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Abstract Background Urethral stricture and reconstruction are one of the thorny difficult problems in the field of urology. The continuous development of tissue engineering and biomaterials has given new therapeutic thinking to this problem. Bacterial cellulose (BC) is an excellent biomaterial due to its accessibility and strong plasticity. Moreover, adipose-derived stem cells (ADSCs) could enhance their wound healing ability through directional modification. Methods First, we used physical drilling and sulfonation in this study to make BC more conducive to cell attachment and degradation. We tested the relevant mechanical properties of these materials. After that, we attached Fibroblast Growth Factor Receptor 2 (FGFR2)-modified ADSCs to the material to construct a urethra for tissue engineering. Afterward, we verified this finding in the male New Zealand rabbit model and carried out immunohistochemical and imaging examinations 1 and 3 months after the operation. At the same time, we detected the potential biological function of FGFR2 by bioinformatics and a cytokine chip. Results The results show that the composite has excellent repairability and that this ability is correlated with angiogenesis. The new composite in this study provides new insight and therapeutic methods for urethral reconstruction. The preliminary mechanism showed that FGFR2 could promote angiogenesis and tissue repair by promoting the secretion of Vascular Endothelial Growth Factor A (VEGFA) from ADSCs. Conclusions Double-modified sulfonated bacterial cellulose scaffolds combined with FGFR2-modified ADSCs provide new sight and treatments for patients with urethral strictures.

Single crystals of a new coordination polymer, {[Zn(2,2'-bipyridine)(H2O)2(1,5-NDS)].2H2O}, where 1,5-NDS is 1,5-naphthalenedisulfonate ion, have been successfully grown under hydrothermal conditions. The as- synthesised coordination polymer was characterised by X-ray Diffraction analysis which shows that the metal centres have been linked by 1,5-NDS linkers and then the structure has extended in a 1D chain. Moreover, the compound was studied using thermogravimetric analysis (TGA) to check its thermal stability and IR spectroscopy. The prepared compound was a good candidate as a precursor to prepare ZnO nanoparticles. ZnO nanoparticles which were achieved after calcinating the compound, were characterized by Scanning Electron Microscopy (SEM) and PXRD. [ABSTRACT FROM AUTHOR]

The study focuses on reactive orange 16 (RO16), a sulfonated dye, and ciprofloxacin (CiP), a fluoroquinolone antibiotic treatment from aquatic surface by adsorption. The functionalized Persea americana seed powder (PASP) was developed by acid hydrolysis technique and investigated for RO16 and CiP removal in batch scale at different concentrations for CiP and RO16, pH (2–8), contact duration and temperature (303–318K). Utilizing a scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDAX), the generated native PASP were assessed for their morphological characteristics. Fourier transform infrared (FTIR) spectroscopy was applied to examine the performing characteristics of PASP. Experimental findings with four kinetic mathematical models allowed the estimation of the process involved in the biosorption. The most effective agreement was explained by the pseudo-second-order model and Sips isotherm (Cip = 34.603 mg/g and RO16 = 30.357 mg/g) at 303K temperature. For Cip Process economics of the biosorbent was done, and it was observed that it was less than the readily market-available activated carbon. • Persea americana -seed biosorbent removed ciprofloxacin and Reactive Orange 16. • Functionalizing the biosorbent's surface enhanced removal efficiency. • Pollutant removal followed Sips isotherm and pseudo-second-order kinetics. • Process economics highlighted cost-effectiveness and agro-waste valorization. [ABSTRACT FROM AUTHOR]

The by-product of the previous transesterification, glycerol was utilised as an acid catalyst precursor for biodiesel production. The crude glycerol was treated through the sulfonation method with sulfuric acid and chlorosulfonic acid in a reflux batch reactor giving solid glycerol-SO3H and glycerol-ClSO3H, respectively. The synthesised acidic glycerol catalysts were characterised by various analytical techniques such as thermalgravimetric analyser (TGA), infrared spectroscopy, surface properties adsorption-desorption by nitrogen gas, ammonia-temperature programmed desorption (NH3-TPD), X-ray diffraction spectroscopy (XRD), elemental composition analysis by energy dispersive spectrometer (EDX) and surface micrographic morphologies by field emission electron microscope (FESEM). Both glycerol-SO3H and glycerol-ClSO3H samples exhibited mesoporous structures with a low surface area of 8.85 mm2/g and 4.71 mm2/g, respectively, supported by the microscopic image of blockage pores. However, the acidity strength for both catalysts was recorded at 3.43 mmol/g and 3.96 mmol/g, which is sufficient for catalysing PFAD biodiesel at the highest yield. The catalytic esterification was optimised at 96.7% and 98.2% with 3 wt.% of catalyst loading, 18:1 of methanol-PFAD molar ratio, 120 °C, and 4 h of reaction. Catalyst reusability was sustained up to 3 reaction cycles due to catalyst deactivation, and the insight investigation of spent catalysts was also performed. [ABSTRACT FROM AUTHOR]

Background: Urethral stricture and reconstruction are one of the thorny difficult problems in the field of urology. The continuous development of tissue engineering and biomaterials has given new therapeutic thinking to this problem. Bacterial cellulose (BC) is an excellent biomaterial due to its accessibility and strong plasticity. Moreover, adipose-derived stem cells (ADSCs) could enhance their wound healing ability through directional modification. Methods: First, we used physical drilling and sulfonation in this study to make BC more conducive to cell attachment and degradation. We tested the relevant mechanical properties of these materials. After that, we attached Fibroblast Growth Factor Receptor 2 (FGFR2)-modified ADSCs to the material to construct a urethra for tissue engineering. Afterward, we verified this finding in the male New Zealand rabbit model and carried out immunohistochemical and imaging examinations 1 and 3 months after the operation. At the same time, we detected the potential biological function of FGFR2 by bioinformatics and a cytokine chip. Results: The results show that the composite has excellent repairability and that this ability is correlated with angiogenesis. The new composite in this study provides new insight and therapeutic methods for urethral reconstruction. The preliminary mechanism showed that FGFR2 could promote angiogenesis and tissue repair by promoting the secretion of Vascular Endothelial Growth Factor A (VEGFA) from ADSCs. Conclusions: Double-modified sulfonated bacterial cellulose scaffolds combined with FGFR2-modified ADSCs provide new sight and treatments for patients with urethral strictures. [ABSTRACT FROM AUTHOR]

Recently, cost-effective ionic polymer metal composite (IPMC) membranes coated with novel metals (viz., Ag, Au, or Pt) have exhibited excellent bending actuation performance, which was electrically stimulated. Herein, we have developed an IPMC membrane of highly cost-effective Kraton (KR) fabricated by incorporating Copper nanoparticles (CuNPs). It was then coated with Pt-metal using a solution casting process. The developed IPMC membrane (KR-CuNPs-Pt) was characterized using Fourier-transform infrared (FTIR) spectroscopy, Transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. Further, ionic exchange capacity (IEC), the proton conductivity (PC), and water uptake/loss studies have also been performed. Actuation performance was measured using the electromechanical techniques. The actuation force of ca. 0.343 mN and displacement of ca. 18 mm at 4 VDC indicate that the developed membrane may serve as an alternative to the highly expensive commercialized IPMC actuators based on perfluorinated polymers. A soft bending actuator in the form of a micro-gripper was also developed. [ABSTRACT FROM AUTHOR]

Sulfonated carbon‐based catalysts (SCC) are favorable heterogeneous acids for acid‐catalyzed reactions including esterification and transesterification for biodiesel production. They are covalently functionalized with SO3H groups via CPhSO3H or CSO3H linkages with special carbon structures. To date, the types of SCC for biodiesel production ranges from biochar (BC), activated carbon (AC), graphene, graphite oxides, multiwalled carbon nanotubes, order mesoporous carbon, and graphitic carbon nitride. Lignocellulosic and biomass wastes are important carbon precursors for low‐cost BC and AC production. This review critically reviews and summarizes the most up‐to‐date research progress in the evolution of SCC for biodiesel production. Systematic discussions and comparisons on the different carbon materials, preparation methods, and sulfonation preparation parameters which directly affect the physicochemical attributes and catalytic performance are provided. The applications and reusability studies of these materials in biodiesel production are also included. Finally, the challenges to be addressed and future prospects of the research direction on the applications of SCC for biodiesel production are discussed. [ABSTRACT FROM AUTHOR]

The by-product of the previous transesterification, glycerol was utilised as an acid catalyst precursor for biodiesel production. The crude glycerol was treated through the sulfonation method with sulfuric acid and chlorosulfonic acid in a reflux batch reactor giving solid glycerol-SO3H and glycerol-ClSO3H, respectively. The synthesised acidic glycerol catalysts were characterised by various analytical techniques such as thermalgravimetric analyser (TGA), infrared spectroscopy, surface properties adsorption-desorption by nitrogen gas, ammonia-temperature programmed desorption (NH3-TPD), X-ray diffraction spectroscopy (XRD), elemental composition analysis by energy dispersive spectrometer (EDX) and surface micrographic morphologies by field emission electron microscope (FESEM). Both glycerol-SO3H and glycerol-ClSO3H samples exhibited mesoporous structures with a low surface area of 8.85 mm2/g and 4.71 mm2/g, respectively, supported by the microscopic image of blockage pores. However, the acidity strength for both catalysts was recorded at 3.43 mmol/g and 3.96 mmol/g, which is sufficient for catalysing PFAD biodiesel at the highest yield. The catalytic esterification was optimised at 96.7% and 98.2% with 3 wt.% of catalyst loading, 18:1 of methanol-PFAD molar ratio, 120 °C, and 4 h of reaction. Catalyst reusability was sustained up to 3 reaction cycles due to catalyst deactivation, and the insight investigation of spent catalysts was also performed.

The main purpose of this study is to produce and generate a solid acid catalyst from biomass with high reactivity that can be used in catalytical reactions such as hydrolysis, and is environmentally friendly and reusable. A biocarbon-based sulfonated catalyst was prepared by the carbonization of palm empty fruit bunches (PEFB), followed by sulfonation. In order to enhance the acidity of the biocarbon, different concentrations of hydroxyethylsulfonic acid were added to the solution during sulfonation at 180o C for 4 h in a Teflon stainless steel autoclave. The H+ ion capacity of the biocarbon-sulfonated acid catalyst (BSC) was increased twofold (3.57 mmol/g) in the presence of 10% of hydroxyethylsulfonic acid and 10% of acrylic acid. X-Ray Fluorescence (XRF) analysis showed that the BC-SO3H contained 38% of S. The original structure of the PEFB after carbonization disintegrated from the fibrous materials onto porous carbon. The crystalline index (CrI) of the PEFB significantly decreased to about 32% and a wide broad peak of a X-Ray Diffraction (XRD) pattern of around 20-30o were observed, which shows that an amorphous biocarbon structure had been identified. Fourier Transform Infra-Red (FT-IR) analysis confirmed that the -SO3H, COOH and -OH functional groups were deposited on the carbon due to specific peaks at around 1180 cm-1, 1724 cm-1 and 3431 cm-1, respectively. Decomposition of the sulfonic groups on the biocarbon-sulfonated solid catalyst was observed from 227.9o C, as it shown by thermal gravimetric analysis (TGA).

Recently, cost-effective ionic polymer metal composite (IPMC) membranes coated with novel metals (viz., Ag, Au, or Pt) have exhibited excellent bending actuation performance, which was electrically stimulated. Herein, we have developed an IPMC membrane of highly cost-effective Kraton (KR) fabricated by incorporating Copper nanoparticles (CuNPs). It was then coated with Pt-metal using a solution casting process. The developed IPMC membrane (KR-CuNPs-Pt) was characterized using Fourier-transform infrared (FTIR) spectroscopy, Transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. Further, ionic exchange capacity (IEC), the proton conductivity (PC), and water uptake/loss studies have also been performed. Actuation performance was measured using the electromechanical techniques. The actuation force of ca. 0.343 mN and displacement of ca. 18 mm at 4 VDC indicate that the developed membrane may serve as an alternative to the highly expensive commercialized IPMC actuators based on perfluorinated polymers. A soft bending actuator in the form of a micro-gripper was also developed.

This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)–phosphotungstic acid (PTA) ionic polymer–metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g−1 and ca. 1.6 mS·cm−1, respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.

This work investigated the application of solid acid HSO3-ZSM-5 zeolite catalyst into corncob-derived xylan conversion to furfural using biphasic solvents. Xylan was extracted from corncob by alkaline treatment, followed by precipitation with methanol and bleaching with hydrogen peroxide. Then, corncob-derived xylan bio-polymer was subject to the combination process of hydrolysis and dehydration using zeolite catalyst and ultrasound pretreatment. The influences of reaction factors including solvent, catalyst dose, temperature and time were studied. Suitable conditions, which provide highest yield of furfural with 89.4% have been established. This HSO3-ZSM-5 zeolite exhibited the high catalytic efficiency for conversion of xylan to furfural, an important and useful intermediates for the chemical industry. Moreover, the catalyst could reuse efficiently with no significant loss of catalytic activity after several recycles. [ABSTRACT FROM AUTHOR]

The investigation of carbonic anhydrase and paraoxonase enzyme inhibition properties of water-soluble zinc and gallium phthalocyanine complexes (1 and 2) are reported for the first time. The binding of p-sulfonylphenoxy moieties to the phthalocyanine structure favors excellent solubilities in water, as well as providing an inhibition effect on carbonic anhydrase (CA) I and II isoenzymes and paraoxonase (PON1) enzyme. According to biological activity results, both complexes inhibited hCA I, hCA II, and PON1. Whereas 1 and 2 showed moderate hCA I and hCA II (off-target cytosolic isoforms) inhibitory activity (Ki values of 26.09 µM and 43.11 µM for hCA I and 30.95 µM and 33.19 µM for hCA II, respectively), they exhibited strong PON1 (associated with high-density lipoprotein [HDL]) inhibitory activity (Ki values of 0.37 µM and 0.27 µM, respectively). The inhibition kinetics were analyzed by Lineweaver-Burk double reciprocal plots. It revealed that 1 and 2 were noncompetitive inhibitors against PON1, hCA I, and hCA II. These complexes can be more advantageous than other synthetic CA and PON inhibitors due to their water solubility. Docking studies were carried out to examine the interactions between hCA I, hCA II, and PON1 inhibitors and metal complexes at a molecular level and to predict binding energies. [ABSTRACT FROM AUTHOR]

A clean, sulfonated, highly adsorptive macroporous monolith was constructed using a carbon dioxide‐in‐water (C/W) high internal phase emulsion template. The random copolymerization of N‐hydroxyethyl acrylamide and sodium styrene sulfonate in the water phase was initiated with persulfate. The chemical composition of the novel sulfonated monolith was confirmed by Fourier transform infrared spectroscopy and energy‐dispersive X‐ray spectroscopy, and the interconnected pore structure was confirmed by scanning electron microscopy (SEM). Results showed that the void sizes were 47–92 μm and that the interconnected pore throats were approximately 10–30 μm. Such a hydrophilic, anionic macroporous material exhibited excellent adsorption properties for cationic dyes. The maximum adsorption capacity of the monolith for methylene blue (MB) and malachite green (MG) reached 1,316 and 2,624 mg/g, respectively, in 500–800 mg/L dye solution at 25°C. Furthermore, the kinetics and thermodynamic parameters of the adsorption process were examined. Experimental data exhibited that adsorption kinetically followed the pseudo‐second‐order model. The removal rates of MG and MB both exceeded 90% after six regenerations. The adsorption mechanism of the adsorbent was demonstrated preliminarily. The dynamic adsorption operation of MB was conducted in a fixed column, and the breakthrough curve data were fitted using the Thomas and bed depth service time models. All these findings indicated the potential industrial applications of adsorptive sulfonated macroporous monolith. [ABSTRACT FROM AUTHOR]

In order to improve the corrosion resistance of zinc-rich epoxy coatings and reduce the amount of zinc used, first, graphene oxide (GO) was modified by sulfonated multiwall carbon nanotubes (SMWCNTs) to obtain the modified graphene oxide (SM-GO). The samples were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and Raman spectroscopy. Then, four kinds of coatings were prepared, namely pure zinc-rich coating (0-ZRC), graphene oxide-based zinc-rich coating (GO-ZRC), sulfonated multiwall carbon nanotube-based zinc-rich coating (SM-ZRC) and SM-GO-based zinc-rich coating (SG-ZRC). The corrosion resistance of the above coatings was studied by open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), a salt spray test, 3D confocal microscope, and electron scanning electron microscope (SEM). The results indicate that GO is successfully non-covalently modified by SMWCNTs, of which the interlayer spacing increases and dispersion is improved. The order of the corrosion resistance is GO-ZRC > SG-ZRC > SM-ZRC > 0-ZRC. The addition of GO, SMWCNTs, and SM-GO increases the shielding effect and increases the electrical connection between Zn particles and metal substrates, which improves the corrosion resistance. However, SMWCNTs and SM-GO also strengthen the galvanic corrosion, which decreases the corrosion resistance to some extent.

The main purpose of this study is to produce and generate a solid acid catalyst from biomass with high reactivity that can be used in catalytical reactions such as hydrolysis, and is environmentally friendly and reusable. A biocarbon-based sulfonated catalyst was prepared by the carbonization of palm empty fruit bunches (PEFB), followed by sulfonation. In order to enhance the acidity of the biocarbon, different concentrations of hydroxyethylsulfonic acid were added to the solution during sulfonation at 180o C for 4 h in a Teflon stainless steel autoclave. The H+ ion capacity of the biocarbon-sulfonated acid catalyst (BSC) was increased twofold (3.57 mmol/g) in the presence of 10% of hydroxyethylsulfonic acid and 10% of acrylic acid. XRay Fluorescence (XRF) analysis showed that the BC-SO3H contained 38% of S. The original structure of the PEFB after carbonization disintegrated from the fibrous materials onto porous carbon. The crystalline index (CrI) of the PEFB significantly decreased to about 32% and a wide broad peak of a X-Ray Diffraction (XRD) pattern of around 20-30o were observed, which shows that an amorphous biocarbon structure had been identified. Fourier Transform Infra-Red (FT-IR) analysis confirmed that the -SO3H, COOH and -OH functional groups were deposited on the carbon due to specific peaks at around 1180 cm-1, 1724 cm-1 and 3431 cm-1, respectively. Decomposition of the sulfonic groups on the biocarbon-sulfonated solid catalyst was observed from 227.9o C, as it shown by thermal gravimetric analysis (TGA). [ABSTRACT FROM AUTHOR]

The main purpose of this study is to produce and generate a solid acid catalyst from biomass with high reactivity that can be used in catalytical reactions such as hydrolysis, and is environmentally friendly and reusable. A biocarbon-based sulfonated catalyst was prepared by the carbonization of palm empty fruit bunches (PEFB), followed by sulfonation. In order to enhance the acidity of the biocarbon, different concentrations of hydroxyethylsulfonic acid were added to the solution during sulfonation at 180o C for 4 h in a Teflon stainless steel autoclave. The H+ ion capacity of the biocarbon-sulfonated acid catalyst (BSC) was increased twofold (3.57 mmol/g) in the presence of 10% of hydroxyethylsulfonic acid and 10% of acrylic acid. X-Ray Fluorescence (XRF) analysis showed that the BC-SO3H contained 38% of S. The original structure of the PEFB after carbonization disintegrated from the fibrous materials onto porous carbon. The crystalline index (CrI) of the PEFB significantly decreased to about 32% and a wide broad peak of a X-Ray Diffraction (XRD) pattern of around 20-30o were observed, which shows that an amorphous biocarbon structure had been identified. Fourier Transform Infra-Red (FT-IR) analysis confirmed that the -SO3H, COOH and -OH functional groups were deposited on the carbon due to specific peaks at around 1180 cm-1, 1724 cm-1 and 3431 cm-1, respectively. Decomposition of the sulfonic groups on the biocarbon-sulfonated solid catalyst was observed from 227.9o C, as it shown by thermal gravimetric analysis (TGA). [ABSTRACT FROM AUTHOR]

Cerium oxide (CeO2) is a rare earth metal oxide that has high oxygen storage capacity at low temperature. In order to enhance this capacity, as well as its thermal stability, it is necessary to combine CeO2 with zirconium oxide (ZrO2). This work focuses on the synthesis of cerium-zirconium oxides by hydrothermal and solvothermal treatment at low temperature to obtain ones suitable for catalyst applications. The possibility of the application of ceria-zirconia oxide to the delignification reaction was investigated. The experiments were conducted at a constant pressure of 5 MPa, constant temperature of 150oC, and constant synthesis time of 2 h, in an autoclave reactor made of SUS 316 with an internal volume of 100 mL. Precursor was prepared from Ce(NO3)3 and ZrO(NO3)2 at 0.06 M concentration, dissolved in various solvents. The solvents used were water, water/ethanol (70:30 vol/vol), and water/ethylene glycol (70:30 vol/vol). After hydrothermal and solvothermal synthesis, the colloid products were dried at 60oC for 6 h and then calcined at 500oC for 6 h. The characterizations of the particle products were analyzed using SEM and XRD. Furthermore, these products were used for the hydrothermal delignification process of wood biomass. The addition of ceria-zirconia particles dramatically increased the percentage of lignin removal from rapeseed wood up to 97.58%. Based on the results, ceria-zirconia oxide particles are effective for the pre-treatment of wood biomass in bio-refinery applications. Moreover, ceria-zirconia oxides may reduce the use of chemical compounds in the delignification process. [ABSTRACT FROM AUTHOR]

Abstract In the present study, the sulfonated electroactive polyurea (S-EPU) was first prepared and characterized, applied as an anticorrosion coating. The electroactive oligomer sulfonated amine-capped aniline trimer (S-ACAT) was synthesized by oxidative coupling reaction, followed by characterization using Fourier-transform infrared (FTIR) and mass spectroscopy (MS). For the preparation of sulfonated electroactive polyurea (S-EPU), isophorone diisocyanate (IPDI) was reacted with poly(tetramethylene ether) glycol (PTMEG) in the presence of a specific amount of diamine S-ACAT. The success of the S-EPU was confirmed through FTIR and GPC. After that the redox capability of as-prepared S-EPU was confirmed by CV studies. Chemical oxidization of S-EPU, carried out through the introduction of trace amount of ammonium persulfate, was monitored by UV-VIS spectroscopy. The electrochemical corrosion of the electroactive polymer-coated cold-rolled steel (CRS) electrode, in neutral, acidic and alkaline conditions, were measured and compared. As compared to non-electroactive polyurea (N-EPU), results showed enhanced corrosion protection of the S-EPU coating and electroactive polyurea (EPU) coating, owing to their redox capability that induces the formation of densely passive metal oxide layer (e.g. , Fe 2 O 3 and Fe 3 O 4). The densely metal oxide layers induced by S-EPU/EPU coatings were further confirmed by Raman spectroscopy, SEM and ESCA. Moreover, the S-EPU coating exhibited better anticorrosion performance than that of EPU coating which could be attributed to the higher electro-catalytic property of S-EPU coating upon CRS electrode, causing the formation of more densely metal oxide layers to shelter the underlying metal substrate. Graphical abstract The S-EPU reveals great redox ability, and inducing the formation of densely passive metal oxide layer when coating on CRS. By electrochemical corrosion measurements, S-EPU has good corrosion protection ability. Image 1 Highlights • Sulfonated amino-capped aniline trimer was synthesized successful. • Compounds with sulfonated groups show better redox ability than those without. • The S-EPU has good corrosion protection ability, redox ability and thermal stability. [ABSTRACT FROM AUTHOR]

It is important to emphasize that the adjustment of an organic–inorganic interfacial chemical environment plays an important role during the separation performance of composite materials. In this paper, a series of hybrid membranes were prepared by blending polyvinyl alcohol (PVA) solution and sulfonated nano-TiO2 (SNT) suspension. The effects of different interfacial chemical surroundings on ions transfer were explored by regulating the dosage content of SNT. The as-prepared membranes exhibited high thermal and mechanical stability, with initial decomposition temperatures of 220–253 °C, tensile strengths of 31.5–53.4 MPa, and elongations at break of 74.5–146.0%. The membranes possessed moderate water uptake (WR) values of 90.9–101.7% and acceptable alkali resistances (swelling degrees were 187.2–206.5% and weight losses were 10.0–20.8%). The as-prepared membranes were used for the alkali recovery of a NaOH/Na2WO4 system via the diffusion dialysis process successfully. The results showed that the dialysis coefficients of OH− (UOH) were in a range of 0.013–0.022 m/h, and separate factors (S) were in an acceptable range of 22–33. Sulfonic groups in the interfacial regions and –OH in the PVA main chains were both deemed to play corporate roles during the transport of Na+ and OH−.

[Display omitted] • Naturally sulfonated porous carbon (SPC) from sugarcane bagasse. • Fenton catalytic reaction enhancement with the support of Fe 3 O 4 -SPC. • Remarkable catalytic efficiency within 5 consecutive cycles. In this study, the magnetic ferric oxide-sulfonated porous carbon materials (Fe 3 O 4 -SPC) were fabricated using the magnetic ferric oxide (Fe 3 O 4) nanoparticles via the sulfonation process with sugarcane bagasse as a main cellulose source. The characterization revealed that the spherical shape of Fe 3 O 4 nanoparticles decorated on lamellar porous carbon sheet with uniform size less than 100 nm. Meanwhile, the catalytic assessment on the degradation of methylene blue via the Fenton reaction showed the ratio of Fe 3 O 4 :SPC = 1:2 obtaining the efficiency of 95% after 45 min. Moreover, the material had high reusability, retaining over 95% after 5 consecutive cycles. [ABSTRACT FROM AUTHOR]

Abstract Chrome tannage is the main tanning method because of its excellent hydrothermal stability and physical performances. However, the chromium absorption is limited, so the emissions of solid wastes can bring many environmental issues and human health risks. Therefore, a novel chrome-free tanning agent based on a water-soluble calixarene has been attempted. Water-soluble calixarene is a chemical with a unique molecular structure, thermal stability and high chemical stability, it contains a lot of more active coordination of phenolic hydroxyl. In this work, tetraphenyl calix [4]resorcinarene (TC4R) was synthesized with one-step process, and then was sulfonated by concentrated sulfuric acid, which obtained the sulfonated tetraphenyl calix [4]resorcinarene (STC4R). The chemical structure of the TC4R and STC4R were detected by IR and H-NMR. Then STC4R was added to the tanning process as an experimental process and 6% conventional chrome tannage was added to tanning as control. The result shows that the Ts of tanned leather is 77.2 °C using 10% STC4R at final pH 4.0. SEM analyses show that collagen fibers have been dispersed, STC4R makes the fiber loosen and the fullness is increased. FT-IR shows that the hydrogen bond is formed between phenol hydroxyl of sulfonated calixarenes and amino of collagen in the tanning process. At the same time, STC4R does not enter the micro fibrils within the collagen, so three helix structures are not damaged and consistent with AFM. [ABSTRACT FROM AUTHOR]

Sulfonated polybenzothiazoles were synthesized by polycondensation of 6-sulfonate-1,4-naphthalene dicarboxylic acid, 2,5-diamino-1,4-benzenedithiol dihydrochloride and either 1,4-naphthalene dicarboxylic acid or 2,2-bis(4-carboxyphenyl) hexafluoropropane. The two series are denoted sPBT-NA and sPBT-6F, respectively. While the sPBT-NA series are insoluble in common solvents, the sPBT-6F series are soluble due to the incorporation of hexafluoroisopropylidene moieties, which impart more chain flexibility rather than disrupting the regular packing of the polymer main chain. The sPBT-6F series exhibited high proton conductivity, high thermal and oxidative stability, good mechanical properties and appropriate water uptake and dimensional swelling behavior. For example, the proton conductivity of sPBT-6F90 was much higher than that of Nafion 117, and the proton conductivity of sPBT-6F80, sPBT-6F85 and sPBT-6F95 is also as high as that of Nafion 117. The combined properties of the present sulfonated polybenzothiazoles are commendable for proton exchange membranes. [ABSTRACT FROM AUTHOR]

Core-shell structured conducting polyaniline (PANI)-coated polystyrene (PS) composite nanospherical particles were synthesized and assessed as a candidate for electrorheological (ER) materials. Monodisperse PS nanospheres were initially synthesized by a dispersion polymerization process and their surface was modified using concentrated sulfuric acid. This allowed the aniline monomer to be adsorbed easily on the sulfonated PS nanosphere and polymerized further by forming a PS/PANI nanosphere. The ER performance of their suspension dispersed in silicone oil was examined using a rotational rheometer under a variety of electric field strengths. The Bingham fluid model was used to analyze their flow curves to understand the interrelation between shear stress and shear rate. The relationship between the yield stress and electric field strength showed a slope of 2.0 following a polarization model. The dielectric spectra showed a good correlation with the ER performance of the ER fluid. [ABSTRACT FROM AUTHOR]

In this short review, we discuss the colloidal microstructure of sulfonated cellulose nanocrystal (CNC) suspensions and connect to their rheological behavior in the presence of electrolyte, by changing its surface chemistry and also in dilute water soluble polymer solutions. Presence of electrolyte has a significant effect depending both on the concentrations of CNC and electrolyte. The salt presence on the microstructure of CNC suspensions were successfully explained by DLVO theory. Even within the dilute concentration regime (< 0.5 vol%), CNC particles can form gels either by adding high concentration of electrolyte or low concentration (around overlapping concentration) of non-adsorbing polymer. Addition of water soluble polymers may cause depletion of CNC if the polymer is not adsorbing. It is believed that the depletion flocculation is the case for the effects of carboxymethyl cellulose (CMC) polymer chains in CNC suspensions and cause significant gelling. [ABSTRACT FROM AUTHOR]

To improve the dimensional stability and methanol resistance, a novel phthalonitrile-terminated sulfonated poly(arylene ether nitrile)s (SPENs) to prepare cross-linked membranes for direct methanol fuel cells (DMFCs) application has been successfully implemented. Compared with SPENs, cross-linked membranes exhibited lower water uptake, swelling ratio, and methanol permeability coefficient. For example, the water uptake and swelling ratio of SPEN-70 were 50.3 wt.% and 17.0% as the values of cross-linked sulfonated poly(arylene ether nitrile)s (CSPEN)-70 were merely 15.4 wt.% and 3.2% at 20 °C. The methanol permeability of SPEN-70 was 6.7 × 10 cm s as the values of CSPEN-70 were merely 1.4 × 10 cm s, which were all much lower than that of Nafion 117 (1.41 × 10 cm s) as expected. Although the proton conductivity of CSPEN slightly decreased by the introduction of cross-linked structure, it possessed higher selectivity than the SPEN and Nafion 117 due to their lower methanol permeability. The cross-linked SPEN-50 (CSPEN-50) membrane exhibited the highest selectivity, which about 30.7 times higher compared with that of Nafion 117. [ABSTRACT FROM AUTHOR]

[Display omitted] • Compatibility of electrode/electrolyte was improved using sulfonated PVDF binder. • The sulfonated copolymer binders showed suitable performance for long-life batteries. • Lower concentration polarization occurred in electrodes containing sulfonated binders. In today's market, lithium-ion batteries are proving to be the most promising and effective rechargeable batteries. In the development of active materials with high energy density for batteries, the design of binders is a bottleneck technology, which produces an interconnected electrode structure. In this study, for developing lithium-ion batteries with high efficiency, the sulfonated copolymer was employed as an effective binder. In order to improve the performance of poly(vinylidene fluoride) (PVDF) as a binder for lithium-ion batteries (LIBs), sulfonated PVDF copolymer was prepared in this study using the atom transfer radical polymerization (ATRP) process. The influence of sulfonated PVDF binder on the electrochemical performances of LIBs was assessed using charge and discharge measurements, cycling performance up to 300 cycles, cycling voltammetry (CV), and electrochemical impedance spectroscopy (EIS) analysis. The investigation indicated decreased concentration polarization and improved lithiation and delithiation kinetics at high number of charge/discharge cycles for LiFePO 4 electrodes with sulfonated PVDF binders. The discharge capacity after 300 cycles was 90 mAh g−1 with a capacity retention of 100% at 1C. As a result, the copolymer synthesized in this paper can be utilized to design next-generation polymer binders for high-efficiency LIBs. [ABSTRACT FROM AUTHOR]

Sulfonic acid groups were introduced onto graphene oxide (GO) via sulfonation reaction to prepare sulfonated graphene oxide (SG). Then, zincoxysulfide–SG composite photocatalysts were prepared by mixing SG and zincoxysulfide (ZnS 1−x O x ) nanoparticles. The morphology, crystalline properties, bandgap, and photocatalytic H 2 production activity of these photocatalysts were investigated by FESEM, XRD, Mott–Schottky plots, and H 2 production tests. The photocatalytic H 2 production rates of Ce-doped zincoxysulfide–SG photocatalyst under UV and visible light irradiation reach 2100 and 700 μmol g −1 h −1 , respectively. The improved H 2 evolution activity of Ce-doped zincoxysulfide–SG composite photocatalysts can be attributed to the strong interaction between SG sheets and zincoxysulfide nanoparticles. By introducing sulfonated graphene oxide and Ce-doping, SG–zincoxysulfide photocatalysts exhibit stable and high photocatalytic H 2 production activity, resulting from increased specific surface area, efficient charge separation, decreased bandgap and enhanced light absorption. After 3 cycles, the photocatalytic activity of recycled C2ZG2 photocatalyst remains at about 93.8% of its original activity. [ABSTRACT FROM AUTHOR]

A series of sulfonated polybenzothiazoles (sPBT-E) were synthesized by direct polycondensation of 3,3′-disulfonate-4,4′-dicarboxylbiphenyl (DSBP), 4,4′-dicarboxylic diphenyl ether (DCPE) and 2,5-diamino-1,4-benzenedithiol dihydrochloride (DABDT) in polyphosphoric acid (PPA). The sPBT-E series showed considerable solubility in common organic solvents due to the presence of flexible ether groups in the polymer backbone. Sulfonated graphene oxide (SGO) with different loadings (1, 2, 3, and 4 wt%) was doped into the sPBT-E matrix with the sulfonated monomer ratio of 62.5% to prepare composite PEMs (denoted as sPBT-E62.5/SGO) for the first time. sPBT-E membranes with different sulfonated monomer ratios (55, 57.5, 60, and 62.5) were also prepared for comparison. sPBT-E and sPBT-E62.5/SGO series membranes exhibit excellent dimensional stability, appropriate water uptake, high thermal stabilities, and mechanical properties. Additionally, SGO can provide additional ion-transporting sites (resulting in continuous proton transfer channels) to enhance proton conduction of the sPBT-E62.5/SGO membranes. Therefore, the proton conductivity and power density of sPBT-E62.5/SGO3 were up to 0.139 S cm−1 and 519.9 mW cm−2 at 80 °C and 100% RH, which are superior to sPBT-E series and Nafion 212 (0.133 S cm−1, 413.2 mW cm−2). After 20 h continuous operation, the output voltage of sPBT-E62.5/SGO3 only decreased by 13.2%, which is better than sPBT-E62.5 (22.7%). Hence, the sPBT-E62.5/SGO3 membrane exhibits excellent potential as an alternative PEM for PEMFCs. [Display omitted] • Dicarboxylic acid monomers were incorporated into sulfonated polybenzothiazoles (sPBT-E). • SGO fillers were doped into sPBT-E62.5 to prepare a high-performance composite PEM. • sPBT-E62.5/SGO membranes showed excellent properties comparable to sPBT-E membranes. • sPBT-E62.5/SGO3 exhibited high proton conductivity (0.139 S cm−1) and power density (519.9 mW cm−2) at 80 °C and 100% RH. [ABSTRACT FROM AUTHOR]

Utilisation of lignocellulosic agricultural waste biomass could provide a carbon net zero alternative for production of valuable chemicals. However, the progress is hindered because there's no catalyst to carry out a selective and efficient conversion process. In this study a new promising catalyst for this challenging conversion is reported. It is prepared by sulfonation of activated carbon followed by the impregnation of tin (Sn). The catalyst has been characterized by NH 3 -TPD, FTIR, XRF and N 2 physisorption. The catalyst was tested at 120 °C for the conversion of model carbohydrate mixtures prepared in the laboratory and real biomass mixtures of apple fruit biomass waste. The catalytic performance for the conversion of a model carbohydrate mixture resulted in a 5-hydroxymethylfurfural (5-HMF) yield of 30% in 80 min. On the other hand, catalytic testing of real apple pomace biomass showed a 5-HMF yield of 24% in 80 min. The Sn catalyst was also shown to maintain the 5-HMF yield in recycle experiments using a model carbohydrate mixture. Conversely, stability was lower when the Sn catalyst was tested in real apple pomace mixture, which is likely due to the presence of other impurities. • Low temperature (120 °C) conversion of carbohydrates rich agricultural apple fruit waste to 5-HMF. • Cheap and easy method for the preparation of tin doped sulfonated carbon catalysts. • Characterization revealed that the Sn-Fn-Ac catalyst contained both Lewis and Brønsted acidity. • Sn-Fn-AC showed for glucose, fructose and sucrose mixtures 30% 5-HMF yield at conversion of 60%. • Catalytic conversion of carbohydrate mixtures from biomass yielded 24% of 5-HMF respectively. [ABSTRACT FROM AUTHOR]

Sulfonated polyether ether ketone (SPEEK) has been widely investigated in proton exchange membrane fuel cells (PEMFCs) due to its excellent thermal stability, chemical stability, and low cost compared with Nafion. However, excessive degree of sulfonation will easily lead to the decrease in thermal stabilities and mechanical properties of SPEEK membranes, which limits the enhancement of proton conductivity. In this work, a series of Schiff-base networks (SNWs) with different contents are in situ synthesized in the SPEEK membrane by a Schiff-base co-condensation reaction, and then, the composite membranes are soaked in sulfonic acid for further improvement of proton conductivity. The highest doping amount of the SNW filler in SPEEK can reach 20 wt %. High loading and low leaching rate of H 2 SO 4 are easily achieved owing to the similar size between sulfuric acid molecules and micropores in SNW. Moreover, abundant amino and imine groups in SNW networks contribute to the anchoring of H 2 SO 4 into the pores by acid-base interactions. The proton conductivity of the SPEEK/S-SNW-15 composite membrane can reach 115.53 mS cm -1 at 80 °C and 100% RH. Meanwhile, the composite membrane also exhibits satisfied stability and mechanical property.

Sulfonated cellulose nanowhiskers (sulfonated CNWs), a kind of needle-like colloidal particles, could be obtained through sulfuric acid hydrolysis of microcrystal cellulose extracted from sisal fibers. Here, stable Pickering emulsions were prepared using the sulfonated CNWs as a stabilizer. The effects of the sulfonated CNW concentration in aqueous phase, volume ratio of water to oil, oil type, and the pH value on the stability, type, and morphology of these emulsions were investigated. The average droplet size decreases with increasing sulfonated CNW concentration and volume ratio of water to oil. Many types of oil phase were stabilized by sulfonated CNWs to form stable oil-in-water (o/w) Pickering emulsion only by adjusting the pH value of water phase. In addition, poly(methyl methacrylate)PMMA/sulfnated CNW composite microspheres were fabricated by solvent volatilization of the as-prepared Pickering emulsion. Confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM) studies confirmed that sulfonated CNWs adsorbed on the surface of the PMMA microparticles. With the interesting renewability and biodegradability of the sulfonated cellulose nanowhisker, these PMMA@sulfonated CNW composite microsphere could find great potential application in food, cosmetics, drug delivery, and biological tissue engineering, etc. [ABSTRACT FROM AUTHOR]

A novel series of sulfonated 4-phenyl phthalazinone-based polybenzimidazoles (SPPBIs) were synthesized by solution polycondensation of 3,3′-diaminobenzidine (DAB), 4-(4-(4-(4-carboxyphenoxy)phenyl)-1-oxophthalazin-2(1H)-yl) benzoic acid (CPPBC) and 5-sulfoisophthalic acid monosodium salt (SIPN) in polyphosphoric acid (PPA). Their chemical structures were characterized by NMR, FT-IR and wide angle X-ray diffraction (WAXD). The inherent viscosities in 98wt.% H2SO4 were in the range of 1.49–1.78dL/g. The SPPBIs exhibited good solubility in polar aprotic organic solvents, such as N-methyl-2-pyrolidinone (NMP), N,N-dimethylacetamide (DMAc) and dimethyl sulfoxide (DMSO). The membranes were prepared by solution casting technique using DMSO as solvent. The SPPBI polymers showed excellent thermal stability, and their membranes displayed low water uptake, low swelling ratio, good mechanical properties and excellent resistance to oxidation. The SPPBI membranes had unexpected low methanol permeability (5.46×10−10–1.27×10−9 cm2/s). They exhibited high conductivities in the range of 4.8×10−3 S/cm to 1.3×10−2 S/cm at 80°C and from 2.3×10−3 S/cm to 8.5×10−3 S/cm at 20°C. [ABSTRACT FROM AUTHOR]

Abstract: A series of sulfonated poly(phthalazinone ether phosphine oxide)s with disulfonated moieties (dsPPEPO) were synthesized. Sulfonated poly(phthalazinone ether phosphine oxide)s with mono-sulfonated moieties (msPPEPO) were also prepared for comparative study. These two series of polymers represented two kinds of distribution modes of sulfonic acid side groups. The distribution mode of the sulfonic acid side groups within membranes could remarkably change their microstructure. As a result, dsPPEPO exhibited better dimensional and oxidative stability as compared to msPPEPO on condition of equal sulfonation degree. Moreover, the as-synthesized dsPPEPO showed enhanced proton conductivity further by increasing sulfonation degree while remaining excellent dimensional and oxidative stability. Therefore, the resulting membranes displayed excellent overall properties. For example, the dsPPEPO membrane with a sulfonation degree of 110% presented a lower swelling and much higher proton conductivity than those of Nafion 117. Its oxidative stability was also comparable to the highly durable aromatic PEMs. [Copyright &y& Elsevier]

Abstract: Ion pairs consisting of N-substituted derivatives of 1,3,5-triaza-7-phosphaadamantane (pta-R; R=benzyl, butyl, hexyl) as cations and monosulfonated triphenylphosphine (mtppms) as anion were synthesized and characterized (including X-ray diffraction, too). These ion pairs act as bidentate phosphorus ligands in reactions with [(η6-C10H14)RuCl2]2, yielding mononuclear or dinuclear half sandwich Ru(II) complexes. Bisphosphine 3 of good water-solubility was synthesized in reaction of pta with 1,4-bis(chloromethyl)benzene and used for the synthesis of the water-soluble dinuclear complex [{(η6-C10H14)RuCl2}2(μ-3)]Cl2. [Copyright &y& Elsevier]

Abstract: Graphene oxide has received world-wide attention due to its exceptional physicochemical properties. Herein, a sulfonated magnetic graphene oxide composite (SMGO) was synthesized from graphene oxide and was used as adsorbent for removing Cu(II) ions from aqueous solution. The composite was characterized by TEM, EDS, particles size, BET, TG-DTA, FT-IR, and Raman. It can be separated and recovered easily using magnetic separation technology. The effects of operating parameters such as pH, Cu(II) concentration and temperature on the Cu(II) adsorption were investigated by using a response surface methodology (RSM). Optimum Cu(II) uptake of 62.73mgg−1 was achieved at pH 4.68, Cu(II) concentrations 73.71mgL−1, and temperature 50°C. The adsorption process can be well described by the pseudo-second order kinetic model. The experimental data of isotherm followed the Langmuir isotherm model. Moreover, the thermodynamic parameters calculated from the temperature-dependent isotherms indicated that the adsorption reaction was an endothermic and spontaneous process. All results indicate that the SMGO is a promising adsorbent for the efficient removal of copper ions from wastewater. [Copyright &y& Elsevier]

Abstract: Soluble sulfonated polybenzothiazoles (sPBTs) were achieved by incorporation of flexible ether groups to the backbone for the first time. The corresponding hexafluoroisopropylidene-containing sPBTs were also prepared by direct polycondensation for comparison. Both series of sPBTs could be cast into homogeneous membranes and showed high thermal and oxidative stability as well as excellent mechanical properties. Furthermore, they also exhibited high proton conductivity and outstanding dimensional stability. For example, they displayed a proton conductivity of 0.11–0.13S/cm at 80°C, but only exhibited an in-plane swelling of 14–15% and a through-plane swelling of 7.1–30% even at 98°C. Interestingly, the swelling in the plane and thickness direction presented no obvious change with increasing temperature. This is because sPBTs possess strong intermolecular interactions, which was verified by dynamic mechanical analysis. Both series of sPBTs are a promising material for proton exchange membranes. [Copyright &y& Elsevier]

Sulfonated copolyanilines (SPANs), SPAN-40 and SPAN-75, were prepared and applied in this tissue engineering study. SPAN scaffolds (SPANs) and control group polyaniline (PANI) were synthesized by performing oxidative polymerization. To further research the effects of neuron regeneration, PC12 cells were cultured on as-prepared PANI and SPANs with laminin (La) treatment under electrical stimulation. The effects on PC12 cell differentiation were investigated by controlling the amount of sulfonated groups (-SO 3 H) in the SPAN chain, the electrical stimulation voltage, and the presence or absence of La coating. The adhesion and proliferation of cells increased with the degree of sulfonation; La and electrical stimulation further promoted neuronal cell differentiation as increased neurite length was demonstrated in the micrograph analyses. In summary, the sulfonated copolyaniline coated with La had the best effect on neuronal differentiation under electrical stimulation, suggesting its potential as a substrate for nerve tissue engineering.

This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)-phosphotungstic acid (PTA) ionic polymer-metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g -1 and ca. 1.6 mS·cm -1 , respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.

A series of poly(arylene ether)s with biphenyl units and pendant sulfonated phenylsulfonyl groups was prepared via nucleophilic aromatic substitution reactions of varying ratios of 3,5-difluoro-3′-sulfonated diphenylsulfone and 4,4′-difluorodiphenylsulfone with 4,4′-biphenol. As such, the sulfonic acid moieties reside in the meta position of a pendant, electron-poor phenylsulfonyl group. Mechanically robust proton-exchange membranes with ion-exchange capacities (IEC) ranging from 0.91 to 2.05 meq g−1 were cast from dimethylacetamide. The thermal stability of the membranes was evaluated via thermogravimetric analysis and the 5% weight losses were found to be in excess of 330 °C in air. The glass transition temperatures were determined, via differential scanning calorimetry, to range from a low of 148 to a high of 209 °C at IEC values of 0.91 and 1.79 meq g−1, respectively. The copolymer membranes reached proton conductivities as high as 142 mS cm−1 under 100% relative humidity, with relatively low water uptake values (8-32 wt%). Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Abstract: Two series of sulfonated polybenzothiazoles were synthesized by polycondensation of 2,5-diamino-1,4-benzenedithiol dihydrochloride and 3,3′-disulfonate-4,4′-dicarboxylbiphenyl with 4,4′-dicarboxylbiphenyl or 2,2-bis(4-carboxyphenyl) hexafluoropropane, which were termed as sPBT-DP and sPBT-BP, respectively. The first series is insoluble in common polar solvents because of its rigid structure. In contrast, the sPBT-BP series are soluble in DMSO and NMP, due to the flexible hexafluoroisopropylidene moieties in the backbone. Thus they could be cast into homogeneous membrane and evaluated as proton exchange membranes. The studies illustrated that they showed high thermal and oxidative stability as well as excellent mechanical properties. Moreover, they exhibited high proton conductivity and outstanding dimensional stability. For example, sPBT-BP57.5 displayed a proton conductivity of 0.094 S/cm and an in-plane swelling of 9.7% as well as a through-plane swelling of 35% at 80 °C. The sPBT-BP ionomers are a promising material for proton exchange membranes. [Copyright &y& Elsevier]

Abstract: Sulfonated poly(arylene ether)s with high content of phosphine oxide moieties were achieved by polycondensation of bis(4-hydroxyphenyl)phenyl phosphine oxide with sulfonated bis(4-fluorodiphenyl)phenyl phosphine oxide and bis(4-fluorophenyl)phenyl phosphine oxide (or decafluorobiphenyl) for the first time. The high content phosphine-oxide moieties are expected to improve the oxidative stability of membranes, while the decafluorobiphenyl units were used to depress the swelling. The studies illustrated that all these membranes exhibited outstanding oxidative stability because of high content phosphine oxide moieties. On the other hand, the membranes with decafluorobiphenyl moieties (sPEPOF) displayed low swelling. This originates from these hydrophobic groups because they facilitated the membranes to form narrow ionic clusters. In summary, the sPEPOF membranes exhibited excellent overall properties. For instance, the sPEPOF membrane with 80% sulfonation degree displayed a proton conductivity of 0.077S/cm as well as a swelling of 12% at 80°C. It also exhibited outstanding oxidative stability and high thermal stability. [Copyright &y& Elsevier]

A series of block sulfonated poly(arylene ether ketone) (SPAEK) copolymers with different block lengths and ionic contents were synthesized by a two-stage process. The morphology of these block SPAEK copolymers was investigated by various methods, such as differential scanning calorimetry (DSC), transmission electron microscope (TEM), and small angle X-ray scattering (SAXS). Dark colored ionic domains of hundreds of nanometers spreading as a cloud-like belt were observed in TEM images. The sizes of the ionic domains as a function of block copolymer composition were determined from SAXS curves. The results for the evolution of ionic domains revealed that the block copolymers exhibited more clearly phase-separated microstructure with increasing ionic contents and hydrophobic sequence lengths. Proton conductivity is closely related to the microstructure, especially the presence of large interconnected ionic domains or ionic channels. Block SPAEK membranes have interconnected ionic clusters to provide continuous hydrophilic channels, resulting in higher proton conductivity. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Poly (vinyl alcohol) was sulfonated and subsequently cross-linked by a thermal curing reaction with dual cross-linkers to prepare membranes for direct methanol fuel cells. Sulfonated poly (vinyl) alcohol (SPVA) with a high degree of sulfonation was synthesized from 4-Formylbenzene-1,3-disulfonic acid disodium salt hydrate via an acetalization reaction with PVA. Various masses of the cross-linking agents 1,3-bis(3-glycidyloxypropyl) tetramethyldisiloxane and 4,4′-oxydiphthalic anhydride were polymerized with SPVA to facilitate manipulation of the properties of the membranes. Notably, the SPVA3 showed excellent proton conductivity (cf.  = 0.218 S cm−1 at 70 °C and Nafion 117 = 0.127 S cm−1), and low methanol permeability (around one half of that Nafion 117). These results suggest that the cross-linked SPVA membranes hold promise as potential proton exchange membranes and given their high proton conductivity and low methanol permeability they may offer advantages when used in direct methanol fuel cells (DMFCs) applications. [Copyright &y& Elsevier]

Abstract: A series of novel hybrid membranes based on sulfonated poly(arylene ether ketone)s (SNPAEKs), polysiloxane (KH-560) and sulfonated curing agent (BDSA) has been prepared by sol–gel and cross-linking reaction for direct methanol fuel cells (DMFCs). All the hybrid membranes (SKB-xx) show high thermal properties and improved oxidative stability compared with the pristine SNPAEK membrane. The sulfonated cross-linked polysiloxanes networks in the hybrid membranes enhance the mechanical properties and reduce the swelling ratio. The swelling ratio of SKB-20 is 22%, which is much lower than that of the pristine SNPAEK (37%) at 80°C. Meanwhile, SKB-xx membranes with greatly reduced methanol permeabilities show comparative proton conductivities to pristine SNPAEK membranes. Notably, the proton conductivities of SKB-5 and SKB-10 reach to 0.192Scm−1 and 0.179Scm−1 at 80°C, respectively, which are even higher than the 0.175Scm−1 of SNPAEK. [Copyright &y& Elsevier]