Thermal and Morphological Study of Epoxy Matrix with Chemical and Physical Hybrid of Nanoclay/Carbon Nanotube

Abstract

Synergistic effects of nanoclay (NC) and carbon nanotube (CNT) as a physical and chemical hybrid on the properties of epoxy matrix were studied. The chemical hybrid of CNT-NC (CNC) was synthesized by high-temperature decomposition of methane on NC supports. The formation of CNTs on the NC surface was confirmed by transmission electron microscopy, scanning electron microscopy (SEM) and Raman spectroscopy. As-prepared CNCs were subsequently added into an epoxy matrix to make epoxy-CNC composites. The mixture of purified CNTs and NC as the physical hybrid of CNT-NC (PNC) was introduced into the epoxy matrix in order to fabricate epoxy-PNC composites. The relationship between the type of filler with the thermal and morphological performance of the epoxy-CNT-NC composite hybrids was investigated. The exfoliation characteristics of NCs and CNTs in epoxy nanocomposites were analyzed using x-ray spectroscopy (EDX) and SEM studies, respectively. Thermal behavior of the epoxy nanocomposites was studied by thermo-gravimetric-differential thermal analysis (TGA/DTG), the heat deflection temperature (HDT) test and dynamic mechanical analysis (DMA). The results indicated that the thermal characteristics of the epoxy including the degradation temperature (T deg), HDT and glass transition temperature (T g) relatively increased with the introduction of all the nanofillers, NC, CNT, PNC and CNC. The synergistic effects of CNT and NC were found to be more marked for the chemical hybrid compared to the physical one. In the case of CNC, it was observed that the CNTs attached to the clay sheets form a unique structure in which a 2D NC has several 1D CNTs attached to it. The enhanced homogeneous dispersion of NCs and CNTs in epoxy-CNC was clearly observed compared to epoxy-PNC.