The addition of GO-SiO2 to synthesis polyethylene terephthalate composite with enhanced crystalline and mechanical properties

The graphene oxide-silica, GO-SiO 2 (GS) nanoparticles synthesized by in-situ hydrolysis were grafted with block polymers polyethylene glycol (PEG) and low-molecular polyethylene terephthalate (LPET) using 3-isocyanatopropyltrimethicone (IPTES) as a bridge to prepare the additive GS-IPTES plus PEG-LPET (GSIP). This grafting process was confirmed by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The GSIP of various contents was used as reinforcing fillers to prepare PET/GSIP composite by melt blending. The crystallization and mechanical properties of the PET/GSIP composite were dramatically enhanced with the addition of small amounts of GSIP. Compared with pure PET, the crystallization temperature of PET/GSIP was increased by 41 °C at 1 wt.% addition of GSIP. Moreover, the highest tensile strength was 91.2 MPa and the highest modulus was 14.7 GPa at 0.8 wt.% addition. The crystalline and mechanical properties improvements were attributed to the synergistic effects of GS and block polymer chains.