Nanocomposite Cryogels Based on Poly (Vinyl Alcohol)/Unmodified Na+-Montmorillonite Suitable for Wound Dressing Application: Optimizing Nanoclay Content

A new type of nanocomposite cryogels containing polyvinyl alcohol and 0–10% of hydrophilic natural Na-montmorillonite (Na+-MMT), free from any modification, were prepared with a freeze–thaw process. The effects of nanoclay content and the sonication process on the morphology and thermomechanical properties, equilibrium water content (EWC), and the water vapor transmission rate (WVTR) of nanocomposite films were investigated at 37°C, and the amount of optimized nanocaly content was found. The kinetics of water sorption and desorption of the nanocomposites were also studied. The results showed that (Na+-MMT) may act as a co-crosslinker and improve the water vapor transmission rate and the swelling characteristics of the nanocomposite cryogels. They also showed the optimized critical concentration of nanoclay in achievement of the required sorption and desorption characteristics as well as WVTR and EWC were within the acceptable range for wound dressing and skin treatment.