The combined effects of phosphorous-jointed epoxidized soybean oil and rice husk–based silica on the flammability and mechanical properties of epoxy resin were examined in detail. The chemical structures of the epoxidized soybean oil, phosphorous-jointed epoxidized soybean oil, and rice husk–based silica were confirmed using Fourier transform infrared spectroscopy and proton nuclear magnetic resonance. Many characteristics of the obtained composite materials were examined, such as the tensile properties, impact strength, flexural strength, critical stress intensity factor (KIC), dynamic mechanical analysis, and flammability. The incorporation of both 10 phr phosphorous-jointed epoxidized soybean oil and 20 phr rice husk–based silica into the epoxy resin yielded the optimum values of the flexural strength, tensile strength, impact strength, and KIC, with increases of 87.78%, 67.23%, 109.34%, and 111.32%, respectively, compared with pristine samples. The limiting oxygen index increased from 23.1% to 29.3%, the peak heat-release rate decreased by up to 37.2%, and the sample satisfied the UL94 V-0 rating.

中文翻译：

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磷结合环氧化大豆油和稻壳基二氧化硅作为改善环氧树脂机械性能和阻燃性的新型添加剂

详细研究了磷接环氧化大豆油和稻壳基二氧化硅对环氧树脂可燃性和机械性能的综合影响。使用傅里叶变换红外光谱和质子核磁共振确认了环氧化大豆油、磷结合环氧化大豆油和稻壳基二氧化硅的化学结构。检查了所得复合材料的许多特性，如拉伸性能、冲击强度、弯曲强度、临界应力强度因子 (KIC)、动态力学分析和可燃性。将 10 份含磷环氧化大豆油和 20 份稻壳基二氧化硅掺入环氧树脂中，产生了弯曲强度、拉伸强度、冲击强度和 KIC 的最佳值，与原始样本相比，分别增加了 87.78%、67.23%、109.34% 和 111.32%。极限氧指数从23.1%提高到29.3%，峰值放热率降低37.2%，样品满足UL94 V-0等级。