Highly efficient polyurethane membrane based on nanocomposite of sulfonated thiacalix[4]arene-sodium alginate for...

In this study, a series of polyurethane (PU) films based on three different type of chain extenders including glycerol, sodium alginate (SA) and nanocomposite of tetrasodium thiacalix[4]arene tetrasulfonate-sodium alginate (TS-SA) were synthesized. The effect of SA and TS-SA chain extenders on different properties of the PU films were studied using FTIR, XRD, DSC, TGA, SEM, AFM, and tensile analysis and the obtained results were compared with the polyurethane film extended with glycerol. The TGA and tensile studies confirmed that incorporation of TS-SA into the polyurethane backbone provide the superior thermal and mechanical properties compared to SA. Moreover, the influence of the SA and TS-SA chain extenders on hydrophilicity of the prepared films was also investigated by contact angle measurement. The results showed that the hydrophilicity of PU/TS-SA is higher than the PU/Gly and PU/SA samples. In comparison with PU/Gly and PU/SA samples, the PU/TS-SA sample showed significant performance in water desalination via reverse osmosis technique due to its favorable porosity and improved hydrophilicity. The AFM analysis confirmed that the PU/TS-SA sample has the highest surface rouphness which cause an increase in the flux and anti-fouling property of this sample. Therefore, PU/TS-SA sample can be introduced as an efficient membrane for water desalination with enhanced thermal stability, mechanical properties, high salt rejection and water permeability.