Microstructure and mechanical properties of epoxy hybrid nanocomposites modified with acrylic tri-block-copolymer and layered-silicate nanoclay

In this study, processing, morphology and mechanical properties of acrylic tri-block-copolymer and organophilic layered-silicate nanoclay modified epoxy hybrid nanocomposites were investigated. The acrylic tri-block-copolymer preferentially self-assembled into spherical micelles in the epoxy matrix, and predominantly intercalated and few exfoliated platelets were observed with nanoclay. Three-phase ternary nanocomposites showed coexistence of both intercalated nanoclay and nanostructured block-copolymer in epoxy. Experimental results revealed that the block-copolymer significantly enhanced fracture toughness. Increased toughness of epoxy coincided with a reduction of tensile stiffness and strength. The nanoclay filled nanocomposites exhibited superior stiffness and slight improvement in tensile strength while compromising ductility. Optimum property enhancement was observed in the case of epoxy hybrid nanocomposites. Mechanical properties of the hybrid nanocomposites depend on microstructure, dispersion state and the ratio between organic and inorganic nanofiller contents. (C) 2012 Elsevier Ltd. All rights reserved.