Polyacrylonitrile (PAN)/TiO2 mixed matrix membrane synthesis by thermally induced self-crosslinking for thermal and organic-solvent resistant filtration

Abstract

A polyacrylonitrile (PAN)@TiO2 mixed matrix membrane is first fabricated in-situ by the nonsolvent induced phase separation (NIPS) method. Most of the in-situ generated TiO2 nanoparticles are extracted close to the upper layer of the membrane due to their high hydrophilicity, and they strongly interact with the PAN molecules; this enables the resistance of the excessive heat-induced motion of the PAN molecules and prevents structure shrinkage of the pore structures. The thoroughly self-crosslinked PAN@TiO2 membrane (TPAN@TiO2) has a strong resistance against solvents, such as N-methylpyrrolidone (NMP), dimethylacetamide (DMAc), and dimethyl sulfoxide (DMSO). All three highly polar organic solvents exhibit 24 h stable permeance at 100 °C with the new membrane. More than 99.5% of Rose Bengal and 88.5% of rhodamine B are rejected from a solution of DMAc. Considering its superior performance, the novel membrane shows promise for application in future desalination processes.