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Equilibrium Onions?

L. Ramos·D. Roux·P. D. Olmsted·M. E. Cates
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Abstract

We demonstrate the possibility of a stable equilibrium multi-lamellar (``onion'') phase in pure lamellar systems (no excess solvent) due to a sufficiently negative Gaussian curvature modulus. The onion phase is stabilized by non-linear elastic moduli coupled to a polydisperse size distribution (Apollonian packing) to allow space-filling without appreciable elastic distortion. This model is compared to experiments on copolymer-decorated lamellar surfactant systems, with reasonable qualitative agreement.

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L. Ramos, D. Roux, P. D. Olmsted, M. E. Cates. 2004-07-01. Equilibrium Onions?. https://doi.org/10.1209/epl%2Fi2003-10260-6

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