Enhancing the electrical conductivity of a hybrid POSS–PCL/graphene nanocomposite polymer

Abstract

An electrically conductive polymer using polyhedral oligomeric silsesquioxane (POSS) nanocage incorporated into a modified poly [caprolactone based urea-urethane] (PCL)/graphene hybrid nanocomposite is described. Multilayer graphene flakes (8nm) were homogeneously dispersed into POSS–PCL at 0.1, 2, 5, and 10wt.% concentrations. This dispersion process of the graphene flakes was achieved by the use of stable dimethylacetamide (DMAc), via solution intercalation with POSS–PCL nanocomposites. The impedance spectroscopy of 5.0wt.% and higher concentration of graphene in POSS–PCL represented major improvement in conductivity over pristine POSS–PCL. The percolation threshold occurred at 5.0wt.% graphene concentration, converting the insulator POSS–PCL into a conductive POSS–PCL/graphene hybrid nanocomposite. The structures of the obtained hybrid materials were characterized with atomic force microscopy (AFM), Fourier transform infra-red (FT-IR), and Raman spectroscopy. The conductivity of the resultant nanocomposite polymer was investigated with electrochemical impedance spectroscopy (EIS). Herein, for the first time, we demonstrate a facile method of synthesizing, and describe the electrical properties of a conductive POSS–PCL/graphene nanocomposite polymer.