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In this work, robust superhydrophobic cotton fabrics with UV shielding, self-cleaning, photocatalysis, and oil/water separation were successfully prepared based on micro/nano hierarchical ZnO/HNTs (halloysite nanotubes) hybrid particles and silicone elastomer polydimethylsiloxane (PDMS). ZnO/HNTs hybrid particles were prepared by in-situ growth of ZnO nanoparticles on the surface of halloysite nanotubes (HNTs). ZnO/HNTs hybrid particles and PDMS were used to successively coat cotton fabric by dip-coating approach. The coated cotton fabric displayed excellent superhydrophobicity with a water contact angle of 162.5 ± 1° and photocatalytic degradation of methylene blue solution under UV irradiation owing to the roughness and photocatalytic performance provided by micro/nano hierarchical ZnO/HNTs hybrid particles and low surface energy achieved by PDMS. The as-prepared fabric also displayed outstanding self-cleaning and antifouling properties. In addition, due to its both superhydrophobic and superoleophilic characteristics, the as-prepared cotton fabric can be used to separate several oil/water mixtures and showed good recoverability. The superhydrophobic cotton fabric also exhibited excellent UV shielding performance with a large UV protection factor of 1643.28 due to strong ultraviolet-absorption, light scattering and frequent light reflection of ZnO nanoparticles in ZnO/HNTs composites coated on cotton fabric. Importantly, the as-prepared fabric retained superhydrophobic performance after 2000 cycles rubbing, 90h UV illumination, and immersing in acidic and alkali solutions with different pH values ranging from 1 to 14 for 1 h. These characteristics make multifunctional cotton fabrics a satisfactory candidate in various promising fields.

In this work, a green, simple, low-cost, and highly effective sol–gel method was used to successfully fabricate water-based SiO2–TiO2 aerogels with the help of surfactant by the incorporation of TiO2 into methyltrimethoxysilane-based SiO2 sol. The surface morphologies, chemical composition, physical properties, wettability and photocatalytic activity of SiO2–TiO2 aerogels were characterized by Fourier transformed infrared (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), water contact angle and ultraviolet–visible absorption spectrum measurements. When the molar ratio of Si to Ti was 10:1, the SiO2–TiO2 aerogel samples showed not only low bulk density (0.122 g cm−3) and high porosity (96.11%), but also the high-efficient photodegradation ratio of 98.30% under UV light for 150 min. The obtained SiO2–TiO2 aerogels were photocatalytically active and superhydrophobic with the water contact angle (WCA) of 152°, showing the promising potential wide application. Moreover, the superhydrophobic and photocatalytic properties of the SiO2–TiO2 aerogels coated cotton fabric were also investigated. The coated cotton fabric not merely possessed antifouling, liquid-repellent and self-cleaning capabilities due to its superhydrophobic property, but also performed the considerable photocatalytic activity by the decomposition of methylene blue (MB) and Rhodamine B (RhB) under ultraviolet (UV) exposure.

In this paper, a simple and effective method to prepare Ag–Ce/ZnO nanorods photocatalyst and grow them controllably on modified polyester fabrics was presented to fabricate multifunctional textiles. Analytical grade zinc acetate dihydrate and sodium hydroxide were used as the main raw materials to prepare Ag–Ce/ZnO nanorods. Morphological, structural and chemical characterization of the Ag–Ce/ZnO nanorods was performed by XRD, UV-vis and other spectroscopies. The results showed that the Ag–Ce/ZnO nanorods had a hexagonal wurtzite structure. After 60 minutes of irradiation under ultraviolet light, the Ag–Ce/ZnO nanorods showed a percentage photodegradation of 93.14% for a methylene blue (MB) solution. Modified polyester fabrics covered with the Ag–Ce/ZnO nanorods were then prepared in a water bath. By a series of tests, it was observed that the Ag–Ce/ZnO nanorods on the modified polyester surface were neatly arranged and had good photocatalytic properties. Moreover, the UPF of the modified polyester fabric after finishing increased from 30.4 to 877.2. The multifunctional properties of the finished fabric exhibited good durability.

A durable superamphiphobic cotton fabric was obtained by coating SiO2 aerogel particles, polydimethylsiloxane (PDMS), and 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFTES) on a cotton fabric via th...

In order to realize the characteristics of new types of wave-absorbing materials, such as strong absorption, broad bandwidth, low weight and small thickness, a hollow-structured flower-like Fe3O4@MoS2 composite was successfully prepared by simple solvothermal and hydrothermal methods in this paper. The structural properties were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Besides, the microwave properties and magnetic properties were measured using a vector network analyzer and via a hysteresis loop. SEM and TEM images revealed that MoS2 nanosheets grew on the surface of hollow nanospheres. The results showed that the composite exhibited excellent absorbing property. When the molar ratio of Fe3O4 and MoS2 was 1 : 18, the minimum reflection loss value reached −49.6 dB at 13.2 GHz with a thickness of 2.0 mm and the effective absorption bandwidth was 4.24 GHz (11.68–15.92 GHz). Meanwhile, the effective absorption in the entire X-band (8–12 GHz) and part of the C-band (4–8 GHz) and Ku-band (12–18 GHz) could be achieved by designing the sample thickness. In addition, the hollow structure effectively reduced the density of the material, which was in line with the current development trend of absorption materials. It could be predicted that the hollow core–shell structure composite has a potential application prospect in the field of microwave absorption.

The papaya leaves were extracted via ultra-pure water. The obtained papaya leaves extract (PLE) was used as the eco-friendly inhibitor for Cu in the H2SO4 corrosion medium. The experimental results showed that PLE was a mixed-type inhibitor and exhibited excellent anti-corrosion nature over a certain temperature range. Morphological analysis test results at different temperatures strongly proved the anti-corrosion nature of PLE. The XPS test results found that an adsorption film of Cu-S bond and Cu-N bond was formed on the Cu surface. This barrier film conformed to Langmuir mono-layer adsorption. Corrosion kinetics and thermodynamic parameters were calculated and discussed.

Robust superhydrophobic cotton fabrics with ultraviolet (UV)-proof performance were prepared via a simple one-pot method with composite coating of hierarchical CuS microflower nanoparticles and silicone elastomer polydimethylsiloxane (PDMS). The facile preparation of CuS microflower nanoparticles was conducted via relatively low-temperature reaction. The surface morphology, chemical composition, thermal degradation behavior, and crystal structure of the products were evaluated. The simultaneous roughening due to hierarchical rough morphology of CuS microflower nanoparticles and PDMS hydrophobization resulted in the coated fabric with microscale fibers exhibiting superhydrophobic property and its water contact angle was 159.3° ± 0.6°. The superhydrophobic textile also displayed outstanding UV-proof performance with a large ultraviolet protection factor of 535.36 due to ultraviolet-absorption, light scattering and frequent light reflection of hierarchical CuS nanoparticles. The superhydrophobic textile showed excellent stain resistance and self-cleaning property and also was able to separate oil and water with high efficiency and good separation reusability caused by the contrasting wettability of the coated textile for water droplets and oil droplets. The as-prepared superhydrophobic fabric displayed excellent robustness against 2000 cycles rubbing, water jetting and long-time UV illumination and satisfactory chemical stability. This superhydrophobic coating showed no negative impact on the mechanical strength of cotton fabric. The facile approach in favor of large-scale preparation showed promising potential for wide application of flexible superhydrophobic cotton textiles with ultraviolet-blocking performance.

In this work, solid spherical and hollow spherical CuS were prepared by microwave assisted method with PEG4000 as dispersant. The CuS was characterized by particle size analysis, scanning electron microscope(SEM), nitrogen adsorption and desorption, and X-ray diffraction (XRD), respectively. The effects of PEG4000, ratio of thiourea: copper, and microwave power on particle size of CuS were discussed, and the effects of particle size on photocatalytic property were evaluated. The solid spherical CuS had average particle size of 189.1 nm and specific surface of 9.54 m2/g. The hollow spherical CuS had average particle size of 502.7 nm and specific surface area of 16.01 m2/g. The results showed the hollow spherical CuS had better photocatalytic property. In addition, the cotton fabric was treated by hollow spherical CuS/polydimethylsiloxane (PDMS) to prepare multifunctional textile in this work. The treated cotton fabric was characterized by SEM. The treated cotton fabric achieved the superhydrophobicity with contact angle of 156.9° and sliding angle of 8°, good photocatalytic properties for methylene blue, and exceptional UV resistance with UPF of 223.52.

Fluorine-free superhydrophobic cotton fabric was fabricated by coating polyacrylate (PA)/SiO₂ nanocomposite. PA/SiO₂ nanocomposite was prepared based on the modified SiO₂ nanoparticles with double bonds and hexadecyl groups by solution polymerization of butyl acrylate (BA), methyl methacrylate (MMA) and octadecylmethacrylate (OMA). The obtained cotton fabric showed excellent superhydrophobicity with a water contact angle of 152.2±0.4° and a water shedding angle of 8.0±0.2°, due to the simultaneous introduction of surface topography constructed by modified SiO₂ nanoparticles and low surface free energy PA adhesive layer and hexadecyl groups onto cotton fibers. The as-obtained products were characterized by Fourier-transform infrared spectrometry (FT-IR), thermal gravimetric analysis (TG), scanning electron microscopy (SEM) and size distribution analysis. The obtained superhydrophobic fabric coated by PA/SiO₂ demonstrated good mechanical stability and self-cleaning. The PA/SiO₂ coating treatment caused little loss in the tensile strength, breathability, and whiteness of the treated fabric. This approach with improved human/environmental friendliness can pave the potential way for the preparation of superhydrophobic surfaces.

Superhydrophobic cotton fabrics were prepared by simultaneous incorporation of SiO₂ aerogel particles and polydimethylsiloxane (PDMS). The SiO₂ aerogels were synthesized via acid-base catalyzed sol-gel reaction with methyl trimethoxy silane (MTMS) as the single precursor and oxalic acid and ammonium hydroxide as the catalyst in methanol (MeOH) solution by drying under ambient pressure. The preparation parameters (e.g., MTMS/MeOH molar ratio, oxalic acid/MTMS molar ratio, gelation pH value, and gelation temperature) had great influences on the density and porosity of the SiO₂ aerogel. The obtained SiO₂ aerogel had low density, high porosity and high specific surface area, showing the typical rough mesoporous structure. The prepared bulk SiO₂ aerogel displayed excellent superhydrophobicity with a water contact angle (WCA) of 151.0 ± 0.8°. Superhydrophobic cotton fabric with a WCA of 155.6 ± 0.9° for a 5 μL water droplet was successfully obtained by simply coating the PDMS/SiO₂ aerogel composite solution via dip-pad-cure process. This could be attributed to the combination of SiO₂ aerogel particles with porous rough microstructure, high specific surface area and PDMS adhesive layer with low surface energy. The effect of PDMS/SiO₂ aerogel coating treatment on the mechanical strength properties of the cotton fabrics was negligible. This simple approach may pave the potential way for practical applications.

Cu–Bi co-doped ZnO nanospheres were obtained by adopting Bi and Cu to dope ZnO to improve their photocatalytic performance in the visible region. Cu–Bi co-doped ZnO nanospheres were successfully grown on the surface of cotton fabric by a sol–gel assisted hydrothermal method with citric acid as a morphology control agent. The obtained products were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance spectroscopy (DRS). The results showed that the size of ZnO nanospheres was about 200 nm and doping with Cu and Bi did not change their morphology. Cu–Bi co-doped ZnO nanospheres presented a hexagonal wurtzite structure with high crystallinity; meanwhile, their band gap was also obviously reduced due to doping, from 3.24 eV to 2.82 eV. Cu–Bi co-doped ZnO nanospheres endowed the cotton fabric with excellent UV (ultraviolet) resistance with a UPF (Ultraviolet Protection Factor) value of 283.54 after 40 washes. Cotton fabric with 3% Bi–5% Cu co-doped ZnO on the surface showed 98.66% degradation of methylene blue (MB) solution under visible light irradiation for 150 min, indicating remarkable photocatalytic performance.

Superabsorbent polymers as soft materials that can absorb water have aroused great interest in the fields of agriculture and forestry. Water absorption and water retention performance of a hydrogel are important indicators to evaluate its practical application. However, few reports show that hydrogels have both excellent water absorption and water retention properties. To date, superabsorbent hydrogels with a swelling capacity of more than 3000 g g−1 have rarely been reported. In this work, a novel superabsorbent poly(acrylic acid) (PAA)-based nanocomposite hydrogel (NC gel) was prepared via free radical polymerization of acrylic acid by using vinyl hybrid silica nanospheres (VSNPs) as the cross-linking agent. The PAA NC hydrogel achieved a great swelling ratio of more than 5000 times in deionized water at 323 K, and the swollen hydrogel could hold 60% moisture when it was exposed to the air at 303 K for 42 h. Moreover, the hydrogel also obtained a good swelling ratio of 136 g g−1 in NaCl solution. The PAA NC hydrogel showed excellent repetitive swelling ability. The influences of variable factors (acrylic acid, initiator and sodium hydroxide) on the swelling ratio of the NC hydrogel were researched. It can be speculated that the PAA NC hydrogel has potential application in agriculture and forestry areas due to its excellent water absorption and water retention properties.

A novel Z-scheme flower-like Ag2WO4/Bi2WO6 (AWO/BWO) photocatalyst with excellent photocatalytic activity for the contaminant degradation was successfully fabricated through a facile hydrothermal-precipitation method. Various characterization techniques and electrochemical measurements were exploited to study the morphology, structure, photoelectrical property of the photocatalyst. The photocatalytic efficiency for rhodamine B (RhB) degradation over the 3 wt% AWO/BWO composite was nearly 100% within 150 min under visible light, which was 11.5 and 1.5 times higher than pure AWO and BWO. The enhanced photocatalytic performance was attributed to the direct Z-scheme heterojunction, which not only achieved high separation efficiency of photogenerated electrons and holes but also retained strong redox capability of the composite. In addition, excellent stability and recyclability of AWO/BWO composites verified the photocatalyst was suitable for practical wastewater purification. Radical trapping experiment revealed that the dominant reactive species participating in the RhB degradation were superoxide radical( O2–) and holes (h+). Furthermore, a possible mechanism for RhB degradation and charge carriers transfer path was proposed on the basis of experiment results. This work offers new insights into the construction of efficient Bi-based photocatalyst with Z-scheme heterojunction, and exhibits its potential application in the field of environmental remediation.

Superhydrophobic and ultraviolet (UV)-blocking cotton fabrics were prepared by the incorporation of TiO2/SiO2 composite nanoparticles followed by hydrophobization with hexadecyltrimethoxysilane (HDTMS). The TiO2/SiO2 composite nanoparticles were synthesized via sol-gel reaction with tetraethyl orthosilicate (TEOS) as the precursor in the presence of TiO2. As for the resulting products, characterization by Fourier-transform infrared spectrometry (FTIR), X-ray diffractometer (XRD) and scanning electron microscope (SEM) were performed respectively. The hydrophobicity measurement and ultraviolet-blocking property measurement showed that the obtained cotton fabric had a water contact angle of 159.3°, a water shedding angle of 8° and a large ultraviolet protection factor (UPF = 115.42) with UVA transmittance of 3.35%. The introduction of TiO2/SiO2 composite nanostructures onto fibers made the textiles rougher, which were highly beneficial to the formation of superhydrophobic surfaces. The high UV absorbance property of TiO2 imparted excellent UV-shielding property to the treated textiles, and effective blocking of the photoactivity of TiO2 by SiO2 resulted in the UV-durability of the superhydrophobicity on the textiles.

Durable superhydrophobic cotton textiles with ultraviolet-blocking property and photocatalytic activity were prepared by coating polydimethylsiloxane (PDMS)/copper sulfide (CuS) based on the copper sulfide with hierarchical mesoporous microstructure like flower, which was composed of self-assembled nanosheets. The treated textile showed the exceptional superhydrophobic surface whose water contact angle and shedding angle was 157.7 ± 0.9° and 7.2 ± 0.2°, respectively, due to the simultaneous introduction of hierarchical porous surface topography constructed by flower-like CuS and low surface tension PDMS layer on cotton fabric. The obtained superhydrophobic cotton fabric was also proved to possess high ultraviolet-blocking performance with a large ultraviolet protection factor (UPF) of 511.09 and good photocatalytic activity. The prepared superhydrophobic fabrics showed excellent ultraviolet-durability and laundering durability attributed to stable and firm PDMS adhesive layer. This simple approach can sho...

In this study, a continuum-based model was proposed to characterise the flexural performance and damage evolution process of a plain concrete beam under high-cycle fatigue loads. The plain concrete beam under three-point bending load was modelled by combining the damaged constitutive model of concrete and the Euler–Bernoulli beam theory with varied stiffness. The dynamic stiffness matrix method, in conjunction with the discretization technique, was adopted to solve the nonlinear governing equations of motion. A global damage index corresponding to natural frequencies was introduced to quantify the performance degradation of the beam. To improve the analysis efficiency of the high-cycle fatigue problems, the accelerated algorithm, namely the jump-in-cycle method, was employed in this model. It is demonstrated that the numerical results agree well with the experimental data under fatigue harmonic loads. Performance degradation under fatigue bending loads only occurs at the midspan of the beam. Adopting the jump-in-cycle methods significantly improves the analysis efficiency of the high-cycle fatigue problem, and the calculation time is reduced by approximately 90% compared with the cycle-by-cycle method. This model is capable of rationally predicting damage evolutions, stiffness degradation processes, stress redistributions, and loading level-fatigue life (S–N) curves and can provide a basis for simulating the flexural behaviours of reinforced concrete (RC) beams under fatigue bending loads.

Flower-shaped nanometer zinc oxide and its complex incorporating La–Nd have been prepared using hydrothermal method with zinc chloride and urea as raw materials, ethylene glycol as morphology controller. The powdered samples were characterized by scanning electron microscopy, X-ray diffractometry, photocatalytic test with solutions of reactive dyes as indicators. In conclusion, the optimum doping ratios of La/Nd are considered to be 3%/3%. When 3%La–3%Nd/ZnO was served as photocatalyst, considerable degradations of dyes were caused under the ultraviolet and visible light without exception, owing to the expanded excitation wavelength and reduced band gap of ZnO after incorporating. While using the compound material in effluent treatment containing reactive dyes, the decomposition rate of dyes, respectively, reached 99.99% and 80% or more under UV-light and visible irradiation for 60 min, appreciable removal effects of organic pollutants were obtained, testifying 3%La–3%Nd/ZnO to be a splendid UV-Vis catalyst.

A facile method to prepare acid-resistant fabric with fluoropolymer/silicon dioxide (SiO2) nanocomposite is presented in this study. Response surface methodology (RSM) was employed to understand the influence factors of the optimized protocol for the acid-resistant fabric. During the preparation process, the effect level of the factors was agent concentration > curing temperature > curing time. The treated fabric showed a remarkable acid repellency, having a contact angle greater than 137°. Additionally, when the fabric was immersed in 80% sulfuric acid (H2SO4) for 5 min, it had a 4% and 9% decrease in breaking force in the warp and weft directions, respectively. We believe that the acid-resistant fabric developed as part of this study will receive more opportunities to the application of protective clothing, and the regression analysis provided by RSM can be extended into other procedures for textile preparation.

A modified polyester fabric (MPF) was successfully coated with a sphere-like zinc oxide (ZnO) microstructures in water bath. The characterization of the finished fabric was carried out using SEM, XRD and EDS. UV–vis spectrophotometry was investigated for the UV-blocking property of the as-obtained sample, as well as the photocatalytic behaviour of ZnO/MPF radiated under UV-light. The findings revealed the excellent demonstration of the photocatalytic and UV-blocking properties of ZnO/MPF. The ZnO microspheres were successfully grown on the MPF, with about 87% degradation rate of Methylene blue (MB) under UV light irradiation for the duration of 60 min. The UPF of ZnO/MPF was 170.3. The strong bond existing between Zno/MPF ensured that it still retained its perfect photocatalytic and UV- blocking potential after been washed 10 times.

Adsorption treatment of dyes from industrial effluent by hydrogel adsorbent has been a research hotspot, but few high-performance hydrogel adsorbents with high adsorption capacity have been reported. Previously reported poly (acrylic acid) PAA-based hydrogel adsorbents show a low swelling ratio due to the unsatisfactory cross-linked structure, which causes a passive impact on the exhibit of adsorptive sites and the penetration of water inside the hydrogel. Herein, we prepared a novel super-adsorbent nanocomposite (NC) hydrogel adsorbent by employing vinyl hybrid silica nanoparticles (VSNPs) with average diameter of 30 nm as crosslinking agent. The introduction of an optimal content of VSNPs effectively forms a well three-dimensional network structure. The structure system of our NC hydrogel effectively promotes the active sites on the polymer chains to be exposed to dye molecules. Thus, the NC hydrogel adsorbent achieved a high adsorption capacity of 1690 mg/g for adsorbing methylene blue and obtain a high removal ratio of 90 % within 40 min. Furthermore, the hydrogel exhibits excellent reusability after 4 repeated cycles of adsorption and desorption. The work confirmed that the VSNPs can build a well covalent hybrid cross-linked system of a PAA-based hydrogel without other organic crosslinkers and further provided a new method to develop novel hydrogel adsorbent with enhanced adsorption capacity for removing organic dyes from industrial wastewater.

In this work, superhydrophobic methyltrimethoxysilane (MTMS)-based silica aerogels were fabricated via water-based sol–gel reaction by ambient pressure drying (APD) method in the presence of surfactant. The structure, morphology, and hydrophobic properties of the obtained silica aerogel were characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) methods, X-ray diffractometer (XRD), and water contact angle measurement. The effects of the concentration of MTMS, the pH value of the solution, and the amount of surfactant cetyltrimethylammonium bromide (CTAB) on properties of silica aerogels were investigated, respectively. Increasing the concentration of MTMS to a great extent resulted in higher density and lower porosity of silica aerogel. Alkali catalyst was an extremely crucial factor for preparing silica aerogels. With the increase of the pH value from 7.5 to 10 the gelation time of the prepared aerogels was observed to decrease from 40 min to 2 min, and the shrinkage of aerogel sample decreased from 15.5% to 3.5%. The skeleton structure of the prepared silica aerogel gradually transformed from coarsened spherical to continuous irregularity finer structures with the increased concentration of CTAB. In addition, the prepared silica aerogel showed outstanding anti-adhesion property and superhydrophobic ability with a water contact angle (WCA) of 160.6 ± 1.3°.

The flower-like CuS hierarchical structures were synthesized by solvothermal method. The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared(FTIR) spectroscopy, UV–vis optical absorption spectroscopy and thermogravimetric analysis (TGA). The results demonstrated that the as-prepared flower-like CuS with the diameter of 1–5 um was pure hexagonal phase CuS and had well-defined flower-like structures. (1) The as-prepared CuS was proved to possess high photocatalytic performance with band gap of 1.45 eV. The degradation rate of Methylene blue (MB) was up to, 98.26%, 100% after 30 min under UV and visible irradiation. (2)The UPF of cotton fabric treated with CuS reached up to 174 compared with the original untreated fabric with the UPF 20.62. (3) The electromagnetic interference shielding effectiveness (EMI SE) of CuS coating was up to 27–31 dB when the content of CuS increased to 28.6%wt in the frequency of 300 KHz–3 GHz. Furthermore, the influence of reaction conditions on the morphology of the as-prepared CuS was investigated systematically and the possible formation mechanism of the CuS hierarchical structure was also proposed.

A facile method for the preparation of acid-resistant fabric with the fluoropolymer/SiO2 hybrid materials was presented. The polyester fabric was treated using a dip-dry technique and, subsequently, cured under high temperature. The results showed that the treated fabric displayed remarkable acid repellency with contact angles of 137.1°, 141.2°, and 139.5° for H2SO4 (80%), HCl (30%), and HNO3 (40%), respectively. The break force tests further confirmed the true potential of fluoropolymer/SiO2 hybrid materials to fabricate functional textile. We believe that this successful attempt offers an opportunity to fabricate acid-resistant fabric and advances the applications of protective clothing.

The flower-like CuS with hierarchical structures were synthesized by a solvothermal method. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, UV–vis optical absorption spectroscopy and thermogravimetric analysis (TGA) and ultraviolet transmittance analyzer labsphere were used to characterize the as-prepared products. The results of photocatalytic degradation of Methylene blue (MB) demonstrated that the as-prepared flower-like CuS possessed high photocatalytic performance in UV and visible range and its band gap was 1.45 eV. The degradation rate of MB by CuS with the absence of H 2 O 2 was 98.23% and 100% under xenon lamp and Mercury tungsten blended lamp for 30 min, respectively. And a new approach for ultraviolet (UV) protection of cotton fabrics treated by flower-like CuS microspheres was innovatively investigated and the results showed that flower-like CuS was a good UV resistant material.

Super-absorbent hydrogels (SAH) as an advanced material have drew great interest owing to their wide applications in various areas such as forestry, agriculture, sewage treatment and sanitary products. Swelling rate (SR) and water retention ratio (WRR) are usually the pivotal elements for its application. However, high SR of SAH with excellent WRR is rarely reported, which can be mainly due to unsuitable crosslinker. Here we show that a novel SAH with a dual stretchable single network was prepared through a free radical polymerization of AA and AM (acrylic acid-co-acrylic amide) monomer with self-made controllable vinyl hybrid silica nanoparticles (VSNPs) as crosslinker. Particularly, the dual stretchable single network was designed by the molecular chains grafting on the surface of VSNPs and hydrogen bonding on polymer chains, which can significantly improve the cross-linking density and enhance swelling performance. Therefore, SR of the SAH can reach up to 5066 g/g and remain over 70% moisture after exposed to the air for 3 days at 293k with humidity around 50%. This SAH also has an incomparable swelling property in other solution like urea, salt. The adsorption behavior of this SAH matches well with the Fickian diffusion model. Collectively, the design of this work opens a new way for the development of SAH with obviously enhanced swelling performance and water retention capacity in the biomaterial fields.

Cracks on a tunnel lining are commonly observed during in-site tunnel inspection. The cracks are generated owing to various reasons and can potentially further propagate as they are subjected to repeated dynamic train loads during the entire tunnel service life. The study investigated train-induced dynamic stress intensity factors (SIFs) of tunnel lining cracks by numerical simulations using the modal superposition approach and examined the effects of a wide range of factors. The methodology of the modal superposition approach was adopted and validated to determine dynamic SIFs. Subsequently, the coupled dynamic FE model was established to calculate train-induced SIFs of tunnel lining cracks and radiation damping owing to the infinite surrounding medium was determined. Finally, a parametric analysis was conducted to investigate the effects of crack location, crack depth, wave velocity of the surrounding medium, and material damping on dynamic SIFs of tunnel lining cracks subjected to metro train loads. The results demonstrate that the modal superposition approach can be employed to accurately and effectively calculate the train-induced dynamic SIFs of tunnel lining cracks when radiation damping is considered. The effects of crack location, crack depth, and wave velocity of the surrounding medium are significant, while the effect of material damping is not considerably evident. The maximum dynamic SIF significantly increases with crack depth, while it decreases with the wave velocity of the surrounding medium and material damping ratio. Cracks with greater depth in the poorer medium are more likely to propagate under dynamic train loads.

In this study, CuS/SiO2 composite modified aerogel was prepared by the incorporation of hollow spherical CuS into methyltrimethoxysilane-based SiO2 sol and modification with hexadecafluorodecyltriethoxysilane via acid-base catalyzed sol–gel reaction and drying under ambient pressure. The CuS/SiO2 composite modified aerogel was characterized by Fourier-transform infrared (FT-IR) spectrometry, scanning electron microscope (SEM), nitrogen gas adsorption and desorption and X-ray diffraction (XRD), respectively. The effects of CuS and fluorosilane concentration on density and porosity of aerogel, oleophobic and photocatalytic properties were evaluated. The results showed that structure and physical properties of aerogel had some effect by introducing CuS and fluorosilane, and the CuS/SiO2 composite modified aerogel with density of 0.146[Formula: see text]g/cm3 and specific surface area of 241[Formula: see text]m2/g achieved super-oleophobicity with oil contact angle of 152.8∘ and sliding angle of 10∘, and good photocatalytic properties for methylene blue.

Flower-like MnO2/reduced graphene oxide (RGO) nanocomposite with excellent microwave absorption properties was successfully fabricated via a facile hydrothermal method. SEM images showed that the flower-like MnO2 particles were grown on the surface of RGO nanosheets. The thickness of lower-like MnO2/RGO nanocomposite was 2.0 mm. The microwave absorption capacity of it was significantly enhanced compared with pure MnO2, the maximum reflection loss achieved −37.1 dB at 10.8 GHz, and the corresponding effective absorption bandwidth at −10 dB and 20 dB is 4.1 GHz (8.6–12.7 GHz) and 1.0 GHz (10.2–11.2 GHz), respectively. The unique flower-like framework structure of MnO2 plays a crucial role in the microwave absorption.

Anatase nano-TiO2 was synthesized by sol–gel method at a low temperature in this study. The effects of water amount and thermal crystallization treatment on the crystal structure and properties of nano-TiO2 were investigated. Crystal structure of nano-TiO2 was characterized by X-ray diffractometer and high-resolution transmission electron microscopy, and photocatalytic activity of nano-TiO2 was evaluated by the degradation rate of methylene blue solution. The results showed that with the increase of water amount, the crystal structure of TiO2 nanocrystalline transformed from amorphous crystal into anatase crystal and its crystallinity and photocatalytic activity increased. Compared with nano-TiO2 obtained by common drying at 150 °C, the TiO2 nanocrystallines obtained by steaming crystallization had higher crystallinity and better photocatalytic activity, and the degradation rate of methylene blue reached 90% after UV irradiation for 2 h. The prepared nano-TiO2 sols were coated onto the cotton fabrics to a...

A fluoropolymer/silica (FP/SiO2) organic–inorganic nanocomposite was synthesized by copolymerization of butyl acrylate (BA), methyl methacrylate (MMA), 2-hydroxyethyl acrylate (HEA), and dodecafluoroheptyl methacrylate (DFMA) based on vinyl nano-silica (V-SiO2) using emulsion polymerization. The V-SiO2 was prepared via water-based sol–gel reaction with vinyl trimethoxy silane (VTMS) as the precursor in the presence of the composite surfactant. The preparation of V-SiO2, influence of the composite surfactant on V-SiO2, effect of composite emulsifier on the properties of FP/SiO2, and the formation of the FP/SiO2 nanocomposite were analyzed. The resulting V-SiO2 and FP/SiO2 were characterized by particle size analyzer, transmission electron microscopy (TEM), Fourier-transform infrared spectrometry (FTIR), and X-ray photoelectron spectroscopy (XPS). The obtained FP/SiO2 nanocomposites were applied to coat onto the flexible polyester fabrics by dip-pad-cure process. The results showed that the V-SiO2 nanoparticles had been introduced into the FP/SiO2 nanocomposites and superhydrophobic polyester surfaces were achieved by the cooperation of the rough surface structure provided by the silica nanoparticles and the low surface energy caused by fluoropolymer.

The hexadecyltrimethoxysilane(HDTMS)-modified silica (H-SiO2) nanocomposite hydrosol was prepared via water-based sol-gel reaction with methyltrimethoxysilane (MTMS) and HDTMS as precursors under alkaline condition in the presence of surfactant. The influences of base catalyst amount and surfactant concentration on the particle size and distribution of H-SiO2 nanocomposite hydrosol were analyzed. The obtained H-SiO2 nanocomposite was characterized by particle size analyzer, Fourier-transform infrared spectrometry (FTIR), thermal gravimetric (TG) and field emission scanning electron microscopy (FE-SEM), respectively. The H-SiO2 nanocomposite hydrosol was applied to coat onto the cotton fabric sample via one-step process. The cooperative action of rough surface structure due to the silica nanoparticles and the low surface energy caused by long-chain alkylsilane in the H-SiO2 nanocomposite coating provided the treated cotton fabric with excellent superhydrophobicity.

Electromagnetic shielding polyester fabrics were prepared using carboxymethyl chitosan-palladium (CMCS-Pd) complexes as activation solution, followed by electroless nickel plating. CMCS-Pd complexes were prepared by the complexing adsorption between CMCS and Pd2+. The effects of reaction time and pH value on the adsorption of Pd2+ by CMCS were discussed. The maximum adsorption capacity was calculated as 4.27 mmol/g. CMCS-Pd complexes were characterized by ultraviolet (UV) spectrophotometer and Fourier transform-infrared (FTIR) spectroscopy. The induction time of electroless plating decreased gradually with the increase of Pd2+ concentration. The lowest surface resistance 125 mΩ/sq of the treated polyester fabric was obtained when Pd2+ concentration in CMCS-Pd complex was 1.5 g/l. The prepared polyester fabrics had excellent electromagnetic shielding effectiveness (SE) of 40–60 dB. The treated polyester fabrics were also characterized by scanning electron microscopy (SEM). Results showed that CMCS-Pd was effective to form an active catalyzed layer on polyester substrate and the 1.5 g/l Pd2+ was sufficient to initiate electroless nickel plating reaction. The CMCS-Pd complex activation and electroless nickel plating treatment caused small changes in the polyester fabrics’ tensile strength and air permeability.

In this paper, urchin-like MnO2/reduced graphene oxide (RGO) composite were successfully fabricated by a two-step method. The chemical structures, crystalline structures, and microscopic morphology were systematically characterized by Fourier transform infrared spectra (FTIR), x-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM). The electromagnetic parameters were measured by a vector network analyzer (VNA). SEM photographs revealed that reduced graphene oxide was firmly attached on the surface of urchin-like MnO2 with the size in the range of 3–5 μm. The electromagnetic parameters analysis demonstrated that combination of reduced graphene oxide and urchin-like MnO2 could obviously improve the impedance matching. The maximum reflection loss of urchin-like MnO2/reduced graphene oxide (RGO) composite is −32.4 dB at 17.2 GHz with a thickness of 1.5 mm, and the reflection loss peaks move to low frequencies with increase of the thickness of the composite sheet.

A novel visible-light flower-like CuS/graphene aerogels (CuS/GAs) photocatalyst has been synthesized via two-step solvothermal method. The CuS/GAs show outstanding synergies of adsorption and photocatalysis for anionic–cationic dyes degradation, which is attributed to unique network structure and excellent photoelectric properties of GAs. The high degradation ratio of Methyl orange and Methylene blue by synergy are 92% and 99.36%, which are about 4.1 and 3.2 times of that for pure CuS. The flower-like CuS/graphene aerogels resolve the low adsorption saturation problem of GAs and improve the photocatalytic performance of CuS, indicating CuS/GAs could be a promising photocatalyst for wastewater treatment.

The successful one-step preparation method of vinyl hybrid nanosilica (V-SiO2) hydrosols was studied. TheV-SiO2hydrosols were prepared via water-based sol-gel reaction with vinyl trimethoxy silane (VTMS) as the precursors under alkaline condition in the presence of composite surfactant. The formation mechanism of V-SiO2nanoparticles was explained. The size of V-SiO2nanoparticles could be adjusted by controlling the concentration of the composite surfactant and catalyst. Fourier transform infrared (FT-IR), transmission electron microscopy (TEM), Zetasizer Nano ZS Particle Size Analyzer were used to characterize V-SiO2nanoparticles. The obtained V-SiO2hydrosols are more convenient for preparation of polymer/SiO2nanocomposite.

The dispersion property of modified nano-TiO2 particles and its antibacterial properties on cotton fabrics were studied. The nano-TiO2 particles were modified with reactive groups (such as hydroxyl groups, amino groups and silica groups). The modified nano-TiO2 particles were characterized by particle size analyzer, Fourier transform-infrared spectroscopy and transmission electron microscopy. Besides, the chemical load technology of optimizing the nano-TiO2 on the textile fiber combined with fiber by grafting and cross-linking was studied. The results showed that the stability of nano-TiO2 sol was related to the concentration of the modifier and the pH values of the system. The washing fastness and the antibacterial property of the fabric treated by modified nano-TiO2 had been increased and the antibacterial property of treated fabric was also related to the concentration of the modifier. By determining the fiber’s crystallinity, as well as the fabric’s breaking strength and tear strength, the influence of the modified nano-TiO2 photocatalyst on the structural properties of cotton fiber was discussed.

Superhydrophobic cotton fabrics were prepared by the incorporation of silica nanoparticles and subsequent hydrophobization with hexadecyltrimethoxysilane (HDTMS). The silica nanoparticles were synthesized via sol–gel reaction with methyl trimethoxy silane (MTMS) as the precursor in the presence of the base catalyst and surfactant in aqueous solution. As for the resulting products, characterization by particle size analyzer, scanning electron microscopy (SEM), scanning probe microscopy (SPM), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA) were performed respectively. The size of SiO2 nanoparticles can be controlled by adjusting the catalyst and surfactant concentrations. The wettability of cotton textiles was evaluated by the water contact angle (WCA) and water shedding angle (WSA) measurements. The results showed that the treated cotton sample displayed remarkable water repellency with a WCA of 151.9° for a 5 μL water droplet and a WSA of 13° for a 15 μL water droplet.

A facile method to prepare superhydrophobic fluoropolymer/SiO2 nanocomposites coating on polyester (PET) fabrics was presented. The vinyl nanosilica (VSiO2) hydrosols were prepared via one-step water-based sol-gel reaction with vinyl trimethoxy silane as the precursors in the presence of the base catalyst and composite surfactant. Based on the VSiO2 hydrosol, a fluorinated acrylic polymer/silica (FAP/SiO2) nanocomposite was prepared by emulsion polymerization. The FAP/SiO2 nanocomposites were coated onto the polyester fabrics by one-step process to achieve superhydrophobic surfaces. The results showed that silica nanoparticles were successfully incorporated into the FAP/SiO2 nanocomposites, and a specific surface topography and a low surface free energy were simultaneously introduced onto PET fibers. The prepared PET fabric showed excellent superhydrophobicity with a water contact angle of 151.5° for a 5 μL water droplet and a water shedding angle of 12° for a 15 μL. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40340.