Effect of fabrication method on thermo-mechanical properties of an epoxy composite

Masoud Dehghan, Riadh Al-Mahaidi, Igor Sbarski, Emad Gad

Research output: Contribution to journalArticleResearchpeer-review

11 Citations (Scopus)


Epoxy resin is the key component in carbon-fibre-reinforced polymer (CFRP)-strengthening systems, since it starts to lose its properties when reaching its glass transition temperature (Tg), and subsequently, affects the whole system. The aim of this study is to enhance the properties of the epoxy to achieve a high-performance strengthening system. Epoxy composites were modified using the high-functionality resin N,N-diglycidyl-4- glycidyloxyaniline (DGOA). Thermal and mechanical tests were applied to investigate the effect of DGOA modification on the properties of the epoxy. The Tg of the DGOA-modified epoxy was increased by 9°C, which was attributed to the higher degree of cross-linking. Moreover, it showed a considerable increase in elastic modulus and decomposition temperature. Composites were also prepared using different methods such as sonication, vibration, and post-curing. Ultrasonic-mixing was proved to improve the T g of both neat and modified epoxy due to the more homogeneous network. Sonication also improved the tensile properties of the DGOA-modified epoxy dramatically. However, it had a negligible effect on the tensile strength of the neat epoxy and only increased the toughness. This was attributed to the lower network viscosity as a result of DGOA modification. Post-curing caused a substantial increase in the Tg by allowing the polymer to reach its maximum curing degree.

Original languageEnglish
Pages (from-to)368-383
Number of pages16
JournalJournal of Adhesion
Issue number5-6
Publication statusPublished - 3 Jun 2014
Externally publishedYes


  • CFRP
  • Civil Engineering
  • DGOA
  • DMA
  • Glass transition temperature
  • Modified adhesive

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