摘要
对比研究了3种不同片径微米级和一种纳米级片状氮化硼对环氧树脂流变和导热性能的影响。结果表明:加入大片径微米级氮化硼更有利于提高环氧树脂的导热性能,并使改性后环氧树脂具有较低的黏度。当加入质量分数为30%的微米级氮化硼PT110和PT120时,环氧树脂的导热系数可由0.18W·m^-1·K^-1提高到1.01W·m^-1·K^-1和0.94W·m^-1·K^-1。相对微米级氮化硼,纳米级氮化硼对环氧树脂导热性能的提高并没有优势,且显著增加改性树脂的黏度。利用多种理论模型对不同氮化硼改性环氧树脂的导热系数进行模拟,其中,几何平均模型对改性环氧树脂导热系数的预测值与试验值较为吻合。优化后的微米级氮化硼改性环氧树脂与未改性树脂相比,具有几乎相同的固化反应温度和玻璃化转变温度,弯曲模量显著提高,但弯曲强度明显下降。
In this study,the effects of three micro-scale and one nano-scale boron nitride sheets on the rheological properties and thermal conductivity of epoxy resins were investigated.The results show that the addition of large microscale boron nitride sheets is more beneficial to improve the thermal conductivity of resulting epoxy composites,and has relatively less influence on the viscosity.When 30%micro-scale boron nitride sheets PT110 and PT120 are added,the thermal conductivity values of modified epoxy resins increase from 0.18W·m^-1·K^-1 to 1.01W·m^-1·K^-1 and 0.94W·m^-1·K^-1,respectively.Compared with micro-scale boron nitride sheets,the nano-scale boron nitride sheets do not exhibit superiority to improve the thermal conductivity of epoxy resins,but can cause a significant increase in viscosity.The thermal conductivity of epoxy composites modified by different boron nitride were simulated by various theoretical models.Among them,the thermal conductivity values of modified epoxy resins predicted by the geometrical mean model are close to the experimental values.Compared with the unmodified epoxy resins,the epoxy composites modified by optimized boron nitride sheets shows almost the same curing temperatures and glass transition temperature,significantly increased flexural modulus but dramatically decreased flexural strength.
作者
郑襄丹
魏毅
刘卫平
刘万双
ZHENG Xiangdan;WEI Yi;LIU Weiping;LIU Wanshuang(Center for Civil Aviation Composites,Donghua University,Shanghai 201620,China)
出处
《航空制造技术》
2020年第18期65-73,共9页
Aeronautical Manufacturing Technology
基金
上海自然科学基金(18ZR1400700)。
关键词
环氧树脂
复合材料
氮化硼
高导热
力学性能
Epoxy resins
Composites
Boron nitride
High thermal conductivity
Mechanical properties
