Polymer solutions Flory-Huggins theory in the attractive case

POLYMER SOLUTIONS FLORY HUGGINS THEORY IN THE ATTRACTIVE CASE 

Flory-Huggins theory was studied in detail in Chapter 8, Section 2.1. We recall that in this model, N self-avoiding chains of (N — 1) links (N monomers) are 

let us examine what happens when the number N of links becomes very large. In this case, it is convenient to express the osmotic pressure in terms of the volume fraction p — NCv, (number of monomers per site) 

In this context, the Flory temperature Tv is defined by the condition that the second virial coefficient vanishes, a fact which occurs when x = 1/2. Consequently, in the vicinity of TF, we have 

When N goes to infinity, one part of the demixtion curve coincides with the axis C = 0. The limit of the demixtion curve is given by the equation II = 0 which in this case reads 

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