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Local entropic effects of polymers grafted to soft interfaces

T. Bickel·C. Jeppesen·C. M. Marques
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Abstract

In this paper, we study the equilibrium properties of polymer chains end-tethered to a fluid membrane. The loss of conformational entropy of the polymer results in an inhomogeneous pressure field that we calculate for gaussian chains. We estimate the effects of excluded volume through a relation between pressure and concentration. Under the polymer pressure, a soft surface will deform. We calculate the deformation profile for a fluid membrane and show that close to the grafting point, this profile assumes a cone-like shape, independently of the boundary conditions. Interactions between different polymers are also mediated by the membrane deformation. This pair-additive potential is attractive for chains grafted on the same side of the membrane and repulsive otherwise.

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T. Bickel, C. Jeppesen, C. M. Marques. 2000-06-06. Local entropic effects of polymers grafted to soft interfaces. https://doi.org/10.1007/s101890170140

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