On the coarse-graining of polymers into bead-spring chains
نویسندگان
چکیده
We present a study of the coarse-graining of polymers into bead-spring chains using statistical mechanics. The force–extension behavior is examined at different levels of coarse-graining. A direct result of the springs being decoupled is that the force–extension behavior depends only on the number of flexibility lengths (e.g. persistence or Kuhn lengths) represented by each spring. This dimensionless parameter is found to govern the fluctuations around the mean extension, analogous to the conventional role of temperature. The use of an effective flexibility length to correct the model behavior is analyzed, and we have calculated bounds on the choices of this correction factor. The analytic nature of the statistical mechanical framework has also allowed for the calculation of asymptotic and universal behavior. The zero Weissenberg number rheological b s i c l d ©
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