Flame-Retardant Electrical Conductive.pdf

Flame-Retardant Electrical Conductive Nanopolymers Based on Bisphenol F Epoxy Resin Reinforced with Nano Polyanilines Xi Zhang,?,? Qingliang He,? Hongbo Gu,? Henry A. Colorado,§ Suying Wei,*,? and Zhanhu Guo*,? ?Integrated Composites Laboratory (ICL) Dan F. Smith Department of Chemical Engineering, Lamar University, Beaumont, Texas 77710, United States ?Department of Chemistry and Biochemistry, Lamar University, Beaumont, Texas 77710, United States §Department of Mechanical and Aerospace Engineering, University of California Los Angeles, Los Angeles, California 90095, United States *S Supporting Information ABSTRACT: Both fibril and spherical polyaniline (PANI) nanostructures have successfully served as nanofillers for obtaining epoxy resin polymer nano- composites (PNCs). The effects of nanofiller morphology and loading level on the mechanical properties, rheological behaviors, thermal stability, flame retardancy, electrical conductivity, and dielectric properties were systematically studied. The introduction of the PANI nanofillers was found to reduce the heat-release rate and to increase the char residue of epoxy resin. A reduced viscosity was observed in both types of PANI?epoxy resin liquid nanosuspension samples at lower loadings (1.0 wt % for PANI nanospheres; 1.0 and 3.0 wt % for PANI nanofibers), the viscosity was increased with further increases in the PANI loading for both morphologies. The dynamic storage and loss modulii were studied, together with the glass-transition temperature (Tg) being obtained from the peak of tan δ. The critical PANI nanofiller loading for the modulus and Tg was different, i.e., 1.0 wt % for the nanofibers and 5.0 wt % for the nanospheres. The percolation thresholds of the PANI nanostructures were identified with the dynamic mechanical property and electrical conductivity, and, because of the higher aspect ratio, nanofibers reached the percolation threshold at a lower loading (3.0 wt %) than the PANI nanospheres (5.0 wt %). The