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A conical-shaped atmospheric pressure plasma jet (CS-APPJ) was developed to overcome a standard limitation of APPJs, which is their small treatment area. The CS-APPJs increase the treatment area but use the same gas flow. In the present work, polypropylene samples were treated by CS-APPJ and characterized by scanning electron microscope (SEM), the contact angle, Fourier-transformed infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). It was observed that the treatment co-occurs on the face directly in contact with the plasma and on the opposite face (OF) of the samples, i.e., no contact. However, the treatment changed the chemical composition on each side; the OF is rougher than the direct contact face (DCF), probably due to the oxygen groups in excess at the DCF and nitrogen in quantity at the OF. Although simultaneous treatment of both sides of the sample occurs for most atmospheric plasma treatments, this phenomenon is not explored in the literature. [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) is one of the attractive conducting polymers that have been investigated as energy storage materials in devices like supercapacitors. Previously, we have reported a free-standing soft PPy membrane synthesized through interfacial polymerization in which methyl orange (MO) and ferric chloride were used as nano template and oxidant. In this work, we report that the presence of MO and the treatment of the PPy–MO membrane with sulfuric acid can dramatically increase the specific capacitance of the membrane. The properties of the membranes were evaluated using scanning electron microscope (SEM) for morphology, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) for chemistry, thermogravimetric analysis (TGA) for thermal stability, and cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) for electrochemical activity. It was found that the areal specific capacitance of the PPy membrane increased from 2226 mF/cm2 to 6417 mF/cm2 and the charge transfer resistivity decreased from about 17 Ω to 3 Ω between 10,000 and 0.1 Hz due to the presence of MO and the acid treatment. It is likely that the superposition effect of MO and acid treatment helped the charge transfer process and consequently enhanced the charge storage performance and specific capacitance of the PPy membrane. [ABSTRACT FROM AUTHOR]

Hydrophobic surfaces have aroused considerable attention because of their extensive potential applications. In this work, we developed a facile strategy for fabricating hydrophobic and anti-fouling surfaces on wood substrates. The modification was accomplished simply by immerging wood into the tetramethylcyclotetrasiloxane (D4H) modifier solution for 5 min. The D4H modified wood was characterized using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscope, and energy dispersive spectrometer. The result shows that the D4H modified wood had good hydrophobicity, and the water contact angle of wood in the radial and cross sections reached 140.1° and 152°. In addition, the obtained hydrophobic wood surface also showed anti-fouling properties, UV resistance and could withstand the tape peel test and finger wiping. [ABSTRACT FROM AUTHOR]

In recent years, significant attention has been paid towards the study and application of mixed matrix nanofibrous membranes for water treatment. The focus of this study is to develop and characterize functional polysulfone (PSf)-based composite nanofiltration (NF) membranes comprising two different oxides, such as graphene oxide (GO) and zinc oxide (ZnO) for arsenic removal from water. PSf/GO- and PSf/ZnO-mixed matrix NF membranes were fabricated using the electrospinning technique, and subsequently examined for their physicochemical properties and evaluated for their performance for arsenite–As(III) and arsenate–As(V) rejection. The effect of GO and ZnO on the morphology, hierarchical structure, and hydrophilicity of fabricated membranes was studied using a scanning electron microscope (SEM), small and ultra-small angle neutron scattering (USANS and SANS), contact angle, zeta potential, and BET (Brunauer, Emmett and Teller) surface area analysis. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to study the elemental compositions and polymer-oxide interaction in the membranes. The incorporation of GO and ZnO in PSf matrix reduced the fiber diameter but increased the porosity, hydrophilicity, and surface negative charge of the membranes. Among five membrane systems, PSf with 1% ZnO has the highest water permeability of 13, 13 and 11 L h−1 m−2 bar−1 for pure water, As(III), and As(V)-contaminated water, respectively. The composite NF membranes of PSf and ZnO exhibited enhanced (more than twice) arsenite removal (at 5 bar pressure) of 71% as compared to pristine PSf membranes, at 43%, whereas both membranes showed only a 27% removal for arsenate. [ABSTRACT FROM AUTHOR]

The bio-oil phenol-formaldehyde (BPF) resin, prepared by using bio-oil as a substitute for phenol, has similar bonding strength but lower price to phenol-formaldehyde (PF) resin. As a common adhesive for outdoor wood, the aging performance of BPF resin is particularly important. The variations in mass, bonding strength, microstructure, atomic composition, and chemical structure of BPF resin under five aging conditions (heat treatment, water immersion, UV exposure, hydrothermal treatment, and weatherometer treatment) were characterized by scanning electron microscope, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy, respectively. Compared under five aging conditions, after aging 960 h, the mass loss of plywood and film was largest under hydrothermal treatment; the bonding strength of plywood, the surface roughness, and O/C ratio of the resin film changed most obviously under weatherometer treatment. FT-IR analysis showed that the decreased degree of peak intensity on CH2 and C–O–C characteristic peaks of BPF resin were weaker under water immersion, hydrothermal treatment, and weatherometer treatment than those of PF resin. The comparison of data between BPF and PF resins after aging 960 h showed that adding bio-oil could obviously weaken the aging effect of water but slightly enhance that of heat. The results could provide a basis for the aging resistance modification of BPF resin. [ABSTRACT FROM AUTHOR]

A new adsorbent(A-PGMA) has been synthesized via functionalizing poly(glycidyl methacrylate) microsphere with 2-aminothiazole and used to adsorb gold ions from aqueous solutions. The adsorbent was characterized by X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET), Zeta potential, scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR). The influence factors such as the pH value of the solution, the initial gold ion concentration and the contact time were examined. Simultaneously, the adsorption process of the gold ion on A-PGMA fitted well with the Langmuir and pseudo-second-order models, respectively. The results showed that the maximum adsorption capacity was 440.54 mg/g and the equilibrium time of adsorption was about 3 h under pH 4. Moreover, the adsorbent has a high reusability after five cycles and good selectivity from coexisting ions, including Zn(II), Mg(II), Cu(II), Ge(IV) and B(III). The adsorption mechanisms of gold ions were ion exchange and chelation between the sulfur and nitrogen groups on the surface of A-PGMA and AuCl4-. Therefore, the adsorbent has a great potential for adsorption of gold ions from aqueous solutions. [ABSTRACT FROM AUTHOR]

100% grey cotton knitted fabric contains impurities and yellowness and needs to be prepared for processing to make it suitable for coloration and finishing. Therefore, conventionally 100% grey cotton knitted fabric undergoes a process of scouring and bleaching, which involves the use of large amounts of water and chemicals, in order to remove impurities and yellowness. Due to increased environmental awareness, pursuing a reduction of water and chemicals is a current trend in textile processing. In this study, we explore the possibility of using atmospheric pressure plasma as a dry process to treat 100% grey cotton knitted fabric (single jersey and interlock) before processing. Experimental results reveal that atmospheric pressure plasma treatment can effectively remove impurities from 100% grey cotton knitted fabrics and significantly improve its water absorption property. On the other hand, if 100% grey cotton knitted fabrics are pretreated with plasma and then undergo a normal scouring process, the treatment time is reduced. In addition, the surface morphological and chemical changes in plasma-treated fabrics were studied and compared with the conventionally treated fabrics using scanning electron microscope (SEM), Fourier-transform infrared spectroscopy-attenuated total reflection (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS). The decrease in carbon content, as shown in XPS, reveal the removal of surface impurities. The oxygen-to-carbon (O/C) ratios of the plasma treated knitted fabrics reveal enhanced hydrophilicity. [ABSTRACT FROM AUTHOR]

The publication presents the results of investigations of the influence of dye dopant on the electrooptical and morphology properties of a polymeric donor:acceptor mixture. Ternary thin films (polymer:dye:fullerene) were investigated for potential application as an active layer in organic solar cells. The aim of the research is to determine the effect of selected dye materials (dye D131, dye D149, dye D205, dye D358) on the three-component layer and their potential usefulness as an additional donor in ternary cells, based on P3HT donor and PC71BM acceptor. UV–vis spectroscopy studies were performed, and absorption and luminescence spectra were determined. Ellipsometry parameters for single dye and ternary layers have been measured. The analyses were performed using the Raman spectroscopy method, and the Raman spectra of the mixtures and single components have been determined. Organic layers were prepared and studied using scanning electron microscope and atomic force microscope. For dyes, ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy studies were carried out and the ternary system was presented and analyzed in terms of energy bands. [ABSTRACT FROM AUTHOR]

In present study, novel nitrogen doped carbon dots (NCDs) are synthesized using a green material—dopamine—as a precursor and studied as corrosion inhibitors for Q235 carbon steel in 1 M HCl solution. According to the electrochemical results, it is found that NCDs acting as a mixed-type corrosion inhibitor can effectively retard the acid corrosion of carbon steel, and their inhibition efficiency increases with the concentration increasing from 50 to 400 ppm. The highest inhibition efficiency is 96.1% in the presence of 400 ppm NCDs at room temperature. Additionally, the adsorption of NCDs obeys the Langmuir adsorption isotherm. In addition, weight loss results show that the inhibition efficiency in the presence of 400 ppm NCDs increases with prolonged exposure time and rising temperature (298–328 K), owing to the strong adsorption of NCDs on the steel surface, and the η value is 92.2% at 60 h of immersion and 86.2%, 89.1%, 90.6% and 92.9% at 298, 308, 318 and 328 K, respectively. Surface analysis by scanning electron microscope (SEM), laser scanning confocal microscope (LSCM) and X-ray photoelectron spectroscopy (XPS) further proves the formation of a protective NCD film on the steel surface. [ABSTRACT FROM AUTHOR]

This study consists of two parts. In the first, the woven polyester fabric, after washing to remove lubricant oils, was treated with the dielectric barrier discharge (DBD) plasma at the short plasma exposure time (from 15 to 90 s). The effect of the plasma exposure time on the activation of the polyester fabric was assessed by the wicking height of the samples. The results show that the wicking height in the warp direction of the plasma-treated samples improved but was virtually unchanged in the weft direction. Meanwhile, although the tensile strength in the warp direction of the fabric was virtually unaffected despite the plasma treatment time up to 90 s, in the weft direction it increased slightly with the plasma treatment time. Scanning Electron Microscope (SEM) images and the X-ray Photoelectron Spectroscopy (XPS) spectra of the samples before and after the plasma treatment were used to explain the nature of these phenomena. Based on the results of the first part, in the second part, two levels of the plasma treatment time (30 and 60 s) were selected to study their effect on the polyester fabric dyeability with disperse dyes. The color strength (K/S) values of the dyed samples were used to evaluate the dyeability of the fabric. The SEM images of the dyed samples also showed the difference in the dyeability between the plasma-treated and untreated samples. A new feature of this study is the DBD plasma treatment condition for polyester fabrics. The first is the use of DBD plasma in air (no addition of gas). Second is the very short plasma treatment time (only 15 to 90 s); this condition will be very favorable for the deployment on an industrial scale. [ABSTRACT FROM AUTHOR]

The development of antibacterial materials has great importance in avoiding bacterial contamination and the risk of infection for implantable biomaterials. An antibacterial thin film coating on the surface via chemical bonding is a promising technique to keep native bulk material properties unchanged. However, most of the polymeric materials are chemically inert and highly hydrophobic, which makes chemical agent coating challenging Herein, immobilization of chlorhexidine, a broad-spectrum bactericidal cationic compound, onto the polylactic acid surface was performed in a multistep physicochemical method. Direct current plasma was used for surface functionalization, followed by carbodiimide chemistry to link the coupling reagents of N-(3-Dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDAC) and N-Hydroxysuccinimide (NHs) to create a free bonding site to anchor the chlorhexidine. Surface characterizations were performed by water contact angle test, X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The antibacterial activity was tested using Staphylococcus aureus and Escherichia coli. Finally, in vitro cytocompatibility of the samples was studied using primary mouse embryonic fibroblast cells. It was found that all samples were cytocompatible and the best antibacterial performance observed was the Chlorhexidine immobilized sample after NHs activation. [ABSTRACT FROM AUTHOR]

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants. [ABSTRACT FROM AUTHOR]

In this study, waste cotton fibers were environmentally reused. First, they were milled into fine powders with particle sizes of around 30 µm and dyed for use as pigments. Dyeing properties of the cellulose powder were explored by determining the dye uptake, K/S value, and bath ratio. Among the various samples, powders with owf (on weight of fabric) of 0% dye (pristine cellulose powder), and 10% and 50% dyed powders were selected; and these powders were characterized by several methods to compare the properties of dyed and undyed cellulose. The surface morphologies of the powders were observed with a scanning electron microscope (SEM). Combining the SEM images with the Brunauer–Emmet–Teller (BET) data, it was found that the smaller the particle size, the larger is the surface area. In addition, the X-ray photoelectron spectroscopy (XPS) results revealed that with increasing dye concentration, the intensity of the C peak reduced, while those of O and S increased. Moreover, the main components of the dyed and undyed cellulose powders were found to be almost the same from the Fourier-transform infrared spectroscopy (FTIR) results. Finally, the dynamic mechanical analysis (DMA) data revealed that the loss modulus was significantly larger than the storage modulus, demonstrating that the material mainly undergoes viscous deformation. [ABSTRACT FROM AUTHOR]

In this paper, rigid polyurethane foams that were filled with expandable graphite (RPUF/EG) composites were prepared by the liquid blending method, and then the structure and flame retardancy performance of materials were investigated through optical microscope, scanning electron microscope, limit oxygen index, cone calorimeter, thermogravimetric analysis coupled to fourier transform infrared spectrum, and X-ray photoelectron spectroscopy. The results showed that a large number of EG could be good to the exhibition of flame retardancy of RPUF, where the optimal material was found at loading 15 phr EG that showed an increased limit oxygen index value and a decreased calorific or fuming value. TGA coupled FTIR and XPS revealed that EG could disassembled before RPUF under heating treatment, and it could form a pyknotic and enahnced residual carbon layer on RPUF surface after the fire, which restricted the transfer of gas, like oxygen or heat into PU matrix, finally resulting in the promotion of flame retardancy of RPUF. [ABSTRACT FROM AUTHOR]

The nanomaterial of graphene oxide grafting poly (N-isopropylacrylamide) (GO-g-PNIPAAm) was synthesized and PVDF/GO-g-PNIPAAm blended membranes were fabricated by wet phase inversion. In this work, a hydrophilic nanomaterial GO-g-PNIPAAm with poly(N-isopropylacrylamide) (PNIPAAm) grafted on GO, was synthesized by the atom transfer radical polymerization (ATRP) method. The resulting nanomaterial was confirmed by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectrum, and X-ray photoelectron spectroscopy (XPS) analysis. The synthesized GO-g-PNIPAAm was incorporated with polyvinylidene fluoride (PVDF) via phase inversion, and investigated for its temperature sensitivity, porosity, contact angle, scanning electron microscopy, and permeate properties. The water contact angle measurements confirmed that GO-g-PNIPAAm nanomaterial-endowed PVDF membranes with better hydrophilicity and thermo-responsive properties compared with those of the pristine PVDF membranes. Bovine serum albumin (BSA) adsorption experiments suggested that excellent antifouling properties of membranes were acquired after adding GO-g-PNIPAAm. The modified membranes showed good performance when the doping amount of GO-g-PNIPAAm was 0.2 wt %. [ABSTRACT FROM AUTHOR]