Preparation method of homogeneous-reinforced PVDF hollow fiber membrane

摘要

A preparation method of a homogeneous-reinforced PVDF hollow fiber membrane includes steps of: a) preparing a reinforced matrix membrane, wherein a PVDF hollow fiber membrane is utilized as the reinforced matrix membrane; b) preparing a PVDF casting solution, wherein mass fractions of the PVDF casting solution are: PVDF 6˜20 wt %; hydrophilic polymers or hydrophilic inorganic particles 0.6˜2 wt %; pore-forming agent 6˜10 wt %; and solvent 68˜87.4 wt %; mixing the above solutes in a water bath with a temperature of 70˜90° C., dissolving for 3˜4 h with stirring, then deaerating under vacuum for obtaining the uniform PVDF casting solution; and c) preparing the homogeneous-reinforced membrane; wherein the PVDF casting solution is uniformly coated on an outer surface of the reinforced matrix membrane through a spinning spinneret, then the reinforced matrix membrane is towed by a filament guide roller in such a manner that the hollow fiber forms a membrane, then the membrane passes through an air gap with a length of 5˜20 cm and is immersed in ultrafiltered water for coagulation, in such a manner that the homogeneous-reinforced membrane is obtained; wherein a traction speed is 5˜25 cm/(r·min).