Foam characterization and quantitative stereology

Abstract

The basic concepts of quantitative stereology are introduced and how stereology relates morphology to a statistical characterization of foams is described. The stereological parameters for the foam system are obtained with a computer-interfaced optical microscope and are calculated by traditional methods for either static or dynamic systems and for either polymeric or nonpolymeric foams. These foam parameters are used either individually or in combination to provide an additional perspective on the mechanism of foam formation and stability. Finally, they serve to generate correlations with physical test values associated with the bulk foam behavior.

Substituting soybean oil-based polyol into polyurethane flexible foams

“…The perimeters of cells were manually traced from the SEM micrographs using UTHSCSA ImageTool software (Microsoft Corporation). Individual cell size was then calculated by approximating the cells as circular shapes [24,25]. Average cell diameter and cell size standard deviation were calculated from a survey of over 40 cells.…”

The 3D structure of real polymer foams

“…Previous studies using 2D image processing to automate foam measurement collected data in a fraction of the time required for physical inspection. In most earlier studies using automated image analysis to extract structural information; however, only one or a few structural measurements were compared to physical properties [15][16][17]. Furthermore, the use of different standards for even simple measurements such as cell diameter [18] makes it difficult to compare the results of similar studies to develop a body of structure-property knowledge.…”

X-Ray Computed Tomography on a Cellular Polysiloxane under Compression

“…The foam characterization methods developed by Delesse [7] and later carried forward by Rhodes and Khaykin [8] use stereology to project two-dimensional feature information into a three-dimensional space. As described earlier, one can imagine a cube cut from the specimen and a grid superimposed upon a bisecting plane (see Figure 2).…”

“…(It should be noted that the term n is equivalent to the relative density, ρ*/ρ, as described by Gibson and Ashby [5].) For sphere-shaped cells, (8) ( )…”