Short Intrinsic viscosity, effect

The introduction of succinyl residues producing short-range repulsive forces in place of possible short-range attractive forces in the native molecule resulted in a change of hydrodynamic properties of bovine serum albumin (BSA), bovine y-globulin, and /3-lactoglobulin [3], The succinylated derivatives showed markedly increased intrinsic viscosity and Stokes radius and a decrease of sedimentation coefficient [36,37], These results are compatible only with a considerable increase in the effective volume occupied by the succinylated protein molecule compared to its unreacted counterpart. 

Solution properties of the polymers are primarily determined by the high polyethylene content, and at the concentrations present short-chain branching is assumed to have little or no effect on chain dimensions and hence intrinsic viscosity. Accordingly, SEC analyses of LLDPE have invariably been carried out assuming that the molecules elute as linear polyethylene. 

The shape of the particles also has an effect on the viscosity. Most advanced ceramics are fabricated using nearly equiaxial particles, but the effect of shape would be important, for example, in the colloidal processing of ceramic composites reinforced with whiskers (short single crystal fibers) or platelets. Figure 4.43 shows the results of theoretical calculations for the intrinsic viscosity [i)] as a function of the axial ratio for particles with the shape of prolate ellipsoids. For an axial ratio of 15-20, which may be relevant to the use of whiskers or platelets in ceramic composites, the results show that [t ] has a value of —4.5 compared to 2.5 for spherical particles. 

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