Extension to many-component polymer solutions and blends

3 Extension to many-component polymer solutions and blends 

Similar consideration of the configurational entropy to arrange two species of polymers with n and 2 repeat units leads to the free energy of mixing per lattice site. 

In particular, for a symmetric blends for which =M2 is satisfied, they are reduced to 0c = 1/2, Xc=2/n. 

We can extend the theory still further to the many-component polymer blends whose components are indicated by i (= l,2.c), each carrying n, repeat units. The free energy per lattice site is 

In particular, for the three-component blends P1/P2/P3, the Gibbs determinant is 

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