Gas transport in fluorothiophenyl modified PVC membranes

A Noble‐Metal‐Free Porous Coordination Framework with Exceptional Sensing Efficiency for Oxygen

“…Nevertheless, the O 2 adsorption amount reaches 5.9 cm 3 (STP) g −1 at 1 bar, being equivalent to a solubility of 0.21 mol L −1 , which is much higher than the highest values of solvents and solid porous matrixes used for oxygen‐sensing (8×10 −3 mol L −1 for ethyl cellulose) 22. The adsorption/desorption can reach equilibrium within 1 s, giving a large diffusion coefficient 1.8×10 −5 cm 2 s −1 (Figure 4 d and Figure S10), which is similar to those of highly porous PCPs, such as IRMOF‐123 and significantly higher than those of oxygen‐permeating polymers, such as aromatic derivative‐labeled polystyrene films (2.8–5.3×10 −7 cm 2 s −1 )24 and fluorothiophenyl modified polyvinyl chloride membranes (1.8–4.1×10 −8 cm 2 s −1 ),25 and comparable with those of mesoporous nanocomposites of silicone resin/inorganic filler (0.05–3.6×10 −5 cm 2 s −1 ) 5. 26 Based on the solubility and diffusion coefficient values of 1 , its oxygen permeability can be calculated as 3.8×10 −9 mol cm −1 s −1 bar −1 , which is 2–4 orders of magnitude higher than for other solid porous matrixes (10 −13 –10 −11 mol cm −1 s −1 bar −1 ),5, 26 which accounts for its unexpectedly high oxygen‐sensing efficiency considering the relatively short fluorescence lifetime compared with phosphorescent dyes.…”

Surface Modification of PVC Membranes Using Fluorothiophenol Compounds

“…At this moment, experiments are underway to further evaluate the diffusion properties of these selectively surface modified PVC films in comparison to homogeneously modified PVC. [36] …”

“…[34][35] It is has been shown very recently that functionalized PVC membranes, in bulk, with relatively bulky chemical moieties containing fluorine atoms in their structure display very different diffusion properties than pristine PVC. [36] Therefore taking advantage of our experience in the selective surface chemical modification of PVC the purpose of this work is twofold, on the one hand, to prepare diverse samples of surface functionalized polymer films by reacting in a controlled way PVC chains with 4-fluoro-, 3,4-difluoroand pentafluorothiophenol in solvent/non-solvent mixtures as a reaction medium. On the other hand, the second objective is to understand under which conditions a modification reaction evolves with time towards a homogeneously modified film or towards a film selectively modified at the surface.…”

Preparation and performance evaluation of composite hollow fiber membrane for SO2 separation

“…Poly (vinyl chloride) (PVC) is one of the most widely used vinyl polymers in the world because of its low cost, easy process ability, and recyclability. However, PVC membranes exhibit low permeability for gas separation due to their high chain compactness and the low segmental motion of the polymeric chain . PVC synthesized with POEM presents high affinity for polar gases such as SO 2 .…”