Abstract

A new type of organoclay (Triclay) to be used in epoxy-based nanocomposites is synthesized by the addition of a multi-functional intercalating agent to primary clay (Cloisite Na+). The purpose is to enhance the interface by introducing primary bonds between the clay layers, the organic intercalating agent and the epoxy. The properties and microstructure were investigated thoroughly allowing the evaluation of the efficacy of this new epoxy-based nanocomposite. A new Liquid-Liquid method for synthesizing nanocomposites is developed. This new method improves the dispersion and exfoliation of the organoclay in the polymer matrix; thus improving the end-use properties. Archeological tests on the uncured epoxy-Triclay system demonstrate that this method results in a great increase in viscosity, even more than the most advanced high-pressure mixing method used previously. A higher viscosity of the uncured system indicates better exfoliation. In a 5wt% Triclay nanocomposite, the compressive tests on the cured samples show that there is a 45% increase in maximum stress, a 10% increase in yield stress and a 26% increase in modulus over the pure epoxy-amine system. In order to obtain the optimum nanocomposite properties, the pure epoxy-amine system, Epon828/Epi-cure 3046, is also studied. The effect of epoxy amine ratio on the solid-state micro and nano-structures is studied at the optimum curing temperature for nanocomposite production. Under these conditions it is found that the highest amount of hard phase in the cured epoxy system is not at the stoichiometric point, but rather at an epoxy-rich point.