Molecularly Engineered 6FDA‐Based Polyimide Membranes for Sour Natural Gas Separation

Abstract

Glassy polyimide membranes are attractive for industrial applications in sour natural gas purification. Unfortunately, the lack of fundamental understanding of relationships between polyimide chemical structures and their gas transport properties in the presence of H2S constrains the design and engineering of advanced membranes for such challenging applications. Herein, 6FDA‐based polyimide membranes with engineered structures were synthesized to tune their CO2/CH4 and H2S/CH4 separation performances and plasticization properties. Under ternary mixed sour gas feeds, controlling polymer chain packing and plasticization tendency of such polyimide membranes via tuning the chemical structures were found to offer better combined H2S and CO2 removal efficiency compared to conventional polymers. Fundamental insights into structure–property relationships of 6FDA‐based polyimide membranes observed in this study offer guidance for next generation membranes for sour natural gas separation.

Sorption-enhanced mixed-gas transport in amine functionalized polymers of intrinsic microporosity (PIMs)

“…5b presents a larger collection of data / reported for microporous polymers against pure-gas CO 2 permeability, including studies that did not test sorption. For polymers reported in the literature, the / permselectivity ratio centers around 1 ± 0.2 with the lowest and highest literature values of 0.52 and 1.59 for PIM-EA(Me 2 )-TB 103 and 6FDA-DAM:DABA (1:2) 91 , respectively. Remarkably, the value of for PIM-NH 2 (290 d and 448 d) is 2.4, / surpassing all other microporous polymers considered in the literature.…”

Unparalleled Armour for Aramid Fiber with Excellent UV Resistance in Extreme Environment

“…As a high-performance organic fiber, poly(m-phenyleneisophthalamide) fiber (PMIA, known as aramid fiber 1313) is of great interest for applications in military, aerospace, transportation, electronics, etc., due to their outstanding properties including ultrahigh strength and modulus, lightweight, good fatigue resistance, insulation performance, and flame retardancy. [1][2][3][4] Although its performance has significant advantages over ordinary organic polymer fibers, it still suffers from weak heat resistance and poor ultraviolet (UV) light stability compared with many inorganic fiber materials and metal materials. [5][6][7][8][9][10] The combination of high temperature and intense ultraviolet radiation can cause a sharp decline in the mechanical properties of PMIA, which largely limits its working durability in the outdoor environment, especially in outer space under extreme ultraviolet radiation and high temperature.…”

Wearable and Robust Polyimide Hydrogel Fiber Textiles for Strain Sensors

“…Notably, no absorptions due to the amide group appear in the spectra, which can be ascertained to indicate that both polycondensation and imidization are completed in the one-step polymerization. Interestingly, a broad weak absorption between 2500 and 3500 cm –1 is observed in the PI, which could be assigned to the vibration of −COOH . However, the obvious absorptions around this wavenumber disappear in the spectrum of the PI salt.…”

“…Interestingly, a broad weak absorption between 2500 and 3500 cm −1 is observed in the PI, which could be assigned to the vibration of −COOH. 25 However, the obvious absorptions around this wavenumber disappear in the spectrum of the PI salt. Therefore, organosoluble PIs with designed carboxyl groups were synthesized via a "one-step" strategy, and the PI salt could be obtained with potassium hydroxide treatment.…”