Fluctuations in the coil-stretch transition of flexible polymers in good solvents: a peak due to nonlinear force relation.
Long flexible polymers undergo a coil to stretch transition (CST) in an elongational flow. Near the CST, a peak can be observed in the fluctuations of the size of a molecule (|R|). Solvent effects on the fluctuations are studied using Brownian dynamics simulations of a nonlinear spring force relation that can represent real molecules. Ignoring the influence of hydrodynamic interactions, a linear region in the spring force relation is known to cause the peak in |R| fluctuations. In contrast, we find that a peak in the fluctuations can be obtained even for the nonlinear spring force relation. We analyze the influence of hydrodynamic interactions on the fluctuations using a dumbbell model with a conformation-dependent drag coefficient.
Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, 110 8th St, Troy, New York 12180, USA.
Rangarajan
R
Radhakrishnan
Patrick T
PT
Underhill
D057446:Hydrodynamics; D008958:Models, Molecular; D008968:Molecular Conformation; D017711:Nonlinear Dynamics; D011108:Polymers / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*
D011108:Polymers; D012997:Solvents