Full name in English: Polyamide 66 (PA66 for short), commonly known as nylon double 6, is a semi crystalline polyamide (nylon) engineering plastic, which is made from adipic acid+hexamethylene diamine through polycondensation. It is one of the five general engineering plastics, and its comprehensive performance is better than that of PA6 (nylon 6) Tiktok.   
1、 Basic physical properties (pure resin) 
-Density: 1.15 g/cm ³ 
-Melting point: approximately 252~260 ℃ 
-Continuous use temperature: 80-120 ℃, can withstand higher temperatures for a short period of time 
-Balanced water absorption rate: about 2.5% (water absorption will toughen, but affect dimensional stability) 
-Appearance: translucent to opaque milky white particles, color matching (black, beige, etc.) 
2、 Core advantages 
1. Excellent mechanical properties: outstanding tensile strength, rigidity, creep resistance, fatigue resistance, wear resistance, self-lubricating, shock absorption and noise reduction, suitable for moving load-bearing parts such as gears and bearings.   
2. Good heat resistance: high melting point, significantly increased thermal deformation temperature of fiberglass reinforced grades, can be used for high-temperature components in automotive engine compartments.   
3. Chemical resistance: resistant to engine oil, fuel, grease, hydrocarbons, weak bases, and most inorganic salt solutions; Not resistant to strong polar solvents such as strong acids, formic acid, phenol, etc.   
4. Good electrical insulation: Excellent insulation performance in dry state, suitable for electronic components such as connectors and coil frames.   
5. Easy to modify: Glass fiber (GF), carbon fiber (CF), mineral fillers, flame retardants, toughening agents, UV resistant agents can be added to derive a large number of specialized grades (glass fiber reinforced PA66, halogen-free flame retardant PA66, toughened and cold resistant PA66, etc.).   
3、 Application Fields 
1. Automotive industry (largest application scenario): engine peripheral components, intake manifold, radiator water chamber, fuel pipeline joints, wire harness connectors, buckles, transmission gears, lightweight replacement of metal parts, oil and high temperature resistance.   
2. Electronic appliances: connectors, terminal sockets, zip ties, switch housings, coil skeletons, flame-retardant grades used for power components.   
3. Mechanical industry: gears, bearings, sliders, pump impellers, wear-resistant bushings, replacing copper and cast iron to reduce noise and costs.   
4. Textile/industrial fibers: high-strength industrial silk, tire cord, conveyor belts, ropes.   
5. Daily use and hardware: zippers, fasteners, tool handles, sports equipment.