A solid polymer electrolytes (SPE) comprising blend of poly(ethylene oxide; PEO) and epoxidized natural rubber as a polymer host and LiCF 3 SO 3 as a dopant were prepared by solution-casting technique. The SPE films were characterized by field emission scanning electron microscopy to determine the surface morphology, X-ray diffraction, and differential scanning calorimeter to determine the crystallinity and thermogravimetric analysis to confirm the mass decrease caused by loss of the solvent. While the presence of the complexes was investigated by reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Electrochemical impedance spectroscopy was conducted to obtain ionic conductivity. Scanning electron microscopy analysis showed that a rough surface morphology of SPE became smoother with addition of salt, while ATR-FTIR spectroscopy analysis confirmed the polymer salt complex formation. The interaction occurred between the salt, and ether group of polymer host where the triple peaks of ether group in PEO merged and formed one strong peak at 1,096 cm −1 . Ionic conductivity was found to increase with the increase of salt concentration in the polymer blend complexes. The highest conductivity achieved was 1.4× 10 −4 Scm −1 at 20 wt.% of LiCF 3 SO 3 , and this composition exhibited an Arrhenius-like behavior with the activation energy of 0.42 eV and the preexponential factor of 1.6×10 3 Scm −1 .

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This review (with 99 refs.) summarizes the progress that has been made in colorimetric (i.e. spectrophotometric) determination of organophosphate pesticides (OPPs) using gold and silver nanoparticles (NPs). Following an introduction into the field, a first large section covers the types and functions of organophosphate pesticides. Methods for colorimetric (spectrophotometric) measurements including RGB techniques are discussed next. A further section covers the characteristic features of gold and silver-based NPs. Syntheses and modifications of metal NPs are covered in section 5. This is followed by overviews on enzyme inhibition-based assays, aptamer-based assays and chemical (non-enzymatic) assays, and a discussion of specific features of colorimetric assays. Several Tables are presented that give an overview on the wealth of methods and materials. A concluding section addresses current challenges and discusses potential future trends and opportunities.

A family of novel sulfonate based homopolymers has been prepared by partially replacing sodium cations with different types of ionic liquid ammonium counter-cations, leading to an increased degree of decoupling of the conductivity from the glass transition of the ionomers.

Military systems have become more complex, and the development of future advanced materials for defence applications have received much attention. Nanocellulose has been identified as a 'super versatile material' that...

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The adsorption and desorption of contaminants by nanocellulose.