Osmotic pressure and swelling near the critical point

6 Osmotic pressure and swelling near the critical point 

These are the formulae which we shall use to study the experimental results. The critical temperature Tf is given by the conditions 

For a finite chain, Tgf(S) is the temperature for which 3E0 = °40(y), because this swelling is also the swelling or an infinite chain at temperature TF (see Section 2.2) the corresponding value z,F(S) of z is given by 

The result (14.6.57) is not trivial and can be obtained only after elimination of the short-range divergences (for instance, by analytic continuation as we did here). The older theory of Flory, which does not recognize this necessity, gives opposite inequalities it seems that the same effect occurs for the decimation theory presented by de Gennes in his book6 (see, in particular, his Fig. 11.6). 

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