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Bacterial nanocellulose (BNC) composite membrane reinforced with titanium dioxide (TiO2) and addition polyethylene glycol (PEG) were analyzed in the study. Bacterial cellulose (BC) pellicle from pineapple peel waste extract. BC pellicle was cleaned with 1% NaOH. BC was mashed with a blender and carried out a high-pressure homogenizer (HPH) method of 5 cycles at a pressure of 150 bar, filtered through a vacuum filter. Composite membrane synthesized 10 grams BNC, 1% TiO2, and 1% PEG. All were mixed and dried in an oven for 14 hours at 80℃. Morphology and crystallinity were analyzed. SEM morphology of BNC membrane added with PEG made fibers look large because they were coated with PEG. BNC/ TiO2 added with PEG surfactant was able to disperse TiO2 evenly. Results of crystallinity membrane contained 4 diffraction peaks angle 2θ: 14.5°,16.8°, 22.6°, and 25.2°. Diffraction peaks BNC with BNC/PEG increase because PEG is a plasticizer making diffraction peaks larger. 1% TiO2 nanoparticles with the addition of 1% PEG caused crystallinity value and crystallinity index to decrease because the low interaction of PEG with TiO2 is hydrophobic, TiO2 is evenly dispersed in an aqueous solution and evenly distributed on the BNC matrix. [ABSTRACT FROM AUTHOR]

Hydrogen energy is a green and efficient energy source with unique characteristics like vast availability, high combustion heat, and pollution-free emissions. Fuel cells, particularly the proton exchange membrane fuel cell (PEMFC), are at the forefront of harnessing hydrogen energy. Nanocomposite proton membranes have advantages and application prospects in fuel cell technology. This paper studies the discussion regarding the characteristics of nano-composite proton membranes and their use in fuel cells. The conclusion is that the nano-composite proton membrane has better electrical conductivity, thermal stability, mechanical properties, and relative selectivity than the ordinary proton membrane. To meet the application requirements of various fuel cells on various occasions, the performance of the nano-composite proton exchange membrane has been enhanced, improving the proton exchange membrane's effectiveness, reducing the application threshold of fuel cells, and maintaining stability to improve its efficiency. Conclusively, nanocomposite proton membranes, with their enhanced properties, hold promising potential in fuel cell applications, offering a sustainable and efficient energy solution. [ABSTRACT FROM AUTHOR]

An ion exchange membrane composed of zinc oxide and polyacrylamide (PAM) was synthesised and characterised in this study. The membrane used polyacrylamides as its base, with zinc oxide (ZnO) as its ionic conductor; the concentration of ZnO was varied, and the impact of this observed. Using FTIR spectroscopy, the synthesised membranes were analysed based on their intermolecular interactions. The surface shape and thermal characteristics of the synthetic membranes were examined with characterisation techniques that included scanning electron microscopy and thermogravimetric analysis, while a two-chamber diffusion cell was used to calculate the transport number. The absorption of water and methanol, two crucial factors, were also calculated, with Nafion R, a popular commercial membrane, being used to benchmark these findings. Increasing the amount of ionic conducting material from 0.2 g to 0.4 g per 50 ml in a crosslinked PAM solution increased the membrane's transport number from 0.76 to 0.85. There is no evidence that an increase in ionic conductor concentration affected other factors, and it is commonly deemed acceptable to disregard features such as water absorption and methanol uptake. In terms of transit, however, although Nafion and synthetic membranes proved to have identical transport numbers, the composite membrane demonstrated superior water absorption and methanol uptake. [ABSTRACT FROM AUTHOR]

Thin films from Sb2O3:In2O3 Prepare membranes of different weights, then prepare membranes using a sipn coating method with the rotation speed are (2000,3000,4000,5000,6000) rpm respectively and the rotation time is 7s. The films were examined as gas sensor against NH3gas at operating temperatures (130) oC, also sensitivity of films for gases decreases with increases temperature. The variation of the operating temperature of the films have led to a significant changes in sensor sensitivity. The gas sensor at the operating temperature of an to increasing in response time and decreasing in recovery. [ABSTRACT FROM AUTHOR]

This study explores the correlation of PEG addition to the morphology and functional groups of the bacterial nanocellulose (BNC) – TiO2 composite membrane. The methods include the production of BC pellicle from the fermentation of pineapple peel waste extract using Acetobacter xylinum. Impurities from the BC pellicle was removed by immersing it in 1% NaOH solution. BNC was synthesized by using a blender, high-pressure homogenizer and vacuum filter. The composite membranes consisted of 10 grams BNC, 1% TiO2 and PEG with different mass percentages of 0.5%, 1% and 2%. They were mixed using a magnetic stirrer and were dried at 80oC-14 hours using an oven. Dry composite membrane analyzed based on its functional groups using FTIR, respectively. The results show that FTIR analysis identified peaks of 2904 cm-1, 1174 cm-1, 2131 cm-1and 3414 cm-1, and they corresponded to C-H, C-O-C, C≡C, and O-H bond, respectively. [ABSTRACT FROM AUTHOR]

In this research, polyvinyliden fluoride (PVDF) with filler zeolite (PVDF/Z) composite membranes were prepared, characterized and evaluated. The concentrations and size of the zeolite incorporated into PVDF were varied with N,N Dimethyl Acetamide (DMAc) as solvent and the effects of zeolite on the polymer matrix were investigated in terms of performance and characteristic. The method used to synthesize the membrane is phase inversion. The membrane was characterized by FTIR to determine the functional groups, SEM to determine the surface morphology and cross-section of the membrane, EDX mapping to determine the composition and distribution of zeolite in the membrane, contact angle to determine hydrophobicity. The PVDF-Zeolite composite membrane has been success fabricated with a thickness between 0.05-0.08 mm and a pore size the average is below 2 µm so it is classified as an ultrafiltration membrane. The morphological characteristics of the membrane are porous, and from the EDX mapping it was found that the zeolite was evenly distributed on the membrane. The addition of zeolite to the polymer will reduce the contact angle of membrane, thus making the membrane more hydrophilic, there is a decrease in the contact angle from 112.40o to 104.22o and this is supported by the increasing porosity with the addition of zeolite from 2.4% to 45%. Membrane modification which is done with the addition of Zeolite as dispersed particles, can increase the value of permeability and rejection coefficient when compared to ordinary ultrafiltration membrane, with a rejection coefficient is 81.85% and permeability is 25.82 Lm-2 h-1bar−1. [ABSTRACT FROM AUTHOR]

For the purpose of semi-permeable filtration system, membrane morphological structure determines the permeation quality. Membrane surface porosity, pore size distribution, symmetric and asymmetric structure in cross-section membrane play crucial role in transport properties. Therefore, scanning electron microscopy (SEM) plays important role to visualize the microscopical pore structure of membranes. In this study, bio-based composite membranes were prepared using non-solvent induced phase separation (NIPS) method. Polyvinylidene fluoride (PVDF) was employed as the main material, while ginger extract (GE) and SiO2 nanoparticles were used as additives. SEM image in this study provide information of membrane structure in surface and cross-section part. Furthermore, quantitative data of membranes in term of overall porosity is also presented. ImageJ tools is applied as software-aided SEM images processing method. The result analysis shows that addition of GE and SiO2 increase membrane porosity up to 70.81%. [ABSTRACT FROM AUTHOR]

This work reported the synthesis of nanocomposite membrane based on chitosan /PEG/MWCNT was modified with ammonium chloride (NH4Cl) as an antibacterial agent to prevent biofouling problem in the membranes. The membrane was fabricated by inversed phase methods following an optimum condition from our latest work. In particular, the NH4Cl concentration was varied from 50 to 400 ppm. The membrane was further investigated for antibacterial test via disc diffusion and total plate counting methods towards two bacteria strains. The characterization of composite membrane was conducted by means of FTIR spectroscopy, surface hydrophilicity test, gravimetric and tensile strength measurements. The incorporation of NH4Cl into the composite membrane improved its antibacterial activity, where the zone of inhibition was found of 13 mm (E. coli) and 7.3 mm (S. aureus), at the minimum inhibition concentration of 50 and 100 ppm, respectively. The higher NH4Cl concentration, the larger inhibition zone obtained. These results were in a good agreement with the maximum bacteria-killing ratio of 98.4% (S. aureus) and 87% (E. coli). The predominant interactions between NH4Cl and membrane matrix were occurred via hydrogen bond, indicated by the remarkable shifts of O-H and N-H absorption peaks of ATR spectra. Additionally, NH4Cl insertion improved the membrane hydrophilicity, porosity, and mechanical strength. [ABSTRACT FROM AUTHOR]

Membrane technology can be applied in various industrial fields. Membrane characterization play significant role in membrane application to determine suitable membrane for the demanded process. In this study, the characteristics of (polyether sulfone) PES membranes with impregnated carbon nanotubes, TiO2 and ZnO nanoparticles were investigated. The membranes were fabricated using phase inversion technique that involved Dimethylformamide (DMF) as solvent, DI water as coagulant and PES as the polymer. The resulting composite membranes were analyzed for its porosity, rejection, pore size and pore distribution where pore size and distribution was determined by solute transport method. The porosity analysis of pure PES membrane obtained was slightly higher than the PES/CNTp-TiO2 and PES/CNTp-ZnO composite membranes, which are 42.9%, 35.55%, 33.4%, respectively. However, the resulting rejection of the solute diameter and molecular weight indicated that pure PES membranes had the lowest rejection values compared to PES/CNTp-TiO2 and PES/CNTp-ZnO composite membranes. The membrane pore size distributions were among 0.1 to 50 nm where the highest probability of pore size for pure PES, PES/CNTp-TiO2, and PES/CNTp-ZnO were 5 nm, 4 nm and 3 nm, respectively. These tests show that the addition of nanoparticles may increase the rejection value and reduce the pore size of the resulting membrane. [ABSTRACT FROM AUTHOR]

The application of composite membrane for treating high-organic level wastewater has faced several issues such as fouling and low permeate flux. In this work, ZnO nanoparticles were modified through sulfonation reaction under reflux condition and embedded into PSf membrane. The flat sheet membrane was fabricated via dry-wet phase inversion with various sulfonated ZnO (sZnO) concentration. The SEM images revealed that sZnO has good compatibility with PSf polymer and the FTIR spectra also confirmed the formation of acid sulfonate group in the composite membrane. The addition of sZnO into PSf has increased the PWF value however the overloading caused significant decline. The hydrophilicity of the membrane surface was also enhanced by incorporation of sZnO into PSf membrane. The performance evaluation presented the significant improvement in term of flux from 9.0 to 14.5 L.m−2.h-1 and selective rejection rate for ammonium (NH4+) ion up to 87%. This study suggested the application of sZnO-PSf composite membrane for cationic selective membrane. [ABSTRACT FROM AUTHOR]

Membrane fouling becomes major issue in membrane application for wastewater treatment. Many attempts have been developed to improve the antifouling properties of the membrane. In this study, the sulfonated zinc oxide (sZnO) nanoparticles were incorporated into polysulfone (PSf) membrane. The composite membrane was then surface-coated using polyvinyl alcohol (PVA) via facile dip-coating method. The characterization results showed that the facile dip-coating method successfully deposited PVA layer on the membrane surface without any defect. The FTIR result also confirmed the formation of hydrophilic groups as water-absorbing site. The hydrophilicity enhancement was also confirmed by the lowering water contact angle from 79.33° to 55.67°. The PVA coated membrane could increase the COD rejection up to ∼88% that was 8 times higher than that of uncoated composite membrane. The PVA coating also reduced the organic fouling tendency of the membrane during rubber wastewater filtration by decreasing total fouling resistance from 14.2 × 10-11 to 9.91 × 10−11 m-1. This study shows that the coating of PVA on the sZnO-PSf composite membrane can significantly improve separation performance and antifouling property without sacrificing membrane permeability. [ABSTRACT FROM AUTHOR]

This research investigates bacterial nanocellulose (BNC) composite reinforced with Titanium Dioxide (TiO2) in terms of morphology and membrane functional groups. Cetyltrimethylammonium Bromide (CTAB) was used as a surfactant. The purpose of this research is to investigate the effect of addition CTAB on the membrane composite. Bacterial cellulose (BC) pellicle was produced from the extract of pineapple peel waste. Acetobacter xylinum was used as the fermentation agent. The solution of 1% NaOH was applied for removing the BC pellicle impurities. Mechanical treatment and high pressure homogenize process had been done to synthesize BNC. The composite membranes were synthesized by using a mixture of BNC, TiO2 1%, and CTAB with different mass percentages, 0.5%, 1%, and 2%, and then the composite solution was dried by the oven for 14 hours at 80 °C. Properties of the composite membrane can be known based on its morphology and functional groups. Scanning Electron Microscope was used to observe the morphology. The results show that a higher concentration of CTAB makes BNC structure became more porous, and TiO2 particles spread more uniformly. FTIR analysis was conducted in range of 682cm-1, 862cm −1, 1041cm −1 and 3421 cm−1. Successively, they are the position of the C-OH, C-H, C-O-C, and O-H function clusters. [ABSTRACT FROM AUTHOR]

The preparation process of chitosan consists of three steps, namely deproteinization, demineralization, and deacetylation. Furthermore, chitosan modification was carried out using vanillin to produce good interactions in the membrane composite structure. Chitosan-Vanillin/Polyethylene glycol (CS-V/PEG) membranes were successfully fabricated by phase inversion technique for variations of 5, 10, 15 and 20 (wt. %). Analysis of membrane performance was carried out by testing water and methanol uptake, ion exchange capacity and methanol permeability. The results of water uptake analysis showed the highest value in CS-V/PEG 20 (47.90%), while the lowest methanol uptake was 17.80% showed by CS-V/PEG 5. In addition, the best value of ion exchange capacity and methanol permeability was obtained in CS-V/PEG 10 and CS-V/PEG 20 with values of 2.60 mmol/gram and 0.32 x 10−5 cm2/s, respectively. All membrane test results obtained indicate that the chitosan-vanillin/polyethylene glycol composite membrane has a promising potential for direct methanol fuel cell applications. [ABSTRACT FROM AUTHOR]

Ion exchange membranes are widely used in modern technologies, especially in the field of water treatment, which significantly reduce cleaning costs and provide high efficiency. For water treatment purposes, a cation exchange membrane was obtained with a surface layer of polyaniline based on a composite membrane of polytetrafluoroethylene and cellulose acetate (PTFE-AC). A membrane with a surface distribution of polyaniline was synthesized by polymerization of aniline directly in the PTFE-AC membrane matrix. The change in the membrane structure was detected using a scanning electron microscope and the characteristic absorption bands in the IR spectra of the polymers. The mass content of polyaniline in the membrane, the contact angle of the membrane with a drop of distilled water, the degree of swelling, and the porosity of the membrane were established. The main parameters of the membrane separation process, such as specific productivity, retention ability, and selectivity for heavy metal ions, were determined. The cation retention ability of the obtained membrane is not less than for some commercially available cation-exchange membranes. [ABSTRACT FROM AUTHOR]

The article deals of the development of sportswear for children involved in biathlon. Were solved: the analysis of the training activity of young biathletes was carried out; selected materials for the product; a model and rational design of a tracksuit for girls has been developed; the study of the properties and the choice of the sewing mode was carried out. In this work, to study the properties of materials, method of microscopy, methods of studying strength, thermal conductivity, permeability and toxicity of textile materials were used; for the development of a rational design - a computational-graphic method; to optimize the modes of seams - the method of mathematical modeling. As a result, the main recommendations were formulated for the design and processing technology of sportswear for children, made using composite membrane materials on a knitted basis. The area of use of the results is the clothing industry. [ABSTRACT FROM AUTHOR]

The oil and gas activities such as hydraulic fracturing requires huge quantities of sulfate-free water. The objective of this study is to design a membrane that can selectively remove sulfates from seawater. The membrane was developed by interfacial polymerization of an aqueous mixture of two diamines (TTDA and PIP) with an organic solution of TMC. The merits of the prepared membranes were characterized by a cross-flow permeation setup and evaluated under different operating pressures and temperatures. The optimum membrane (at 50%TTDA) achieved a permeate flux of 53 L/m2.h and a sulfate rejection of 96%. The permeate flux can be increased significantly by increasing either the operating pressure or temperature. However, this will be accompanied by significant reduction in the sulfate rejection. This study shows that the permeation properties can be altered and designed for a specific application by introducing a second monomer (such as the TTDA) in the aqueous diamine solution. [ABSTRACT FROM AUTHOR]

Proton Exchange Membrane Fuel cell (PEMFC) is one of the types of fuel cells that potentially able to be an alternative energy sourcethat environmentally friendly to overcome the energy crisis of fossil fuels in the future. The objective of research to product and characterize the composite membrane of chitosan-CaO phosphorylated as PEMFC. PEMFC made by chitosan and CaO with concentration variation of 0, 10, 15, 20, 25, and 30% (w/w). First, chitosan-CaOdope solution is made. Then, Crosslinking process of chitosan-CaO composite membrane is submerged in solution of 0.005glutaraldehyde and phosphorylation process is done by soaking the membrane in solution of STPP 2N. Characterization of membrane was encompassed by determination of the mechanical properties by tensile test, ion exchange capacity test, water swelling test, analysis of functional groups by FTIR, analysis of membrane morphology by SEM, methanol permeability test, and proton conductivity test. The addition of CaO 25% (w/w) is the most optimal production of phosphorylation chitosan-CaO composite membrane. The membrane exhibited stress of 32 kN/cm2, Young's modulus of 1.3 kN/cm2, ion exchange capacity of 2.413 meq/g, swelling degree at 26.65%, methanol permeability at 1.61x10−3 kg/m2s, and proton conductivity at 4.75x10−5 S/cm. Based on the analysis results, the phosphorylation chitosan-CaO 25% (w/w) composite membrane has good potentials for the application of the polymer electrolyte membrane in PEMFC. [ABSTRACT FROM AUTHOR]

In the present work, a novel investigation on the effect of different type of polymers used as membrane substrates for application in pressure retarded osmosis was systematically conducted. Three asymmetric membranes with similar pore size but different polymers; polyethersulfone (PES), polysulfone (PSf), and polyphenylsulfone (PPSU) were used. The synthesized thin film composite (TFC) membranes were able to withstand with the applied pressure of 10 bar in pressure retarded osmosis mode when 1.0 M sodium chloride was used as draw solution and deionized water as a feed solution. Results showed that the PSf-TFC membrane gives a power density of 2.15 Wm-2, which is higher than that of the PPSU-TFC and PES-TFC membranes. It was found that the PSf-TFC is the most suitable substrate in this study with ideal porosity, good water and salt permeability, and low structural parameter which enhanced the power density. [ABSTRACT FROM AUTHOR]

Proton-conducting hybrid organic-inorganic composites based on a copolymer of 4-vinylpyridine with 2-hyd-roxyethylmethacrylate and the product of hydrolytic polycondensation of tetraethoxysilane are obtained. They are charac-terized by high exchange capacity and electrical conductivity. Using the ORCA software package, quantum-chemical calculations of the geometry of the structure of an organo-inorganic composite were carried out. The calculations were carried out at the level of the density functional theory BP86/def2-SVP. The results of computer simulation allow us to relate the increase in the proton conductivity of hybrid membranes with the formation of crystallization water during the formation of the composite and the shift of the electron density from the phosphoric acid molecule to the polymer part. The bonding method (intermolecular or covalent) has no advantages in this case. In polymer synthesis, the probability of bond formation by different mechanisms is practically the same. [ABSTRACT FROM AUTHOR]

The paper is dedicated to the theory of flow in a thin plastic layer that has numerous applications in calculations of technological processes of material treatment by pressure, such as stamping and pressing of thin-walled structural elements, thin-sheet rolling, and others. Two-dimensional, averaged over the thickness of the layer mathematical formulation of the contact boundary value problem of the spreading of a plastic layer on the plane has been examined. In the framework of the general "viscous liquid" model, an approximate analytical solution has been obtained and evaluated against measurements. This solution is in good agreement with the experimental results in the area far from the free boundary and the central part of the sample. [ABSTRACT FROM AUTHOR]

ZnO-NiO nanocomposite thin films have been deposited by magnetic spin coating technique at different mixing concentrations. Magnetic spin coating technique is a novel thin film deposition technique in which a sol-gel solution is used and the substrate rotation is made magnetically. The crystal structures of the thin films have been investigated by X-Ray Diffraction (XRD). The crystallinity of obtained nanocomposite thin films improved with increasing doping concentration and the grain size values increased. The surface morphologies of the nanocomposite thin films have been studied by field emission scanning electron microscopy (FESEM). With the increase of the doping, it has been appeared that the grains of NiO structure increased on the surface. The optical properties of nanocomposite thin films have been investigated by using ultra-violet–visible (UV-Vis.) spectroscopy. It has been observed that as the doping concentration increases, the optical band gap energy is widened. [ABSTRACT FROM AUTHOR]

Polymer membrane composed of PVdC-AN/PMMA/EC with different anions of lithium salts were prepared using solution casting technique. A substantial change in ionic conductivity is observed in the vibrational and electrochemical analysis spectra, which may be due to the combined effect of ionic mobility, cation radii and dissociation constant. The conductance spectra and complex dielectric analysis shows that the sample containing LiAsF6 salt shows better performance. There is stronger interaction between oxygen atoms in the ether and carbonyl groups and lithium ions, than that with nitrogen atoms, which can found from infrared spectroscopic analysis. [ABSTRACT FROM AUTHOR]

Microporous Polyetherimide (PEI) membranes were prepared by wet phase inversion at different temperatures. The thin film composites (TFC) of polyamide on microporous PEI were prepared using meta-Phenylenediamine (MPD) and 1,3,5-Benzenetricarbonyl chloride (BTC). The ATR FTIR characterization showed the formation of polyamide (PA) on microporous PEI membrane, whereas scanning electron microscopy (SEM) revealed that a thin film of polyamide is formed on microporous PEI. The cross-sectional SEM of PEI prepared at 60 °C, showed finger like morphology and sparingly distributed balloon like morphology for PEI synthesized at 80 °C. The performance of PEI membranes and PA TFCs were ascertained by studying permeation of water and rejection of sodium chloride by reverse osmosis. The polyamide TFC with hydrophobic PEI support structures exhibited permeation of 28 to 50 lm-2h-1, with 98 – 95 % 2000 ppm NaCl rejection at 60 bar pressure. [ABSTRACT FROM AUTHOR]

The third order nonlinear optical properties of TPP incorporated PMMA thin films were probed by means of zscan technique. The thin films of the order 200-400 nm were fabricated using spin-coating technique. The UV-Visible absorption spectrum shows no variation in the absorption wavelength region with the increase of TPP concentration in PMMA matrix. The developed composite thin films exhibit strong nonlinear absorption (NLA) and nonlinear refraction (NLR) coefficients (β and n2) in the range 10-6 to 10-5 m/W and 10-13 to 10-12 m²/W respectively. The measured third order nonlinear susceptibility, χ(3) of composite thin films was found to increase with the TPP concentration. The obtained results indicate that the developed spin coated thin films are potential candidates for nonlinear optical device fabrication. [ABSTRACT FROM AUTHOR]

In this work, three different types of commercial thin film composite (TFC) membranes were selected to conduct the study. They were TFC-HR, ACM5 and Aquaporin (AQP) membranes. Water permeation fluxes of these membranes were accessed under forward osmosis (FO) and pressure retarded osmosis (PRO) configurations with deionized (DI) water as the feed. For the draw solutions, glycerol and sodium chloride (NaCl) solutions with concentrations ranged from 1 to 100 wt% and 1 to 25 wt%, respectively were utilized. In general, the water permeation performance study revealed that the PRO configuration delivered higher water fluxes for both glycerol and NaCl, irrespective of the membranes and concentration of the draw solutions used. In comparison between glycerol and NaCl at 20 wt%, NaCl exhibited 185 % and 174 % better water flux in FO and PRO configurations, correspondingly with the AQP membrane. This study disclosed that when a draw solution of lower osmotic pressure such as glycerol is used, the usage of membrane with higher porosity and hydrophilicity can improve the water flux. [ABSTRACT FROM AUTHOR]

The majority of energy was used in this period is from fossil fuel, which getting decreased in the future. The objective of this research is production and characterization of sulfonated chitosan-sodium alginate found in brown algae (Sargassum sp.) composite membrane as Proton Exchange Membrane Fuel Cell (PEMFC) for alternative energy. PEMFC was produced with 4 variations (w/w) ratio between chitosan and sodium alginate, 8 : 0, 8 : 1, 8 : 2, 8 : 4 (w/w). The production of membrane was mixed sodium alginate solution into chitosan solution and sulfonated with H2SO4 0.72 N. The characterization of the PEM was uses Modulus Young analysis, water swelling, ion exchange capacity, FTIR, SEM, DTA, methanol permeability and proton conductivity. The result of the research, showed that the optimum membrane was with ratio 8 : 2 (w/w) that the Modulus Young 8564 kN/m2, water swelling 31.86%, ion exchange capacity 1.020 meq/g, proton conductivity 8,8 x 10-6 S/cm, methanol permeability 1.90 x 10-8 g/cm²s and glass transition temperature (Tg) 100.9 °C, crystalline temperature (Tc) 227.6 °C, and the melting temperature (Tm) 267.9 °C. [ABSTRACT FROM AUTHOR]

Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm-1 and 3300 cm-1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10-2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant. [ABSTRACT FROM AUTHOR]

Epoxidised Natural Rubber (ENR) / Poly (Vinylidene Fluoride) (PVDF) (ENR/PVDF) (60:40 wt%) thin film composite membrane was prepared by using solution casting technique. The focuses of this paper are to prepare ENR/PVDF membrane with ratio of ENR to PVDF 60:40 wt%, and to study the effectiveness of treating Palm Oil Mill Effluent (POME) using the membrane. The prepared membrane was analyzed using optical microscope and the treatment of POME was investigated using dead-end stirred cell. Treated and untreated POME was analyzed to test the percentage of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) removal. Optical microscope micrographs showed that the surface of the membrane was slightly uneven. The rate of flux which passed through the membrane was 0.60 L/hm2. Both BOD and COD decreased by 23.6% and 49.32% respectively, after single treatment. This showed that the membrane can be used for POME treatment. The value of BOD and COD removal can be increased by recycling the treated POME for more than two cycles, which will be further studied by authors. [ABSTRACT FROM AUTHOR]

The manuscript reflect research work in fabrication of a triple layered composite membrane and to perform an in vitro bioactivity evaluation on composite membrane containing antimicrobial lauric acid. Poly(lactic-co-glycolic acid) (PLGA) matrix was incorporated with various amounts of nanoapatite (NAp) and lauric acid (LA) to form a triple-layered composite membrane. This membrane was prepared using a single step fabrication technique comprising of solvent casting, thermally induced phase separation and solvent leaching processes. Apatite mineralization was detected on the composite membranes within 30 days of exposure to simulated body fluid (SBF) and showed increased apatite formation at 30-60wt% of NAp content in the PLGA matrix on layer 3 (L3), that has the highest amount of NAp compared with layer 1 (L1) and layer 2 (L2) of the membrane. However, apatite mineralization was not detected on pure PLGA membrane. In addition, incorporation of LA on L1 and L2 has no influence on apatite mineral formation as none detected on these surfaces. The presence of NAp determines the formation of apatite crystals on the composite membrane. These membranes with triple layered design and bioactive properties showed potential use for guided bone regeneration purposes in dental application. [ABSTRACT FROM AUTHOR]

Herein we describe new materials for membrane gas separation process with improved selectivities towards different pairs of gases. Organic nature fillers (modified calix[4]arenes, calix[8]arenes and modified a-, ß-, γ- cyclodextrins) were used as additives to poly(trimethylsilyltricyclononene-7) (PTCNSi1)in order to study correlations between structure of the filling agent and gas transport parameters of the composite membranes. It was shown a positive influence of calixarenes and cyclodextrins as additives on permselectivity of the membranes. For instance, selectivity towards H2/CH4 gas pair increased almost in 2.4 times when calix[4]arene with Et- and tert-Bu- group was introduced into polymeric matrix. Detailed study of the PTCNSi1 adsorbtion/desortion data is presented. The obtained composites were characterized by TEM, WAXD, PALS and BET analysis. [ABSTRACT FROM AUTHOR]

The highest proton conductivity value of 0.0802 Scm-1 is obtained at 6wt% of protonated MMT added to the PVA/PEG blends. The polymer blend composite membranes are prepared with varied concentration of Poly vinyl alcohol (PVA), Poly ethylene glycol (PEG) and Montmorillonite (MMT) by solution casting method. The Na+ MMT was modified (protonated) to H+ MMT with ion exchange process. The prepared membranes were characterized by using TGA, FTIR, XRD, Ion Exchange Capacity, Water/Methanol uptake, swelling ratio and proton conductivity. The significant improvements in the hydrolytic stability were observed. In addition, thermal stability of the composite membranes were improved and controlled by the addition of MMT. All the prepared membranes are shown appreciable values of proton conductivity at room temperature with 100% relative humidity. [ABSTRACT FROM AUTHOR]

Nanocomposite membranes based on multiwalled carbon nanotube /SPEEK (sulfonated poly ether ether ketone) have been synthesized via simple solution casting. Prior to use CNT have been purified and grafted with carboxylic acid groups onto its walls by means of sulfuric and nitric acid. Afterwards, amidation of carboxylated CNTs (c-CNT) has been done. Amidated CNT (a-CNT) is then incorporated in SPEEK polymer matrix to synthesize nanocomposite membranes. Physicochemical, structural, thermal and mechanical characterizations are done through the respective techniques. Electric and ionic conductivities have also been evaluated. Composites membranes show the enhanced electrochemical performance with higher electric conductivity. [ABSTRACT FROM AUTHOR]

Mesoporous silica (MCM-41) has been synthesized via sol gel route. Sulfonation of MCM-41 has been done. Synthesized Sulfonated MCM-41 (S-MCM-41) has been incorporated within SPES (sulfonated poly ether sulfone) polymer matrix to prepare composite membranes. Various concentration of S-MCM-41 has been incorporated into SPES i.e. 1, 2, 5, 10 and 20 wt% to synthesize membranes of different wt% of mesoporous silica. FTIR and XRD of MCM-41 and S-MCM-41 were done to confirm the chemical and structural properties. AFM and UTM are used to find out morphology and mechanical properties of the composites. The water uptake and ionic conductivity of the composite membranes increases with MCM content in composite membrane. Mechanical stability of the membrane also found to be increases with MCM content. [ABSTRACT FROM AUTHOR]

In the present study, Zinc oxide (ZnO) nanoparticlewasdirectly incorporated into mixed Polysulfone(PSF) and Poly ethylene glycol (PEG) homogeneous solution to design PSF/PEG/ZnOnano composite membrane to modify surface properties. Prior to this, ZnO nanoparticle was synthesized by precipitation method. The average crystallite size of ZnO nanoparticle is found as 16nm by using XRD analysis. FESEM images have showed that the PSF/PEG/ZnOnano composite membrane has modified porous morphology. The Hydrophilicity of the prepared membrane was also studied using contact angle measurement. It was observed that the incorporation of ZnO was the responsible for the hydrophilic nature of the nano composite membrane. The performance of prepared membrane was evaluated in terms of water permeability by varying applied pressure. The water permeability increased with the increase in pressure which could be attributed toporous nature and hydrophilicity of the membrane. [ABSTRACT FROM AUTHOR]

Present manuscript deals with the synthesis of nanocomposite polymer electrolyte membrane (PEM) based on copper based metal organic framework (Cu-MOF) and sulfonated poly ether sulfone (SPES) for fuel cell application. Prepared material and composite membrane has been analyzed through various techniques. Structural and thermal characterization of prepared material has been carried out through XRD, FTIR and TGA technique. Measurement shows the successful synthesis of MOF and also confirms the thermal stability. Prepared membranes shows good physicochemical properties and good ionic conductivity which can be utilized as PEM for fuel cell application. [ABSTRACT FROM AUTHOR]