Study of thermal stability and thermo-mechanical behavior of functionalized soybean oil modified toughened epoxy/organo clay nanocomposite

In the current study, nano-clay was incorporated in toughened epoxy modified with epoxidized soybean oil (ESO) to improve the mechanical and thermal properties. Curing behavior was studied by Fourier Transform Infrared spectroscopy and Differential Scanning Calorimetry analysis to investigate the effect of ESO bioresin and nanoclay on cross-linking reaction. The increase in enthalpy of curing reaction and decrease in peak temperature of nanocomposite corroborated the catalytic effect of clay on the curing process. The thermal stability parameters like integral procedural decomposition temperature and decomposed activation energy were determined using Horowitz and Metzger equation. Dynamic mechanical analysis demonstrated the high storage modulus, improved crosslink density and good damping behavior of nanocomposite. Thermo mechanical analyzer was used to examine the coefficient of thermal expansion (CTE) of bio-based epoxy blend and nanocomposite in both glassy and rubbery region. The CTE value is decreased after addition of clay to the modified epoxy blend which confirmed the improved dimensional stability of the nanocomposite. TEM and X-ray diffraction analysis confirmed both intercalated and exfoliated clay platelet within the epoxy blend. (C) 2015 Elsevier B.V. All rights reserved.