How the structural and physicochemical properties of polyacrylamide/alginate hydrogel influence its oxygen permeability

Interpenetrating hydrogels based on sodium-alginate and crosslinked poly(acrylamide) were studied in term of their oxygen permeability. Such properties as the equilibrium water content, the free water content and the porosity are known to be preponderant for the oxygen transport through hydrated polymeric materials but are also strongly affected by the crosslinking density of the network. In the present work, these relations were studied and described. The amount of non-bound adsorbed water was determined thanks to DSC analysis. The thermoporosity method allowed the evaluation of the apparent hydrogel porosity and the electrochemical polarographic method was applied for determining the oxygen permeability level. Relations between oxygen transport properties, “free water” content and structural parameters of polymer networks were discussed.