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Cellulose is a promising alternative material as a sorbent for the removal of pollutants. The availability of hydroxyl groups on cellulose allows for the application of various modification reactions for the development of novel sorbents with different functional groups. In this work, a cellulose sorbent modified with N-methyl-glucamine was prepared and tested for the removal of boron. A batch adsorption process was used to further explore the boron sorption kinetics, isotherms, thermodynamics, mechanism, and reuse of the prepared sorbent. It was found that the optimum sorbent dose for boron removal was 0.2 g/25 mL. Moreover, the initial pH of the solution was found to affect the removal rate and was found to be ≥ 4. The sorption of boron reached equilibrium within 60 min. The maximum sorption capacity was calculated to be 4.7 mg B/g sorbent. The sorption process was found to be exothermic and the negative value of ∆S in the range of 30–60 °C is related to a decrease in randomness at the solid/solution interface during the sorption of boron on the sorbent. The sorption/regeneration experiments have shown that the removal rate of the sorbent remains the same over 5 cycles. [ABSTRACT FROM AUTHOR]

In this study, a novel three functional chain extender (TATATRIOL) was synthesized from the reaction of 1,3,5-tri(prop-2-en-1-yl)-1,3,5-triazinane-2,4,6-trione (TATA) with 2-sulfanylethanol. Then new thermoplastic polyurethanes (TPUs) were synthesized by a one-step bulk polymerization from the reaction of 1,1′-methanediylbis(4-isocyanatocyclohexane) (HMDI), a poly(ethylene adipate) based polyester polyol and a chain extender. Butane-1,4-diol (BD) and the newly synthesized monomer, TATATRIOL, were used as chain extenders. The effects of TATATRIOL on the properties of the TPU were investigated and compared to those of the TPU prepared with BD. The TPUs which derived from the sulfur containing chain extender displayed lower modulus and high elongation at break values than the analogous TPUs derived from BD. Moreover sulfur containing TPUs exhibited higher thermal stability. [ABSTRACT FROM AUTHOR]

Poly(vinylidene fluoride) (PVDF)/sodium hydrogen carbonate (NaHCO)-based microporous polymer membranes were prepared by salt leaching. In this study, lithium-trifluoromethane sulfonate (LiCFSO) was used by dissolving it in solvents like propylene carbonate (PC), dimethyl carbonate (DMC), and diethylene carbonate (DEC). Microporous polymer electrolytes (MPE) were obtained from their porous polymer membranes when immersed in 0.1 M LiCFSO in a mixture of PC/DMC/DEC (2:2:1) electrolyte solution. The membranes were characterized by electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), chronopotentiometry (CP), chronocoulometry (CC), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The electrochemical stability window of the membrane has been evaluated with LSV using the triple electrode system. Ac conductivities of the Li salt containing membranes were found to be 1.34 × 10 S cm (GPE100) and 2.69 × 10 S cm (GPE25). [ABSTRACT FROM AUTHOR]

In this study, polypyrrole-clay (PPy-clay) composites were prepared by the in situ chemical oxidative polymerisation of pyrrole in the presence of clay. The chemical structures of the composites were characterised by FTIR and XRD analysis. The thermal properties of these novel composites were analysed by TGA and DSC measurements. Glass-transition temperatures and char yields increased with the increase in clay content in the nanocomposites. The interactions between PPy and clay were mainly between polypyrrole and the layers of clay. It was observed that, as the amount of clay in the composites increased, the dielectric permittivity decreased while the dielectric conductivity of the composite materials increased. [ABSTRACT FROM AUTHOR]

In this study, photocurable fluorine-containing coatings were prepared via thiol-ene click chemistry and an in situ sol-gel method. MPTMS was used as a coupling agent to perform both the thiol-ene click reaction and the sol-gel reactions. PFOTES was utilized for the preparation of fluorine-containing coatings. The addition of fluorine and silica showed a significant impact on the properties of the coatings. The addition of silica greatly enhanced the mechanical properties of the coatings. As the fluorine and silica contents were increased in the formulations, flame retardancy, hydrophobicity, and oleophobicity of the coatings increased. High char yields were obtained for the silica- and fluorine-containing samples. Furthermore, the effect of AlO nanoparticles on the properties of the hybrid coatings was investigated. [ABSTRACT FROM AUTHOR]