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Adopting magnetron sputtering continuous automatic production line equipment for industrial production, polyester fabrics as the substrates were coated with nano-Ag/TiO2 composite films prepared by direct current sputtering method and direct current/radio frequency reactive sputtering method, respectively. The microstructure of Ag/TiO2 composite films deposited on the surface of the fabrics was dense and uniform. Structural colors were generated on the surface of the fabrics coated with the composite films and the coloring mechanism was consistent with the single-layer film interference principle. The color fastness, mechanical properties, comfortable properties were not significantly changed and had better antistatic property, anti-ultraviolet property, and antibacterial property compared with the original polyester fabrics. Therefore, the multi-functional and structurally colored fabrics can be prepared by magnetron sputtering technology, and can achieve industrial production, and have wide application prospects in apparel, home textile, and so on. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile-based pre-oxidized fibers with improved thermal stability, flame retardant, and mechanical properties were made from the pristine polyacrylonitrile fibers through chemical pretreatment followed by pre-oxidation in air. The morphological structure of the polyacrylonitrile-based pre-oxidized fibers was investigated by Fourier transfer infrared spectra, X-ray diffraction, scanning electron microscopy, and X-ray energy dispersive spectrometer. The changes of characteristic functional groups and chemical compositions confirmed the successful modification of the polyacrylonitrile fibers during pre-treatment. The grooves and cracks on the surface of polyacrylonitrile-based pre-oxidized fibers were remarkably decreased in comparison with that of pristine polyacrylonitrile fibers. The evolution of crystalline structure of the polyacrylonitrile fibers proved the occurrence of cyclization reactions during pre-oxidation. Meanwhile, thermal stability, flame retardant, and mechanical properties of polyacrylonitrile-based pre-oxidized fibers were also investigated by thermogravimetric analyzer, oxygen index meter, micro combustion calorimeter, and single fiber tensile tester, respectively. The results demonstrated that the polyacrylonitrile-based pre-oxidized fibers initially pre-treated by hydroxylamine hydrochloride, followed by monoethanolamine, had a high limiting oxygen index of 40.1 and breaking strength of 2.03 cN/dtex. The peak of heat release rate and total heat release of polyacrylonitrile-based pre-oxidized fibers decreased significantly while its charred residues increased, contributing to the improved flame retardant property. [ABSTRACT FROM AUTHOR]

A series of novel capric–palmitic–stearic acid ternary eutectic/polyacrylonitrile/carboxyl purified multi‐walled carbon nanotubes (CA–PA–SA/PAN/MWNTs‐COOH) form‐stable phase change composite fibrous membranes (PCCFMs) were fabricated by electrospinning and physical absorption methods. In these form‐stable PCCFMs, the CA–PA–SA ternary eutectic was served as phase change material for thermal energy storage, and the loaded MWNTs‐COOH was acted as thermal conductivity enhancement filler to improve heat transfer rates, as well as electrospun PAN/MWNTs‐COOH fibrous membranes with different weight fractions of MWNTs‐COOH (i.e., 5, 10, and 20 wt%) were used as supporting materials to provide structural strength and prevent liquid leakage of melted CA–PA–SA ternary eutectic. The morphological structure and thermal performances were investigated and analyzed. The images of scanning electron microscopy showed that the CA–PA–SA ternary eutectic was uniformly embedded and dispersed into the three‐dimensional porous network structure of electrospun PAN/MWNTs‐COOH fibrous membranes. Thermal performance tests suggested that the melting and freezing times of the CA–PA–SA/PAN/MWNTs‐COOH form‐stable PCCFMs with the addition of 10 wt% MWNTs‐COOH were significantly shorten by about 52% and 56% in comparison with those of the CA–PA–SA/PAN form‐stable PCCFMs. Their phase change temperatures and enthalpies were about 7°C–32°C and 130–138 kJ/kg, respectively. POLYM. ENG. SCI., 59:E403–E411, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Environmental hormones such as bisphenol A have attracted enormous attention due to their potential threat to humans and environment. Herein, we synthesized a BC/MIL-53 (Al)-F127 composite membrane by the vacuum filtration method with a mesostructure metal–organic framework MIL-53 (Al)-F127 and bacterial cellulose as the substrate. The BC/MIL-53 (Al)-F127 composite membrane exhibited efficient adsorption of bisphenol A in aqueous solution. The results exhibited that 94% of bisphenol A could be adsorbed in approximately 120 min, and the equilibrium sorption amounts of bisphenol A reached approximately 8.3 mg/g. Meanwhile, the mechanism of adsorption was explored. The optimum pH and temperature for the adsorption of bisphenol A were 6 and 40°C, respectively. The removal efficiency of bisphenol A was maintained at 90% after five repeated cycles, indicating the advantage to separate freely without a complex filtration system. The results of adsorption indicated that the BC/MIL-53 (Al)-F127 membrane has great potential in the aspect of the sewage treatment as a prospective sorbent. [ABSTRACT FROM AUTHOR]

In this work, a fast water-responsive shape memory hybrid polymer based on thermoplastic polyurethane (TPU) was prepared by crosslinking with hydroxyethyl cotton cellulose nanofibers (CNF-C) and multi-walled carbon nanotubes (CNTs). The effect of CNTs content on the electrical conductivity of TPU/CNF-C/CNTs nanocomposite was investigated for the feasibility of being a strain sensor. In order to know its durability, the mechanical and water-responsive shape memory effects were studied comprehensively. The results indicated good mechanical properties and sensing performance for the TPU matrix fully crosslinked with CNF-C and CNTs. The water-induced shape fixity ratio (Rf) and shape recovery ratio (Rr) were 49.65% and 76.64%, respectively, indicating that the deformed composite was able to recover its original shape under a stimulus. The TPU/CNF-C/CNTs samples under their fixed and recovered shapes were tested to investigate their sensing properties, such as periodicity, frequency, and repeatability of the sensor spline under different loadings. Results indicated that the hybrid composite can sense large strains accurately for more than 103 times and water-induced shape recovery can to some extent maintain the sensing accuracy after material fatigue. With such good properties, we envisage that this kind of composite may play a significant role in developing new generations of water-responsive sensors or actuators. [ABSTRACT FROM AUTHOR]

Acid Red 138, as a weak acid azo dye with a long alkyl chain, is widely used for protein fiber dyeing while it cannot dissolve in supercritical carbon dioxide. The objective of this study is to investigate the solubility of Acid Red 138 with water at the temperatures of 353.15, 363.15, 373.15, 393.15 and 413.15 K and over a pressure range of 20 to 26 MPa. The test results revealed that the phase equilibrium of water and Acid Red 138 was affected by the competition between pressure and density of supercritical carbon dioxide. Furthermore, the experimental solubilities were correlated by three types of density-based model. Good agreement with less than 3.36% of average absolute relative deviation between the calculated and the experimental data of water was achieved. In addition, the Chrastil model, Mendez-Santiago-Teja model and Sung-Shim model exhibited excellent correlation results for Acid Red 138 solubilities with the AARD values of 8.58%, 6.06% and 5.19%. Better understanding of the solubility behavior of Acid Red 138 in supercritical carbon dioxide displays potential for developing a microemulsion system for the eco-friendly dyeing of natural fibers., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)