| abstract |
The invention relates to a nylon 6 polymerization method and its melt direct spinning method. It introduces the method of preparing a polyamide 6 prepolymer at a low temperature, preliminarily controlling the content of the oligomer in the melt, and then strengthening the kinetics by polycondensation reaction in the ring. The polymerization is completed before the oligomer is abundantly produced. Then a nylon 6 polymer melt having a certain molecular weight is obtained. In the obtained product, the extractable content is ≤1.5 wt%, and the cyclic dimer content is ≤0.2 wt % . Then, the fiber is formed directly after the melting and spinning, which is directly after the polycondensation reaction and kinetic strengthening is completed. The invention has simple process, improves the utilization rate of caprolactam, and at the same time it reduces energy consumption, and the obtained melt can be directly used in spinning, so that it is easy for factories to realize mass production. Modifier can be added into the polymerization process to realize nylon 6 flexible production. The product can be applied in the fields of fiber, industrial silk, engineering plastics and so on. |