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arXiv · 1109.5658

Entropic force of polymers on a cone tip

Mohammad F. Maghrebi·Yacov Kantor·Mehran Kardar
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Abstract

We consider polymers attached to the tip of a cone, and the resulting force due to entropy loss on approaching a plate (or another cone). At separations shorter than the polymer radius of gyration R_g, the only relevant length scale is the tip-plate (or tip-tip) separation h, and the entropic force is given by F=A kT/h. The universal amplitude A can be related to (geometry dependent) correlation exponents of long polymers. We compute A for phantom polymers, and for self-avoiding (including star) polymers by epsilon-expansion, as well as by numerical simulations in 3 dimensions.

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Mohammad F. Maghrebi, Yacov Kantor, Mehran Kardar. 2011-12-13. Entropic force of polymers on a cone tip. https://doi.org/10.1209/0295-5075%2F96%2F66002

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