Blended Membrane of Polyethylene‐Glycol‐Grafted‐PIM‐1 and Tröger's Base Polymer for the Separation of Pentose and Hexose

AbstractMonosaccharides are vital building blocks in bioengineering applications; however, their extraction from intricate mixtures is challenging and uses substantial amounts of energy. Polymers of intrinsic microporosity (PIMs) offer an innovative avenue for separating monosaccharides. We modified PIM‐1membranes to improve the glucose/xylose separation by incorporating polyethylene glycol monomethyl ether (mPEG). The optimal mPEG (molecular weight: 1000 Da; mass fraction: 2.5 %; solvent: methanol) delivered a xylose separation coefficient of 2.62. With the hybrid membrane of PIM‐1‐mPEG (50 w.t.%) and hydrophilic Tröger's base polymerer (DMBP‐TB, 50 w.t.%), the separation factor for xylose/glucose in an aqueous solution was 2.51 for single‐stage running and 11.32 after five‐stage running. There are large fractions of micropores for PIM‐1‐mPEG, and there is difference on solute‐membrane interactions for pentose/hexose, which are regarded to be the main driving force for the high pentose/hexose selectivity in methanol. The blending of PIM‐1‐mPEG and DMBP‐TB, integrates the microporosity and hydrophilicity, finally endues the high pentose/hexose selectivity in aqueous solution. These microporous membranes are promising materials for efficiently separating monosaccharides and jnl> small organic molecules while minimizing energy consumption. We established a solid foundation for further exploring microporous membranes for various applications, notably in bioengineering.