High density polyethylene (HDPE) foams (450-950 kg/m(3)) were prepared by compression molding and their tensile moduli were measured in order to study the normalized elastic modulus as a function of the normalized density of closed-cell foams. The tensile data were then used to compare several models of cellular materials and polymer composites to determine which would fit our results. Of all models used, the simple empirical equation of Moore (square power-law) and the differential scheme predict the data very well in the range of voids volume fraction under study (0-55%). (C) 2003 Wiley Periodicals, Inc.