Among the industrial methods used for capturing CO 2 (absorption, distillation, etc.), [1] membrane technology, [2][3][4][5][6][7][8][9][10][11] which offers advantages such energy saving, simple design and scale-up, is becoming continually more prevalent. High permeability combined with reasonable selectivity is the most important goal in developing membranes for gas separation. This goal is usually achieved through the use of polymeric membranes, through which gas transport is controlled by gas-diffusivity in glassy polymers and by gas-solubility in rubbery polymers. De novo design of synthetic membrane materials like blockco-polymers, [2][3][4][5] polymeric composites, [6,7] mixed-matrix hybrids [8] and pseudo-microporous polymers [9][10] metal organic frameworks-MOFs [1,11] has been identified as an emerging area of interest. The combination or replacement of classical glassy polymers with crystalline MOFs, ZIFs, or zeolites provides molecularly controlled permeability and selectivity. However, attempts to obtain mechanically stable and homogeneous layers on various supports have been met with difficulty.Taking advantage of the high permeabilities and flexible casting properties observed for rubbery polymers, we decided to build ROFs as new membrane separation systems for gases. ROFs may provide premises for more fine structural interaction of diffusing gas molecules with molecular addressable domains. Minimizing the size of ultradense addressable transporting domains [12][13][14][15] would make it possible to improve the limits of interaction of gas molecules with percolated conductive domains with high diffusional behaviors. [16][17][18][19] Such an improvement is specifically of interest to membrane scientists (Figure 1).Furthermore, the size of addressable elementary domains for the diffusion of gas molecules is reminiscent of the situation where pixel size determines the quality of resulting images in LCD devices. Within this context, we previously showed that dynamic covalent polymers, [15] or dynamers, [20][21][22][23] generated from reversibly interacting monomers, offer the possibility to address these issues. [24,25] In dynamers, the components are reversibly connected, and they self-assemble in such a fashion that their overall morphology overrides defects during the forAbstract: Obtaining high permeability whilst keeping a reasonable selectivity is the most important challenge in the development of membrane systems for gas separation. Satisfactory performance is usually obtained with polymeric membranes through which gas transport is controlled by gas-diffusivity in glassy polymers and by gas-solubility in rubbery polymers. During the last decade, important advances in this field have been made possible by molecular control of gas separation properties. The combination or replacement of classical glassy polymers with metal-organic crystalline frameworks (crystalline MOFs), such as zeolitic imidazolate frameworks (ZIFs) or other zeolites, provides reasonable permeability through the porous networks...

The adequate selection of macromonomers, dialdehyde core connectors and of coordinating metal ions makes possible the generation of metallodynameric materials, allowing the fine modulation of the gas transport through rubbery membranes.

The adequate selection of components makes possible the generation of double dynameric membranes, allowing the fine constitutional modulation of the gas transport performances.