聚酯改性环氧复合体系的介电性能

用共混复合的方法，加入不同量的聚酯，对环氧树脂进行改性，所得到的聚酯改性环氧复合体系在常温下具有优良的介电性能，介电损耗为１０＾－３个数量级。研究了复合体系的组成、电场频率及测试温度与介电损耗的关系，通过聚酯加入量对介电常数及弹性模量的影响，指出介电损耗与聚酯的加入量有较大关系，在加入８￣１６ｇ聚酯的范围内出现峰值。介电损耗随电场频率的升高而下降，且随温度的变化比较复杂，在９０℃￣１５０℃范围内出

Dielectric Properties of the Modified Epoxy Resins by Polyester

The modified epoxy resins by polyester (PET), which is prepared by a blending process, have excellent dielectric properties. Their dielectric loss is of the order of 0.001 in magnitude at room temperature. The relationships of the composition,frequencies of electric field ,testing temperature and dielectric loss, and effects of adding PET on the dielectric constant and elastic modulus are investigated. Experimental results show that the dielectric loss depends on the addition of PET,frequencies of electric field and testing temperature. The elastic modulus of composites is higher than that of the pure epoxy resin. Dielectric loss decreases with increasing frequency of the electric field. A peak phenomenon is found with the addition of PET. A sharp enhancement appears when the testing temperature is increased beyond 150 degrees centigrade.