Method for preparing slices of nylon 6 in high viscidity

Abstract

The invention relates to a method for producing nylon 6 high-viscosity section. A first, to prepare various kinds of assistants, then to proceed materials input and displacing, after the materials are smitten, adding another two assistants and stirring to proceed hydrolysis ring-opening, pressure of boiler is 0.8-1.0 MPa, temp. of the materials is 250-290 deg.C, then to keep polymerization 60-180 minutes in vacuum -0.05-0.09 MPa, finally to static balance 60-120 minutes in pressure 0.2-0.4 MPa to produce nylon 6 high-viscosity section that relative viscosity is more than 5.0. The method is suitable for the nylon 6 high-viscosity section produced by raw materials of quality product caprolactam, substandard product caprolactam and recovered caprolactam.

Description

technical field [0001] The invention relates to a method for producing nylon 6 high-viscosity chips Background technique [0002] In the patent No. ZL00113446.9, a production method of ultra-high viscosity nylon 6 engineering plastics is mentioned. Although this method breaks through the traditional formula and technology, the relative viscosity of the polymer is increased to above 5.0, but because the method uses a single The catalyst makes the polymerization reaction less intense, the polymerization time is longer, and the hydrolysis and ring opening of caprolactam is not thorough enough, resulting in a high content of low molecular weight in the polymer before extraction. Due to the possibility of oxidation during the production process, directly affect the whiteness of slices, [0003] In summary, although the above-mentioned method has improved the relative viscosity of the polymer to more than 5.0, it still has certain defects in the process of hydrolysis and polymeri...

AI Technical Summary

Problems solved by technology

[0002] In the patent No. ZL00113446.9, a production method of ultra-high viscosity nylon 6 engineering plastics is mentioned. Although this method breaks through the traditional formula and technology, the relative viscosity of the polymer is increased to above 5.0, but because the method uses a single The catalyst makes the polymerization reaction less intense, the polymerization time is longer, and the hydrolysis and ring opening of caprolactam is not thorough enough, resulting in a high content of low molecular weight in the polymer before extraction. Due to the possibility of oxidation during the production process, directly affect the whiteness of slices,

[0003] In summary, although the above-mentioned method has improved the relative viscosity of the polymer to more than 5.0, it still has certain defects in the process of hydrolysis and polymerization.