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Self-assembly of 2D membranes from mixtures of hard rods and depleting polymers().

ABSTRACT: We combine simulations and experiments to elucidate the molecular forces leading to the assembly of two dimensional membrane-like structures composed of a one rod-length thick monolayer of aligned rods from an immiscible suspension of hard rods and depleting polymers. Computer simulations predict that monolayer membranes are thermodynamically stable above a critical rod aspect ratio and below a critical depletion interaction length scale. Outside of these conditions alternative structures such as stacked smectic columns or nematic droplets are thermodynamically stable. These predictions are confirmed by subsequent experiments using a model system of virus rod-like molecules and non-adsorbing polymer. Our work demonstrates that collective molecular protrusion fluctuations alone are sufficient to stabilize membranes composed of homogenous rods with simple excluded volume interactions.

SUBMITTER: Yang Y

PROVIDER: S-EPMC3489486 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Self-assembly of 2D membranes from mixtures of hard rods and depleting polymers().

Yang Yasheng Y Barry Edward E Dogic Zvonimir Z Hagan Michael F MF

Soft matter 20111107 3

We combine simulations and experiments to elucidate the molecular forces leading to the assembly of two dimensional membrane-like structures composed of a one rod-length thick monolayer of aligned rods from an immiscible suspension of hard rods and depleting polymers. Computer simulations predict that monolayer membranes are thermodynamically stable above a critical rod aspect ratio and below a critical depletion interaction length scale. Outside of these conditions alternative structures such a ...[more]

PMID: 23139699

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