Fracture of soft cellular solids - Case of non-crosslinked polyethylene foam

Fracture mechanical properties of hard cellular solids (porous materials) with the Young modulus E larger than 3000MPa have been well understood; scaling relations between fracture mechanical quantities and porosity are established, which can be explained by a theory based on the geometrical parameters of a cellular solid. In this study, we obtain experimentally the fracture energy of a very soft polyethylene foam with E around 1 MPa. We find scaling laws different from those for hard foams, which can be understood by considerations independent of the structural parameters of foams.