Blob Size Controls Diffusion of Free Polymer in a Chemically Identical Brush in Semidilute Solution.
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ABSTRACT:
SUBMITTER: Zhang ZJ
PROVIDER: S-EPMC6117105 | biostudies-literature | 2018 Aug
REPOSITORIES: biostudies-literature
Publications
Blob Size Controls Diffusion of Free Polymer in a Chemically Identical Brush in Semidilute Solution.
Zhang Zhenyu J ZJ Edmondson Steve S Mears Matthew M Madsen Jeppe J Armes Steven P SP Leggett Graham J GJ Geoghegan Mark M
Macromolecules 20180810 16
The diffusion of rhodamine-labeled poly(ethylene glycol) (r-PEG) within surface-grafted poly(ethylene glycol) (s-PEG) layers in aqueous solution at 18 °C was measured by fluorescence correlation spectroscopy. The diffusion coefficient of r-PEG within s-PEG was controlled by the grafting density, σ, and scaled as σ<sup>-1.42±0.09</sup>. It is proposed that a characteristic blob size associated with the grafted (brush) layer defines the region through which the r-PEG diffusion occurs. The diffusio ...[more]
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