The main toughening agents for PA66 are non-polar polyolefins (PP, PE) and elastomers (EPDM, POE). PA66 has polarity, and it has poor compatibility with non-polar substances such as PP and PE. PP and PE are unevenly dispersed in the system PA66/PP and PA66/PE, the molecules are agglomerated, the interface is clear, and the mechanical properties are not good. In the PA66/EPDM and PA66/POE systems, EPDM and POE will break the chain to generate free radicals at high temperature, and the molecules will react with each other to form cross-linked macromolecules, resulting in poor compatibility between the matrix and the dispersed phase, and poor overall performance of the material. The maleic anhydride (MAH) molecule has polarity and is a good compatibilizer for PA66. The MAH interface bonding energy is relatively large. The toughening agent grafts MAH, which can enhance the polarity of the toughening agent and the active group in the MAH molecule. Can be combined with PA66 amide
A chemical reaction occurred. The addition of the compatibilizer MAH increases the notched impact strength of the composite, but if the MAH is excessive, it will self-polymerize and also cause the toughening agent to crosslink the gel.
