The structure-property relationship of novolac cured epoxy resin/clay nanocomposites

Intercalated or exfoliated novolac cured epoxy resin nanocomposites were prepared with two different kinds of layered silicates – montmorillonite (PK-802) and nontronite (PK-805). The bifunctional modifiers (PI/BEN or MI/BEN) are used to modify the clays for improvement of the properties of polymer where benzalkonium chloride (BEN) acts as a compatibilizing agent and 2-phenylimidazole (PI) or 2-methylimidazole (MI) as the accelerators. Both the compatibilizer and accelerator are simultaneously intercalated into the gallery space of pure clays to form the modified clay. The novolac cured epoxy nanocomposites are prepared with these modified clays by crosslinking polymerization reaction. The properties of novolac cured epoxy/clay nanocomposites were characterized by wide-angle X-ray diffraction (WAXD), thermo-gravimetric analysis (TGA), dynamic mechanical analysis (DMA), and transmission electron microscopy (TEM) methods. According to the measurement, these novolac cured epoxy-clay nanocomposites have been shown the significant improvement in the thermal, mechanical, and barrier properties that may be applied to make printed circuit board. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers