Influences of support layer hydrophilicity on morphology and performances of polyamide thin-film composite membrane

The surface pore size and structure, as well as the hydrophilicity/hydrophobicity characterization of support layer are vital factors that affect the formation process of polyamide selective layer via interfacial polymerization. In this research, polysulfone support layers with similar pore structures but different hydrophilicity were prepared. Interfacial polymerization was conducted on the resulting support layers subsequently. As a single variable, how the support layer hydrophilicity affects morphology and performances of polyamide composite membrane were investigated. The results showed that: (1) if the surface pore sizes of support layers are similar, hydrophilic one could boost the diffusion rate of aqueous monomer into organic phase, and further affect the interfacial polymerization process; (2) hydrophilic support layer is not in favor of manufacturing polyamide composite membrane with good filtration performances and adhesion property; (3) hydrophilic support layer could not induce the poly amide formed within the support layer pore while the key factor is the interfacial position of aqueous phase and organic phase.

Automated summary

When using support layers with similar surface pore sizes, the hydrophilic support layer can promote the diffusion of aqueous monomers into the organic phase, but is not advantageous for the performance of the polyamide composite membrane.