Fig. 2. The Poisson’s ratio of experimental foam networks aged under pure shear strain.

The abscissa is the strain at which Poisson’s ratio is measured when the network is compressed along a given direction. The unaged (circles) networks do not show a substantial dependence on measurement strain along either axis. The aged networks (triangles) show a marked change in behavior when ν is measured by compressing along the pulling axis (blue) or along the axis that was compressed (red) during aging.