Efforts toward an Exact Kirkwood-Riseman Theory of the Intrinsic Viscosity

Abstract

A new, formally exact formula is derived for the steady-flow Newtonian intrinsic viscosity of a polymer chain. The result is expressed as a sum of two terms: One is an upper bound for the exact intrinsic viscosity and requires the evaluation of only two kinds of equilibrium moments of the friction tensor. The other involves the velocities of the chain segments and vanishes only if the molecule rotates as a whole around its center of mass with the rotational component of the solvent flow. The upper bound formula is found to give the known exact results for the rigid rod, polygon, and dumbbell models and to be a very good approximation for nearly rigid dumbbells. By explicit calculation for the stiff dumbbell model it is also shown that the coupling between chain flexibility and hydrodynamic interactions causes segment motions to deviate from the rotational component of the solvent flow.

Department(s)

Physics

International Standard Serial Number (ISSN)

0024-9297

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 1981 American Chemical Society (ACS), All rights reserved.

Publication Date

01 Sep 1981

Share

 
COinS