Effect of γ-Ray-Radiation-Modified Graphene Oxide on the Integrated Mechanical Properties of PET Blends

The surface modification of graphene oxide (GO) determines the interactions between GO and polymers, which possibly produces a significant impact on the mechanical properties of polymer. Here, GO was first modified with poly(glycidyl methacrylate) (PGMA) and triethylenetetramine (TTA) through γ-ray radiation. Then, a tiny small amount (0.04%) of the prepared modified GO was filled with a PET/ethylene-methyl acrylate-glycidyl methacrylate random terpolymer (PET/ST2000) blend. The morphological analyses on these filled PET blends confirmed that the surface chemical structure of GO had a crucial impact on the mechanical property of the blend. The chemical bonding between GO and ST2000 was more efficient in improving the dispersibility of GO and the compatibility between PET and ST2000, leading to a 2.5-fold increase in the impact strength, along with a slight increase in tensile strength. However, the addition of reduced GO lacking polar groups caused fatal damage in the mechanical property of the blend.