The so-called "plastic modification" means adding one or more other substances into plastic resin to change its original properties and improve one or more properties, so as to expand its application scope. Modified plastic materials are collectively referred to as "modified plastics". There are several ways to modify plastics: 1, reinforcement: the purpose of increasing the rigidity and strength of materials is achieved by adding fibrous or flaky fillers such as glass fiber, carbon fiber and mica powder. Such as glass fiber reinforced nylon for power tools. 2. Toughening: The purpose of improving the toughness/impact strength of plastics is achieved by adding other substances such as rubber and thermoplastic elastomer, such as toughened polypropylene commonly used in automobiles, household appliances and industrial applications. 3.* * * Mixing: Two or more incompatible polymer materials are evenly mixed into a mixture with macroscopic compatibility and microscopic phase separation. The method meets some requirements of physical and mechanical properties, optical properties and processing properties. 4. Alloy: similar to * * * blend, but with good compatibility between components, it is easy to form a homogeneous system, and it can obtain some properties that cannot be achieved by a single component, such as PC/ABS alloy or PS modified PPO. 5. Filling: The purpose of improving physical and mechanical properties or reducing costs is achieved by adding fillers into plastics. Adding antioxidant/light stabilizer to improve the weather resistance of the material; Adding pigments/dyes to change the color of materials, adding internal/external lubricants to improve the processability of materials, and using nucleating agents to change the crystallization characteristics of semi-crystalline plastics to improve their mechanical and optical properties. In addition to the above physical modification methods, there are also methods to modify plastics through chemical reactions to obtain specific properties. For example, maleic anhydride grafted polyolefin, cross-linking of polyethylene, peroxide degradation resin used in textile industry to improve fluidity/fiber-forming performance and so on. In industry, many modification methods are often used together, such as adding toughening agent such as rubber in the process of plastic reinforcement and modification, so as not to lose too much impact strength; Or both physical mixing and chemical crosslinking (TPV) exist in the production of thermoplastic vulcanized rubber.