Nylon, also known as polyamide (PA), is a general term for thermoplastic resins whose molecular chains contain repeating amide groups [-NHCO]-. This includes aliphatic PA, aliphatic-aromatic PA, and aromatic PA. Among them, aliphatic PA has a wide variety, high production, and extensive applications, with its name determined by the specific number of carbon atoms in the synthetic monomer.

Nylon boasts numerous characteristics, thus finding widespread application in the automotive, electrical equipment, mechanical components, transportation equipment, textile, and paper-making machinery industries. As the miniaturization of vehicles, the high-performance electronic and electrical equipment, and the lightweighting of machinery and equipment accelerate, the demand for nylon will increase significantly. Particularly as a structural material, nylon is subject to stringent requirements regarding its strength, heat resistance, and cold resistance.

Nylon's inherent disadvantages are also significant factors limiting its applications, especially for the two major varieties, PA6 and PA66. Compared to PA46, PAl2, and others, they offer strong price advantages, although some properties may not meet the requirements of certain industries. Therefore, it is necessary to expand its application scope by modifying certain properties for specific fields of use. Due to PA's strong polarity, high moisture absorption, and poor dimensional stability, these issues can be improved through modification.