Subzero temperature water absorption by crosslinked hydro-active polymeric structures

Hydrophilic polymeric network structures have exhibited an ability to absorb large quantities of water, if available, at subzero (Celsius) temperatures. While the rate of water uptake is lower when compared to that at ambient temperatures, the equilibrium water uptake is comparable. This has been attributed to temperature-dependent changes in the physicochemical parameters of the solvent (water) and the polymer, which then favours increased interactions of the solvent molecules with the hydrophilic sites within the polymeric network. The results obtained show that the temperature range of application of hydro-active polymers may be extended to subzero temperatures. In other words, it may now be possible to find applications for hydrophilic polymeric materials in processes operating at subzero temperatures and where there is need to manage and control available water. Materials studied: VP /PMMA copolymer and HEMA polymer.