Possibility of Solid-State Graft Copolymerization on Poly(ethylene terephthalate) Films by Plasma Irradiation and Effects of Surface Modification

Abstract

A solid-state graft copolymerization for poly(ethylene terephthalate) (PET) films was proposed for a new surface modification technique. The functional groups included in graft monomers can be introduced on a PET surface. Allylbiguanide hydrochloric acid salt (ABG), N-methylol acrylamide (NM-AAm), and N-isopropyl acrylamide (NIP-AAm) were used as graft monomers. This technique led to a large change in the N/C atomic ratio on the PET film surfaces, which shows that nitrogen functional groups were introduced on PET surfaces. On the grafted PET films, a new N 1s spectrum appeared. This N 1s spectrum contained two components, namely, amino and amido groups, which suggests that the two groups were introduced onto the PET surfaces. In particular, isopropyl groups were introduced on the PET surface in the case of NIP-AAm. The formation of these functional groups demonstrated changes in the surface properties of PET, such as improved wettability.