The Impact of Interfacial Adhesion on the Strain- To-failure of Montmorillonite/epoxy Nanocomposites

In polymer nanocomposites, many researchers suspect that the weak interface between the host matrix and nanoparticles is responsible for the often observed reduction in the strain-to-failure relative to the pristine host matrix [1]. In 2004, a new test methodology [2] was proposed for observing the onset of clay-matrix debonding in transparent clay based nanocomposites, with the debonding process possibly indicating the onset of failure in these multiphase materials. In this initial research, the strain-to-failure of the nanocomposite with increased adhesion was lower than that of the weak interface nanocomposite. Since both nanocomposites appeared to have an intercalated morphology, these results may be associated with a change in the cure kinetics, and hence, mechanical properties, of the resin at the matrix-nanoparticle interface. To better understand these initial results, the level of matrix-nanoparticle adhesion in this research is manipulated by depositing controlled amounts of bonding and non-bonding groups on the clay surface that should promote exfoliation and adhesion without significantly altering the cure kinetics at the interface.