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

Fig.1 Schematic diagram of dry-wet spinning apparatus
Fig.2 Schematic diagram of the spinneret for fiber-reinforced hollow fiber membrane
Fig.3 The morphologies of the prepared membranes: (1) cross-section, (2) partial enlargement of cross-section, (4) outer surface of: (a) M1, (b) M2, (c) M3, (d) M4; and (a3), (b3), (c3) were the interfaces between fiber and separation layer of M1, M2, M3; (d3) was the full view of M4 outer surface
Fig.4 Morphologies of fibers before (P1, P2 and P3) and after (P1-S, P2-S and P3-S) dry-wet spinning; the illustrations were the morphologies of fiber cross-section
Fig.5 The FTIR spectra (a), XRD diffraction curves (b), azimuth angle scanogram (c) and stress-strain curves (d) of fibers before and after dry-wet spinning
Fig.6 The mechanical property of prepared membranes: (a) stress-strain curves, (b) bursting strength curves; (c) schematic diagram and (d) pullout force curves of the pullout of fiber reinforcement from the membrane separation layer.
Fig.7 Schematic diagram of reinforcement mechanism
Fig.8 Pore size distribution (a), porosity and pure water flux (b), BSA rejection test (c), the change of separation flux and rejection before and after ultrasound (d); and the interface after ultrasound: (e) M1, (f) M2, (g) M3