Theories in Relation to Intrinsic Viscosity of Flexible Chains

5 Theories in Relation to Intrinsic Viscosity of Flexible Chains 

According to Kirkwood and Riseman, the frictional force F exerted on the surrounding medium by the bead I due to the motion of the chain in the medium may be expressed as 

FIGURE 8.5 Pearl string model A, solvent molecule 0 monomeric unit. 

In these equations, N is the Avogadro number, b is the effective bond length of the chain, N is the number of links in the polymer molecule, M is the molecular weight of the polymer, and Mo is the molecular weight of the monomer unit. The function F(koN ) is theoretically tabulated. Its value is between 0 and 1. 

according to this theory, at a given molecular weight, the intrinsic viscosity [r]] is related to N by the frictional coefficient / of a monomer unit and the effective bond length b of the chain. As N approaches infinity, [rj] becomes independent of / and the above equation may be simplified to 

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