Preparation and properties of epoxy-clay nanocomposites

Epoxy-clay nanocomposites were synthesized to examine the effects of adding different contents of nanoclays on the physical, mechanical, and thermal properties of the epoxy resin system used in composite pipes manufacturing. Diglycidyl ether of bisphenol-A (epoxy) with a cycloaliphatic amine heat curing hardner was reinforced by 1-7 wt.% of an organically modified type of montmorillonite. SEM results showed the change in failure of epoxy from brittle to tough mode by addition of nanoclays. X-ray results indicated some degree of exfoliation by 1 wt.% clay and a decrease in d-spacing in higher clay loadings after that. The heat-distortion temperature of epoxy-clay nanocomposites increased from 125.5 to 138.7 degrees C with 3 wt.% organoclay loading. Tensile and flexural modulus increased with increasing clay loading in this type of nanocomposite, but addition of organically modified clay decreased the tensile and flexural strengths and tensile elongation at break. Addition of 7 wt.% nanoclay improved the impact strength by 25.6%.