Surface Modification of Poly(Vinylidene Fluoride) Microporous Membrane by Ferric Hydroxide Sol-Gel

Abstract

Surface modification of poly(vinylidene fluoride) (PVDF) membrane was accomplished by the adsorption of ferric hydroxide sol to impove its hydrophilicity. The adsorption curves of the membranes were analyzed by weight measurements, and the typical results showed a two-platform character in low concentration. The effects of the adsorption time, the ferric hydroxide sol concentration, the test temperature, as well as the water cleaning time on the adsorption amount were observed. Attenuated total reflection-Fourier transform infrared spectroscopy (ATR/ FTIR) analysis showed that the adsorption of ferric hydroxide sol on poly(vinylidene fluoride) microporous membranes (PVDFMM) is effective. The membranes hydrophilic performance was represented by water contact angle measurements. The water contact angles changes from the virgin 128°to the lowest value 81.90° in the range of 0~0.10 mol/L ferric hydroxide aqueous solution. The results indicated that ferric hydroxide sol can be immobilized on the PVDF films by adsorption, and the membrane hydrophilic performence increases with the increase of the adsorption amount of the ferric hydroxide sol onto the PVDF membrane surface.

Effect of TiO₂ Nanoparticles on Cellulose Acetate Microporous Membrane Performance

“…The CA films were sliced into rectangular strips of 3×4 cm 2 in size and disks of 10 cm in diameter respectively, washed with ethanol and dried in an electric constant temperature drying oven at 80.0±0.2 °C for 10 h. At least 3 pieces of membranes were soaked in a fresh Titanium dioxide sol solution, which were placed in a shaking water bath at 15.0 ± 0.2 °C for 6 h, when was selected in test. Then the CA membranes were taken out of the solution and were cleaned in 200 ml pure water for 30 s and dried in a vacuum oven at 40.0 ± 0.2 °C for 24 h [8]. The adsorption amount Γ (mg/g) was determined as follows:…”