Zirconium diboride (ZrB2) powder was synthesized at a low temperature via a molten‐salt‐mediated reduction route using ZrO2, Na2B4O7 and Mg powders as starting raw materials. By using appropriately excessive amounts of Mg and Na2B4O7 to compensate for their evaporation losses, ZrO2 could be completely converted into ZrB2 after 3 h at 1200°C. In addition, the formation of undesirable Mg3B2O6 could be effectively avoided. As‐prepared ZrB2 powders were phase pure, 300–400 nm in size and generally well dispersed. SEM images showed that to a large extent the reactively formed ZrB2 retained the morphology and size of the starting ZrO2. The salt melt formed from MgCl2 and Na2B4O7 at test temperatures is believed to be responsible for the reduced synthesis temperature and good dispersion of the final ZrB2 product powder.

Phase pure titanium diboride (TiB2) powder of 100‐200 nm was synthesized from TiO2 and B2O3 using a molten‐salt‐assisted magnesiothermic reduction technique. The effects of salt type, Mg amount, reaction temperature, and TiO2 raw materials on the synthesis process were examined and the relevant reaction mechanisms discussed. Among the three chloride salts (NaCl, KCl, and MgCl2), MgCl2 showed the best accelerating‐effect. To synthesize phase pure TiB2, 20 mol% excessive Mg had to be used to compensate for the evaporation loss of Mg. Particle shape and size of raw material TiO2 showed little effect on the formation of TiB2 and its shape and size, suggesting that relatively cheaper and coarser TiO2 raw materials could be used for low‐temperature synthesis of TiB2 fine particles. The “dissolution‐precipitation” mechanism governed the overall molten salt synthesis process.

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Osteoarthritis (OA) is a disease that leads to the damage of subchondral bone. To treat OA, patients can have surgery to implant biomaterials into the damaged area. In this research, biomaterials of 3D porous scaffolds were fabricated by the use of air microbubbles for subchondral bone formation proposed for OA surgery. Microbubbles were generated in a polyvinyl alcohol solution at various air flow rates of 20 (F20), 100 (F100), 200 (F200), and 300 (F300) cc min−1. Molecular organization, structure, and morphology of the scaffolds were characterized and observed by Fourier transform infrared spectroscopy, a differential scanning calorimeter, and a scanning electron microscope, respectively. Physical and mechanical properties based on swelling behavior and compressive strength of the scaffolds were also evaluated. Biological performance by means of osteoblast proliferation, protein synthesis, and alkaline phosphatase activity of the scaffolds were studied. The scaffolds showed molecular organization via interaction of –OH and C = O. They had residual water in their structures. The scaffolds exhibited a morphology of a spherical-like cell shape with small pores and a rough surface produced on each cell. Each cell was well connected with the others. The cell size and porous structure of the scaffolds depended significantly on the flow rate used. The molecular organization, structure, and morphology of the scaffolds had an effect on their physical and mechanical properties and biological performance. F100 was found to be an optimum scaffold offering a molecular organization, structure, morphology, physical and mechanical properties, and biological performance which was suitable for subchondral bone formation. This research deduced that the F100 scaffold is promising for OA surgery.

Natural rubber foams are currently produced by the two well-known processes of Dunlop and Talalay. Dunlop process, however, requires a high-speed Hobart Mixer to generate a high bubble-volume, while Talalay is complexity and expensive technique. Here, a simple and inexpensive technique for rubber foam production was introduced. The process involved air flowing with a constant flow rate through a porous diffuser, firmly connected to the bubble column containing compound latex, to generate a high bubble-volume. Microstructure of the as-produced rubber foams was examined using a scanning electron microscope (SEM), in comparison with that of the purchased Dunlop foam. Spherical cell shape with a uniform interconnected-cell structure was gained from the bubbled foams, while fractured-cell structure was obtained from the Dunlop foam.