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Volatile organic compounds (VOCs) are considered to be the main cause of air pollution and should be controlled strictly. Vacuum ultraviolet combined with cerium (Ce)-doped ZnO as the catalyst was investigated for the removal of para-xylene (p-xylene). Based on scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction analysis, the particle size decreased after cerium in the form of Ce3+ and Ce4+ was doped into the ZnO crystal structure. An improved photocatalytic activity (higher p-xylene removal efficiency) was obtained at 0.96% Ce doping, 351 °C calcination temperature, and 339 min calcination duration. Based on the investigation of process parameters, the removal efficiency of p-xylene reached 100% with an initial concentration of 150 mg m−3, a relative humidity of 50%, and a residence time of 60 s. The ozone utilization extent was 96%, suggesting that the remaining ozone after the photocatalysis of p-xylene could be well controlled. Four different kinetic rate equations were used, suggesting that p-xylene and water molecules competed for the same active site. Mechanism analysis suggested that four types of oxidation contributed jointly to the removal of p-xylene and they followed this order: oxidation by the reactive species (RS, mainly ˙OH, O3 and O(1D)) > oxidation by the synergistic interactions among photolysis, RS and h+ > transformation by direct photolysis > oxidation by h+.

Fabrication of superhydrophobic cotton fabrics commonly suffers from disadvantages such as extensive usage of toxic and expensive fluorinated adhesives, tedious and time-consuming treatment processes, poor durability and compromised mechanical properties. Herein, this work offers a one-step approach for fabricating eco-friendly, fluorine-free, flexible and robust functional cotton fabrics by immersion in composite coatings containing polydimethylsiloxane (PDMS) and calcite particles. Results demonstrate that the PDMS/calcite coatings not only enhance mechanical properties of cotton fabrics, but also impart cotton fabrics with excellent superhydrophobic and tunable comfort properties in comparison with the reference materials. Notably, the cotton fabrics treated with the PDMS/calcite coatings also show excellent oil/water separation efficiency of up to 99% after 10 cycles, robust water laundering stability and self-cleaning ability. Therefore, this novel straightforward, cost-efficient, eco-friendly and durable PDMS/calcite composite coating for cotton fabric has great potential in diverse applications including self-cleaning apparel, water-proof wall covering and continuous oil clean-up.

An asymmetric aqueous electric double-layer capacitor is presented, which consists of two activated carbon electrodes, a compact Janus membrane with sulfonated polystyrene and quaternized polystyrene, aqueous acidic and alkaline electrolyte solutions. The carbon-based aqueous supercapacitor can not only run at a high cell voltage of 2.2 V, but also deliver a specific energy of 20.06 Wh kg−1. Moreover, such a supercapacitor with specific energy of 40–50 Wh kg−1 can be predicted after further optimization.

It is challenging to fabricate a starch derivative with a plasticizing effect and good dispersion in a poly(lactic acid) matrix to achieve desirable performance. In this study, self-suspended starch fluids composed of modified granules as the core and polyethylene glycol-substituted tertiary amines as the shell were first fabricated via a combined carboxymethylation and acylation reaction. The as-prepared starch fluids exhibited liquid-like behavior and had semiconductor electric conductivity (4.91 × 10−5 S/cm) at room temperature without a solvent. The modulus of starch fluids was clearly reduced under the heating process and exhibited its initial flow properties upon cooling, displaying thermo-reversible behavior. The resultant fluids were then incorporated into a poly(lactic acid) matrix to produce fully biodegradable composites with desirable performance. At a loading level of 10 wt%, starch fluids exhibited simultaneous enhancements in elongation at break (increase of 164.7%) and thermal conductivity (increase of 119%) of PLA composites compared to pure PLA, attributable to the good dispersion and heat-transfer properties of starch fluids. In addition, PLA composites with 10 wt% loading of starch fluids demonstrated excellent antistatic performance (3.08 × 10−4 S/cm), suggesting that polar groups of the PLA structure and PEG groups of starch fluids contributed synergistically to the electrical conductivities of composites. These results indicate that starch fluids are promising antistatic agents and plasticizers for potential applications in biodegradable materials.

Cellulose/poly(vinyl alcohol) (PVA) composite gels are prepared as separators for quasi-solid-state electrical double-layer capacitors (EDLCs) by a simple freeze-thawing method. Fourier-transform infrared spectroscopy, scanning electron microscopy and mechanical testing machine are used to characterize the structure and morphology. Compared with the PVA gel, the as-prepared composite gels show improved network structure and enhanced mechanical properties. The cyclic voltammetric curves, galvanostatic charge/discharge curves, electrochemical impedance spectroscopy and cycling performance of EDLCs with these composite gels are also evaluated. It is found that the EDLC with the optimum composite gel can work in a voltage window of 0–1.8 V and display a specific capacitance of 125.1 F g−1 (based on active carbon on one electrode) at a current density of 1 A g−1. Furthermore, it also has an excellent cycling stability with capacitance retention of ~ 88% after 1500 cycles. These results suggest that the composite gels can serve as a class of promising separators for EDLCs.

A microbial fuel cell (MFC) was used to evaluate its performance of the gaseous toluene removal in this work. The experimental results revealed that the MFC exhibited a removal efficiency as high as 88% with a toluene concentration of 300 mg m−3. Moreover, the closed-circuit MFC exhibited 1.4–3.5 times higher toluene removal efficiency compared with the open-circuit MFC, indicating that the interaction between the electrodes and microorganisms accelerates the electron transfer rate and thus enhances the microbial degradation rate. The microbial community analysis indicated that, in the toluene-powered MFC, the growth of the exoelectrogens such as Arcobacter and Geobacter were inhibited and the toluene degraders such as Chryseobacterium and Zoogloea prevailed in the MFC. For example, Arcobacter was almost disappeared and Geobacter was decreased by 40% as the fuel in the MFC switched from the acetate to toluene. Moreover, compared with Chryseobacterium, Zoogloea exhibited a high activity in the toluene removal as evidenced by the relationship between microbial community and its performance. Furthermore, the cyclic voltammetry analysis showed that an oxidation peak at −0.31 V vs Ag/AgCl and an apparent redox-area at −0.1 to +0.2 V vs Ag/AgCl was observed compared to the abiotic control, which are typical to the menaquinone and the outer membrane cytochromes (OMC) such as OmcZ, OmcS, a-type, and d-type. Therefore, a direct electron transfer pathway involving the menaquinone and OMC were proposed in the toluene-powered MFC. This work will provide some insight into development of gaseous VOCs-powered MFC and a novel technology for the VOCs removal.

A room temperature ionic liquid is immobilized on the surfaces of layered double hydroxides to form a solvent-free fluid via a silylation reaction. A series of solid polymer electrolyte membranes based on quaternized polysulfone and the solvent-free fluid are fabricated by solution casting method, which are tough and flexible and display moderate KOH aqueous solution uptakes. A symmetric electrical double-layer capacitor is assembled by using an optimized quaternized polysulfone-based solid polymer electrolyte membrane with KOH solution and two activated carbon electrodes. The single carbon electrode delivers a specific capacitance of 114.0 F g−1 at a current density of 1 A g−1 and outstanding cycling stability, indicating that this novel solid polymer electrolyte membrane may be appropriate for electrical double-layer capacitors.

UV-blocking, superhydrophobic and robust cotton fabrics were successfully developed by combination of polyvinylsilsesquioxane (PVS) and nano-TiO2 for the first time. The influence of the add-on amount on morphologies, ultraviolet (UV) protection, hydrophobicity, mechanical properties, rigidity and thermal degradation of the treated cotton fabrics was studied. The nano-TiO2 particles were found to be embedded in the PVS film layer on the surface of cotton fibers by covalent Ti–O–Si bonds after curing. The UV blocking and hydrophobic properties of the functionalized cotton fabrics were also improved with increases in the amount of add-on, compared to the reference materials. The improvements on the UV blocking, water repellency and rigidity of the treated cotton fabrics are likely attributed to synergism between the PVS polymer and nano-TiO2. The mechanical properties of the finished cotton fabrics are significantly enhanced by treatment of composite coatings. However, the resistance to thermal degradation evidently did not change despite changes in the add-on amount. Hence this strategy for developing the composite coatings can guide in constructing the advanced functional surface, and the discovery of this new class of UV-blocking, superhydrophobic and robust cotton fabrics has many potential applications such as advanced UV-blocking textiles, stretchable electronic devices and self-cleaning fields.

A new isolate identified as Rhodococcus sp. ZJUT312 via taxonomic and 16S rRNA analysis was used for the efficient degradation of benzene, toluene, ethylbenzene, and xylene (BTEX). The strain ZJUT312 was able to degrade all the BTEX. Their average biodegradation rates followed the order o-xylene > ethylbenzene > toluene > benzene > m-xylene > p-xylene. The degradation rate of o-xylene reached as high as 0.117 mmol L−1 h−1, which was one to two orders of magnitude higher than that of all other reported o-xylene degrading bacteria. GC-MS analysis revealed that o-xylene degradation pathway mainly proceeded with 2-methylbenzylalcohol as an intermediate and CO2 as a final product. Mass balance analysis of the carbon element indicated that approximately 59% the o-xylene carbons were transferred to cell biomass and about 20% were mineralized into CO2. Furthermore, the o-xylene degradation kinetics fitted well with Haldane's model. The maximum specific degradation rate (0.953 h−1) was approximately 2.25 times higher than the reported data in the literature.

From the industrial viewpoint, it would be desirable to use neutral aqueous solution when applying chitosan coatings for textile treatment. However, in most cases, chitosan only dissolves in acid solvents. In this work, a self-suspended chitosan derivative with liquid-like behavior was prepared by decorating chitosan with a quaternary ammonium salt followed by ion exchange with nonylphenol polyoxyethylene ether sodium sulfate (NPES). The chitosan derivative with higher NPES content dissolved in neutral aqueous solution, and even exhibited liquid-like viscous behavior without water at room temperature. The morphology, structure, composition, and rheological behavior of the chitosan derivative were systematically characterized using various methods. It was found that incorporation of NPES into the chitosan structure could greatly enhance its dispersion, while the modulus and viscosity of the derivative gradually decreased with increasing temperature. Moreover, the novel chitosan derivative not only directly coated cotton fabric via hydrogen-bonding interaction without removing water but also improved the long-term wettability and moisture retention because of the dual-layer ion structure of the chitosan derivative. The results showed that cotton fabrics coated with such chitosan derivatives could be developed as wound dressing materials in future work.

The volatile organic compounds (VOCs) impose severe environmental issues such as haze, photochemical smog, ozone depletion, and global warming. The degradation of VOCs in the gas phase is determined by the gas-liquid mass transfer and/or the microbial activity depending on the properties of the VOCs such as solubility, bioavailability, and toxicity. Bioelectrochemical systems (BESs), integrating microbial–electro-chemical removal mechanisms, have been intensively investigated for the organic compound removal in wastewater. In BESs, the interaction between the microbes and electrodes facilitates the electron transfer rate during the organic compound degradation and hence have a great potential to enhance the microbial activity. Currently, BESs are also under development for the refractory VOCs removal both in the liquid phase and gas phase. This review summarizes the current advances of the VOCs removal by BESs in terms of the mechanisms, pathway, removal efficiency, and coulombic efficiency. Furthermore, the challenges and future perspectives on the development of the efficient BESs for VOCs removal with a high coulombic efficiency are briefly discussed. It is believed that this review provides a new insight into the biological removal of VOCs.

The coupling of wet scrubber with thermally activated persulfate (PS) for the removal of gaseous p-xylene was studied in the present work. The effects of process parameters (i.e., activation temperature, gas flow rate, PS dosage, and absorption solution pH) on p-xylene removal were studied. The removal efficiency increased with the activation temperature and PS dosage, while decreased with the increase of gas flow rate. The inhibition effect was observed when the pH of the reaction system was alkaline due to the existence of NH3(aq) resulting from ammonium translation. P-xylene was efficiently eliminated under the optimal conditions with a maximum removal efficiency of 78.5%. The most important radicals, namely, SO4 − and HO , were investigated by electron paramagnetic resonance, and the selectivity of SO4 − was determined by quenching tests. HO and SO4 − oxidations accounted for 41.3% and 37.4% of the removal of p-xylene, respectively. The contribution of SO4 − increased with the accumulation of H+. Moreover, the absorption solution reused via adding PS and it still showed perfect removal capacity for p-xylene at the end of each cycle. Finally, a possible degradation pathway of p-xylene was proposed based on the measurements of intermediates being detected in the gas and liquid phases.

Functionalized magnesium hydroxide fluids (MHFs) with both grafting reactive acrylate groups and organic long chain ion are successfully fabricated and then incorporated in poly(ethylene glycol) diacrylate (PEGDA) to produce flexible MHFs/PPEGDA coated hybrid cotton fabric via UV photo-polymerization. The morphology, composition, transparency, rheological behavior, mechanical and flame retardant properties of MHFs/PPEGDA coating are systematically characterized by various techniques. It is found that tensile strength and young’s modulus of MHFs/PPEGDA/cotton composite are as high as 46 and 556 MPa at MHFs loading amount of 40 wt%, respectively, an enhancement of 58.6 and 66.4% in comparison with PPEGDA/cotton composite. What’s more, the addition of MHFs not only reduces the surface energy of PEGDA to improve its film-forming property during polymerization process, but also maintains high transparency over 90%. Besides the above mentioned advantages, MHFs/PPEGDA coating as thermal induced shape memory material could be fixed their shape at − 4 °C and rapidly recover their original shape at 60 °C, which is related to the melting transition temperature of MHFs. More importantly, with the synergistic effect of magnesium hydroxide and surface grafted organic long chain ion molecules, the flame retardant property of MHFs/PPEGDA/cotton is also significantly improved. These functionalized organic/inorganic fluids provide a simple approach to fabricate high performance cellulose fabrics with tunable properties in the textile industry.

A convenient and green approach was utilized to prepare the suspended carbon black fluids (SCBF) using carboxylic CB nanoparticles with diameters of 15nm as the core and poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO-b-PPO-b-PEO) as surface modifier via hydrogen bonding interaction. It was found that when the total polymer content (strongly adsorbed layer and weakly adsorbed or free layer) was greater than 60wt%, the SCBF exhibited liquid-like behavior without solvent. More interestingly, the flow mechanism mainly related to surface polymer content, which greatly differed from ionically or covalently nanofluids systems. Besides, the thermal, dispersibility, electrical conductivity properties and rheological behaviors, as well as microstructure of SCBF were systematically investigated using various methods. Moreover, the SCBF as fillers were used to prepare SCBF/Poly(vinyl alcohol) (PVA) composites for producing the simultaneous reinforcement and plasticization effect due to the unique fluidity of SCBF and interfacial interactions between the PVA molecules and SCBF via hydrogen bondings. Keywords: Nanofluids, Reinforcement, hydrogen bonds, Nanocomposites

Nanofibers based on natural polymers have recently been attracting research interest as promising materials for use as skin substitutes. Here, we prepared photocrosslinked nanofibrous scaffolds based on methacrylated chitosan (MACS) by photocrosslinking electrospun methacrylated chitosan/poly (vinyl alcohol) (PVA) mats and subsequently removing PVA from the nanofibers. We comprehensively investigated the solution properties of MACS/PVA precursors, the intermolecular action between MACS and PVA components, and the morphology of MACS/PVA nanofibers. Results indicated that the fiber diameter and morphology of the photocrosslinked methacrylated chitosan-based nanofibrous scaffolds were controlled by the MACS/PVA mass ratio and showed highly micro-porous structures with many fibrils. In vitro cytotoxicity evaluation and cell culture experiments confirmed that MACS-based mats with micro-pore structure were biocompatible with L929 cells and facilitated cellular migration into the 3D matrix, demonstrating their potential application as skin replacements for wound repair.

Two anions (dodecylbenzenesulfonate anion and stearate anion) are employed to synthesize intercalated layered double hydroxides (LDH) by co-precipitation method. Then the intercalated LDHs are incorporated in the casting solutions of chloromethylated polysulfone (CMPSF) for fabricating quaternized polysulfone/LDH nanocomposite membranes. Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, and mastersizer laser particle size analysis are used to characterize the structure and morphology of LDHs and membranes. The properties of the composite membranes including water uptake, mechanical property, thermal stability, and ionic conductivity are investigated. Compared with other anion exchange membranes, both nanocomposite membranes containing 5% LDH sheets displayed better balanced performance. They exhibit the ionic conductivity of 3.58 × 10−2 S cm−1 and 3.86 × 10−2 S cm−1 at 60°C, respectively. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers

A novel strategy for fabricating nanocomposite anion exchange membranes (AEM), which can construct self-assembled ionic channels via in situ Menshutkin reaction, is proposed. The TEM image of a nanocomposite AEM based on chloromethylated polysulfone (CMPSF) and functionalized polyhedral oligomeric silsesquioxane (POSS) confirms the existence of core-shell clusters. The ionic conductivity of these nanocomposite AEMs shows a notable increase when the content of functionalized POSS exceeds the percolation threshold. Furthermore, the optimized nanocomposite AEM has higher ionic conductivity than the control AEM with similar ion-exchange capacity due to the well-developed morphology.

Highly hydrophobic cotton fabrics were fabricated via coordination assembly of tannic acid (TA) and Fe(III) followed by treatment with 1-octadecylamine. Scanning electron microscopy analysis showed that this novel Fe(III)/TA metalorganic system coated the cotton fabrics and affected the surface roughness, making the textiles hydrophobic. This approach is facile and low cost without substrate limitation or addition of fluorinated chemicals. Wettability tests showed that the highly hydrophobic textiles were robustly resistant to acid, alkaline, and salt corrosion and long-term laundering. In addition, the obtained highly hydrophobic surface could effectively separate oil–water mixtures by simple filtration. The simplicity and versatility of this direct approach inspired by polyphenol chemistry may facilitate fast development of functional textiles for many applications.

Layered double hydroxides (LDH) are prepared by controlling urea assisted homogeneous precipitation conditions. Morphology and crystallinity of LDHs are confirmed by X-ray diffraction and scanning electron microscope. After LDHs are incorporated into quaternized polysulfone membranes, transmission electron microscope is used to observe the exfoliated morphology of LDH sheets in the membranes. The properties of the nanocomposite membranes, including water uptake, swelling ratio, mechanical property and ionic conductivity are investigated. The nanocomposite membrane containing 5% LDH sheets shows more balanced performances, exhibiting an ionic conductivity of 2.36×10−2 S cm−1 at 60 °C.

A newly isolated strain was identified as Ochrobactrum sp. by 16S rRNA sequence analysis and named as ZJUTCB-1. The strain was able to degrade mono-chlorobenzene (CB) as the sole carbon and energy source under aerobic conditions. This study is the first to report the degradation of CB by the genus Ochrobactrum. The degradation rate of CB reached 170.9 μmol L−1 h−1, which is at least 6 times higher than the previously reported data. The strain can efficiently degrade CB under a rang of temperatures (30–40 °C) and pH (6.0–7.0) with optimum at 40 °C and pH 7.0. Salt concentration higher than 0.05 mol L−1 remarkably reduced the biodegradation capability. Moreover, true oxic condition was not an essential element for biodegradation given that the CB degradation rate of 210.4 μmol L−1 h−1 was obtained under microaerobic condition. Based on the Haldane kinetic model, the maximum specific growth rate was 0.895 h−1, which is the highest in ever described CB-degrading strains. According to GC-MS analysis and enzymatic assay, CB was degraded via the meta-cleavage pathway by using 2,3-dioxygenase and 2-chlorophenol as the main intermediates, producing CO2 and Cl− as the final products. The great performance of CB degradation by Ochrobactrum sp. ZJUTCB-1 provided an alternative for development of more effective and reliable biotreatment process.

Many anti-counterfeiting inks have been explored recently, most of them are commonly involved in weak fastness, high cost and long-term toxicity, impeding their real-life applications. Herein, an environment-friendly and inexpensive anti-counterfeiting ink with excellent fastness is reported. The untifake ink is developed by combining hybrid dots (silicon/carbon) with hydroxyethyl cellulose (HEC) binder. Interestingly, the HEC binder can effectively prevent from aggregation-induced quenching of hybrid dots. Subsequently, the customized patterns are successfully transferred onto different surfaces of various substrates including cotton fabric, cellulosic paper, glass, metal, silicon wafer and PET film, using the as-prepared ink by screen-printing technique, exhibiting that the hybrid dots/HEC ink possesses widespread practicability. Notably, fluorescent color of these patterns can be switchable by adjusting environmental pH-value, further imparting the as-prepared ink with excellent covert performance. This new fluorescent hybrid dots/HEC ink will be promising candidates for high-level anti-counterfeiting applications including food packaging, apparel and documents.

Functionalized liquid-like graphene@SiO 2 hybrids are fabricated by using the graphene@SiO 2 as core and nonionic copolymer as shell in aqueous solution at room temperature. The hybrid materials can flow above 45 °C and have a particular thermal invertibility. The morphology, chemical composition, dispersibility and stability, as well as rheological behavior are systematically characterized by various methods. It is shown that well-dispersed SiO 2 nanoparticles are tightly anchored on the surface of graphene sheet via hydrogen bonding interaction under the synergetic effect of 3-(trimethoxysilyl)-1-propanethiol and copolymer to prevent the aggregation of graphene sheet. What is more, the hybrid materials keep remarkably stability and dispersibility in organic solvents and aqueous solution. More importantly, rheological tests indicate that viscoelastic behavior of graphene@SiO 2 hybrids is effectively regulated through varying the amount of surface nonionic copolymer and silane coupling agent, respectively. In addition, the liquid-like graphene@SiO 2 hybrids as a novel of hybrid coating make the substrates transfer from hydrophobicity to hydrophilicity. More interestingly, the damaged coating can be self-healed under immersing water or heating conditions, respectively. This simple and environment friendly approach will benefit for fabricating large scale graphene based hybrid materials in application of functional coating and rheological additives.

In this paper, three organic intercalating agents containing cations [hexadecyl trimethyl ammonium bromide (CTAB), poly(acrylamide-co-diallyldimethylammonium chloride), and quaternized polyethyleneimine] are used to prepare intercalated montmorillonites (MMT) by ion-exchange method. Then the modified MMTs are doped with vinylbenzyl chloride and styrene copolymer [poly(vinylbenzyl chloride-co-styrene)] for fabricating composite anion-exchange membranes (AEM). Fourier transform infrared, X-raydiffraction, thermogravimetric analysis, scanning electron microscopy, and Mastersizer laser particle size analyzer are employed to characterize the structure and morphology of MMTs and AEMs. The successful intercalation of MMTs is approved, and the MMT intercalated by CTAB shows an interlayer distance of 2.31 nm. The properties of the composite membranes including water uptake, mechanical property, and ionic conductivity are investigated. Among all the AEMs, the composite membrane containing MMT sheets with CTAB demonstrates better compositive performances. It presents an ionic conductivity of 2.09 × 10−2 S cm−1 at 80°C and good alkaline solution stability. Copyright © 2016 John Wiley & Sons, Ltd.

In this paper, a novel type of clay mineral (halloysite) nanofluids was successfully synthesized through surface hydroxylated treatment and then tertiary amine and sulfonate anions. The halloysite (Hal) exhibits liquid-like behavior in the absence of solvent above 80 °C while it is a gel-like stickum at room temperature. Moreover, the morphology, rheological behavior, thermal and dispersion properties of the resultant Hal nanofluids were systematically characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray (EDX) analysis, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), UV–Vis transmission spectra and rheological test. Rheological test results show that viscoelasticity (solid-like to liquid-like transition) of Hal nanofluids were regulated by temperature variation. The unique properties of the Hal nanofluids have made this material promising in the applications as rheological additives in industrial paints and polymer processing aids fields.

Near infrared photoluminescent porous silicon nanocrystals(ncSi)-polyhedral oligomeric silsesquioxanes (POSS) polymer composites are synthesized using a combination of thermal hydrosilylation and polymerization between Vinyl-POSS and hydrogen-terminated silicon nanocrystals (ncSi:H). The synthesized materials are characterized by IR, powder X-ray diffraction and solid-state nuclear magnetic resonance (NMR) (13C and 29Si). The results demonstrate that the hydrosilylation–polymerization reaction proceeded to create chemically crosslinked Vinyl-POSS-ncSi composites in which the integrity of the POSS cages is maintained intact. Scanning electron microscope (SEM) results demonstrate that morphology of these materials depends on the weight ratio of ncSi:H to Vinyl-POSS. Brunauer–Emmett–Teller surface area analyses establish that the composites have high surface areas ranging from 290.5 to 1047.2 m2 g−1 and pore volumes from 0.64 to 1.17 cm3 g−1. The pore sizes range from 6.08 to 3.54 nm and are dependent on the weight ratio of Vinyl-POSS to ncSi:H. Photoluminescence spectroscopy shows that the absolute quantum yield of the nanocomposites is not affected by the weight ratio of ncSi:H to Vinyl-POSS. Thermal gravimetric analysis results show that the POSS polymer composites with ncSi have lower thermal stability in nitrogen atmosphere as compared with the pure Vinyl-POSS polymer. It is envisioned that future applications for these composites will likely be found in the fields of advanced materials, gas adsorption media, and biomedicine.

A series of solvent-free ionic silica (SiO2) nanofluids of 12.3–17.3 nm in diameter were synthesized by surface functionalizing nanoscale SiO2 with a charged corona and ionically tethering with oligomeric chains as canopy. The structure and properties of the nanofluids were systematically characterized by Fourier transform infrared (FTIR), differential scanning calorimeter (DSC), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and rheology tests. The resultant nanofluids with low-molecular-weight oligomeric as canopy are homogeneous, stable yellow-like fluids with no evidence of phase separation at room temperature, while other nanofluids containing high-molecular-weight as canopy behave like a soft glassy, and they exhibit fluidity with still high modulus and viscosity above 60°C. For deeper understanding of the nature of SiO2 nanofluids, the rheological behavior, thermal stability, as well as morphology of SiO2 nanofluids were investigated in details. The flow propertie...

Chloromethylated polysulfone is firstly converted to cationic groups under the condition of N,N,N′,N′-tetramethylethylenediamine in dimethyl sulfoxide, then blended with poly(vinyl alcohol) (PVA) solution, followed by casting, crosslinking and treatment in trimethylamine solution for constructing anion-conducting interpenetrating polymer networks (IPNs). Fourier transform infrared spectra, thermogravimetric analysis and scanning electron microscopy are employed to characterize the structure and morphology of IPNs. The properties of IPNs including water uptake, mechanical property, thermal stability and ionic conductivity are studied. Compared with the quaternized polysulfone membrane, the IPN derived from 60% CMPSF and 40% PVA shows better balanced properties. It exhibits an ionic conductivity of 1.82 × 10 −2 S cm −1 at 60 °C and nearly 80% ionic conductivity of the original value after being treated in 2 M NaOH solution for 120 h at 60 °C.

In this study, reductive sulfite (S(IV)) was innovatively introduced into activated carbon fibers supported ferric citrate (Cit-Fe@ACFs) and persulfate (PS) process for organic dye removal. The addition of S(IV) enhanced the catalytic elimination rate of organic dye Reactive Red M-3BE from 15.2% to 96.2% in 12 min ( k obs (pseudo-first-order rate constant) from 0.015 to 0.324 min −1 ). More importantly, the simultaneous removal of S(IV), which is a common inorganic pollutant, was also achieved. This Cit-Fe@ACFs/S(IV)/PS system exhibited superior sustained catalytic ability and distinguished pH-tolerant performance for the simultaneous rapid removal of dyes and inorganic S(IV). Furthermore, the reaction rate constant ( k obs ) increased with the increase of concentration of S(IV) below 1 mM, while decreased over 1 mM. Finally, various radical scavengers were used together with electron paramagnetic resonance spectroscopy to confirm that hydroxyl ( OH), sulfate (SO 4 − ) and peroxymonosulfate (SO 5 − ) radicals served as the major reactive oxygen species in the Cit-Fe@ACFs/S(IV)/PS system. This study provides a promising idea to use polluting S(IV) in sewage treatment for the simultaneous removal of organic and inorganic pollutants.

In this work, covalently crosslinked nanocomposite hydroxide conducting membranes were developed on the basis of functionalized graphene oxide and quaternized polysulfone. Fourier transform infrared attenuated total reflection spectroscopy and transmission electron microscopy were employed to characterise the structure and morphology. The properties of AEMs including water uptake, swelling ratio, mechanical properties and ionic conductivity were measured. The resultant nanocomposite membrane containing 2% functionalized graphene oxide is tough and flexible, demonstrating a water uptake of 19.44% and an ionic conductivity of 1.27 × 10−2 S cm−1 at 60 °C, a tensile strength of 14.90 MPa and a moderate elongation rate at break. Furthermore, it still maintained its flexibility and toughness after treatment in 1 M NaOH solution for 744 h at 50 °C.

Highly hydrophobic silk fabric surfaces were successfully fabricated using a simple one-step atomic layer deposition (ALD) process. The surface morphology, chemical composition, and structure of bare silk fabric and silk fabrics coated with titanium dioxide (TiO2) subjected to 800 and 1600 ALD cycles were measured using scanning electron microscopy (SEM), field-emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and scanning probe microscopy (SPM). The surface wettability of the silk fabrics was evaluated by determining their static water contact angles (WCAs) and roll-off angles. The results suggest that the good hydrophilicity of the surfaces of bare silk fabrics can be changed to high hydrophobicity by the application of TiO2 nanoparticles to their surfaces using ALD. The high hydrophobicity achieved can be attributed to the increase in roughness of the silk fabric surface. The laundering durability of TiO2-coated silk fabrics is greatly improved by increasing the thickness of the ALD TiO2 films.

Owing to the strong solid-state luminescence of aggregation-induced emission luminogen (AIEgen), polymer/AIEgen nanoparticles (NPs) have great potential in application as high-quality luminescent inks. In this work, polymer/AIEgen NPs with a particle size below 70 nm were efficiently prepared through encapsulation of AIEgens with various colors within polymeric matrix via miniemulsion polymerization. The prepared polymer/AIEgen NPs emitted bright and stable blue, green, or orange-red fluorescence. The polymer/AIEgen NP inks suitable for inkjet printing were conveniently made through addition of a non-ionic surfactant to the emulsions with corresponding polymer/AIEgen NPs. The bright, high-resolution, and UV-responsive images were printed on cotton textiles with polymer/AIEgen NP inks. The microscopic observation indicated that the polymer/AIEgen NPs could form homogenous films onto the cotton fibers. More promisingly, the prepared polymer/AIEgen NPs with various colors had good compatibility, and they could be directly mixed to prepare multicolor polymer/AIEgen NP inks for handwriting.

Ultraviolet (UV) shielding, superhydrophobic and antimicrobial cotton fabrics were fabricated using functional coatings combined with advantages of polyvinylsilsesquioxane and ZnO nanoparticles by solution immersion. The influence of composite coatings on surface morphology, water-repellence, UV shielding property, mechanical property, thermal degradation behavior and antibacterial property of the cotton fabrics was investigated respectively. It is evidently found that the cotton fabrics functionalized by composite coatings exhibited excellent UV shielding, durable superhydrophobic and antimicrobial properties as compared to the reference materials. Most notably, the mechanical properties of cotton fabrics was significantly improved by surface treatment of the composite coatings without compromising their thermal stability as compared to the pristine cotton fabric. This strategy for fabricating UV shielding and superhydrophobic cotton fabrics will guide for developing advanced functional textile in the future work, which will likely be found in many applications such as advanced protective textiles, oil/water separation, water-proof, antibacterial and self-cleaning fields.

A series of novel hydrophobic cotton fabrics with polyvinylsilsesquioxane (PVS) polymer functional coatings were successfully prepared by solution immersion. The influence of the added amount of PVS polymer on the morphology, resistance to thermal and thermooxidative degradation, and hydrophobic properties of the treated cotton fabrics was studied by attenuated total reflection infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, and water contact angle measurements, respectively. The experimental results show that the PVS polymer formed a protective film on the surface of the cotton fibers; the resistance to thermal and thermooxidative degradation, and the water-repellent properties of the novel cotton fabrics were also improved with increasing added amount of PVS polymer, compared with that of reference material. The enhancement in the thermal properties of the treated cotton fabrics can likely be attributed to synergistic carbonization between the PVS protective layer and the cellulose fibers during thermal degradation. Meanwhile, it was also found that, with increasing added amount of PVS polymer, the hydrophobicity of the treated cotton fabrics was greatly improved. The noticeable improvement in the hydrophobicity of the treated cotton fabrics is ascribed to the combination of low-surface-energy PVS film and the intrinsically rough surface of the woven cotton fabrics. This strategy for fabricating novel cellulose fabrics provides a guide for the development of high-performance functional cellulose fabrics with tunable properties in the textile industry.

Hydrogels composed of natural materials exhibit great application potential in artificial scaffolds for cartilage repair as they can resemble the extracellular matrices of cartilage tissues comprised of various glycosaminoglycan and collagen. Herein, the natural polymers with vinyl groups, i.e. maleilated chitosan (MCS) and methacrylated silk fibroin (MSF) micro/nanoparticles, were firstly synthesized. The chemical structures of MCS and MSF micro/nanoparticles were investigated using Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). Then MCS/MSF micro/nanocomposite hydrogels were prepared by the photocrosslinking of MCS and MSF micro/nanoparticles in aqueous solutions in the presence of the photoinitiator Darocur 2959 under UV light irradiation. A series of properties of the MCS/MSF micro/nanocomposite hydrogels including rheological property, equilibrium swelling, sol content, compressive modulus, and morphology were examined. The results showed that these behaviors could be tunable via the control of MSF content. When the MSF content was 0.1%, the hydrogel had the compressive modulus of 0.32±0.07MPa, which was in the range of that of articular cartilage. The in vitro cytotoxic evaluation and cell culture of the micro/nanocomposite hydrogels in combination with mouse articular chondrocytes were also investigated. The results demonstrated that the micro/nanocomposite hydrogels with TGF-β1 was biocompatible to mouse articular chondrocytes and could support cells attachment well, indicating their potential as tissue engineering scaffolds for cartilage repair.

Photocrosslinkable water-soluble maleilated chitosan and methacrylated poly (vinyl alcohol) were synthesized and therefore maleilated chitosan/methacrylated poly (vinyl alcohol) (MCS/MPVA) hydrogels were prepared under UV radiation. Series of properties of the hydrogels including rheological property, swelling behavior, morphology and mechanical test were investigated. The main results showed that the MCS/MPVA hydrogels had fast gel-forming rate (complete transformation to gel within 150s), improved compressive strength at 0.169±0.011MPa and rapid absorbent capacity. These behaviors could be tunable via the control of weight ratio of MCS to MPVA. The indirect cytotoxicity assessments demonstrated the photocrosslinked hydrogels was compatible to mouse fibroblasts (L929 cells), indicating their potential as tissue engineering scaffolds.

It is a challenge to synthesize transparent polydimethylsiloxane (PDMS) materials that can completely absorb the light energy of ultraviolet (UV) A, B, and C regions. Herein, near-infrared (NIR) photoluminescent PDMS composites with hydrogen-terminated silicon nanocrystals (ncSi:H) or decyl-terminated silicon nanocrystals (ncSi-decyl) fabricated by combination of hydrosilylation and polymer encapsulation are reported. Their morphologies, optical and mechanical properties, and thermal stabilities are investigated. It is interesting to find that these PDMS composites filled with even a very small amount of ncSi:H or ncSi-decyl have unprecedented UV-blocking properties and superior thermal stabilities as compared to the PDMS reference. In particular, the ncSi-decyl/PDMS composite possesses impressive photoluminescence. Furthermore, ncSi-decyl are favorable for reinforcing the mechanical properties of the PDMS composites as compared to the PDMS reference and the ncSi:H/PDMS composite. The enhancement in the mechanical properties and thermal stabilities of these novel PL PDMS composites depends upon the creation of crosslinkable sites and entanglement interactions between the PDMS chains and the ncSi. These results suggest that potential applications for NIR photoluminescent ncSi/PDMS composites will likely be found in the fields of advanced UV-blocking textiles, cosmetics, photofluids, stretchable electronic devices, anticounterfeiting materials, biological imaging, and diagnostics.

A strategy of immobilizing room temperature ionic liquid (RTIL) in proton-exchange membranes (PEMs) is demonstrated for the first time. After synthesized by ionic exchange and extraction, RTIL is anchored to the surfaces of silica nanoparticles (SiO2-RTIL) via condensation reaction. Then composite PEMs consisting of sulfonated poly(ether ether ketone) (SPEEK) and silica with RTIL are prepared through the solution casting method. The incorporation of SiO2-RTIL markedly improves the physical properties of the composite PEMs as compared to the plain SPEEK membrane, which was probably related to the plasticization and additional proton conductivity of the SiO2-RTIL. The anhydrous proton conductivity of the resultant composite PEM with 30% SiO2-RTIL was 50 times that of the plain membrane at 150[Formula: see text]C.