new class of materials featuring PP/HDPE composite matrix modified by SBS toughening agent are explored. Excellent mechanical properties are offered by the present three component blending materials. Furthermore

a systematic discussion on the toughening mechanisms of the said material system is conducted from three different but mutually connected viewpoints

namely the morphology structures

the macroscopic mechanics response and the evolution of the crack tip profile. The investigation indicates that toughening can be achieved by the super-blunted crack tip in the plane strain portion of the crack profile

and the deve-lopment of crack tip superblunting is resulted by controlling the material morphology and the suppressing on the early evolution of the dilatational defor-mation.