Non-covalent functionalization of GO for improved mechanical performances of pectin composite films

The present work is aimed to develop new composite films based on pectin and functionalized graphene oxide (GOf) by using a simple casting method. The non-covalent functionalization of graphene oxide (GO) was performed by using a non-ionic surfactant (Tergitol NP9) and therefore the interaction between GO and the polymer matrix was significantly enhanced. X-ray diffraction (XRD), X-ray photoelectron spectrometry (XPS) and Fourier-transform infrared (FT-IR) were used to prove the GO functionalization. The functionalization was evidenced also by Raman spectrometry and thermogravimetric analysis (TGA). According to the mechanical tests, an improvement of the Young's modulus was recorded even at low loading of GOf within the pectin matrix which indicates a strong interaction between the polymer and GOf. By incorporation of GOf within pectin a modification of the morphology of the composite materials was observed by Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) analysis.