测试条件对环氧树脂损耗因子和玻璃化转变温度的影响

Influence of Testing Conditions on Loss Factor and Glass Transition Temperature of Epoxy

采用动态力学分析(DMA)研究环氧树脂,分析了扫描频率、加载模式和升温速率对环氧树脂损耗因子和玻璃化转变温度的影响。结果表明:扫描频率越大,所测得的玻璃化转变温度也越高,损耗因子峰值也越高,峰宽也越宽,玻璃化转变区域也越大;升温速率越快,玻璃化转变温度也越高,损耗因子峰值越低;利用Arrhenius公式计算得到环氧树脂玻璃化转变所需要的活化能△E,在拉伸模式下的△E比弯曲模式下的大很多。

Epoxy resin was studied by using dynamical mechanics analysis （DMA）. The influences of the loading frequency, loading mode and heating rate on the loss factor and glass transition temperature of epoxy were analyzed. The results show that the higher loading frequency is chosen, the higher glass transition temperature is obtained, the peak of loss factor becomes higher and wider, and the region of the glass transition appears wider. The faster heating rate is chosen, the higher glass transition temperature is obtained, and the lower peak of loss factor is got. The activation energies, △E, of glass transition in the different loading modes are calculated by Arrhenius equation. The activation energy in the tensile loading mode is much larger than the one in the bending loading mode.