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Deselectrificación por contacto de polímeros con carga electrostática.
Siowling Soh1, Sen Wai Kwok, Helena Liu
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|November 17, 2012
Resumen
La deselectrificación de contacto es un proceso recientemente descubierto en el que los polímeros de carga similar se descargan al contacto. Esta rápida transferencia de carga a las moléculas de gas atmosférico se produce debido a que se excede la fuerza de ruptura dieléctrica en el punto de contacto.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La electricidad tribal.
- Física de los polímeros Física de los polímeros
Sus antecedentes:
- La electrificación de contacto de los polímeros no se entiende completamente, con múltiples mecanismos de movimiento de carga potencialmente involucrados.
- En este estudio se investiga un nuevo mecanismo de descarga, denominado "deselectrificación de contacto".
Objetivo del estudio:
- Describir y validar el mecanismo de deselectrificación de contacto en polímeros cargados.
- Investigar la generalidad de este proceso de descarga a través de diferentes tipos de polímeros y condiciones atmosféricas.
Principales métodos:
- Cargar experimentalmente las cuentas de polímero y losas planas (poliamida 6/6, polioximetileno, politetrafluoroetileno, poliamida-imida) con polaridades similares.
- Observación de la descarga al contacto entre muestras de polímero cargadas de manera similar.
- Analizar la transferencia de carga a las moléculas de gas atmosférico ionizado utilizando una copa de Faraday.
Principales resultados:
- Tanto los polímeros cargados positivamente como negativamente (nylon, delrin, teflon, torlon) se descargan rápidamente al contacto.
- La descarga se produjo independientemente de si los polímeros en contacto eran de los mismos o diferentes materiales.
- Se detectó la transferencia de carga a las moléculas de gas atmosférico ionizado, lo que respalda el mecanismo propuesto.
Conclusiones:
- La deselectrificación de contacto es un mecanismo general para polímeros de carga similar, que implica la ionización de gases atmosféricos debido al aumento de los campos eléctricos en contacto.
- Este proceso descarga rápidamente polímeros y parece ser independiente del tipo de polímero y la composición atmosférica.
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