The influence of silicate modification and compatibilizers on mechanical properties and morphology of anhydride-cured epoxy nanocomposites

Resin composition, silicate filler modification, and curing agents were var ied systematically in order to improve the performance of anhydride-cured e poxy nanocomposites based upon organoclay. The filler component was fluoroh ectorite which was rendered organophilic by means of cation exchange of int ergallery sodium cations for protonated alkylamines with chain lengths vari able from butyl (C4), hexyl (C6), octyl (C8), decyl (C10), dodecyl (C12), h exadecyl (C16), octadecyl (C18) to 12-aminododecanoic acid (C12A). The alky l chain length must exceed six C atoms to afford increased interlayer dista nces, accompanied by increased stiffness. Compatibilizer addition such as e poxidized and maleinated soy bean oil or dodecenylsuccinate afforded improv ed tensile strength without sacrificing stiffness and toughness. Morphology development, determined by means of transmission electron microscopy, and fracture behavior were examined.