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Polyethyleneoxide‐Dynamics in Aqueous Solutions Studied by Nuclear Magnetic Relaxation

1986; Volume: 90; Issue: 12 Linguagem: Inglês

10.1002/bbpc.19860901203

0005-9021

Jolien van Breen, D. van Duijn, J. De Bleijser, J. C. Leyte,

Thermodynamic properties of mixtures

Abstract The local polymer dynamics of polyethyleneoxide in aqueous solutions were studied by 1 H‐ and 13 C‐nuclear magnetic relaxation. The concentration dependence is caused by polymer‐polymer interactions, whereas in the concentration independent range the polymer dynamics is mainly determined intramolecularly and by water‐PEO interactions. The latter interaction is influenced by the presence of salts. MW‐dependence of the relaxation rates is not observed for D P > 100. From the dispersion of the 1 H relaxation rates, for a PEO‐sample with D P = 360 at a concentration of 0.5 mol/kg, the polymer segment dynamics are evaluated in terms of an overall and an internal motion.