Title

Transport of Small Molecules in Swollen Polymer Beads

Abstract

Pulsed-field-gradient spin-echo (PGSE) NMR experiments have been used to determine self-diffusion coefficients of toluene in swollen cross-linked polystyrene beads with 5.7-40% cross-linking. Self-diffusion coefficients were also determined for toluene in linear polystyrene solutions over a concentration range of 0.1-0.7 weight fraction of polymer. The swelling ratios of the cross-linked beads were used to determine the concentration of toluene in the beads by assuming that the increase in volume is due only to solvent uptake. A comparison of solvent diffusion in the cross-linked and the non-cross-linked systems at similar concentrations shows remarkably close agreement. These results suggest that the diffusion rate in the cross-linked polymer beads is not significantly affected by the presence of cross-links and is mainly determined by the concentration of solvent in the bead.

Department(s)

Chemistry

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 1986 American Chemical Society (ACS), All rights reserved.


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