New insights into Hansen's solubility parameters

Correlations among the three components, δ_d² (dispersion), δ_h² (hydrogen‐bonding), and δ_p² (polar) that make up the Hansen solubility parameter equation, δ_o² = δ_d² + δ_h² + δ_p², have been analyzed for a large number of organic solvents. A relationship is found that enables δ_h and δ_p to be estimated if δ_o and δ_d are known. This relationship is applied to a variety of common polymers and remarkably good agreement is obtained with tabulated values for δ_h and δ_p. Additional correlations are found that can be expressed in approximate functional form. The analysis also reveals relationships, expressed as inequalities, among the parameters that limit their range of possible values. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 4337–4343, 2004