TiO_2掺杂量对PTFE/SiO_2复合材料性能的影响

采用新型化学工艺,制备了SiO2与TiO2共同填充的PTFE复合材料,系统研究了TiO2掺杂量对所制复合材料显微结构、微波介电性能和热膨胀系数的影响。结果表明,复合材料的密度、介电常数和热膨胀系数都随着掺杂量的增大而增加,吸水率随着掺杂量的增大而减小,介电损耗随着掺杂量的增大先减小后增大。当TiO2掺杂量为质量分数7%时,PTFE很好地包覆在SiO2表面,复合材料结构致密,具有与铜箔较为匹配的线膨胀系数(17.76×10–6/℃),且介电性能优良(εr=2.94,tanδ=0.000 82)。

Influences of TiO2-doping amount on the properties of PTFE/SiO2 composites

PTFE composites filled with SiO2 and TiO2 were prepared with new chemical process.The effects of TiO2 doped amounts on the microstructure and dielectric properties and thermal expansion coefficient for prepared composite dielectric material were systematically studied.The results show that composite density,permmitivity and thermal expansion coefficient were raised with increasing of TiO2 content.But water absoption is just the opposite.As the doping level increases,the dielectric loss firstly decreases and then increases.When the TiO2 doped amount is 7%(mass fraction),PTFE is well coated by the SiO2 layers and the structure of the composite is dense.The line expansion coefficient of the composite(17.76×10–6/℃) is match with the copper foil well.The dielectric properties are good(εr=2.94,tanδ = 0.000 82).