Multifunctional Properties of Epoxy Nanocomposites Reinforced by Aligned Nanoscale Carbon
File(s)
Author(s)
Type
Journal Article
Abstract
The present paper compares improvements to the fracture energy and electrical conductivity of epoxy nanocomposite materials reinforced by one-dimensional carbon nanofibres (CNFs) or two-dimensional graphene nanoplatelets (GNPs). The effects of the shape, orientation and concentration (i.e. 0.5, 1.0, 1.5 and 2.0 wt%) of nanoscale carbon reinforcements on the property improvements are presented. Alignment of the nano-reinforcements in the epoxy nanocomposites is achieved through the application of an alternating current (AC) electric-field before gelation and curing of the epoxy resin. Alignment of the nano-reinforcements increased the electrical conductivity and simultaneously lowered the percolation threshold necessary to form a conductive network in the nanocomposites. Nano-reinforcement alignment also increased greatly the fracture energy of the epoxy due to a higher fraction of the nano-reinforcement participating in multiple intrinsic (e.g. interfacial debonding and void growth) and extrinsic (e.g. pull-out and bridging) toughening mechanisms. A mechanistic model is presented to quantify the contributions from the different toughening mechanisms induced by CNF and GNP nano-reinforcements on the large improvements in fracture toughness. The model results show that one-dimensional CNFs are more effective than GNPs at increasing the intrinsic toughness of epoxy via void growth, whereas two-dimensional GNPs are more effective than CNFs at improving the extrinsic toughness via crack bridging and pull-out.
Date Issued
2016-01-13
Date Acceptance
2016-01-13
Citation
Materials and Design, 2016, 94, pp.554-564
ISSN
0261-3069
Publisher
Elsevier
Start Page
554
End Page
564
Journal / Book Title
Materials and Design
Volume
94
Copyright Statement
© 2016, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
Subjects
Nanocomposite
Electrical conductivity
Fracture toughness
Modelling
Publication Status
Published