Effect of Sulfonic Groups Concentration on IEC Properties in New Fluorinated Copolyamides
Artículo
Materias > Ingeniería
Universidad Europea del Atlántico > Investigación > Artículos y libros
Universidad Internacional Iberoamericana México > Investigación > Producción Científica
Abierto
Inglés
Seven aromatic polyamides and copolyamides were synthesized from two different aromatic diamines: 4,4′-(Hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline (HFDA) and 2,4-Aminobenzenesulfonic acid (DABS). The synthesis was carried out by polycondensation using isophthaloyl dichloride (1SO). The effect of an increasing molar concentration of the sulfonated groups, from DABS, in the copolymer properties was evaluated. Inherent viscosity tests were carried out to estimate molecular weights. Mechanical tests were carried out under tension, maximum strength ( σ max), Young’s modulus (E), and elongation at break (εmax) to determine their mechanical properties. Tests for water sorption and ion exchange capacity (IEC) were carried out. Proton conductivity was measured using electrochemical impedance spectroscopy (EIS). The results indicate that as the degree of sulfonation increase, the greater the proton conductivity. The results obtained showed conductivity values lower than the commercial membrane Nafion 115 of 0.0065 S cm−1. The membrane from copolyamide HFDA/DABS/1S0-70/30 with 30 mol DABS obtained the best IEC, with a value of 0.747 mmol g−1 that resulted in a conductivity of 2.7018 × 10−4 S cm−1, lower than the data reported for the commercial membrane Nafion 115. According to the results obtained, we can suggest that further developments increasing IEC will render membranes based on aromatic polyamides that are suitable for their use in PEM fuel cells.
metadata
Pali-Casanova, Ramón; Yam Cervantes, Marcial Alfredo; Zavala-Loría, José; Loría-Bastarrachea, María; Aguilar-Vega, Manuel; Dzul Lopez, Luis Alonso; Sámano Celorio, María Luisa; Crespo-Álvarez, Jorge; García Villena, Eduardo; Agudo-Toyos, Pablo y Méndez-Martínez, Francisco
mail
SIN ESPECIFICAR, SIN ESPECIFICAR, SIN ESPECIFICAR, SIN ESPECIFICAR, SIN ESPECIFICAR, luis.dzul@unini.edu.mx, marialuisa.samano@uneatlantico.es, jorge.crespo@uneatlantico.es, eduardo.garcia@uneatlantico.es, pablo.agudo@uenatlantico.es, SIN ESPECIFICAR
(2019)
Effect of Sulfonic Groups Concentration on IEC Properties in New Fluorinated Copolyamides.
Polymers, 11 (7).
p. 1169.
ISSN 2073-4360
|
Texto
polymers-11-01169-v2.pdf - Versión Publicada Available under License Creative Commons Attribution. Descargar (1MB) | Vista Previa |
Resumen
Seven aromatic polyamides and copolyamides were synthesized from two different aromatic diamines: 4,4′-(Hexafluoroisopropylidene)bis(p-phenyleneoxy)dianiline (HFDA) and 2,4-Aminobenzenesulfonic acid (DABS). The synthesis was carried out by polycondensation using isophthaloyl dichloride (1SO). The effect of an increasing molar concentration of the sulfonated groups, from DABS, in the copolymer properties was evaluated. Inherent viscosity tests were carried out to estimate molecular weights. Mechanical tests were carried out under tension, maximum strength ( σ max), Young’s modulus (E), and elongation at break (εmax) to determine their mechanical properties. Tests for water sorption and ion exchange capacity (IEC) were carried out. Proton conductivity was measured using electrochemical impedance spectroscopy (EIS). The results indicate that as the degree of sulfonation increase, the greater the proton conductivity. The results obtained showed conductivity values lower than the commercial membrane Nafion 115 of 0.0065 S cm−1. The membrane from copolyamide HFDA/DABS/1S0-70/30 with 30 mol DABS obtained the best IEC, with a value of 0.747 mmol g−1 that resulted in a conductivity of 2.7018 × 10−4 S cm−1, lower than the data reported for the commercial membrane Nafion 115. According to the results obtained, we can suggest that further developments increasing IEC will render membranes based on aromatic polyamides that are suitable for their use in PEM fuel cells.
| Tipo de Documento: | Artículo |
|---|---|
| Palabras Clave: | Polyamides; Sulfonation; Ion exchange capacity; Proton conductivity |
| Clasificación temática: | Materias > Ingeniería |
| Divisiones: | Universidad Europea del Atlántico > Investigación > Artículos y libros Universidad Internacional Iberoamericana México > Investigación > Producción Científica |
| Depositado: | 08 Mar 2022 23:55 |
| Ultima Modificación: | 01 Jun 2022 12:58 |
| URI: | https://repositorio.uneatlantico.es/id/eprint/518 |
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