Environmentally responsible synthesis of polymer-nano fused composite membranes with long-term stability for sustainable CO2 separation

First report of TamiSolve® NxG as green solvent for accelerated synthesis of PIM-1. • PIM-1 backbone architected via in situ fusion process with water-synthesized MOFs. • Polymer-nano fused membrane delivered enhanced CO 2 separation and aging resistance. • Economic study confirmed financial gains of TamiSolve® NxG in polymer synthesis. Membrane-based CO 2 separation offers lower-energy alternative to conventional amine scrubbing but remains constrained by permeability-selectivity trade-off, physical aging, and the environmental impact of deleterious fabrication solvents. The lack of sustainable polymer synthesis strategies and limited evaluation of economic feasibility hinder large-scale deployment of next-generation membranes. Here, we report an environmentally responsible synthesis of polymers of intrinsic microporosity (PIM-1) using the greener solvent TamiSolve® NxG under accelerated synthesis conditions (2 h, 80 °C), replacing conventional hazardous solvents. To enhance structural stability and mitigate physical aging, a polymer-nano fused (PNF) architecture was developed through direct in situ anchoring of aqueous-synthesized Zr-based metal-organic frameworks (MOFs) into the polymer backbone via one-step condensation polymerization. Spectroscopic analysis confirms the formation of covalent diarylamine-like linkages, enabling controlled branching and restricted chain mobility. Positron annihilation lifetime spectroscopy (PALS) and molecular dynamics simulations reveal finely tuned fractional free volume and enhanced nanoscale uniformity. The PNF membranes demonstrate enhanced CO 2 separation performance with sustained stability over 365 days, addressing a key barrier to industrial implementation. Preliminary economic assessment shows TamiSolve® NxG is a cost-competitive and lower-toxicity solvents, supporting safer membrane manufacturing. We envisage this work establishing a one-pot architecture as a viable pathway to sustainable, high-performance CO 2 separation membranes. Download: Download high-res image (395KB) Download: Download full-size image