Epoxy resins are widely used materials in the industry as electrical insulators, adhesives and in aircrafts structural components because of their high mechanical stiﬀness, strength and high temperature and chemical resistance properties. But still, the inﬂuence of water uptake due to moisture adsorption is not fully understood as it detrimentally modiﬁes the electrical and chemical properties of the material. Here ,we investigate the inﬂuence of water moisture uptake on the neat epoxy material by monitoring the change in the volume resistivity and dielectric properties of epoxy material at three diﬀerent thickness conﬁgurations: 0.250 mm, 0.50 mm and 1 mm thicknesses.
Gravimetric analysis was done to monitor the mass uptake behaviour, Volume Resistivity was measured to monitor the change in conductivity of the material, and the dielectric properties were mapped to characterise the type of water mechanism available within the material during two ageing processes of sorption and desorption.
Two-stage behaviours of diﬀusion and reaction have been identiﬁed by the mass uptake analysis. Moreover, the plot of volume resistivity versus mass uptake has indicated a non-uniform relationship between the two quantities. However, the analysis of the dielectric spectrum at medium range of frequency and time has showed a change in the dipolar activities and also showed the extent to which the water molecules can be segregated between bounding to the resin or existing as free water
|Date of Award||Jul 15 2014|
|Original language||English (US)|
- Physical Sciences and Engineering
|Supervisor||Gilles Lubineau (Supervisor)|
- Anhydride Epoxy
- Water Absorption
- Volume Resistivity
- Dielectric Spectroscopy
- Relative Permittivit