Preparation, morphology, and properties of conducting polyaniline‐grafted multiwalled carbon nanotubes/epoxy composites

Abstract

Abstract Polyaniline‐grafted multiwalled carbon nanotubes (PANI‐ g ‐MWNTs)/epoxy composites were prepared by solution blending and mould casting. Transmission electron microscope, scanning electron microscope, differential scanning calorimetry, thermogravimetric analysis, electrical conductivity measurement, and tensile and flexural measurements were used to characterize the morphology, thermal, electrical, and mechanical properties of the composites. The results showed that MWNTs were encapsulated by conducting dodecyl benzene sulfonic acid‐doped PANI forming a core (MWNTs)–shell (PANI) nanostructure. PANI coatings swelled in tetrahydrofuran and MWNTs were homogenously dispersed in epoxy matrix. With PANI‐ g ‐MWNTs introducing into epoxy resin, curing reaction was promoted and thermal stability of the composites was enhanced. Because of conducting PANI chains wrapping on the surface of MWNTs and well dispersion of MWNTs in epoxy matrix, electrical conductivity at room temperature of the composites was increased by seven orders of magnitude compared with neat epoxy. In the PANI‐ g ‐MWNTs/epoxy composites, terminal amino groups of PANI coatings reacted with epoxy matrix during curing reactions, which guaranteed interfacial adhesion between MWNTs and epoxy resin. Mechanical properties including tensile strength, Young's modulus, flexural strength, and flexural modulus of the composites were increased by 61%, 43%, 78%, and 49% compared with neat epoxy, respectively. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012