Technological tendency of polyamide resin's application in modified engineering plastic
——Ding Chao, general manager of nylon production line of Kingfa SCI. & TECH

Mr Ding stated that thin-walled and down-sizing is the development trend of plastic products and the requirement for materials are high fluidity, high hardness and better performance in flame-retardant. During the thinning process, the usage of nylon 66 will increase. Semi-aromatic nylon containing a benzene ring framework, its molecular chain has high rigidity and low water absorption, and its usage will also increase gradually among the thinning process. In the thinning process, owing to its excellent flame retardancy, semi-aromatic will replace a part of nylon 6 and nylon 66 applications in the electrical and electronics industry. Nylon 66 has better rigidity and flame retardancy than nylon 6, so it has more advantage in the thinning trend. 

He also said that polyamide molecular structure design will achieve more functions. The introduction of different amine/acid monomers disrupts the regularity of molecular chain, PA66/6 copolymer is common. Reduce the crystallinity, improve transparency and toughness; Control the melting point, make polyamide with different melting points; Shrinkage control, reduce nylon shrinkage by controlling the crystallinity, and improve dimensional stability; Bring in segment unit with high resistance, make transparent nylon; Bring in segment unit with high resistance, increase the glass transition temperature, and improve the material heat resistance. End group content control will help achieve more functions. Acid-terminated are mainstream products with more stable color and better anti-yellowing properties. Amine-terminated is less common on the market. Compared with the former, it has higher retention rate of thermo-oxidative ageing and better flame retardancy yet is easy to yellowing; Uncapped one is balanced on properties while double capped has better thermo-oxidative stability.