![]() (1955) "Non-Newtonian Viscosity of Solutions of Ellipsoidal Particles", J. (1940) "Viscosity and the Shape of Protein Molecules", Science, 92, 132-133. The intrinsic viscosity is then determined from the y-intercept of a plot of red versus c by extrapolating the linear fit of the data to c 0 i.e. (1940) "The Influence of Brownian Movement on the Viscosity of Solutions", J. A linear dependency of the reduced viscosity red from the concentration c is evident, with a k 2 being the slope and b the y-intercept ( red b + a c). ![]() (1922) "The Motion of Ellipsoidal Particles Immersed in a Viscous Fluid", Proc. The val-ue for the intrinsic viscosity is obtained by plot-ting Equations 1, 4, or 5 and extrapolating to con-centration zero. In polymer chemistry intrinsic viscosity is related to molar mass through the Mark-Houwink equation.A practical method for the determination of intrinsic viscosity is with a Ubbelohde viscometer. viscosity (5) K H, K K and K SB represent the Huggins, Kraemer and Schulz-Blaschke non-dimensional constants, respectively, and h is the intrinsic viscosity with units inverted to concentration (mL/g). More generally, intrinsic viscosity can be used to assay quaternary structure. For example, the intrinsic viscosity can provide rough estimates of the number of subunits in a protein fiber composed of a helical array of proteins such as tubulin. The intrinsic viscosity is very sensitive to the axial ratio of spheroids, especially of prolate spheroids. The intrinsic viscosity formula may also be generalized to include a frequency dependence. It is possible to generalize the intrinsic viscosity formula from spheroids to arbitrary ellipsoids with semiaxes a, b and c. The J coefficients are the Jeffery functions General ellipsoidal formulae The effects of chemical structure and molecular weight on the polymer/. Molasses, for example, has a greater viscosity than water. The reciprocal of the viscosity is called the fluidity, a measure of the ease of flow. Generalizing from spheres to spheroids with an axial semiaxis a (i.e., the semiaxis of revolution) and equatorial semiaxes b, the intrinsic viscosity can be written This modification facilitates the use of the Fedors equation for dilute to concentrated polymer solutions for determining the intrinsic viscosity at a single. was estimated via an extrapolation procedure using the Huggins and Kramer equations. viscosity, resistance of a fluid (liquid or gas) to a change in shape, or movement of neighbouring portions relative to one another.
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