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Monoclinic scheelite-type BiVO4 is currently considered as one of the most promising non-titania photocatalysts, wheras tetragonal zircon-type BiVO4 is still poorly understood. Herein, a new and simple synthetic approach was applied and nanostructured single-phase zircon-type BiVO4 was successfully prepared by a controllable ethylene-glycol colloidal route. In addition, nanostructured monoclinic scheelite-type BiVO4 powders were also fabricated through annealing of the as-prepared samples. A comparative study of the two BiVO4 polymorphs was conducted and it turned out that the novel synthetic approach had a significant impact on porosity and photocatalytic performance of zircon-structured BiVO4. All the prepared materials, as-prepared and annealed, were meso-porous, while measured values of specific surface area of some zirconstructured samples (∼34 m 2 /g) were ∼7 times higher than those reported thus far for this phase. Interestingly, for the first time, zircon-type BiVO4, previously considered to be a poor photocatalyst, exhibited a better overall performance in degradation of methyl orange compared to monoclinic scheelite-type BiVO4. Hence, it could be expected that the here-presented synthesis and observations will both arouse interest in scarcely studied tetragonal zircon-type BiVO4 and facilitate as well as speed up further research of its properties.

The powder recycled rubber (PRR) can be used as a filler and a modifier for elastomeric materials and asphalt. Composites based on elastomers and recycled rubber powders are a serious challenge for the environment. The main goal of this paper was to study the effect of rubber powder on the mechanical properties of elastomeric composites based on three precursors of the network. Triple blends were prepared using non‐polar natural rubber (NR), polyisoprene rubber (BR), and styrene‐butadiene rubber (SBR) (mass ratio 40/40/20). In all rubber compounds, the carbon black (CB)/PRR mass ratio is constant (60). Samples were prepared using two roll mill. The characteristics of hardening (optimum cure time, scorch time, minimum and maximum torque) of rubber mixtures were tested. Tensile strength, modulus at 100% elongation and elongation at break are decreasing with PRR ratio is increasing. It is due to poor adhesion of PRR into NR/BR/SBR/CB matrix. The thermal degradation temperature shifts to a higher temperature up to 5 phr of PRR in NR/BR/SBR/CB rubber blends. Fourier‐transform infrared spectra of NR/BR/SBR/CB/PRR samples show that the absorption bands shifted 7–15 cm−1 to higher wavenumbers and confirmed rubber–filler interaction. Morphology was assessed by scanning electron microscopy. POLYM. COMPOS., 40:1307–1314, 2019. © 2018 Society of Plastics Engineers

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