Investigation of Diffusion Processes by THz Time-Domain Reflection Spectroscopy

Liquid diffusion in polymers has been studied for the first time using terahertz (THz) time-domain reflectance spectroscopy. We show that both the position and movement of the liquid diffusion front through the polymer as a function of time can be quantified. These data are validated by comparison with the same quantities measured using magnetic resonance imaging (MRI).