A unit cell of a specified shape under specified loading conditions has been offered for predicting some basic properties of particulate polymeric composites. The stress-strain state of the bonded and debonded cell has been calculated in the framework of the large deformation approach within a wide range of filler volume concentrations. Effective modulus-filler concentration curves have been predicted on the basis of the unique cell investigation for bonded and debonded cell states and have proved to be in good agreement with the available experimental data Local strain concentration as a function of cell extension and filler volume loading has been estimated.