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arXiv · 0804.1052

Swelling and shrinking kinetics of a lamellar gel phase

David J Fairhurst·Mark E Baker·Neil Shaw·Stefan U. Egelhaaf
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Abstract

We investigate the swelling and shrinking of L_beta lamellar gel phases composed of surfactant and fatty alcohol after contact with aqueous poly(ethylene-glycol) solutions. The height change $\Delta h(t)$ is diffusion-like with a swelling coefficient, S: $\Delta h = S \sqrt{t}$. On increasing polymer concentration we observe sequentially slower swelling, absence of swelling, and finally shrinking of the lamellar phase. This behavior is summarized in a non-equilibrium diagram and the composition dependence of S quantitatively described by a generic model. We find a diffusion coefficient, the only free parameter, consistent with previous measurements.

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David J Fairhurst, Mark E Baker, Neil Shaw, Stefan U. Egelhaaf. 2008-04-07. Swelling and shrinking kinetics of a lamellar gel phase. https://doi.org/10.1063/1.2913762

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