Viscoelastic response of multilayer polymeric films of linear low-density polyethylene and ethylene vinyl alcohol copolymer

The viscoelastic response of multilayer polymeric films (sandwiches) of linear low-density polyethylene (LLDPE) and ethylene vinyl alcohol (EVOH) copolymer has been experimentally analyzed. We propose an equation to predict the mechanical response of the sandwich films from the data experimentally obtained for the monomaterial films. The equation is based on the hypothesis that the layers independently contribute to the final response and that there are no interfacial effects. The predictive character of the equation permits us to conclude that the response of the sandwich does not significantly depend on the individual layer thickness but only on the volume fraction of the EVOH in the system. More important, we find a strong sensitivity of the response to the processing conditions, which we quantitatively describe. POLYM. ENG. SCI., 55:1960–1968, 2015. © 2014 Society of Plastics Engineers