Preparation and characterization of coaxial mullite/polypyrrole fibrous nanocomposites via self-assembling and in situ surface-initiated polymerization

After mullite fibers particles (MFPs) were surface modified, conductive polypyrrole (PPy) layer was chemically grafted on the surface of the self-assembled monolayer (SAM) coated MFPs, via in situ surface-initiated polymerization, resulting in SAM-MFPs/PPy composites. The composites possess high electrical conductivity at room temperature, weakly temperature dependence of the conductivity. The nanocomposite electrochemical properties displayed nearly symmetric charge-discharge characteristics and an ideal rectangular cyclic voltammogram. X-ray diffraction analysis confirmed that the main peaks of SAM-MFPs/PPy composites are similar to the SAM-MFPs, which reveal that the crystal structure of SAM-MFPs is well-maintained after the coating process under polymerization reaction conditions and exhibit semicrystalline behavior. Thermogravimetric analysis shows that the thermal stability of SAM-MFPs/PPy composites was enhanced and these can be attributed to the retardation effect of amine functionalized MFPs as barriers for the degradation of PPy. The morphology of SAM-MFPs/PPy composites showed the coaxial fibrous structure. POLYM. COMPOS., 35:892-899, 2014. (c) 2013 Society of Plastics Engineers