The solubility of a substance B can be related to the square of the difference between the solubility parameters for supercooled liquid B and solvent at a given temperature, with appropriate
allowances for entropy of mixing. Thus, a value can be estimated from the solubility of the solid in a series of solvents of known solubility parameter. For a polymer, it is usually taken to be the value of the solubility parameter of the solvent producing the solution with maximum intrinsic viscosity or maximum swelling of a network of the polymer. See J.H. Hildebrand, R.L.Scott, The Solubility of Nonelectrolytes, 3rd ed., Reinhold Publishing (1950); Dover Publications (1964), Chap. VII, p.129; Chap.
XXIII, for the original definition, theory, and extensive examples.
The SI units are
but units used frequently are
The unit calorie is discouraged as obsolete.
PAC, 2008, 80, 233
(Glossary of terms related to solubility (IUPAC Recommendations 2008))
on page 264