The current paper presents an experimental study of the residual stress role to recover polymer blend to its original position after deformation. A mixture of 40% PolyCaproLactone (PCL) and 60% Styrene-Butadiene-Styrene (SBS) is used for our study. The Shape Memory Polymer (SMP) is able to storing a permanent macroscopic after passing through a temporary one; then under an external stimulus; they can recover their initial shapes. The recovery rate depends not only on the mechanical property of the mixture, but also the number of the loading cycles. Indeed, one multiplying the number of mechanical loading cycle; generally tensile test; the recovery rate does not change in a linear manner and therefore the residual stress is not added in integer from one cycle to another. In this work we studied the mechanism of the shape as well as properties memory effect of the blend under study during a shape memory cycle, to establish a relationship between the “shape memory effect” and the “properties memory effect”. Finally, we measure the “Driving Force” responsible for the shape memory effect by an original method. This study allows establishing a relationship between the rate of recovery and residual stresses introduced into the polymer during its deformation.