摘要
Ceramic and polytetrafluoroethylene composites as dielectric materials have a low dielectric loss at high frequency and play an important role in the modern communication field.However,room temperature phase transformation of PTFE resins,which is accompanied by a large volume change(>400 ppm/℃),seriously affects the dimensional stability and performance stability of materials.The LD125 modified glass fiber(GF)was introduced to the CaO-Li2 O-Sm2O3-TiO2(CLST)/PTFE composite,to reduce the thermal expansion coefficient(CTE)of the composites.The tri-phase composites(CLST/PTFE/GF)show the low dielectric loss and excellent machine-ability.The effect of GF content on the dielectric properties and CTE was also investigated.The CLST/PTFE filled with 5%GF exhibits the best overall performance,which is a promising microwave dielectric material for microwave communication.
Ceramic and polytetrafluoroethylene composites as dielectric materials have a low dielectric loss at high frequency and play an important role in the modern communication field. However, room temperature phase transformation of PTFE resins, which is accompanied by a large volume change（> 400 ppm/℃）,seriously affects the dimensional stability and performance stability of materials. The LD125 modified glass fiber（GF） was introduced to the CaO-Li2 O-Sm2O3-TiO2（CLST）/PTFE composite, to reduce the thermal expansion coefficient（CTE） of the composites. The tri-phase composites（CLST/PTFE/GF） show the low dielectric loss and excellent machine-ability. The effect of GF content on the dielectric properties and CTE was also investigated. The CLST/PTFE filled with 5% GF exhibits the best overall performance,which is a promising microwave dielectric material for microwave communication.
基金
supported by the National Natural Science Foundation of China(No.51572205)
the Equipment Pre-Research Joint Fund of EDD and MOE(No.6141A02033209)
the Fundamental Research Funds for the Central Universities(WUT:Nos.2017III035,2018III019)
the Natural Science Foundation of Hubei Province,China(No.2014CFB854)
