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arXiv · 2401.17551

Polymer Network Diffusion in Charged Gels

Shoei Sano·Takashi Yasuda·Takeshi Fujiyabu·Naoyuki Sakumichi·Takamasa Sakai
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Abstract

The swelling kinetics of charged polymer gels reflect the complex competition among elastic, mixing, and ionic contributions. Here, we used dynamic light scattering to investigate the collective diffusion coefficient of model gels, whose polymer network structure was controlled so that the three contributions were comparable. We demonstrate that the collective diffusion coefficient stems from the sum of elastic, mixing, and ionic contributions, without evident cross-correlations. The significant ionic contribution conforms to the Donnan equilibrium, which explains equilibrium electrical potential gradients in biological systems.

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Shoei Sano, Takashi Yasuda, Takeshi Fujiyabu, Naoyuki Sakumichi, Takamasa Sakai. 2024-01-31. Polymer Network Diffusion in Charged Gels. https://arxiv.org/abs/2401.17551

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