摘要
为了研究多层脉冲介质阻挡放电(dielectric barrier discharge,DBD)对聚四氟乙烯薄膜表面亲水性改善的影响,采用3层介质层阻挡的结构,在大气压空气中使用亚微秒级重复频率单极性脉冲电源驱动产生放电低温等离子体。在一定的处理时间条件下,通过改变薄膜所处介质层方式、施加电压幅值、电源频率及气隙间距进行聚四氟乙烯薄膜表面处理实验,并测量处理前后薄膜的表面水接触角。结果显示当3层介质层上均贴有薄膜样品时水接触角变化最大,处理效果较好;随电压幅值及频率的增加薄膜表面水接触角减小并趋于饱和,气隙间距1 mm时薄膜表面水接触角从118°变化最小可到72°左右;而对处理后薄膜进行酒精清洗,发现频率过大或过小时、气隙间距过大或过小时薄膜表面处理效果不明显,在电压40 k V、频率500 Hz、气隙间距1 mm时的薄膜表面亲水性改善效果最佳,清洗后其表面水接触角最小可达85°左右,并可进行多层薄膜同时处理。与双层介质层放电等离子体表面效果相比,该放电结构具有很好的PTFE薄膜亲水性改善效果,能够增加薄膜处理面积,为实际应用提供了可靠的数据参考及可行路线。
Atmospheric air dielectric barrier discharge is a predominate means to produce low temperature plasma, and it is significant in polytetrafluoroethylene（PTFE） surface modification application. To study the PTFE surface treatment by multi-layer pulsed DBD, the discharge low temperature plasma is produced by sub-microsecond high-voltage repetitive frequency power supply and three-dielectric-layers barrier discharge. At the 30s treatment time, the surface of PTFE films is treated by different dielectric ways, applied voltage amplitude, repetitive frequency, and gap distance. The surface water contact angles of PTFE films before and after plasma treatment are measured. The results reveal that the treatment is more effective when all samples of the dielectric layers are pasted by PTFE film. The water contact angle is at saturation when the voltage and frequency increase and is from 118 degree to about 72 degree least at lmm of the gap distance. While the treatment is ineffective after films being cleaned by alcohol clean when the frequency or gap distance is over or under a certain value. But the water contact angle of the films after clean is about 85 degree at least when the voltage is 40 kV, the frequency is 500 Hz, and the gap distance is lmm. Moreover, several layers of films can be treated simultaneously by multi-layer DBD plasma. This discharge can acquire the better treatment effect of PTFE films and provide a viable way for the industry application.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2015年第12期4048-4054,共7页
High Voltage Engineering
基金
国家自然科学基金(11305164)~~
关键词
多介质层
介质阻挡放电
亚微秒脉冲
常压空气
聚四氟乙烯
低温等离子体
表面处理
multi-dielectric-layer
dielectric barrier discharge
sub-microsecond pulse
atmospheric-pressure air
polytetrafluoroethylene
low temperature plasma
surface treatment
