Swelling processes in aqueous polymer solutions by PCS and Raman scattering

The purpose of the present work is to show how the joint employment of Raman scattering and Photon Correlation Spectroscopy (PCS), can furnish helpful information for a better comprehension of the properties of poly(ethylene oxide) in aqueous solutions. The analysis of the Raman D-LAM (Disordered Longitudinal Acoustic Mode) spectral contribution as a function of temperature reveals a slight center frequency decrease and a broadening of the D-LAM mode up to 45 degrees C. These findings, if interpreted in conjunction with PCS results, show a temperature dependence of the effective interactions between monomer units and an increase of the swollen coil size up to T = 45 degrees C. (C) 1999 Elsevier Science B.V. All rights reserved.