Porous synthetic smectic clay for the reinforcement of epoxy polymers

We report the properties of a porous synthetic clay (saponite, denoted SAP) for the reinforcement of rubbery and glassy epoxy polymers. Remarkably, reinforcement properties superior to those of organo-montmorillonite can be achieved without the need for a surface organic modifier, as evidenced by the improvements in tensile strength, modulus and toughness at temperature above and below the glass transition temperature of the polymer. The disordered stacking of clay platelets similar to 50 nm in lateral dimension gives rise to aggregated tactoids with a BET surface area of 920 m(2)/g, an average BJH pore size of 5.0 nm, and a pore volume of 1.98 cm(3)/g. These unique textural properties facilitate the dispersion of the tactoids into the polymer matrix and allow reinforcement of the polymer matrix in the absence of an organic modifier. (c) 2007 Elsevier Inc. All rights reserved.