等离子体介质阻挡放电氟化改性环氧树脂的时效性

等离子体对材料的改性效果随放置时间会有所减弱，即表现出一定的时效性，限制了等离子体改性技术的进一步发展。为了探究等离子体介质阻挡放电（DBD）氟化改性环氧树脂的时效性，利用等离子体介质阻挡放电实现了环氧树脂表面氟化改性，并利用扫描电镜（SEM）、表面轮廓仪、X射线光电子能谱分析（XPS）、接触角测试仪、高阻计和闪络电压、表面电位测试系统对改性前和改性后放置在25 ℃老化箱中0～30 d的环氧树脂表面进行了物理形貌和化学组分的表征以及电气性能的测试。测试结果表明，DBD氟化改性实现了氟元素在环氧树脂表面接枝，这使得环氧树脂表面能降低，表面电阻率减小，陷阱能级变浅，从而加快了表面电位衰减速度，进而提升了沿面闪络电压。同时，等离子体DBD氟化改性环氧树脂表现出一定的时效性，放置30 d后，氟元素含量减少，表面能增大，表面电位衰减速度略有减慢，闪络电压也有所下降，但仍高于未处理的试样。

Plasma dielectric barrier discharge fluorination modified epoxy resin and its ageing behavior

The modification effect of plasma on the material will be weakened with the storage time, that is, it shows a certain timeliness, which limits further development of plasma modification technology. To explore ageing behavior of plasma dielectric barrier discharge (DBD) fluorinated epoxy resin, the surface fluorination of epoxy resin was realized by plasma dielectric barrier discharge. Scanning electron microscopy (SEM), surface profilometer, X-ray photoelectron spectroscopy (XPS), contact angle tester, high resistance meter, flashover voltage and surface potential testing system were used to characterize the physical morphology, chemical composition and electrical properties of epoxy resin surface before modification as well as being placed in 25 ℃ aging box for 0?30 d after modification. The experimental results show that fluoride grafting on the surface of epoxy resin is realized by DBD fluorination modification, which reduces the surface energy, surface resistivity and trap level of epoxy resin, thus speeds up the surface potential decay rate and increases the flashover voltage along the surface. After storage of 30 d, the fluorine content decreased, the surface energy increased, the attenuation rate of surface potential slowed down slightly, and the flashover voltage also decreased, but it is still higher than that of the untreated sample.