• Swingler, Steven
• Vaughan, Alun S.
• Praeger, Matthew
• Holt, Alex
• Hosier, Ian L.

Abstract

The effects of functionalizer chain length and water content were explored in a series of polyethylene/silica nanocomposites. Silane molecules with differing chain lengths (propyl, octyl and octadecyl) were used to vary the nanoparticle surface chemistry, while vacuum drying and water immersion were used to extract water from or add water to samples previously equilibrated under ambient conditions. Electrical conductivity was found to be highly dependent upon water content, while space charge distributions measured using the pulsed electro-acoustic technique revealed that both the rate of charge injection at the electrode interfaces and the charge mobility within the sample bulk were strongly dependent on absorbed water. Changes to the charge transport dynamics due to the functionalizer chain length were, however, subtle. The removal of surface hydroxyl groups appears to be the primary mechanism by which functionalization influences electrical behavior; this reduces water uptake and, as a consequence, modifies charge transport behavior.

Topics

• nanoparticle
• nanocomposite
• surface
• mobility
• functionalization
• electrical conductivity
• drying