A new epoxy based layered silicate nanocomposite using a hyperbranched polymer: study of the curing reaction and nanostructure development

Polymer layered silicate (PLS) nanocomposites based on epoxy resins have been widely studied previously [1], but the anticipated dramatic enhancement of their properties has not yet been realised. One approach to overcoming this problem that has recently been investigated is to incorporate hyperbranched polymers into these systems [2]. The supposed advantages of this approach are both to improve the dispersion of the clay in the epoxy resin matrix and also to increase the degree of exfoliation that takes place when the system is cured. In the present work, we further investigate this idea by fabricating PLS nanocomposites based upon a bifunctional epoxy resin and an –NH terminated poly(ethyleneimine) hyperbranched polymer, which acts as the curing agent. The effect of the clay content is studied and the results are compared also with previous work in which the curing agent was a diamine [3