Preparation and Characterization of MWCNTs/PVDF Conductive Membrane with Cross-Linked Polymer PVA and Study on Its Anti-Fouling Performance

Abstract

Based on carboxylated multi-walled carbon nanotubes (MWCNTs-COOH), a MWCNTs/PVDF conductive membrane was prepared by a vacuum filtration cross-linking method. The surface compositions and morphology of conductive membranes were studied by X-ray photoelectron spectroscopy and high-resolution field emission scanning electron microscopy, respectively. The effects of cross-linked polymeric polyvinyl alcohol (PVA) on the conductive membrane properties such as the porosity, pore size distribution, pure water flux, conductivity, hydrophilicity, stability and antifouling properties were investigated. Results showed that the addition of PVA to the MWCNTs/PVDF conductive membrane decreased the pure water flux, porosity and the conductivity. However, the hydrophilicity of the modified MWCNTs/PVDF conductive membrane was greatly improved, and the contact angle of pure water was reduced from 70.18° to 25.48° with the addition of PVA contents from 0 wt% to 0.05 wt%. Meanwhile, the conductive membranes with higher content had a relatively higher stability. It was found that the conductive functional layer of the conductive membrane had an average mass loss rate of 1.22% in the 30 min ultrasonic oscillation experiment. The tensile intensity and break elongation ratio of the conductive membrane are improved by the addition of PVA, and the durability of the conductive membrane with PVA was superior to that without PVA added. The electric assisted anti-fouling experiments of modified conductive membrane indicated that compared with the condition without electric field, the average flux attenuation of the conductive membrane was reduced by 11.2%, and the membrane flux recovery rate reached 97.05%. Moreover, the addition of PVA could accelerate the clean of the conductive membranes.

Effect of MWCNTs surface functionalization on the characterization of PVA/MWCNTs nanocomposites

“…In order to overcome this drawback, the surface of MWCNTs needs to be functionalized by the introduction of different functional groups such as carboxyl (-COOH), amine (-NH), and hydroxyl (-OH) onto the MWCNTs surface. It has been reported in the literatures [22][23][24] that the functionalized MWCNTs (f-MWCNTs) exhibit a good dispersion in polymer matrix and form strong interfacial interaction between the MWCNTs and polymer matrix. For example, Hussain et al [8] successfully fabricated the nanocomposites of poly(vinylidene fluoride) (PVDF) with a multi-walled carbon nanotube by the solution casting method.…”

Effect of Polyvinylpyrrolidone on the Structure Development, Electrical, Thermal, and Wetting Properties of Polyvinylidene Fluoride-Expanded Graphite Nanocomposites

“…Since nanostructures are metastable structures, they are prone to agglomeration which should be avoided. Due to this reason, often surfactants such as cetyltrimethylammonium bromide (CTAB), 30 sodium dodecyl benzenesulfonate, 31 etc., are used to improve the dispersion of the fillers in water or suitable organic solvents. The selection of a surfactant is critically dependent on the filler and polymer matrices chosen.…”

The Influence of MWCNTs Amounts and PVP Aqueous Solutions on the Properties of PVA/PVP/MWCNTs Nanocomposite Membranes

“…The properties of bend polymers will bring new materials for applications which each alone can not have it. [6][7][8][9] During the past few years, polymers such as polyether sulfone (PES), polysulfone (PSf), polyninyl alcohol (PVA), polyvinyl pyrrolidone (PVP), polyvinylidene fluoride (PVDF) have been prominently utilized in the preparation of nanocomposite membranes. [4][5][6][7] Among these polymers, PVA and PVP are considered to be appropriate polymers for a variety of applications due to its unique properties such as non-toxicity, solubility in water, biodegrababe, biocompatible.…”

“…4,5 Polyvinyl alcohol (PVA) [C 2 H 4 O) n ] is a synthetic friendly polymer that has particular charateristics such as nontoxic, semicrystalline, soluble in water, biodegradable. [8][9][10] It attractes researcher's attention over the years for various branches of science such as biomedical, tissue engineering, food packing, drug delivery, water treatment, medical devices. 5,11 However, polymeric membranes generally suffer from low mechanical properties, low thermal stability and electrical conductivity.…”

“…The blending of the PVA and PVP polymers can improve the mechanical and thermal properties due to the interaction between the hydroxyl groups of the PVA and carbonyl groups present in the pyrrolidone rings of the PVP. [8][9][10] In recent years, since the blending of the PVA and PVP polymers leads to the formation of extraordinary properties of both polymer components, so blend polymers PVA/PVP has attracted a great deal of attention by many research groups and widely utilized in the electrical, biomedical, nanofiltration applications. 2,3,15 When PVA and PVP are mixed together, it takes place the interaction between the hydroxyl group of PVA and carbonyl group of PVP, so PVA and PVP are miscible in all ratios.…”