Robust preparation and reinforcement mechanism study of PVDF hollow fiber membrane with homogeneous fibers

Abstract

The homogeneous fiber-reinforced PVDF hollow fiber membrane was prepared successfully through dry-wet spinning process based on nonsolvent induced phase separation (NIPS) method. The three homogeneous fibers were evenly distributed in the separation layer (membrane matrix), and parallel to the axis of the membrane. The reinforcement mechanism was studied based on the change of structure and tensile properties of fibers before and after dry-wet spinning. The mechanical properties of the membrane reinforced by homogeneous fibers were improved significantly, which could meet the long-term use. Its breaking strength could reach 8.3 MPa, which was four times bigger than that of membrane without fiber reinforcement. And its pullout force could reach 4.48 N, which was sixteen times greater than that of polyester fiber-reinforced membrane. Meanwhile, its separation properties can still reach the level of the membrane without fiber reinforcement. In particular, the membranes properties could be adjusted by using the homogeneous fibers with different structures.