合成了一种端环氧基的联苯型液晶(LCEP),采用红外光谱(FT-IR)、示差扫描量热法(DSC)和偏光显微镜(POM)对其结构和热性能进行了分析,并以LCEP、环氧树脂、无机粉体(Al2O3和AlN)制备了环氧塑封料,通过对其力学性能、导热系数、线膨胀系数、电性能及热稳定性的测试研究了LCEP及无机粉体的加入对塑封料性能的影响。结果表明:加入LCEP后,塑封材料的冲击性能、弯曲性能均有所提高。同时,塑封料的导热系数、介电常数、热分解温度随着Al2O3、AlN含量的增加而增大,LCEP对于提高材料的导热性和热稳定性也有一定贡献。而线膨胀系数、介电损耗随着Al2O3和AlN含量的增加而降低,加入LCEP后塑封料的线膨胀系数略有降低。
A epoxy terminated biphenyl-type liquid crystal(LCEP) was synthesized.Its structure and thermal properties were analyzed by using infrared spectroscopy(FT-IR),differential scanning calorimetry(DSC) and polarized light microscopy(POM).The epoxy molding compound was prepared by LCEP,epoxy resin and the inorganic powder(Al2O3 and AlN).The effect of the addition of LCEP and inorganic powder on the performance of the molding compound was studied by the testings of mechanical property,thermal conductivity,coefficient of linear expansion,electrical property and thermal stability.The results showed that: the impact properties and flexural properties were improved by the addition of LCEP.At the same time,the thermal conductivity,dielectric constant and thermal decomposition temperature of molding compound were increased with the increasing of Al2O3 and AlN content.The LCEP played a certain role in improving the thermal conductivity and thermal stability of the material.The linear expansion coefficient and dielectric loss were decreased with the increasing of Al2O3 and AlN content.The coefficient of linear expansion of the molding compound was slightly decreased by adding LCEP.