Fabricating crumpled membranes using self‐assembled porous nanoparticles for efficient organic solvent nanofiltration

Abstract Organic solvent nanofiltration is critical in industries such as textiles and pharmaceuticals, yet the efficiency of polyamide (PA) membranes remains a challenge. Introducing nanoparticles during interfacial polymerization (IP) process can produce loose and thin PA layer. Here, a simple electrostatic self‐assembly approach is presented to synthesize porous polymer nanoparticles using tris(2‐aminoethyl)amine (TAEA) and sodium dodecyl sulfate (SDS), followed by glutaraldehyde (GA) crosslinking. These nanoparticles regulate IP process, enabling the fabrication of PA membranes with crumpled surface and reduced thickness. The membranes achieve high organic solvent permeance (e.g., 23 L m −2 h −1 bar −1 for methanol) while maintaining excellent dye rejection (e.g., 97% for orange G). They also exhibit superior performance in drug separation, including xanthophyll, vitamin B12, and protoporphyrin IX. This straightforward and versatile approach is adaptable to other diamino and polyamino molecules, providing a promising pathway for crumpled PA membrane fabrication with broad applications in high‐efficiency organic solvent nanofiltration.