Tough Nanoparticle-Modified Polymers
File(s)
Accepted version
Author(s)
Type
Conference Paper
Abstract
A crosslinked epoxy polymer has been modified by the addition of
nano-silica particles. The particles were introduced via a sol-gel technique which gave a very well dispersed phase of nano-silica particles which were about 20 nm in diameter. The glass transition temperature was unchanged by the addition of the nanoparticles, but both the modulus and toughness were increased. The fracture energy, GIc, increased from 100 J/m2 for the unmodified epoxy to 460 J/m2 for the epoxy with 20 wt. % of nano-silica. The microscopy studies showed evidence of debonding of the nanoparticles and subsequent plastic void growth of the epoxy polymer. A theoretical model of plastic void growth was used to confirm this mechanism. The cyclic-fatigue behaviour of the epoxy polymers has also been studied and the fatigue properties were clearly enhanced by the presence of the nano-silica particles. Indeed, it was found that the values of the strainenergy release rate at threshold, Gth, from the cyclic-fatigue tests increased steadily as the toughness, GIc, also increased, i.e. as the concentration of nanosilica particles was increased.
nano-silica particles. The particles were introduced via a sol-gel technique which gave a very well dispersed phase of nano-silica particles which were about 20 nm in diameter. The glass transition temperature was unchanged by the addition of the nanoparticles, but both the modulus and toughness were increased. The fracture energy, GIc, increased from 100 J/m2 for the unmodified epoxy to 460 J/m2 for the epoxy with 20 wt. % of nano-silica. The microscopy studies showed evidence of debonding of the nanoparticles and subsequent plastic void growth of the epoxy polymer. A theoretical model of plastic void growth was used to confirm this mechanism. The cyclic-fatigue behaviour of the epoxy polymers has also been studied and the fatigue properties were clearly enhanced by the presence of the nano-silica particles. Indeed, it was found that the values of the strainenergy release rate at threshold, Gth, from the cyclic-fatigue tests increased steadily as the toughness, GIc, also increased, i.e. as the concentration of nanosilica particles was increased.
Date Issued
2010-06-01
Date Acceptance
2010-06-01
Citation
12th International Conference on Fracture 2009 (ICF-12), 2010, pp.522-531
ISBN
9781617382277
Publisher
International Congress on Fracture (ICF)
Start Page
522
End Page
531
Journal / Book Title
12th International Conference on Fracture 2009 (ICF-12)
Source
12th International Conference on Fracture (ICF 12)
Subjects
Nanoparticle
Start Date
2009-07-12
Finish Date
2009-07-17
Coverage Spatial
Ottawa, Canada