Optimization Effect of Micro Hardness by Nanoclay Clusters in Nanoclay/Epoxy Composites

Abstract

Nanoclay/epoxy composites have been investigated extensively on their mechanical and thermal properties over the last decade. Researches have been mainly focused on the control of manufacturing a fully exfoliated inter-planar structure of nanoclay platelets inside epoxy resin in order to achieve the maximum mechanical strength of the composites. Nevertheless, in reality, sole dominant structures (both exfoliated and intercalated) are hardly produced in the manufacturing process. Nanoclays would be easily agglomerated to form tiny nanoclay clusters, especially in the extrusion and injection molding processes of epoxy-based components. This paper studies the mechanical performance in terms of micro-hardness of nanoclay/epoxy composites with different nanoclay contents. The size of nanoclay clusters in the composites vary with different nanoclay contents observed by the microscopic examination. The results show that the micro-hardness of the composites could be enhanced by adding a small amount of nanoclays. However, there is an optimal limit wherein the maximum hardness of the composites is measured. Continuously increasing the amount of nanoclay could ultimately decrease the hardness of the composites.