The effects of blend ratio, compatibilization and dynamic vulcanization on permeation of gases through HDPE/EVA blends

The effects of blend ratio, compatibilization and vulcanization on the permeability of O-2 and N-2 gas through HDPE/EVA blends were analyzed. As the volume fraction of EVA in the blend increases the permeability increases. The variation in permeability is correlated with the phase morphology. Oxygen exhibits a higher permeability than nitrogen because the kinetic diameter of N-2 is greater than that of O-2. The O-2/N-2 selectivity of HDPE is higher than that of EVA and as a result the selectivity decreases with increase in EVA content in the system. The O-2 and N-2 permeabilities decrease and O-2/N-2 selectivity increase upon compatibilization and dynamic vulcanization. The experimental gas permeabilities in HDPE/EVA blends are compared with several theoretical models of permeation.