Universal description of steric hindrance in flexible polymer gels

In this work, the long-time diffusion of a solute in a chemically crosslinked and flexible hydrogel is computed from a bead-spring model of a polymeric network to assess the effect of steric obstruction. The relative diffusivities obtained for a wide variety of systems can be described by an exponential decay depending on a parameter that differs from that employed for rigid gels. The mathematical expression derived here can approximately predict the diffusivity in flexible gels if steric hindrance is the mechanism ruling diffusion.

Automated summary

In this study, the long-time diffusion of a solute in a chemically crosslinked and flexible hydrogel was calculated using a bead-spring model of a polymeric network to assess the effect of steric obstruction. The relative diffusivities obtained for various systems can be described by an exponential decay, depending on a parameter different from that used for rigid gels. The mathematical expression derived in this work can approximately predict diffusivity in flexible gels if steric hindrance governs diffusion.