This thesis investigates the observation and characterisation of molecular dynamics of monomers and polymers confined within the nanoporous oxide layers of anodised aerospace aluminium alloys by the use of Broadband Dielectric Spectroscopy (BDS).
Using BDS, and subsequen
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This thesis investigates the observation and characterisation of molecular dynamics of monomers and polymers confined within the nanoporous oxide layers of anodised aerospace aluminium alloys by the use of Broadband Dielectric Spectroscopy (BDS).
Using BDS, and subsequent data processing by fitting the dielectric data with Havriliak-Negami (HN) curves, Vogel-Fulcher-Tammann (VFT) curves, and Arrhenius curves, the molecular dynamics of monomers and polymers confined within different types of nanopores is investigated. Molecular dynamics is discussed using parameters such as dielectric relaxation time (τHN and τ0), transition temperature (Tv and Tx), and activation energy (Ea).
It is found from this project that when monomers are confined within the nanopores of the metal oxide layers, a fraction of them are adsorbed on to the pore wall. This adsorption leads to the formation of a new material morphology that has a relatively high restriction to molecular dynamics. The topology of the confining nanopores also plays an important role in this adsorption. When polymers are confined, the new material morphology shows relatively less restricted molecular dynamics. In this case, sample production methods and nanopore topologies have little influence on molecular dynamics.
From this thesis, it can be seen that BDS shows promising potential to be used to study the molecular dynamics of confined monomers and polymers. Overall, this project lays a groundwork for the development of BDS as a Non-Destructive Testing (NDT) tool to characterise adhesive bonds.