Polyethersulfone-expanded graphite nanocomposites: charge transport and impedance characteristics

TitlePolyethersulfone-expanded graphite nanocomposites: charge transport and impedance characteristics
Publication TypeJournal Article
Year of Publication2010
AuthorsRamanujam, BTS, Mahale, RY, Radhakrishnan, S
JournalComposites Science and Technology
Volume70
Issue14
Pagination2111-2116
Date PublishedNOV0
ISSN0266-3538
KeywordsDifferential scanning calorimetry (DSC), Electrical properties, Modeling, Polymers, Scanning/transmission electron microscopy (STEM)
Abstract

Polyethersulfone (PES)-expanded graphite nanocomposites have been prepared by solution blending route after sonicating expanded graphite in dichloromethane. It has been observed that ultrasonication results in nanosheets formation leading to a low percolation threshold of 3 wt.%. At 5 wt.% filler loading the conductivity is of the order of 10(-2) S/cm. Hopping type of charge transport occurs at 3.2 wt.% expanded graphite in PES below which capacitive effects couple. The effective dielectric constant at low frequency increases with filler concentration. Impedance measurement has been carried out to evaluate interfacial capacitance which, for 3.2 wt.% expanded graphite addition in PES, increases to 110 pF from 32 pF for 1 wt.% expanded graphite in the polymer. DSC analysis shows an increment of 12 C in the T(g) of PES with 3 wt.% expanded graphite suggesting interaction between the polymer and filler. (C) 2010 Elsevier Ltd. All rights reserved.

DOI10.1016/j.compscitech.2010.08.008
Type of Journal (Indian or Foreign)

Foreign

Impact Factor (IF)

2.856

Divison category: 
Polymer Science & Engineering