Nylon Manufacturing Process

Adipic acid, hexamethylene diamine, and water are added to a reaction vessel to form Hexamethylene diammonium adipate, common known as “nylon salt” solution. After  evaporation, water continues to be  removed from the “salt solution”.  A slurry of TIO2 pigments and water, used to deluster fibers, is added to the nylon salt. Polymerization begins in the reactor where polyhexamethylene adipamide, (Nylon 66), is formed. The nylon polymer is then extruded through spinnerets or pelletized. 

Contamination in:  

• Raw materials

• Adipic acid  

• Hexamethylene diamine

• DI water

• TIO2 pigment slurry  

• Nylon salt solution  

Problems of Contamination

• Fiber breakage, disruptions in fiber spinning 

• Plugging of polymer melt filters

• Plugging of screen packs  

• Change out costs   

• Lost production

• Processing problems at the end-user

• Poor quality, “out-of-spec”, nylon 66 pellets 

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