The effect of dispersion condition on the structure and properties of polystyrene/graphene oxide nanocomposites

The realization of an optimum strategy for dispersing graphene nano-sheets in a thermoplastic matrix is important for obtaining a successful preparation and, consequently, a better enhancement of different properties for the resultant polymer/graphene nanocomposites. In this study, nanocomposites of polystyrene (PS) and graphene oxide (GO) were prepared using solution blending method with tetrahydrofuran as the solvent. Magnetic stirring, water bath sonication, and shear mixing were utilized to disperse GO nano-sheets in PS. Different periods of mixing for the last two techniques were examined to study their effect on the structure and properties on the PS/GO nanocomposites. For the first sample, water bath sonication and shear mixing were used for 30 and 60 minutes, respectively. For the second sample, both mixing periods were doubled. The results obtained by employing different characterization techniques showed a good dispersion of nano-sheets in the matrix and enhanced thermal and thermomechanical properties for both samples, with a superiority for the first sample in terms of storage modulus to prevent the nano-sheets from damage due to the application of sonication and mixing for a shorter period of time.