عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Formation of polymer/CNT nanocomposites enhances the physical and mechanical properties of polymer matrices. Basically, the mechanical properties are investigated by means of polymer/filler interactions. The other properties such as the rheological and electrical properties are examined by particle distribution and dispersion in the polymer matrices. Due to the variety of industrial applications of polyurethane and the need to improve their properties, in the current work, the improvements of PTMEG with carbon nanotubes have been studied. The particles were acid treated in a mixture of sulfuric/nitric acid, providing uniform dispersion of the nanotubes in the polymer matrix. The rheological measurements have been used to obtain the optimum degree of MWCNT dispersion, and the formation of nanoparticles superstructure were quantified by two percolation thresholds (Ф*,Ф**) at low deformation rates. The critical percolation for PTMEG/MWCNT was estimated at 0.25-0.5 wt%. A significant improvement in the rheological characteristics was observed due to the agglomeration of particles at Ф* and continuous network of clusters at Ф**. The interfacial interaction of composites was also measured by means of relaxation time spectra and showed high improvement at Ф** (0.5 wt%). Considering the FE-SEM images of specimens, it was found that there is a nanotube network or cluster agglomeration at the concentration 0.75 wt% of MWCNT in the polymeric matrix.