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Definición del espacio alrededor de polímeros conductores: dopaje protónico reversible de un polipirrol de cubierta
Dongwhan Lee1, Timothy M Swager
1Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, Massachusetts 02139, USA.
Journal of the American Chemical Society
|June 5, 2003
Resumen
Se sintetizó y polimerizó un nuevo derivado de pirrol para crear un polímero altamente conductor. Su conductividad se puede ajustar con precisión a través de la desprotonación y la reprotonación, por lo que es ideal para aplicaciones de detección.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química de Polímeros La Química de Polímeros es la química de los polímeros.
- Electrónica orgánica y electrónica orgánica.
Sus antecedentes:
- Minimizar el apilamiento pi-pi entre hebras es crucial para el desarrollo de polímeros conductores.
- Los derivados de pirrol son versátiles bloques de construcción para polímeros funcionales.
Objetivo del estudio:
- Para sintetizar un derivado de pirrol en forma de dosel diseñado para limitar el apilamiento pi-pi.
- Para investigar la conductividad y la estructura electrónica del polímero resultante.
- Para explorar el potencial de este polímero en la detección basada en la resistividad.
Principales métodos:
- La polimerización anódica de un derivado de pirrolo estéricamente obstaculizado.
- Técnicas espectroelectroquímicas para sondear la estructura electrónica.
- Investigando la modulación de la conductividad a través de la desprotonación/reprotonación.
Principales resultados:
- Síntesis exitosa de un derivado de pirrol en forma de dosel (2).
- La polimerización anódica dio como resultado un polímero altamente conductor (poli).
- Se observó una deslocalización de carga limitada, lo que lleva a un perfil de conductividad bien definido.
- La conductividad se moduló con precisión mediante desprotonación y reprotonación reversibles.
Conclusiones:
- El derivado de pirrolo diseñado minimiza efectivamente el apilamiento pi-pi entre cadenas.
- Poly(2) exhibe una alta conductividad y propiedades sintonizables adecuadas para la detección.
- La desprotonación/reprotonación reversible ofrece un nuevo método para el control de la conductividad en polímeros.
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