Nylon 6 polymerization method and direct spinning method of melt of polymer obtained with nylon 6 polymerization method

Abstract

The invention relates a nylon 6 polymerization method and a direct spinning method of a melt of a polymer obtained with the nylon 6 polymerization method. A polyamide 6 prepolymer is prepared at the low temperature, the content of oligomers in the melt is controlled in advance, polymerization is completed before a large quantity of cyclic oligomers are generated with a condensation polymerization dynamic strengthening method, a nylon 6 polymer melt with certain molecular weight is acquired, the content of extracts in the product is smaller than or equal to 1.5 wt%, and the content of cyclic dipolymers is smaller than or equal to 0.2wt%; then, direct melt spinning forming is performed after condensation polymerization dynamic strengthening ends. The process is simple, energy consumption is further reduced while the utilization rate of caprolactam is increased, the obtained melt can be directly used for melt spinning, high-capacity large-scale production is easy to realize, a modifier can be added in the polymerization process, flexible production of nylon 6 is realized, and the nylon 6 can be applied to fibers for clothes, industrial filaments, engineering plastics and other fields.

Description

technical field [0001] The invention belongs to the technical field, and relates to a nylon 6 polymerization method and a melt direct spinning method thereof. Background technique [0002] Due to its excellent physical and mechanical properties and textile processing properties, nylon fiber has ranked first in the synthetic fiber family for a long period of time since its inception. However, due to price and production cost constraints and polyester fiber The rapid development of the synthetic fiber is now the second largest output. In 2013, my country's nylon output was 2.1128 million tons, a year-on-year increase of 12.44%, accounting for about 6.3% of the total synthetic fiber output. Nylon fiber has excellent physical properties unmatched by polyester fiber. For example, nylon fiber has high breaking strength, wear resistance ranks first among general textile fibers, good hygroscopicity, excellent elastic recovery rate and fatigue resistance, and good dyeability. Nylon...

AI Technical Summary

Problems solved by technology

In order to ensure that the polymerization process is carried out in a liquid state, the polymerization temperature must be at least 10°C higher than the melting point of polyamide 6. At this time, the polymerization temperature still cannot control the oligomer in the range of direct spinning of the melt, and there is another low-temperature polymerization. Disadvantages, that is, the reaction speed is slow, and the molecular weight of the obtained polymer is low; and the polymerization process at a lower temperature is actually divided into two parts, one is a melt polymerization process, and the other is a solid phase polymerization process. The process is to obtain a polymer with sufficient molecular weight for product development, but there is no effective way to turn the solid polymer formed at low temperature into a suitable spinning method. If fibers are spun from low-temperature polymers, they must be The polymer is melted first, however, at this time, with the balance related to time and temperature, low-molecular compounds are formed, the amount of which is adapted to the temperature of melting, and is always more than that of low-temperature polymerization. In this way, Compared with the normal aggregation method, there is no advantage

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