The Ideal Viscosity Correlation by Einstein

The viscosity enhancing properties of a polymer coil can be described via a Tay-lor-series  

Here the fraction of the polymer in solution is given by the volume fraction (jn 

Fortunately, all higher powers in Eq. (4.1) can be disregarded for an ideal state of dilution According to Einstein, the polymer coils are assumed to be perfectly inelastic and behave like hard spheres. Therefore, the following simple (and experimentally confirmed) relationship is obtained  

The volume of the polymer coils l poiymer can be described via the ratio of the mass polymer of t e polymer to its density Pequ- This density p qu does not correspond with the density in the dry state, but with the density of the polymer in solution, where solvent molecules surround the polymer chain  

The specific viscosity, introduced in Chap. 2 still depends on the concentration according to Eq. (4.5). In order to obtain the true viscosity enhancing properties of a polymer, the reduced viscosity is introduced  

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