Synthesis and thermal, mechanical and gas permeation properties of aromatic polyimides containing different linkage groups

Sava, Ion; Chişcă, Ştefan; Wolińska‐Grabczyk, Aleksandra; Jankowski, Andrzej; Sava, M.; Grabiec, Eugenia; Brumă, Maria

doi:10.1002/pi.4796

Cited by 23 publications

(10 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The gas permeability measurements of films of PI‐6FDA, PI‐BPADA, [PI‐6FDA] [I], and [PI‐6FDA] [Tf 2 N] were carried out by variable‐volume method and the data are summarized in Table . The sequence of gases studied is as follows: He, H 2 , N 2 , O 2 , CH 4 , and CO 2 .…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Design, synthesis, and gas permeation properties of polyimides containing pendent imidazolium groups

Shrimant

Kharul

Wadgaonkar

2018

J. Polym. Sci. Part A: Polym. Chem.

View full text Add to dashboard Cite

Film‐forming polymers containing ionic groups have attracted considerable attention as emerging materials for gas separation applications. The aim of this article was to synthesize new film‐forming polyimides containing imidazolium groups (PI‐IMs) and establish their structure–performance relationship. In this context, a new aromatic diamine, namely, N1‐(4‐aminophenyl)‐N1‐(4‐(2‐phenyl‐1H‐imidazol‐1‐yl)phenyl)benzene‐1,4‐diamine (ImTPADA), was synthesized and polycondensed with three aromatic dianhydrides, namely, 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride, 4,4‐(4,4‐isopropylidenediphenoxy) bis(phthalic anhydride), and 4,4′‐oxydiphthalic anhydride to form the corresponding polyimides containing pendent 2‐phenylimidazole groups (PI‐IEs). Next, PI‐IMs were prepared by N‐quaternization of pendent 2‐phenylimidazole groups present in PI‐6FDA using methyl iodide followed by anion exchange with bis(trifluoromethane)sulfonimide lithium salt (LiTf2N). PI‐IEs and PI‐IMs exhibited reasonably high molecular weights, amorphous nature, good solubility, and could be cast into self‐standing films from their DMAc solutions. Thermogravimetric analysis showed that 10% weight loss temperature of PI‐IEs and PI‐IMs were in the range 545–475 °C and 303–306 °C, respectively. Gas permeability analysis of films of PI‐IEs and PI‐IMs was investigated by variable‐volume method and it was observed that incorporation of ionic groups into PI‐6FDA resulted in increased permeability while maintaining selectivity. In particular, polymer bearing Tf2N− anion exhibited high CO2 permeability (33.3 Barr) and high selectivity for CO2/CH4 (41.1) and CO2/N2 (35.4). © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1721–1729

show abstract

Section: Resultsmentioning

confidence: 99%

“…The pure gas permeability measurements on films of PI‐IEs and PI‐IMs were carried out by the variable‐volume method at pressure of 6–7 bar and at room temperature (28 °C) for He, H 2 , N 2 , O 2 , CH 4 , and CO 2 . The active area of membrane was 12.4 cm 2 .…”

Section: Methodsmentioning

confidence: 99%

Design, synthesis, and gas permeation properties of polyimides containing pendent imidazolium groups

Shrimant

Kharul

Wadgaonkar

2018

J. Polym. Sci. Part A: Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…where The good solubility is due to the combination of the high number of grafted polar OH groups and aromatic rings, and the presence of hexafluoroisopropylidene units [30]. We investigated the structure of the PTA-OH by using NMR.…”

Section: Characterizationmentioning

confidence: 99%

Crosslinked polytriazole membranes for organophilic filtration

Chişcă

Falca

Musteata

et al. 2017

Journal of Membrane Science

Self Cite

View full text Add to dashboard Cite

We report the preparation of crosslinked membranes for organophilic filtration, by reacting a new polytriazole with free OH groups, using non-toxic poly (ethylene glycol) diglycidyl ether (PEGDE). The OH-functionalized polymer was obtained by converting the oxadiazole to triazole rings with high yield (98%). The maximum degree of crosslinking is achieved after 6 h of reaction. The crosslinked polytriazole membranes are stable in a wide range of organic solvents and show high creep recovery, indicating the robustness of crosslinked membranes. The influence of different casting solutions and different crosslinking time on the membrane morphology and membrane performance was investigated. The membranes performance was studied in dimethylformamide (DMF) and (tetrahydrofuran) THF. We achieved a permeance for THF of 49 L m-2 h-1 bar-1 for membranes with molecular weight cut off (MWCO) of 7 kg mol-1 and a permeance for THF of 17.5 L m-2 h-1 bar-1 for membranes with the pore dimensions of the membranes to have a MWCO, which covers ultra-and nanofiltration range.

show abstract

“…Moreover, the alkyl-CNC had the highest water contact angle value, indicating that substituted alkyl chains have a greater effect on the surface polarity of CNC than the acetyl group. The surface free energy of CNCs and the modified CNCs was determined by the Owens-Wendt approach, which divides the surface every into dispersive and polar contributions [38,39], according to the following equation:…”

Section: Contact Angle Analysis and Surface Free Energy Of Cncs And Mmentioning

confidence: 99%

Surface Alkylation of Cellulose Nanocrystals to Enhance Their Compatibility with Polylactide

2020

View full text Add to dashboard Cite

Effective surface alkylation of cellulose nanocrystals (CNCs) was developed using a nucleophilic substitution reaction with an alkyl bromide to convert hydrophilic groups on the CNCs into alkyl groups and the degree of substitution was quantitatively determined. The resultant alkylated CNCs exhibited improved dispersion in a nonpolar environment and increased hydrophobicity, compared with unmodified and acetylated CNCs. Polylactide (PLA) nanocomposites reinforced with unmodified and modified CNCs were prepared by a solution casting method and the effects of reinforcement on the thermal stability, mechanical properties, morphology, and barrier properties were investigated. In addition, modeling of the mechanical properties was evaluated to simulate the modulus of the PLA nanocomposites and results were compared with the experimental values. PLA nanocomposites reinforced with alkylated CNCs exhibited superior properties in terms of thermal stability, tensile strength, Young’s modulus, and barrier properties because of the uniform dispersion and strong interfacial adhesion between filler and matrix. This high performance and fully return-to-nature nanocomposite is expected to expand the utilization of CNCs from sustainable bioresources and the practical application of biodegradable plastics.

show abstract

Synthesis and thermal, mechanical and gas permeation properties of aromatic polyimides containing different linkage groups

Cited by 23 publications

References 58 publications

Design, synthesis, and gas permeation properties of polyimides containing pendent imidazolium groups

Design, synthesis, and gas permeation properties of polyimides containing pendent imidazolium groups

Crosslinked polytriazole membranes for organophilic filtration

Surface Alkylation of Cellulose Nanocrystals to Enhance Their Compatibility with Polylactide

Contact Info

Product

Resources

About