Ultrathin Amphipathic Dual‐Polymer Networks: Unlocking Hyper‐Permeable CO 2 Capture via Solvent‐Mediated Poly(Ethylene Oxide) Amorphization

Abstract

Membrane‐based carbon capture is a pivotal technology for decarbonizing the energy sector, but its practical deployment is currently constrained by the lack of scalable materials capable of delivering the hyper‐permeance required to minimize capital‐intensive membrane area. Here, we report an interface‐engineered, amphipathic dual‐polymer network that bridges this gap, achieving exceptional CO 2 permeances via a scalable “solvent‐mediated” coating process. By integrating hydrophilic poly(ethylene oxide)‐based (PEO) block copolymers within a highly crosslinked hydrophobic polydimethylsiloxane (PDMS) network, we formed an amphipathic dual‐polymer network structure with completely amorphized PEO segments, unlocking intrinsic transport properties more than an order of magnitude higher than the control. Additionally, we introduce a “pseudo‐three‐layer” interfacial architecture in thin‐film composite (TFC) membranes generated by solid‐state surface mixing, which enables defect‐free coatings of sub‐100‐nm selective layers on hydrophobic supports without the need for surface treatment. The resulting TFC membranes deliver CO 2 permeances up to 2402 GPU (hollow fiber) and 6887 GPU (flat sheet) with selectivities > 20, redefining the performance limit for Pebax‐based materials. We further demonstrate the industrial relevance of this versatile platform by fabricating a 1‐inch hollow fiber module with stable long‐term performance, establishing a direct, generalizable pathway from material physics to functional, scalable carbon capture membrane devices.