Influence of the sizes of gas molecules on their diffusion in cross-linked polyethylene

This work shows that the decrease in the diffusion coefficient during cross-linking of polymers is due to the “drift” of diffusant gas molecules into cross-links. An increase in the diameter of the gas molecule leads to a change in the “effective” structural characteristics of the cross-linked polymer (C$_{\text{npr}}$ and Z), which further enhances this effect.