Low electric field induction in BaTiO3-epoxy nanocomposites

Epoxy is widely used material, but epoxy has limitations in terms of brittleness in failure, and thus researchers
explore toughening and strengthening options such as adding a second phase or using electromagnetic fields
to tailor toughness and strength, on demand and nearly instantaneously. Such approach falls into the category
of active toughening but has not been extensively investigated. In this research, Si-BaTiO3 nanoparticles were
used to modify the electro-mechanical properties of a high-performance aerospace-grade epoxy so as to study
its response to electric fields, specifically low field strengths. To promote uniform dispersion and distribution, the Si-BaTiO3 nanoparticles were functionalised with silane coupling agents and mixed in the epoxy Araldite LY1564
at different content loads (1, 5, 10 wt%), which was then associated with its curing agent Aradur 3487. Real-time
measurements were conducted using Raman spectroscopy while applying electric fields to the nanocomposite
specimens. The Raman data showed a consistent trend of increasing intensity and peak broadening under
the increasing electric field strength and Si-BaTiO3 contents. This was attributed to the BaTiO3 particles’ dipolar displacement in the high-content nanocomposites (i.e., 5 wt% and 10 wt%). The study offers valuable insights on how electric field stimulation can actively enhance the mechanical properties in epoxy composites, specifically in
relatively low fields and thin, high-aspect-ratio composite layers which would require in-situ mechanical testing
equipped with electric field application, an ongoing investigation of the current research.