Preparation of Hydrophilic Poly(Vinylidene Fluoride) Ultrafine Fiber Porous Membranes

Hydrophilic poly(vinylidene fluoride) (PVDF) ultrafine fiber porous membranes were prepared by electrospinning PVDF/poly(vinyl pyrrolidone) (PVP)/tetraethoxysilane (TOES) from the mixed solvents of N,N-dimethylformamide and acetone. The as prepared electrospun PVDF hybrid membranes were chemical post-treated in hydrochloric acid (HCl). The TEOS within the hybrid membranes was hydrolyzed and polymerized into SiO2 gels. FT-IR spectra revealed that Si-O-Si bonds and Si-OH bonds exists on the surface of hybrid membrane. The water contact angle (CA) analysis indicated the great changes of hydrophilicity between pure PVDF membranes and chemical post-treated PVDF hybrid membranes from superhydrophobicity (151 degrees) to superhydrophilicity (0 degrees). The SEM images showed microporous structures on the surface of electrospun PVDF fibers.