The energy equation for mixtures can be written for polymers in the form:

By analogy to the development of the Scatchard-Hildebrand theory, this can be rearranged to:

where

N_di = degree of polymerization for the ith component

ρ = molar density

x_i = mole fraction of the ith component

N_A =­ Avogadro¡¦s number

U = molar internal energy.

a_ii* = 3 + 2/Ndi

a_ij* = a_ii* a_jj*)1/2

σ_ij³ = (σ_i³ + σ_i³ )/2

ε_ij = (ε_ii ε_jj)1/2

Derive an expression for ln γ₁ for the activity coefficient model presented above.

Transcribed Image Text:

U-Uig RT – Nu; RT ΣΣ...Na Naf- 2 Amr dr