Surface modifications of polyethylene terephthalate membrane by homogeneous dielectric barrier discharge plasma in He and Ne

The surfaces of the polyethylene terephthalate (PET) membrane were modified with the non-thermal plasma generated by homogeneous dielectric barrier discharge in helium and neon atmospheres, respectively. The impacts of the modification conditions, including the gas types, gas flow rate, and energy density, on the surface properties were evaluated. The surface properties of the PET membranes, before and after the modification, were characterized with attenuated total reflectance Fourier transform infrared spectroscopy, and contact angle measurement. The results show that instead of gas types, the energy density strongly affects the contact angle and the PET surface energy. As the energy density increased, the contact angle decreased and the surface energy increased to their saturated values, respectively. At a given energy density, Ne gas outpaces He gas in surface modification. We suggest that Ne gas may increase efficiency, and He gas reduce production cost.