1. PP toughening and modification methods include copolymer modification, blend modification, and the addition of nucleating agents. However, research reports have focused more on the following three aspects: (1) Toughening by blending with rubber or thermoplastic elastomers; (2) Toughening with inorganic rigid particles; (3) Toughening with inorganic nanomaterials. 2. Toughening by Blending with Rubber or Thermoplastic Elastomers Blending rubber or thermoplastic elastomers into plastic as elastic micro-particles has been proven to be an effective method. This is one of the most studied and effective methods for toughening. 2.1 PP/EPDM Blend System Since both PP and EPDM contain propyl groups, according to the principle of like-dissolves-like, they should have good compatibility. Additionally, because EPDM belongs to the rubber class, it has high elasticity and good low-temperature performance, making it a good toughening modifier for PP. Blending EPDM with PP can improve the impact resistance and low-temperature brittleness of PP. 2.2 PP/POE Blend System Using EPDM, EPR, SBS, and other rubbers or thermoplastic elastomers for toughening modification can significantly improve the impact resistance of PP. However, there are several shortcomings in terms of thermal stability, weather resistance, and processability. Recently, a new type of toughening agent, POE (Polyolefin Elastomer) and POP, has emerged. These toughening agents are metallocene-catalyzed ethylene-octene or ethylene-butene copolymers, characterized by narrow molecular weight distribution, low density, balanced properties, easy processing, and high toughness, transparency, and flowability. They provide particularly noticeable toughening effects on PP, outperforming traditional toughening agents such as EPDM and EPR. Whether for general PP, copolymer PP, or high-flow PP, POE's toughening effect surpasses that of EPDM or EPR. Since POE possesses both the elasticity of rubber and the rigidity of plastics, it can maintain high modulus, tensile strength, and good processing flowability while toughening PP. Additionally, POE does not contain unsaturated double bonds, offering superior weather resistance compared to EPDM, EPR, and SBS.