Surface characterization of polyethylene terephthalate films treated by ammonia low-temperature plasma

► In order to study the surface characterization and protein adhesion behavior of polyethylene terephthalate film, low temperature ammonia plasma was used to modify the film. ► The surface hydrophilicity of polyethylene terephthalate was significantly improved by ammonia plasma treatment and FTIR spectra showed that some new bonds such as NO and NH which could result in the improvement of the surface hydrophilicity were successfully grafted on the film surface. ► AFM and SEM experiments indicated that more protein or cells adsorbed on hydrophobic surfaces than hydrophilic ones. ► Timeliness experiments showed that the plasma treatment gave the material a certain performance only in a short period of time and the hydrophobicity recovered after 12 days.