Modification Of The Surface Properties Of Polyethylene (PE) Films Using Dielectric Barrier Discharge Plasma At Atmospheric Pressure

The surface modification of polymers is an important subject with practical values. The surface modification of materials by plasma is a cleaning and dry processing, which has huge market potential and development prospects. At present, a lot of researchers use corona or glow discharge produced by radio frequency and electron cyclotron resonance at low pressure and high frequency to modify the surface of polymers, however, corona discharge plasma is easy to damage the matrix of polymers which are treated. The plasma produced at low pressure needs expensive vacuum system, and its period is long. Air-DBD at atmospheric pressure needn't vacuum system, which surface modification of polymers saves time and reduces the cost. Therefore, it is valuable to research that air-DBD at atmospheric pressure modifies the surface properties of polymers. In this paper, PE, which is a representative polymer, is studied using DBD at atmospheric pressure in order to improve its surface energy, and the mechanism of surface modification is discussed.Firstly, in this paper, modification of the surface properties of PE films is studied using an air dielectric barrier discharge plasma at atmospheric pressure, which results arc examined by contact angle measurement, fourier transform infrared attenuated total reflection (FTIR-ATR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The law of air-DBD modifying the surface properties of PE at atmospheric pressure is summarized and the mechanism of modification is discussed. Secondly, modification of the surface properties of PE is studied using a He DBD and N₂ DBD at atmospheric pressure, respectively, which results are compared with an air-DBD. It is found that the PE surface treated by a He DBD is much uniform than that treated by a N₂ DBD and an air-DBD, which roughness is smaller than that of a N₂ DBD and an air-DBD. The water contact angle of the PE surface treated by an air-DBD can attain the smallest value than a He DBD and a N₂ DBD. Consequently, the homogeneous air-DBD used to modify the PE surface properties should be researched from now on.