Structural details, viscoelastic and mechanical response in blends of a vinyl alcohol-ethylene copolymer and a metallocenic ethylene-1-octene copolymer

Some structural details and the viscoelastic and mechanical response of blends of a vinyl alcohol-ethylene (VAE), and a metallocenic ethylene-1-octene copolymer (CEO), have been analyzed. Both copolymers exhibit crystalline lattices whose diffraction peaks and long spacings appear at very similar spacing intervals. More information about the crystalline region is obtained from differential scanning calorimetry (DSC) measurements due to the difference in melting temperatures found for each of them. In addition, DSC results point out an inhibition of the VAE crystallization with CEO presence that is cooling-rate dependent. A decrease of rigidity and yield stress is observed as CEO content increases in the blends. However, the changes found in the mechanical parameters are not as significant as the variation in oxygen permeability. This feature seems to be due to the disruption of intra and intermolecular hydrogen interactions.