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均匀介质阻挡放电（DBD）等离子体可以对材料表面进行处理,且易于实现大规模连续化工业应用,因此具有广阔的应用前景。为提高其应用效果,用脉冲振荡电源激励DBD产生的常压空气中的均匀低温等离子体对聚四氟乙烯（PTFE）薄膜进行表面改性;通过接触角和表面能测量、电子扫描以及红外光谱等手段比较了等离子体处理前后的表面特性;研究了不同功率密度下材料表面特性的变化规律;考察了处理后的材料在空气中的老化效应;分析了等离子体表面改性的机理。结果表明,经DBD等离子体处理后,PTFE表面的粗糙度增大,表面引入了含氧极性基团,接触角随处理时间的增加而降低,表面能随处理时间的增加而增加,二者均在一定处理时间达到饱和值;随着等离子体功率密度的增加,表面粗糙度更大,引入的含氧极性基团更多,更少的处理时间就能得到同样的处理效果。处理后PTFE在空气中放置时老化效应主要发生在6d内,但回升后接触角值仍远低于改性前的值。“,”The surfaces of polytetrafluorethylene（PTFE） films were modified using non-thermal plasma generated by a homogeneous dielectric barrier discharge（DBD） at atmospheric pressure air driven by a μs pulse high-voltage power supply,and the surface properties of the untreated and DBD plasma treated samples were characterized by means of contact angle and surface energy measurement,scanning electron microscopy（SEM） and Fourier transformed infrared spectroscopy（FTIR）.Moreover,the changes of surface properties of the PTFE films with discharge power densities were studied,the aging effect after treatment when the treated films were exposed to open air was also investigated,and the modification mechanism was discussed.Results show that after DBD plasma treatment,the surface roughness increases remarkably,and oxygen-containing polar groups are introduced into PTFE surface.The water contact angle decreases with the increase of treatment time and surface energy increases with the increase of treatment time,and both of them reach saturated value at certain treatment time.It is found that,increasing discharge power density can treat the rougher surface and introduce more oxygen-containing polar groups into PTFE surface,so much shorter treatment time is needed to get the same treatment effect by increasing the power density.The aging effect when the treated materials are exposed to open air mainly occurs within the first 6 days,but the value of water contact angle is still far lower than that of the untreated materials even after longer storage.