Triethanolamine-modulated interfacial polymerization toward microcrumpled nanofiltration membranes: Performances and mechanisms

Highly permeable thin-film composite (TFC) nanofiltration (NF) membranes featuring high separation efficiencies are of great importance for purifying surface water and ground water. Increasing the filtration area of NF membranes via accurate control of the interfacial polymerization (IP) is proposed to be an efficient way to achieve this goal. In this work, a triethanolamine (TEOA)-modulated IP was utilized to tailor the IP reaction rate and thus regulate the separation performance of NF membranes. The resultant NF membranes were characterized in terms of chemical structures, morphologies, and separation behaviors in detail. The reaction dynamic of the TEOA-doped IP was evaluated by stopped-flow spectroscopy and molecular dynamics. The results showed that the incorporation of TEOA could efficiently regulate the IP reaction rate through hydrogen bonds, increased viscosity, and acid-neutralization effects. As result, a high-performance NF membrane possessing a microcrumpled structure and excellent separation efficiency for ground water was achieved. Hence, the TEOA-modulated IP method is expected to be a maneuverable approach for tailoring excellent NF membranes for ground water treatments.