Permeation of water through some hydrogels

The permeability to water and the average pore radius of transparent hydrogels from glyceryl methacrylate (GMA), 2-hydroxyethyl methacrylate (HEMA), propylene glycol monoacrylate (PGMA), and a polyelectrolyte complex were determined. The transport process was found to be a predominantly viscous flow in the polyelectrolyte complex and in the more dilute GMA hydrogels (74–94% water), but in HEMA hydrogel (40% water), and PGMA hydrogels (40–60% water), diffusion seemed to play a more important part in the movement of water through the gel. These hydrogels are potentially useful for surgical implants in the cornea. A comparison is made with the flow conductivity of the corneal stroma at normal hydration.