The relationship between the heat of polymerization (deltaH) and activation energy (Ea) parameters, obtained by differential scanning calorimetry (DSC) and the ratio of epoxy resin to hardener of the thermosetting materials based on an organic-inorganic hybrid epoxy resin (OG) was investigated. Activation energy (Ea) and heat of polymerization (deltaH) increased with an increasing OG content, up to 70 wt%. Further increase in OG content to 80wt% reduced Ea and deltaH. Dynamic mechanical analysis indicates that the maximum cross-link density is obtained at 83 wt% OG, whereas fracture toughness and tensile modulus mechanical properties are maximized at 70 wt% OG.
differential scanning calorimetry; siloxane; epoxy resin; silsesquioxanes; nanocomposites
