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Published on: February 23, 2017
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Los iones de amonio cuaternario N-espirocíclicos para membranas de intercambio aniónico
Thanh Huong Pham1, Joel S Olsson1, Patric Jannasch1
1Polymer & Materials Chemistry, Department of Chemistry, Lund University , P.O. Box 124, SE-221 00 Lund, Sweden.
Journal of the American Chemical Society
|February 14, 2017
Resumen
Los nuevos espiroionenos ofrecen una estabilidad alcalina superior para las membranas de intercambio aniónico (AEM). Estos polímeros avanzados demuestran un excelente rendimiento en condiciones adversas, allanando el camino para aplicaciones electroquímicas duraderas.
Área de la Ciencia:
- Química de los materiales
- Ciencia de los Polímeros
- La electroquímica
Sus antecedentes:
- El desarrollo de polímeros catiónicos para membranas de intercambio aniónico (AEM) con alta estabilidad alcalina y conductividad presenta un desafío significativo en la química de los materiales.
- Los AEM existentes a menudo sufren degradación en entornos altamente alcalinos, lo que limita su rendimiento a largo plazo.
Objetivo del estudio:
- Síntesis y caracterización de nuevos ionenos de amonio cuaternario N-espirocíclicos (spiroionenos).
- Evaluar la estabilidad alcalina, las propiedades térmicas y la conductividad de estos nuevos polímeros para posibles aplicaciones de AEM.
Principales métodos:
- Síntesis de espiro-ionenos formadores de película de alto peso molecular mediante ciclo-policondensación.
- Evaluación de la estabilidad alcalina mediante espectroscopia de RMN en 1 M KOD/D2O a 80 °C durante más de 1800 horas.
- Fabricación y ensayo de membranas de intercambio aniónico (AEM) utilizando mezclas de enlaces iónicos con polibenzimidazol.
Principales resultados:
- Se han sintetizado con éxito espiro-ionenos con excelente estabilidad térmica y alcalina, que no muestran degradación después de una exposición prolongada a condiciones alcalinas adversas.
- Los espiroionenos mostraron una estabilidad razonable incluso a 120 °C.
- Los AEM basados en mezclas de espiro-ioneno alcanzaron conductividades de hidróxido de hasta 0,12 S cm−1 a 90 °C.
Conclusiones:
- Los espiroionenos representan una nueva clase de polímeros de intercambio aniónico altamente estables.
- Estos materiales demuestran un potencial significativo para el desarrollo de AEM robustos y de alto rendimiento para diversas aplicaciones electroquímicas.
- Los resultados abren nuevas vías en el diseño de materiales duraderos para entornos químicos exigentes.
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