USE OF INTERNAL-REFLECTION FT-IR SPECTROSCOPY FOR IN-SITU STUDY OF WATER-POLYMER-SUBSTRATE SYSTEMS

It is very difficult to analyse, by spectroscopic tools, the burried i nterphases involved in various systems such as polymer-metal, electrol yte-metal, or electrolyte-polymer-metal assemblies. The use of in-situ analysis by multiple internal reflection FT-IR (MIR) has been suggest ed to carry out such analyses, taking advantage of the low penetration depth (about 1 mu m) of the evanescent infrared waves which allows th e analysis of a solid surface in contact with strongly absorbing media (aqueous solutions or polymers). The capabilities of a home-made MIR cell are reported here and illustrated by some examples dealing with: - the in-situ determination of water diffusion coefficient through thi n poly(methyl methacrylate) films. - the study of water uptake at the interface of an adhesive-substrate system, and the effect of the surfa ce treatment of the substrate on this parameter. Such studies are carr ied out in order to assess adhesion loss and therefore the durability of the corresponding joints.