Effects of Silica/Clay Nanoparticles on Microstructural and Mechanical Properties of Epoxy Based Adhesives

Abstract

Improving the mechanical properties of the epoxy-based adhesives with nanoparticles is one of the methods which justifies the use of adhesive joints significantly. This work studies the strength of adhesively bonded single-lap joints (SLJs) considering the pure adhesive, the reinforced adhesive with nano-silica particles (NSPs), nano-clay particles (NCPs), and a combination of both nano particles. Uniaxial tensile testing of the SLJs was conducted to reveal the failure loads of the joints and their elongations at failure. Furthermore, Scanning electron microscope (SEM) images and X-ray Diffraction (XRD) Analyses were used to investigate dispersion quality. It was observed that the use of just 1 wt.% NCPs or 2 wt.% NSPs improve the failure load significantly whereas the combination of both particles generally leads to large agglomerations. It is also concluded that the dispersion quality is a key to improve the strength by shifting the failure mechanism from adhesion to cohesion type.