Mechanical and transport properties of polymeric foams derived from 3D images

Manufactured cellular materials (e.g., polymer, ceramic or metallic foams) are an extremely attractive option as materials engineered for a range of applications ranging from lightweight structures to packaging, insulation and crash protection. Many useful properties of cellular solids are a direct consequence of their microstructure. It is important therefore to link the physical properties of cellular solids to their density and complex microstructure in order to understand how their structure can be optimised for a given application. We demonstrate a 3D imaging technique and the ability to calculate thermal conductance and elastic properties of a number of industrial cellular foam polymers. We compare our numerical data to commonly used theoretical and empirical property-porosity relationships. For conductivity we find that the numerical results agree extremely well with an empirical expression based on experimental data of various foams. The upper Hashin-Shtrikman bound also provides an excellent prediction of the data across all densities.