Flory- Rehner Equation

[Sperling-428]

The Flory-Rehner Equation is about equilibrium swelling theory
1 The first term, reading left to right, contains the number 'one', not the letter 'el': "natural log of one minus nu subscript two"
is the volume fraction of polymer in the swollen mass [Sperling- 429]
is the Flory-Huggins Interaction Parameter
is the molar volume of the solvent
Flory-Rehner considers the following three ideas:
1. The entropy change caused by the mixing polymer and solvent
  - this entropy change is positive and favors swelling
2. The entropy change caused by the reduction in the number of possible chain conformations as the polymer network swells
  - this entropy change is negative and discourages swelling
3. The heat of the mixing of polymer and solvent
  - Usually, but not always, slightly positive, and it opposes mixing.

Last Update- September 1, 1995- wld