Mechanical and transport properties were assessed on wheat gluten films with a glycerol content of 25-40%, prepared by compression molding for 5-15 min at temperatures between 90 and 130 degrees C. Effects of storing the films up to 24 days, in 0 and 50% relative humidity (RH), were assessed by tensile measurements. The films were analyzed with respect to methanol zero-concentration diffusivity, oxygen permeability (OP), water vapor permeability (WVP), Cobb60 and sodium dodecyl sulfate (SDS) solubility coupled with sonication. The SDS solubility and methanol diffusivity were lower at the higher molding temperature. Higher glycerol content resulted in higher OP (90-95% RH), WVP, and Cobb60 values, due to the plasticizing and hygroscopic effects. Higher glycerol contents gave a lower fracture stress, lower Young's modulus, lower fracture strain, and less strain hardening. The mold time had less effect on the mechanical properties than mold temperature and glycerol content. The fracture stress and Young's modulus increased and the fracture strain decreased with decreasing moisture content.

For a number of applications, gluten protein polymer structures are of the highest importance in determining end‐use properties. The present article focuses on gluten protein structures in the wheat grain, genotype‐ and environment‐related changes, protein structures in various applications, and their impact on quality. Protein structures in mature wheat grain or flour are strongly related to end‐use properties, although influenced by genetic and environment interactions. Nitrogen availability during wheat development and genetically determined plant development rhythm are the most important parameters determining the gluten protein polymer structure, although temperature during plant development interacts with the impact of the mentioned parameters. Glutenin subunits are the main proteins incorporated in the gluten protein polymer in extracted wheat flour. During dough mixing, gliadins are also incorporated through disulfide‐sulfhydryl exchange reactions. Gluten protein polymer size and complexity in the mature grain and changes during dough formation are important for breadmaking quality. When using the gluten proteins to produce plastics, additional proteins are incorporated in the polymer through disulfide‐sulfhydryl exchange, sulfhydryl oxidation, β‐eliminations with lanthionine formation, and isopeptide formation. In promising materials, the protein polymer structure is changed toward β‐sheet structures of both intermolecular and extended type and a hexagonal close‐packed structure is found. Increased understanding of gluten protein polymer structures is extremely important to improve functionality and end‐use quality of wheat‐ and gluten‐based products.

Tough fibrous membranes for smoke filtration have been developed from recycled polyethylene terephthalate (PET) bottles by solution electrospinning. The fibre thicknesses were controlled from 0.4 to 4.3 mm by adjustment of the spinning conditions. The highest fibre strength and toughness were obtained for fibres with an average diameter of 1.0 mm, 62.5 MPa and 65.8 MJ m À3 , respectively. The Xray diffraction (XRD) patterns of the fibres showed a skewed amorphous halo, whereas the differential scanning calorimetry (DSC) results revealed an apparent crystallinity of 6-8% for the 0.4 and 1 mm fibres and 0.2% crystallinity for the 4.3 mm fibres. Heat shrinkage experiments were conducted by exposing the fibres to a temperature above their glass transition temperature (T g ). The test revealed a remarkable capability of the thinnest fibres to shrink by 50%, which was in contrast to the 4.3 mm fibres, which displayed only 4% shrinkage. These thinner fibres also showed a significantly higher glass transition temperature (+15 C) than that of the 4.3 mm fibres. The results suggested an internal morphology with a high degree of molecular orientation in the amorphous segments along the thinner fibres, consistent with a constrained mesomorphic phase formed during their rapid solidification in the electric field. Air filtration was demonstrated with cigarette smoke as a model substance passed through the fibre mats.The 0.4 mm fibres showed the most effective smoke filtration and a capacity to absorb 43Â its own weight in smoke residuals, whereas the 1 mm fibres showed the best combination of filtration capacity (32Â) and mechanical robustness. The use of recycled PET in the form of nanofibres is a novel way of turning waste into higher-value products.

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Recent progress in the development of polyethylene/metal-oxide nanocomposites for extruded high-voltage direct-current (HVDC) cables with ultrahigh electric insulation properties is presented. This is a promising technology with the potential of raising the upper voltage limit in today's underground/submarine cables, based on pristine polyethylene, to levels where the loss of energy during electric power transmission becomes low enough to ensure intercontinental electric power transmission. The development of HVDC insulating materials together with the impact of the interface between the particles and the polymer on the nanocomposites electric properties are shown. Important parameters from the atomic to the microlevel, such as interfacial chemistry, interfacial area, and degree of particle dispersion/aggregation, are discussed. This work is placed in perspective with important work by others, and suggested mechanisms for improved insulation using nanoparticles, such as increased charge trap density, adsorption of impurities/ions, and induced particle dipole moments are considered. The effects of the nanoparticles and of their interfacial structures on the mechanical properties and the implications of cavitation on the electric properties are also discussed. Although the main interest in improving the properties of insulating polymers has been on the use of nanoparticles, leading to nanodielectrics, it is pointed out here that larger microscopic hierarchical metal-oxide particles with high surface porosity also impart good insulation properties. The impact of the type of particle and its inherent properties (purity and conductivity) on the nanocomposite dielectric and insulating properties are also discussed based on data obtained by a newly developed technique to directly observe the charge distribution on a nanometer scale in the nanocomposite.

• Coronavirus pandemic have made facemasks worldwide healthcare essentials • Shortage of masks exposes medical personnel and the public to the risk of infection • Utilisation of sustainable raw materials to develop bio-based masks is needed • Electrospun and compression moulded gluten can be used to develop biobased masks • Gluten masks can be made flame retardant by adding b10 wt% of lanosol.

Recently, hydrogel-based conductive materials and their applications as smart wearable devices are paid tremendous attention due to their high stretchability, flexibility, and excellent biocompatibility. Compared with single functional conductive hydrogel,...

The effect of using different zinc salts on size, morphology and photoluminescence of ZnO nanoparticles in high-yield aqueous precipitation synthesis.