Temperature-Modulated Interfacial Synthesis of Fully Aromatic Polyurea for Superior Solvent/Thermal-Resistant Separation

Polyurea, owing to its superior solvent resistance and thermal/acid stability, has emerged as an attractive platform to replace the benchmark polyamide membranes for various applications, especially in harsh separation scenarios. Herein, we present an effective strategy to elaborate a fully aromatic polyurea membrane (FAPM) that enables superior solvent-/thermal-resistant separation performances through a temperature-modulated interfacial polymerization at an alkane-ionic liquid interface. The key of our design lies in harnessing the exceptional solvency of ionic liquid to develop aromatic polyamines instead of conventional aliphatic ones, combining a temperature-modulated synthesis to overcome the inherently sluggish kinetics of toluene diisocyanate and aromatic polyamines for boosting their reaction rate by 466 times. With this design, the defect-free and robust FAPM can be facilely synthesized in a short time and deliver a high and stable separation performance even in dimethylformamide at 80 °C. This work introduces a novel direction for exploiting robust separation materials toward harsh environments.