Analysis tools for fibrous nanofiller polymer composites: Macro- and nanoscale dispersion assessments correlated with mechanical and electrical composite properties

Abstract

Emerging methods to study the nanofiller agglomeration state (macrodispersion) and level of individualized nanofiller (nanodispersion) within polymer nanocomposites have been used separately to characterize microstructure and relate to material properties. However, nanofiller dispersion characteristics on different scales within polymer nanocomposites may affect the composite properties in different ways and their complement has not been studied quantitatively. In this study, the dispersion of carbon nanofiber in polycarbonate, controlled by sonication conditions, was studied by the combination of macro and nanoscale style quantitative dispersion characterization tools. The quantitative dispersion results were then correlated with the electrical and mechanical properties of the nanocomposites. Key quantitative indicators of performance were identified for nanocomposite macrodispersion such as the shape of the agglomerate size distributions and number of agglomerates per volume. However, the nanodispersion style analysis demonstrated more significant differences between similarly macrodispersed systems, providing vital information required to assess nanofiller network formation potential. The results indicate the relevant use of differently scaled image analysis processes and their necessity for a comprehensive understanding of the dispersion as well as the properties of nanocomposites. POLYM. COMPOS., 35:10–18, 2014. © 2013 Society of Plastics Engineers