PA66 is a polyhexanediamide condensation polymer, commonly known as Nylon 66, PA66 for short, in the PA series is a great yield and use of a wide variety. The PA66 series and its modified varieties were formed by different polymerization processes, such as homopolymer PA66, GFPA66, toughened PA66, super-toughened PA66, flame retardant PA66 and so on. According to the molding process can also be divided into injection stage, extrusion stage, blow molding stage, and so on, in which the injection-based materials. The basic properties of PA66 are as follows: (1) the strength, rigidity, fatigue strength and creep resistance of Pa66 are better than those of PA6, the mechanical properties of PA66 are better than that of PA6, but its low temperature resistance is lower than that of PA6. (2) the molding shrinkage is higher than that of PA6, and the water absorption is lower than that of PA6. (3) PA66 has good thermal properties and high melting point, which is about 255 °C, the temperature of continuous use is 105 °C, the temperature of thermal deformation is 75 °C, but the temperature of transient heat resistance is very high, and the flame retardancy reaches UL94 V-2 grade, which is self-extinguishing low-throat plastic. (4) the electrical properties of PA66 are good; (5) the corrosion resistance of Pa66 is good; Excellent corrosion resistance to lubricants, hydraulic oils, engine oils, coolants, refrigerants, detergents, aliphatic and aromatic solvents, and corrosion resistance to dilute acid and alkali solvents, but soluble in phenol, formic acid and other polar solvents. PA66 has good resistance to hot water and steam. (6) the weather resistance of Pa66 is generally worse than that of PMMA and HDPE.