Preparation of intercalating agent-free epoxy/clay nanocomposites

A simple intercalating agent-free approach to prepare epoxy/montmorillonite (MMT) clay nanocomposite is reported. Through this new approach, no organic modifiers are needed. Thus, the cost for preparing polymer nanocomposites can be significantly reduced. The extent of dispersion and exfoliation of clay in epoxy was characterized by X-ray diffraction and transmission electron microscopy observations. It is found that the MMT clay is well-dispersed in epoxy matrix. The clay platelets in epoxy show a stacked structure with dimensions of about 1-2 mu m in length and about 20 nm in thickness. At 4.5 wt% of clay loading level, the flexural modulus of the epoxy nanocomposite is increased by about 35%. No reduction in fracture toughness or glass-transition temperature is observed. The implication of the present finding for commercialization of polymer nanocomposites is discussed.