Statistical mechanical theory for liquid‐crystalline polymer solutions

Sato, Takahiro; Teŕamoto, Akio

doi:10.1002/actp.1994.010450601

Cited by 47 publications

(99 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…8 The concentration dependence of their D s was stronger than that ofD D obtained by Roots et al 23 for the same polymer, in accordance with our results for fraction F16. On the other hand, Brown et al 7,13,14,24 In a previous paper, 15 the zero-shear viscosity of THF solutions of CTC were demonstrated to be favorably compared with the prediction of the fuzzy cylinder theory. Here we compare the diffusion coefficient data obtained in this study with the same theory.…”

Section: Light Scatteringmentioning

confidence: 99%

“…for stiff or semiflexible polymers in solution ranging from dilute through concentrated (isotropic) regimes. 14 The jamming effect on D k can be treated on the basis of the hole theory, which gives the following equation 13,14 …”

Section: Fuzzy Cylinder Theorymentioning

confidence: 99%

“…is treated by a mean-field Green function method, 25,26 The final expression for D ? read 14,24 Inserting eqs 8 and 9 with eq 10 into eq 7 and expanding this equation in terms of the power series of c, we have…”

Section: Fuzzy Cylinder Theorymentioning

confidence: 99%

“…This polymer was molecularly well characterized in the previous study. 12 By dynamic light scattering, static light scattering, and pulsed field gradient NMR (PFG-NMR), we have determined D m , @Å=@c, and D s , respectively, as functions of the concentration and molecular weight of CTC, and compared experimental D D and D s , as well as the fuzzy cylinder theory 13,14 for D s which was favorably compared withD D for PHIC solutions. 7 …”

mentioning

confidence: 99%

See 3 more Smart Citations

Mutual- and Self-Diffusion Coefficients of a Semiflexible Polymer in Solution

Kanematsu

Sato

Imai

et al. 2005

Polym J

View full text Add to dashboard Cite

ABSTRACT:Mutual-and self-diffusion coefficients of a semiflexible polymer, cellulose tris(phenyl carbamate) (CTC), in tetrahydrofuran were measured by dynamic light scattering and pulsed field gradient NMR, respectively, as functions of the polymer concentration and molecular weight. The mutual-diffusion coefficient after elimination of the effects of thermodynamic force and solvent back flow agrees with the self-diffusion coefficient for a low molecular weight CTC fraction with the number of Kuhn's statistical segments N ¼ 1:8 up to high concentrations, but they disagree for a higher molecular weight CTC fraction with N ¼ 4:7 at the highest concentration investigated. The mutual diffusion coefficients for CTC fractions with N ranging from 1.8 to 10.6 after elimination of the above two effects were also compared with the fuzzy cylinder theory for the self-diffusion coefficient. Disagreements start at lower concentration for larger N, which form in a contrast with good agreements for a more stiff polymer, poly(n-hexyl isocyanate), previously studied. [DOI 10.1295/polymj.37.65] KEY WORDS Mutual-Diffusion Coefficient / Self-Diffusion Coefficient / Dynamic Light Scattering / Pulsed Field Gradient NMR / Semiflexible Polymer / Cellulose Derivative / There are two kinds of translational diffusion coefficients for binary solution systems: the mutual-diffusion coefficient D m and the self-diffusion coefficient D s .1-3 The conventional concentration gradient method provides the former diffusion coefficient. Dynamic light scattering is a more convenient method to determine D m , where the concentration gradient is generated by thermal fluctuation. On the other hand, a certain solute molecule is labeled, and the Brownian motion of the labeled molecule (the tracer) is monitored by some method to measure the latter diffusion coefficient D s . Forced Rayleigh scattering, fluorescence recovery after photobleaching, pulsed field gradient NMR, and so on belong to techniques to measure D s .3,4 These two diffusion coefficients are identical at infinite dilution, but they often exhibit opposite concentration dependencies.The mutual and self diffusions occur under different experimental conditions. While the solution is thermodynamically homogeneous during the measurement of D s , the concentration gradient is necessary to measure D m . The concentration gradient provides a thermodynamic force to make a macroscopic flow of the solute at a finite concentration, and the solute flow is accompanied by the solvent back flow to maintain the constant density of the solution. The thermodynamic force and the solvent back flow discriminate D m from D s , and the two effects may be eliminated by use of the following equation:where M, c, and " v v are the molecular weight, the mass concentration, and the partial specific volume of the solute, respectively, RT is the gas constant multiplied by the absolute temperature, and Å is the osmotic pressure. The effects of the thermodynamic force and the solvent back flow are taken into account by the...

show abstract

Section: Light Scatteringmentioning

confidence: 99%

Section: Fuzzy Cylinder Theorymentioning

confidence: 99%

Section: Fuzzy Cylinder Theorymentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Mutual- and Self-Diffusion Coefficients of a Semiflexible Polymer in Solution

Kanematsu

Sato

Imai

et al. 2005

Polym J

View full text Add to dashboard Cite

show abstract

“…1,2 Semiflexible polymers can exhibit liquid crystalline order [3][4][5][6] and hence are promising building blocks in various applications. 7,8 Also many constituents of living matter are semiflexible macromolecules, e.g., double-stranded (ds) DNA and actin, which play a central role for the structure and function of cells.…”

Section: Introductionmentioning

confidence: 99%

Conformations and orientational ordering of semiflexible polymers in spherical confinement

Milchev

Егоров

Nikoubashman

et al. 2017

The Journal of Chemical Physics

View full text Add to dashboard Cite

Semiflexible polymers in lyotropic solution confined inside spherical nanoscopic "containers" with repulsive walls are studied by molecular dynamics simulations and density functional theory, as a first step to model confinement effects on stiff polymers inside of miniemulsions, vesicles, and cells. It is shown that the depletion effects caused by the monomer-wall repulsion depend distinctly on the radius R of the sphere. Further, nontrivial orientational effects occur when R, the persistence length p , and the contour length L of the polymers are of similar magnitude. At intermediate densities, a "shell" of wallattached chains is forming, such that the monomers belonging to those chains are in a layer at about the distance of one monomer from the container wall. At the same time, the density of the centers of mass of these chains is peaked somewhat further inside, but still near the wall. However, the arrangement of chains is such that the total monomer density is almost uniform in the sphere, apart from a small layering peak at the wall. It is shown that excluded volume effects among the monomers are crucial to account for this behavior, although they are negligible for comparable isolated single semiflexible chains of the same length. Published by AIP Publishing. [http://dx

show abstract