Organic solvent-free in-situ polymerization of waterborne polyurethane with amino-grafted silica for carbon dioxide separation

Abstract

The novel mixed-matrix membrane (MMMs) by incorporating covalently amino groups grafted nano-silica (Amino-NP) into an eco-friendly, organic solvent-free waterborne polyurethane (OSF-WPU) matrix for the separation application of CO₂/N₂. This investigation focused on the gas permeance and separation performance of the MMMs. The optimized CO₂/N₂ separation factor reached $8.21\pm 0.47$, with a CO₂ permeance of $16.72\pm 1.02$ GPU under conditions of 1.0 bar and 25^∘C in a wet mixed-gas state. Incorporating even a tiny amount of Amino-NP efficiently enhanced CO₂ permeability and CO₂/N₂ selectivity. OSF-WPU/Amino-NP MMMs demonstrated superior performance, emphasize their potential for stable long-term operation in practical CO₂ separation applications.