Synthesis and gas transport properties of polyamide membranes containing PDMS groups

Polyimides (PIs) with single phenyl pendant substitution were prepared based on three diamines containing phenyl pendant group, namely, 2,5-bis(4-aminophenoxy) biphenyl, 2-phenyl-4,4′-diaminodiphenyl ether, and 2,5-diaminobiphenyl (p-PDA), with the dianhydride component of 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride, respectively. The physical properties of the membranes were examined, including thermal properties, fractional free volume ( FFV), solubility, and morphological structures, and were compared with the analogues without phenyl pendant. Gas transport properties of the membranes were investigated and discussed from the viewpoint of structure–property relationship. For 6FDA-derived PI membranes, gas permeability increased as the degree of PI backbone rigidity leveled up. Gas transport properties were not improved by the incorporation of phenyl pendant group for 6FDA type containing ether linkage and marginally improved as compared between PI (6FDA/p-PDA) and PI (6FDA/p-phenylenediamine (PDA)). To increase the phenyl substitution density of 6FDA/PDA-type backbone, a novel diamine bearing two phenyl pendant groups, that is, 2,6-diphenyl-1,4-diaminobenzene (p, p′-PDA) was synthesized, and PI derived from 6FDA and p, p′-PDA was prepared. The gas permeability coefficients of PI (6FDA/p, p′-PDA) were remarkably larger than those of PI (6FDA/p-PDA) and PI (6FDA/PDA).

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Effect of End Group Modification on Gas Transport Properties of 6FDA-TAPOB Hyperbranched Polyimide-Silica Hybrid Membranes

High Performance Polymers ◽

10.1177/0954008307081197 ◽

2007 ◽

Vol 19 (5-6) ◽

pp. 553-564 ◽

Cited By ~ 14

Author(s):

Tomoyuki Suzuki ◽

Yasuharu Yamada

Keyword(s):

Transport Properties ◽

Gas Transport ◽

Gas Permeability ◽

Sol Gel ◽

Silica Content ◽

Hybrid Membranes ◽

Gas Transport Properties ◽

Silica Hybrids ◽

End Group ◽

Silica Hybrid

Physical and gas transport properties of end group-modified 6FDA-TAPOB hyperbranched polyimide (HBPI)-silica hybrid membranes were investigated. Hyperbranched polyamic acids as precursors were synthesized by polycondensation of triamine, 1,3,5-tris(4-aminophenoxy)benzene (TAPOB), and dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA), and the molecular end groups were subsequently allowed to react with 3-aminopropyltrimethoxysilane (APTrMOS) and fluorine compound, 3,5-bis(trifluoromethyl)aniline (6FMA) and 1H,1H-heptadecafluorononylamine (17FN). The HBPI-silica hybrids were prepared by sol-gel reaction using the polyamic acids, water, and tetram-ethoxysilane (TMOS). The 5% weight-loss and glass transition temperatures of the hybrids considerably increased with increasing silica content, indicating effective crosslinking at polymer-silica interface mediated by APTrMOS moiety. The CO2, O2, N2, and CH4 permeability coefficients of the hybrids increased with increasing silica content. In particular, 6FMA-modified and 17FN-modified 6FDA-TAPOB HBPI-silica hybrids showed high gas permeability, arising from their high fractional free volumes. The CO2/CH4 selectivity of the hybrids increased remarkably with increasing silica content, whereas their O2/N2 selectivity remained almost constant against silica content. It was concluded that the HBPI-silica hybrids have high thermal stability, high gas permeability, and excellent CO2/CH4 selectivity, and are expected to apply to high-performance gas separation membranes.

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Self‐healing imidazolium‐based ionene‐polyamide membranes: an experimental study on physical and gas transport properties

Polymer International ◽

10.1002/pi.5802 ◽

2019 ◽

Vol 68 (6) ◽

pp. 1123-1129 ◽

Cited By ~ 11

Author(s):

Irshad Kammakakam ◽

Kathryn E O'Harra ◽

Grayson P Dennis ◽

Enrique M Jackson ◽

Jason E Bara

Keyword(s):

Experimental Study ◽

Transport Properties ◽

Gas Transport ◽

Self Healing ◽

Gas Transport Properties ◽

Polyamide Membranes

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New Poly(imide)s Bearing Alkyl Side-Chains: A Study on the Impact of Size and Shape of Lateral Groups on Thermal, Mechanical, and Gas Transport Properties

Membranes ◽

10.3390/membranes10070141 ◽

2020 ◽

Vol 10 (7) ◽

pp. 141

Author(s):

Fidel E. Rodríguez-González ◽

Germán Pérez ◽

Vladimir Niebla ◽

Ignacio Jessop ◽

Rudy Martin-Trasanco ◽

...

Keyword(s):

Transport Properties ◽

Gas Transport ◽

Gas Permeability ◽

Tensile Modulus ◽

Side Group ◽

Tert Butyl ◽

Degradation Temperature ◽

Gas Transport Properties ◽

The Impact ◽

Poly Imide

A set of five new aromatic poly(imide)s (PIs) incorporating pendant acyclic alkyl moieties were synthesized. The difference among them was the length and bulkiness of the pendant group, which comprises of linear alkyl chains from three to six carbon atoms, and a tert-butyl moiety. The effect of the side group length on the physical, thermal, mechanical, and gas transport properties was analyzed. All PIs exhibited low to moderate molecular weights (Mn ranged between 27.930–58.970 Da, and Mw ranged between 41.760–81.310 Da), good solubility in aprotic polar solvents, except for PI-t-4, which had a tert-butyl moiety and was soluble even in chloroform. This behaviour was probably due to the most significant bulkiness of the side group that increased the interchain distance, which was corroborated by the X-ray technique (PI-t-4 showed two d-spacing values: 5.1 and 14.3 Å). Pure gas permeabilities for several gases were reported (PI-3 (Barrer): He(52); H2(46); O2(5.4); N2(1.2); CH4(1.1); CO2(23); PI-t-4 (Barrer): He(139); H2(136); O2(16.7); N2(3.3); CH4(2.3); CO2(75); PI-5 (Barrer): He(44); H2(42); O2(5.9); N2(1.4); CH4(1.2); CO2(27); PI-6 (Barrer): He(45); H2(43); O2(6.7); N2(1.7); CH4(1.7); CO2(32)). Consistent higher volume in the side group was shown to yield the highest gas permeability. All poly(imide)s exhibited high thermal stability with 10% weight loss degradation temperature between 448–468 °C and glass transition temperature between 240–270 °C. The values associated to the tensile strength (45–87 MPa), elongation at break (3.2–11.98%), and tensile modulus (1.43–2.19 GPa) were those expected for aromatic poly(imide)s.

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Synthesis and gas transport properties of novel poly(ether ether ketone)s containing fluorene group

High Performance Polymers ◽

10.1177/0954008319832956 ◽

2019 ◽

Vol 31 (9-10) ◽

pp. 1173-1182 ◽

Cited By ~ 2

Author(s):

Yayun Zheng ◽

Xing Yang ◽

Meng Yuan ◽

Jujie Luo

Keyword(s):

Transport Properties ◽

Free Volume ◽

Gas Transport ◽

Gas Permeability ◽

Proton Nuclear Magnetic Resonance ◽

Resonance Spectroscopy ◽

Gas Transport Properties ◽

Ether Ether Ketone ◽

Poly Ether Ether Ketone ◽

Ether Ketone

Two novel gas separation membranes (Phenyl(Ph)-poly(ether ether ketone)s (PEEKs) and PEEKs) based on PEEKs with a high fractional free volume were designed and synthesized. The structure and thermodynamic stability of the membranes were investigated using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy, and thermogravimetric analysis. The two membranes, which were determined to be high-molecular weight polymers by gel permeation chromatography, showed good solubility in a weakly polar solvent. The gas transport properties of the Ph-PEEK membranes were investigated for different gases (CO2, O2, CH4, and N2) at 25°C and 1 atm. The Ph-PEEK-3 membrane with the largest free volume had the largest gas permeability coefficient and maintained good selectivity. The effect of operating temperature on the gas permeation of the Ph-PEEK-3 membrane was also investigated, and the maximum permeability of the four single gases was reached at 55°C and 1 atm.

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Relationship between polymer structure and gas transport properties in a series of fluorine-containing aromatic polyamide membranes for oxygen enrichment

Desalination ◽

10.1016/s0011-9164(02)00296-5 ◽

2002 ◽

Vol 144 (1-3) ◽

pp. 103-108 ◽

Cited By ~ 3

Author(s):

Chien-Chieh Hu ◽

Yi-Chien Wang ◽

Chi-Lan Li ◽

Kueir-Rarn Lee ◽

Y.C. Chen ◽

...

Keyword(s):

Transport Properties ◽

Gas Transport ◽

Aromatic Polyamide ◽

Polymer Structure ◽

Oxygen Enrichment ◽

Gas Transport Properties ◽

Polyamide Membranes

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Aromatic polyamides and copolyamides containing fluorene group

High Performance Polymers ◽

10.1177/0954008317732121 ◽

2017 ◽

Vol 30 (7) ◽

pp. 821-832 ◽

Cited By ~ 14

Author(s):

Tengyang Zhu ◽

Xing Yang ◽

Xiaoqi He ◽

Yayun Zheng ◽

Jujie Luo

Keyword(s):

Transport Properties ◽

Chemical Structure ◽

Gas Transport ◽

Gas Permeability ◽

Operating Temperature ◽

Gas Permeation ◽

Proton Nuclear Magnetic Resonance ◽

Fractional Free Volume ◽

Aromatic Polyamides ◽

Gas Transport Properties

A series of new aromatic polyamides (PAs) and copolyamides (CPAs) containing fluorene group have been synthesized through polycondensation reaction. The chemical structure was confirmed by Fourier transform infrared and proton nuclear magnetic resonance (1H NMR). PAs and CPAs exhibited the higher thermal stability ( Td15 > 378°C in nitrogen), the higher glass transition temperature ( Tg > 345°C), and excellent solubility in polar solvent. Gas transport properties of the PA and CPA membranes were investigated using different single gases (hydrogen (H2), carbon dioxide (CO2), oxygen (O2), methane (CH4), and nitrogen (N2)). We discussed the effect of chemical structure and operating temperature on gas transport properties. The results show that PA-1 containing a hexafluoroisopropylidene moiety exhibited the highest gas permeability ( PH2 = 12.71 Barrer, PCO2 = 12.26 Barrer, and PO2 = 2.62 Barrer) and reasonably good selectivity ( α(H2/N2) = 27.63, α(CO2/N2) = 26.65, and α(O2/N2) = 5.70) at 25°C and 1 atm. For all the membranes, gas permeability gradually increased with the increase in operating temperature, while the selectivity gradually decreased. These gas permeation results were well correlated with fractional free volume, interchain d-spacing ( dsp), and intermolecular interaction.

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