Effect of surface chemistry of graphene and its content on the properties of ethylene dichloride‐ and disodium tetrasulfide‐based polysulfide polymer nanocomposites

Graphene oxide (GO) was prepared via Hummers' method and reduced by hydrazine monohydrate to obtain rGO. GO and rGO nanosheets with different contents were used in in situ interfacial polymerization of 1,2‐dichloromethane (EDC) and disodium tetrasulfide (Na₂S₄). The success of oxidation and reduction of nanosheets were confirmed by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X‐ray powder diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Proton nuclear magnetic resonance (¹H NMR) was used to determine the molecular weights of polymers. Also, dispersion of nanosheets in polymeric matrix was studied by XRD and thermal stability and thermophysical properties of nanocomposites were investigated by TGA and differential scanning calorimetry (DSC). Results showed that incorporation of nanosheets leads to lower molecular weight of matrix polymer whereas reduced nanosheets were dispersed more appropriately in matrix. According to TGA results, dispersion of nanosheets and molecular weight of the matrix are prominent factors in thermal stability of nanocomposites. Also, all samples showed glass transition temperature (T_g) less than 0°C, a cold crystallization temperature (T_cc), and subsequent melting (T_m) affected by loading content of nanosheets. POLYM. COMPOS., 38:E515–E524, 2017. © 2015 Society of Plastics Engineers