The elastoplastic response of and moisture diffusion through a vinyl ester resin–clay nanocomposite

Experimental data are reported on the elastoplastic response of and moisture diffusion through a vinyl ester resin–montmorillonite clay nanocomposite with various amounts of filler. Two simple models are developed for the elastoplastic behavior of a nanocomposite and for the anomalous diffusion of penetrant molecules. Adjustable parameters in the constitutive equations are found by fitting the observations. It is revealed that some critical concentration of filler exists (about 1 wt.-%): in the sub-critical region of concentrations, molecular mobility of the host polymer strongly decreases with the clay content, whereas in the post-critical domain, the filler fraction weakly affects mobility of chains. Key-words: Nanocomposite, Elastoplasticity, Anomalous diffusion ∗Present address: Triton Systems Inc., 200 Turnpike Road, Chelmsford, MA 01824, USA