介绍了0.1 MPa下的纳秒脉冲介质阻挡放电(DBD)对聚对苯二甲酸乙二酯(PET)材料表面进行的亲水性改善。分别采用均匀和丝状放电模式对PET表面改性处理,并采用水接触角测量、原子力显微镜观察、X射线光电子能谱分析对改性材料进行表面分析。实验发现介质阻挡放电处理后PET表面水接触角明显减小,接触角从78°下降到25°,但随处理时间的增加有饱和效应;PET表面粗糙程度增加,亲水性含氧基团被引入,从而改善了材料表面亲水性;纳秒脉冲下的均匀DBD比丝状DBD处理效果更为显著。

Surface treatment of polyethylene terephthalate(PET) films for improving the hydrophilicity using dielectric barrier discharge(DBD) excited by unipolar nanosecond pulses is presented. Homogeneous and filamentary discharges are obtained under certain experimental conditions and then used to modify the surface of PET films. The properties of PET films before and after treatment are characterized with water contact angle measurement,atomic force microscope and X-ray photoelectron spectroscope. The experimental results show that static water contact angles decrease evidently after DBD plasma treatment and the observed contact angle changes from 78° for the untreated samples to 25° after treatment. However,the decrease of contact angles is not continuous and it will reach a saturation state after certain treatment time. The improvement of surface hydrophilicity can be attributed to the enhancement of surface roughness and the introduction of oxygen-containing polar functional groups. In contrast with the filamentary DBD treatment,the homogenous DBD is more effective in PET surface treatment.