Poly Vinyl Pyrrolidone Blend Membrane Research Articles

In situ immobilization of silver on polydopamine-coated composite membrane for enhanced antibacterial properties

In this work, the polyethersulfone (PES)-based membranes were prepared via phase inversion technique in the presence of polyvinylpyrrolidone (PVP) as a pore-forming agent. Polydopamine (PDA) coating followed by silver (Ag) immobilization was then carried out on the PES + PVP blend membrane to enhance the membrane wettability and antibacterial property, respectively. In total, four different membrane samples, namely pristine PES (M1), PES + PVP (M2), PDA/PES + PVP (M3) and Ag/PDA/PES + PVP (M4) were produced. The fabricated membranes were characterized with respect to physical morphology, contact angle, pure water permeability (PWP), humic acid (HA) and Escherichia coli (E. coli) rejection as well as antibacterial activity. The pristine PES membrane (M1) was reported to remove 77.81% HA and 96.4% E. coli. With the addition of PVP into the membrane matrix, the HA and E. coli rejection of M2 membrane was further improved to 79.94% and 99.33%, respectively. Upon PDA coating, the M3 membrane recorded much higher rejection rate (89.97% and 99.85%, respectively) owing to the formation of additional layer that reduced membrane pore size. It is interesting to note that complete elimination of E. coli was able to achieve by immobilizing Ag on the M4 membrane. This membrane also exhibited the greatest antibacterial activity and the highest HA rejection among all the fabricated membranes.

Development of Cellulose Acetate – PVP blend membrane and UV irradiation treatment to increase membrane selectivity for clove oil purification

Clove oil obtained from clove leaves and stems has low oil quality. This is caused by the low levels of eugenol which is around 60-80%. The application of membrane technology to purify clove oil is constrained by the almost similar size of the eugenol and caryophyllene molecules. The aim of this study is to improve membrane selectivity by increasing the hydrophilic properties of the membrane. The eugenol will penetrate easily through hydrophilic membrane than caryophyllene. Cellulose acetate membrane was fabricated by dissolving 17 wt-% CA polymer in acetone and then casted via dry-wet phase inversion method. Poly vinyl pyrrolidone (PVP) is added to the dope solution to improve the hydrophilic properties of the membrane. The results of contact angle analysis showed that the addition of PVP by 1% was able to reduce the contact angle from 41° to 32° which means the hydrophilic increased significantly. The combination of PVP addition with nano ZnO incorporation can increase eugenol concentration from 75% to 88% but decrease the permeate flux from 6.78 to 5.33 L.m−2h−1bar−1.

Analysis of polybenzimidazole and polyvinylpyrrolidone blend membranes as separating barrier in single chambered microbial fuel cells

In present study, different blend compositions of polybenzimidazole (PBI) and polyvinylpyrrolidone (PVP) have been analyzed as polymer electrolyte membrane in single chambered MFCs. Four membranes namely, pure PBI, PBI/PVP 70:30, 50:50, and 30:70 blend ratios with increasing PVP content were casted, where the hygroscopic properties of the membranes were found enhanced with increasing PVP content. The membranes were characterized at room temperature (22+2°C) with different ion exchange (IEC) and proton conductive capacities, where an IEC of 0.06meqg−1, 0.15meqg−1, 0.24meqg−1 and 0.36meqg−1 and proton conductivity of 2.5×10−4, 4.8×10−4, 9.36×10−4 and 1.2×10−3Scm−1 were observed from pure PBI, PBI/PVP 70:30, 50:50, and 30:70 membranes respectively. As membrane electrode assemblies (MEA), the casted membranes were sandwiched in-between carbon cloths, where a maximum power and current density of 231.38±12mWm−2 and 1242±62mAm−2 were observed from 30:70 PBI/PVP fitted MFC, using mixed firmicutes as biocatalysts. A gross 84.36% COD removal from 30:70 PBI/PVP membrane indicated the added effect of PVP in blend composition with approximately 81% higher power over pure PBI membrane. The results indicate the potential efficacy of PBI/PVP blends as seperators in microbial fuel cell, for bio-energy conversion over pure PBI membrane.

Cellulose acetate/poly(vinyl alcohol) and cellulose acetate/crosslinked poly(vinyl alcohol) blend membranes: preparation, characterization, and antifouling properties

Cellulose acetate (CA)/poly(vinyl alcohol) (PVA) blend membranes have been first prepared by non-solvent induced phase separation process. The pure water flux (PWF), hydrophilicity, and porosity increased with an increment in CA/PVA compositions up to 90/10. Then, polyvinyl pyrrolidone (PVP) as additive was added into the CA/PVA (90/10) casting solution. It was found that the PWF and porosity of CA/PVA/PVP blend membranes increased initially and then declined with the addition of PVP. Meanwhile, the effect of PVP content in CA/PVA blend membranes on fouling-resistant ability was studied using oil-in-water emulsion. The result indicated that all CA/PVA/PVP blend membranes had better antifouling property than CA/PVA membrane. If the PVA content in the casting solution increased to 20 wt%, the fabricating of membrane was difficult because of the strong hydrophilicity and large swelling capacity of PVA. Therefore, PVA was first crosslinked with glutaraldehyde (GA) as the crosslinking agent, followed by in situ blended with CA and PVP to fabricating the CA/crosslinked PVA (CPVA) (80/20)/PVP blend membrane. The effect of GA and PVP content on hydrophilicity, morphology, and performance of CA/CPVA (80/20)/PVP blend membranes were also discussed in detail.

Novel CO2-Selective Cross-Linked Poly(vinyl alcohol)/Polyvinylpyrrolidone Blend Membrane Containing Amine Carrier for CO2–N2 Separation: Synthesis, Characterization, and Gas Permeation Study

This article reports structural characterizations and gas permeation properties of novel CO2-selective cross-linked thin-film composite poly(vinyl alcohol) (PVA)/polyvinylpyrrolidone (PVP) blend membranes doped with suitable amine carriers. The characterization of the active layer was carried out by thermogravimetric analysis, differential scanning calorimetry, Fourier transform infrared spectroscopy, and X-ray diffraction. Gas streams containing 20% CO2 and 80% N2 by volume were used to study the transport properties of CO2 (CO2 and N2 flux, CO2 permeability, and CO2/N2 selectivity) across the membrane. The effects of active layer thickness (34–87 μm), feed absolute pressure (1.7–6.2 atm), temperature (90–125 °C), and sweep side water flow rate (0.02–0.075 cm3/min) on CO2 transport properties across the membrane were analyzed. The maximum CO2/N2 selectivity of 370 and a CO2 permeability of 1396 barrer were obtained for the composite membrane with 40 μm active layer thickness at 2.8 atm feed side absolute pressure and 100 °C.

Polysulfone and polyvinyl pyrrolidone blend membranes with reverse phase morphology as controlled release systems: experimental and theoretical studies

Blend membranes of poly(bis phenol–A-ether sulfone) (PSF) and poly( n-vinyl pyrrolidone) (PVP) in ratios (90:10 to 10:90; with increments of 10) were prepared via solution casting technique. The membranes were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the blend is immiscible having the major phase of the blend homogeneously dispersed in the continuum of the minor phase indicating the presence of “reverse phase morphology” (RPM) by SEM analysis of the dissolution treated membranes. The interaction parameter χ PVP/PSF was calculated and the ternary phase diagram with tentative spinodal along with the super-imposed experimental cloud points has been illustrated. The symmetric spherical geometry of the dispersed phase was explained theoretically with the help of the Flory Huggins Theory. The performance of these membranes as rate controlling membranes in controlled release applications was studied by coating them on paracetamol tablets and the effect of the ratio of PVP in the blend membrane on the rate of drug release was monitored. Models of mass transfer employing Fickian principles at constant temperature and pressure were elucidated to support the experimental findings. The predicted models were found to be in excellent agreement with the experimental release profiles.