Evaluation of the Effect of Different Nano-Size of WO3 on the Structural and Mechanical Properties of HDPE

The new category of high-density polyethylene HDPE/WO 3 was synthesized via compression molding technique. Various amounts (10, 15, 25, and 35 wt%) of bulk micro-sized WO 3 (Sample A) and two selected WO 3 nanoparticles 45 nm (Sample B) and 24 nm (Sample C) obtained through the mechanical process were used as filler to HDPE. The prepared composites with filler 15 and 35 wt% were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), scanning electron microscope, and energy-dispersive X-ray. XRD and FTIR results exhibited that filler does not affect either the crystal or the chemical structure of HDPE, confirming the adsorption of the filler on the surface polymer matrix. The morphology exhibited a more uniform dispersion of WO 3 nanoparticles in the HDPE polymer matrix at low filler weight fractions. The mechanical properties of the composites at all filler contents were investigated using Vickers microhardness and tensile stress–strain tests. The variation of Vickers microhardness H v showed a reverse indentation size effect (RISE) and exhibited a noticeable increase with increasing the WO 3 NPs(C) filler loading up to 25 wt%. The tensile test revealed an increase in Young’s modulus, ultimate tensile strength, and yield stress by the addition of either WO 3 nanoparticles (B or C) to 25 wt%. Otherwise, any further increase in nano wt% filler induced a decrease in the elongation at break. This improvement, deduced in the mechanical properties of the nanocomposites, suggests promising applications in radiation shielding and industry such as coating, barriers, catalysis, photo corrosion, and photothermal conversion.