Brillouin spectroscopy investigations of poly(ethylene glycol) water and organic solvent mixtures

Brillouin spectroscopy has been applied to study a synthetic polymer and its solutions in polar and nonpolar solvents. Of particular interest has been the effect of concentration, temperature and polarity of the solvent on the mechanical properties of the mixtures studied. The experimental methods applied permitted investigation of the structural relaxation process related to the dynamics of changes in the internal structure of the polymer chains. It has been shown that the quantitative analysis of the relaxation process can be made in terms of the model based on the theory of viscoelasticity of liquids. The association processes in the systems studied have been analysed assuming the Natta-Baccaredda model. The model has been shown to be successfully applicable for description of mixtures of the polymers interacting with solvents. The limitations of the model in the situation when one of the components of the solution is neutral, while the other one undergoes strong self-association, has been considered.© (2006) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.