Surface Treatment of Polypropylene Films Using Dielectric Barrier Discharge with Magnetic Field

Atmospheric pressure non-thermal plasma is of interest for industrial applications.In this study,polypropylene (PP) films are modified by a dielectric barrier discharge (DBD) with a non-uniform magnetic field in air at atmospheric pressure.The surface properties of the PP films before and after a DBD treatment are studied by using contact angle measurement,atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS).The effect of treatment time on the surface modification with and without a magnetic field is investigated.It is found that the hydrophilic improvement depends on the treatment time and magnetic field.It is also found that surface roughness and oxygen-containing groups are introduced onto the PP film surface after the DBD treatment.Surface roughness and oxygen-containing polar functional groups of the PP films increase with the magnetic induction density.The functional groups are identified as C-O,C=O and O-C=O by using XPS analysis.It is concluded that the hydrophilic improvement of PP films treated with a magnetic field is due to a greater surface roughness and more oxygen-containing groups.