Hybrid membranes based on short side chain perfluorinated sulfonic acid membranes (Inion) and heteropoly acid salts

2018 ◽  
Vol 28 (6) ◽  
pp. 657-658 ◽  
Author(s):  
Ivan A. Prikhno ◽  
Kseniya A. Ivanova ◽  
Grigorii M. Don ◽  
Andrei B. Yaroslavtsev
Keyword(s):  
Sulfonic Acid ◽  
Heteropoly Acid ◽  
Side Chain ◽  
Hybrid Membranes ◽  
Short Side ◽  
Perfluorinated Sulfonic Acid ◽  
Acid Salts

Spectroscopic Studies of Heteropoly Acid-doped 3M Perfluorinated Sulfonic Acid Polymer Membranes

2019 ◽  
Vol 1 (6) ◽  
pp. 255-262 ◽  
Author(s):  
Andrew M. Herring ◽  
Fanqin Meng ◽  
Matthew Frey ◽  
Steve Hamrock ◽  
John Turner ◽  
...  
Keyword(s):  
Sulfonic Acid ◽  
Heteropoly Acid ◽  
Polymer Membranes ◽  
Spectroscopic Studies ◽  
Perfluorinated Sulfonic Acid

Dynamic Emergence of Nanostructure and Transport Properties in Perfluorinated Sulfonic Acid Ionomers

2020 ◽  
Author(s):  
Adlai Katzenberg ◽  
Debdyuti Mukherjee ◽  
Peter J. Dudenas ◽  
Yoshiyuki Okamoto ◽  
Ahmet Kusoglu ◽  
...  
Keyword(s):  
Rate Constant ◽  
Sulfonic Acid ◽  
Mass Fraction ◽  
Gas Permeability ◽  
Transport Processes ◽  
Segmental Mobility ◽  
The Matrix ◽  
Swelling Rate ◽  
Ion Conducting ◽  
Perfluorinated Sulfonic Acid

<p>Limitations in fuel cell electrode performance have motivated the development of ion-conducting binders (ionomers) with high gas permeability. Such ionomers have been achieved by copolymerization of perfluorinated sulfonic acid (PFSA) monomers with bulky and asymmetric monomers, leading to a glassy ionomer matrix with chemical and mechanical properties that differ substantially from common PFSA ionomers (e.g., Nafion™). In this study, we use perfluorodioxolane-based ionomers to provide fundamental insights into the role of the matrix chemical structure on the dynamics of structural and transport processes in ion-conducting polymers. Through <i>in-situ</i> water uptake measurements, we demonstrate that ionomer water sorption kinetics depend strongly on the properties and mass fraction of the matrix. As the PFSA mass fraction was increased from 0.26 to 0.57, the Fickian swelling rate constant decreased from 0.8 s<sup>-1</sup> to 0.2 s<sup>-1</sup>, while the relaxation rate constant increased from 3.1×10<sup>-3</sup> s<sup>-1</sup> to 4.0×10<sup>-3</sup>. The true swelling rate, in nm s<sup>-1</sup>, was determined by the chemical nature of the matrix; all dioxolane-containing materials exhibited swelling rates ~1.5 - 2 nm s<sup>-1</sup> compared to ~3 nm s<sup>-1</sup> for Nafion. Likewise, Nafion underwent relaxation at twice the rate of the fastest-relaxing dioxolane ionomer. Reduced swelling and relaxation kinetics are due to limited matrix segmental mobility of the dioxolane-containing ionomers. We demonstrate that changes in conductivity are strongly tied to the polymer relaxation, revealing the decoupled roles of initial swelling and relaxation on hydration, nanostructure, and ion transport in perfluorinated ionomers. </p>

scholarly journals Synthesis and Biological Activity of Brassinosteroid Analogues with a Nitrogen-Containing Side Chain

2020 ◽  
Vol 22 (1) ◽  
pp. 155
Author(s):  
Mikhail V. Diachkov ◽  
Karoll Ferrer ◽  
Jana Oklestkova ◽  
Lucie Rarova ◽  
Vaclav Bazgier ◽  
...  
Keyword(s):  
Biological Activity ◽  
Functional Groups ◽  
Side Chain ◽  
Biotic And Abiotic Stresses ◽  
Short Side ◽  
Arabidopsis Root ◽  
Physiological Processes ◽  
Growth Promoting ◽  
The Impact ◽  
Brassinosteroid Analogues

Brassinosteroids are a class of plant hormones that regulate a broad range of physiological processes such as plant growth, development and immunity, including the suppression of biotic and abiotic stresses. In this paper, we report the synthesis of new brassinosteroid analogues with a nitrogen-containing side chain and their biological activity on Arabidopis thaliana. Based on molecular docking experiments, two groups of brassinosteroid analogues were prepared with short and long side chains in order to study the impact of side chain length on plants. The derivatives with a short side chain were prepared with amide, amine and ammonium functional groups. The derivatives with a long side chain were synthesized using amide and ammonium functional groups. A total of 25 new brassinosteroid analogues were prepared. All 25 compounds were tested in an Arabidopsis root sensitivity bioassay and cytotoxicity screening. The synthesized substances showed no significant inhibitory activity compared to natural 24-epibrassinolide. In contrast, in low concentration, several compounds (8a, 8b, 8e, 16e, 22a and 22e) showed interesting growth-promoting activity. The cytotoxicity assay showed no toxicity of the prepared compounds on cancer and normal cell lines.

scholarly journals Composite short-side-chain PFSA electrolyte membranes containing selectively modified halloysite nanotubes (HNTs)

2021 ◽  
Author(s):  
Sahng Hyuck Woo ◽  
Aurélie Taguet ◽  
Belkacem Otazaghine ◽  
Alia Akrout ◽  
Sara Cavaliere ◽  
...  
Keyword(s):  
Halloysite Nanotubes ◽  
Side Chain ◽  
Short Side ◽  
Electrolyte Membranes
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