Figure 4.

Cryogelation process: monomers and/or polymers are mixed in an aqueous solvent and then the whole system is incubated at subzero temperatures for cryopolymerization and/or gelation, along with ice crystal formation; the ice crystals function then as a porogen during polymerization. After complete gelation, and when incubated at room temperature and washed with water to remove unreacted monomers or polymeric precursors, the ice crystals melt and leave behind large interconnected macropores.