It is essential to improve the fracture toughness of polypropylene (PP).While the addition of an elastomer is one of the most effective methods, typical concentrations of more that 15wt% of elastomer and sometimes as high as 40wt%, render the toughness improvement unviable.Another method however, which uses far less additive to improve fracture toughness of PP is what is referred to as phase transformational toughening where the semi-crystalline structure is transformed from a primarily α phase to the tougher β phase.