CLAY-REINFORCED EPOXY NANOCOMPOSITES

New epoxy-clay nanocomposites with subambient glass transition temperatures have been prepared by the reaction of epoxide resin and a poly(ether amine) curing agent in the presence of alkylammonium ion exchanged forms of montmorillonite clays. The reinforcement provided by the 10-angstrom-thick silicate layers at 15 wt % (approximately 7.5 vol %) loading was manifested by a more than 10-fold improvement in tensile strength and modulus. The rubbery state of the polymer matrix above T(g) may facilitate stress transfer to the clay plates and allow alignment of the exfoliated silicate layers upon applying strain, thereby enhancing reinforcement.