Mechanical Response of Polyethylene Foams with High Densities and Cell Sizes in the Microcellular Range

Abstract

This article presents the compressive mechanical response at low strains for a collection of polyethylene foams with high densities and cell sizes in the microcellular range. The materials under study had a relative density between 0.27 and 0.92, a homogeneous and multi-structured cellular structure with a dense skin and a foamed core. The Young’s modulus and collapse stress were reduced when density did, the modulus following a linear trend and the collapse stress a quadratic tendency. For relative densities higher than 0.7, the materials showed Young’s modulus slightly above the limit given by a potential law with exponent equal to one. In addition, it has been proved that variations in the cell size did not influence the elastic properties. The advantages of using these materials for flat structural panels have been analyzed. A reduction of the weight of flat panels loaded in bending of up to 35% can be reached by using these foams in spite of the solid sheet from which the foam was produced.