PA66 (Polyamide 66, Nylon 66) is a semi-crystalline general-purpose engineering plastic with superior strength, rigidity, heat resistance, wear resistance and self-lubrication compared with PA6. 

Its basic density range is stable and less affected by crystallinity, and different modified types bring obvious density differences, with minor differences among different grades and modified types, as detailed below:

General-Purpose Neat PA66: 1.13～1.15 g/cm³, typical value 1.14 g/cm³, the most commonly used density standard for basic grades

Glass Fiber Reinforced PA66 (10%～30% Glass Fiber): 1.18～1.42 g/cm³, the higher the glass fiber content, the more significant the density increase, with remarkable improvement of strength and rigidity

Mineral Filled PA66 (Talc / Calcium Carbonate Filled): 1.17～1.32 g/cm³, density is positively correlated with filler loading, focusing on improving dimensional stability and reducing cost

Flame Retardant PA66 (Halogen-Free / Halogenated): 1.15～1.21 g/cm³, halogen-free flame retardant systems have slightly higher density than neat PA66, halogenated systems have relatively larger density increase

Toughened Modified PA66 (Cold Resistant / Impact Type): 1.13～1.17 g/cm³, toughening agent addition causes slight density fluctuation, core improvement of low-temperature toughness and impact resistance

Glass Fiber + Mineral Composite Reinforced PA66: 1.20～1.37 g/cm³, balancing the high strength of glass fiber and dimensional stability of minerals, density between single reinforcement systems

This density parameter is a core basis for the design of high-precision structural parts such as automotive engine peripheral components, electronic and electrical connectors, mechanical gears, bearings and textile accessories. The stable density brought by semi-crystalline structure enables it to maintain good dimensional accuracy under high temperature and high load working conditions. Density calculation is also key data for product weight control, mold design, assembly clearance matching and injection molding parameter setting, while supporting its core properties of high strength, high rigidity, wear resistance and self-lubrication.