Nylon 6 (Polycaproamide)

Nylon 6 is produced by the polymerization of caprolactam. The monomer is first mixed with water, which opens the lactam ring and gives w-amino acid:

The formed amino acid reacts with itself or with caprolactam at approximately 250–280°C to form the polymer:

Temperature control is important, especially for depolymerization, which is directly proportional to reaction temperature and water content. Figure 1.1 shows the Inventa-Fisher process.

Figure 1.1. The Inventa-Fisher process for producing nylon 6 from caprolactam: (1) Melting station, (2,3) polymerization reactors, (4) extruder, (5) intermediate vessel, (6) extraction column, (7,8) extraction columns, (9) cooling silo.