Equilibrium phase diagram of semi-flexible polymer networks with linkers

We present the determination by numerical simulation of the equilibrium phase diagram of solutions of semi-flexible polymers with linker molecules. At low linker concentrations the solution forms an isotropic gel phase. At higher linker concentrations we encounter —depending on the properties of the linker molecules— bundle phases, liquid-crystalline mesophases with broken bond-orientational order that had been predicted by analytical theories, and in addition a novel equilibrium state: the cluster phase. Equilibrium condensation of semi-flexible polymers appears to be controlled by linker entropy. The results are compared with the phase behavior of solutions of biopolymers and linker proteins.

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