Water Diffusion in Glassy Polymers and their Silica Hybrids: an Analysis of State of Water Molecules and of the Effect of Tensile Stress

In-situ, time-resolved FTIR spectroscopy along with gravimetric analysis have been used to investigate water sorption and transport in several glassy polymeric matrices, characterized by different levels of interaction with water, as well as on polymer-silica hybrids. This technique has also been coupled to a dynamical-mechanical analyser to gather information on the water sorption kinetics and thermodynamics in a polymer sample submitted to stretching deformation and load. Results have been modelled by coupling the mass balance and momentum balance, using a theoretical approach developed for elastic matrices and low sorbed amounts by Larché and Cahn.