Preparation, morphology and thermal/ mechanical properties of Epoxy-NanoClay composites

Abstract

In this thesis, three types of clay exfoliation approaches, using different amount of surfactant, have been employed to synthesize high performance epoxy-nanoclay composites. Among the three approaches, two innovated methods are developed to prepare epoxy-clay nanocomposites with reduced/eliminated surfactants as compared to the normally used commercial organoclay, the southern clay 93A, which is widely used with 30 wt% of alkyl-ammonium ions surfactant modifier. Self-modified raw clay with 5 wt% silane surfactant and raw clay with no surface modifier are used as comparisons. TThe effects of different approaches to the morphology and thermal/mechanical properties and fracture behavior of the nanocomposites were studied. It has been found that morphologies of the composites were significantly influenced by different preparation methods, which also lead to a dramatic change in their thermal and mechanical properties of the resulting nanocomposites. The relations between the morphologies and properties were discussed and possible reinforcing mechanisms were proposed.