Atmospheric air homogenous DBD plasma excited by bipolar nanosecond pulse used for improving the hydrophilic property of polypropylene

In this paper, an air homogenous dielectric barrier discharge excited by bipolar nanosecond pulse voltage is obtained and used for the surface modification of polypropylene non-woven fabric at atmospheric pressure. Compared with the DBD plasma excited by sine alternating current (AC) voltage, nanosecond pulsed dielectric barrier discharge exhibits obvious advantages, e.g., better discharge homogeneity, lower energy cost, and lower plasma gas temperature etc. Hence it presents the potential application in improving the hydrophilic property of polypropylene non-woven fabric with high energy efficiency and without surface damage. To reduce the water contact angle of the polypropylene surface from 145° to 110°, the average energy cost of the nanosecond pulsed dielectric barrier discharge is only about 0.1 J/cm ², which is about 1/20 of AC dielectric barrier discharge. On the other hand, the surface damage of non-woven fabric induced by nanosecond pulsed dielectric barrier discharge plasma cannot be distinguished by SEM photographs.