In this study, hydrous (Zn₃B₆O₁₂·3.5H₂O) and anhydrous (ZnB₂O₄) forms of zinc borates were synthesized at 150 and 175°C under moderate pressure conditions (85 and 150 psi, respectively). Synthesized zinc borates were controllably incorporated (1, 5, and 10 wt%) in epoxy resin to prepare their nanocomposites. The flame‐retardant and mechanical properties of these nanocomposites were determined and compared in terms of their flame spread testing, smoke density, limiting oxygen index, and flexural strength. Superior properties in terms of flame retardancy were observed for epoxy composites containing hydrous filler as compared to anhydrous zinc borates. Although flexural strength was observed to be decreased with increasing filler concentration, the marked drop is lower for composites with hydrous zinc borate as compared to the anhydrous one. The variations in flame‐retardant and mechanical properties of composites with both types of fillers are related to their morphological (field emission scanning electron microscopy), X‐ray diffraction (XRD) analysis, Fourier Transform Infrared (FTIR), differential scanning calorimetry, and thermogravimetry analysis and explained with condensed phase mechanism.

中文翻译：

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水合无水硼酸锌填料，用于调节环氧纳米复合材料的阻燃性

在这项研究中，含水（Zn ₃ B ₆ O ₁₂ ·3.5H ₂ O）和无水（ZnB ₂ O ₄在中等压力条件下（分别为85和150 psi）在150和175°C合成硼酸锌。将合成的硼酸锌可控地掺入（1、5、10重量％）到环氧树脂中以制备其纳米复合材料。确定了这些纳米复合材料的阻燃性和机械性能，并根据它们的火焰蔓延测试，烟气密度，极限氧指数和抗弯强度进行了比较。与无水硼酸锌相比，含水填料的环氧复合材料在阻燃性方面具有优异的性能。尽管观察到弯曲强度随填料浓度的增加而降低，但与无水硼酸锌相比，含水硼酸锌的复合材料的显着下降较低。