Morphology of epoxy/rubber blends

Abstract

The investigations on the morphological features of epoxy/rubber blends are of great importance as the morphology controls the property and performance of these blends. The characterization techniques like optical microscopy (OM), scanning electron microscopy (SEM), atomic force microscopy (AFM), and transmission electron microscopy (TEM) are commonly used to evaluate the morphology and phase distribution of the dispersed rubber particles in the epoxy matrix. These characterization techniques are used to explore the morpho- logical features in epoxy systems modified with different kinds of rubbers such as liquid rubbers, preformed core-shell rubber particles, in situ-formed rubber particles, etc. Moreover, several factors which affect the final two-phase mor-phology in the epoxy/rubber blends are also explored using these techniques. The fracture surface characteristics are also explored using morphological investiga- tion of the fracture/fatigue surface of the epoxy/rubber blends to establish the toughening mechanism operating in them. While both OM and SEM are widely used to reveal the microstructure, AFM and TEM are used to trace out the nanostructure in such blends. The current chapter gives a detailed discussion on the use of such techniques to explore the morphology and the microscopic toughening phenomena operates in epoxy/rubber blends on the basis of published reports.