Primitive chain network simulations for entangled DNA solutions.
Molecular theories for polymer rheology are based on conformational dynamics of the polymeric chain. Hence, measurements directly related to molecular conformations appear more appealing than indirect ones obtained from rheology. In this study, primitive chain network simulations are compared to experimental data of entangled DNA solutions [Teixeira et al., Macromolecules 40, 2461 (2007)]. In addition to rheological comparisons of both linear and nonlinear viscoelasticities, a molecular extension measure obtained by Teixeira et al. through fluorescent microscopy is compared to simulations, in terms of both averages and distributions. The influence of flow on conformational distributions has never been simulated for the case of entangled polymers, and how DNA molecular individualism extends to the entangled regime is not known. The linear viscoelastic response and the viscosity growth curve in the nonlinear regime are found in good agreement with data for various DNA concentrations. Conversely, the molecular extension measure shows significant departures, even under equilibrium conditions. The reason for such discrepancies remains unknown.
Institute for Chemical Research, Kyoto University, Gokasyo, Uji, Kyoto 611-0011, Japan. mas@scl.kyoto-u.ac.jp
Yuichi
Y
Masubuchi
Kenji
K
Furuichi
Kazushi
K
Horio
Takashi
T
Uneyama
Hiroshi
H
Watanabe
Giovanni
G
Ianniruberto
Francesco
F
Greco
Giuseppe
G
Marrucci
D003198:Computer Simulation; D004247:DNA / Q000737:chemistry*; D004548:Elasticity; D008122:Local Area Networks; D008956:Models, Chemical; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry; D033081:Shear Strength; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties; D014783:Viscosity
D011108:Polymers; D012996:Solutions; D004247:DNA