Properties and injection Molding Technology of PA

PA- polyamide, also known as nylon, is a general term for a large class of amide polymers. The most common ones are PA6, PA66, and PA1010. Recently, with the development of I / T industry, the use of a new type of polyamide-PA46 has increased dramatically, which is used to replace LCP (liquid crystal polymer) to produce plug-ins on computers. Because PA has good mechanical properties, toughness, impact resistance, wear resistance, self-lubrication, flame retardant, insulation and other characteristics, it is widely used in automotive, mechanical, electronic, instrumentation, chemical and other fields, such as gears, pulleys, bearings, impellers, bushings, containers, brushes, zippers and so on. PA6, PA66, PA46 are aliphatic polyamides, are linear polymers, their molecular structure has a very strong polar amide group, so it has a high degree of crystallization ability. The properties of PA products depend on their crystallization morphology and crystallinity. The processing conditions have an effect on the crystal morphology and crystallinity. Different processing conditions, the crystallization change of PA products can reach 40%, the cooling of products is slow, the degree of crystallization is high, and the crystal morphology of larger size is formed. The water absorption also has an effect on the crystallinity. In addition, PA will produce a certain degree of orientation due to flow and shear in the machining process, resulting in the anisotropy of product properties, the strength along the orientation direction is better than that in the non-orientation direction, and the orientation is also beneficial to the crystallization process. This factor should be considered in the die design.