and 3.5:6.5 to 0:10, respectively, the PVB/PVDF blended system was fully miscible and immiscible from 6.5:3.5 to 3.5:6.5. 2. Comparing PVB/PVDF blended membranes with PVB membrane and PVDF membrane, the permeability was both much more than that of PVB membrane and PVDF membrane, the tensile strength was slightly less than that of PVB membrane but far more than that of PVDF membrane, the flexibility is superior to that of PVB membrane and close to that of PVDF membrane, the hydrophylicity was close to that of PVB membrane but more excellent than that of PVDF membrane.