The Influence of Porosity on Stress and Strain State of Porous Polymer Materials

Abstract

The determination of microstructure influence on porous materials macro properties can be applied to predict behaviour of material. The numerical finite element method was used to identify stress and strain state in porous polymer material microstructure in dependence on porosity value and mode under tensile loading by constant force. The highest local stress values were found in the free surface of polymer located at the boundary with pore. Both pores size and their distribution mode influence values of the stress. The stresses and deformability increase with increasing porosity value. The lowest deformability and stress values were obtained up to material porosity 0.5. In this case influence of porosity mode on the stress and strain state is insignificant. The high material porosity (γp > 0.5) and the absence of large interpores zones cause the relatively low stress values and high deformability of material.