Fabrication of POSS-centered polyester network as high anti-chlorine and anti-fouling separation layer of membrane via successive Photo-ATRP and interfacial polymerization for molecular separation

Abstract

The incorporation of polyhedral oligomeric sesquisiloxane (POSS), a distinctive nanoparticle, into the membrane separation layer represents an effective strategy for enhancing the chlorine resistance of membranes. This modification contributes to both the durability of the membrane and its separation efficiency. However, POSS is easy to agglomerate, which affects the separation performance of the membrane. In this paper, POSS-centered polyhydroxy polymer (OMEPOSS-P(GMA-NMDG)) was synthesized via photo-induced atom transfer radical polymerization and used as water-soluble monomer to prepare polyester separation layer on porous substrates through interfacial polymerization with trimelanoyl chloride. The obtained POSS-centered polyester membrane exhibits a high dye removal rate exceeding 99 %, and it can realize the screening of dye molecules with different molecular weight and different charge. Notably, the membrane demonstrates excellent chlorine resistance, maintaining effective separation efficiency after exposure to sodium hypochlorite solutions at concentrations of 10 000 ppm for 96 h and 1000 ppm for 7 days. It is worth noting that the membrane showed high anti-fouling performance. This method provides a useful guideline for the development of chlorine-resistant and anti-fouling separation membranes.