纳米SiO2/环氧树脂复合材料的电热性能研究

Study on Electrothermal Properties of Nano-SiO2/Epoxy Resin Composites

为研究纳米二氧化硅(nano-SiO2)掺杂对环氧树脂电热性能的影响,以nano-SiO2改性双酚A型环氧树脂为研究对象,通过电、热两个角度对不同nano-SiO2含量下环氧树脂复合材料的介电性能、热稳定性进行测试。结果表明,环氧树脂复合材料在3%nano-SiO2含量时达到较好的介电性能,其中相对介电常数(εr)、介电损耗角正切(tanδ)达到最小值,相比纯环氧树脂分别降低14.7%和19.3%,介电强度达到最大值22.9 kV/mm,提升约40%。对3%nano-SiO2含量环氧树脂进行改性前后热氧老化对比研究,据失重速率及介电参数变化趋势,可将老化发展分为起始期、发展期、爆发期,老化寿命延长约25%,为提高环氧树脂绝缘能力方案设计提供参考。

In order to study the effect of nano-SiO2 doping on the electrothermal properties of epoxy resin,nano-SiO2 modified bisphenol A epoxy resin was used as the research object.The dielectric properties and thermal stability of epoxy resin with different nano-SiO2 content were tested by electric and thermal angles.The results show when the content of nano-SiO2 achieves 3%,the composites could achieve better dielectric properties.The relative dielectric constant(εr)and the dielectric loss tangent(tanδ)could reach a minimum value,which has decreased 14.7%and 19.3%,respectively.And the dielectric strength could reach a maximum value of 22.9 kV/mm,which has increased about 40%.According to the comparison of thermal oxygen aging before and after evolution modification of epoxy resin with 3%of nano-SiO2,based on the trend of weight loss rate and dielectric parameter,the aging development can be divided into initial period,development period and outbreak period,and the aging life is extended about 25%.It provides reference for improving the design of epoxy resin insulation.