Method for recycling aramid fiber in aramid fiber phenolic resin composite material

Abstract

The invention provides a method for recovering aramid fiber from an aramid fiber / phenolic resin composite material waste, and belongs to the technical field of aramid fiber recovery methods. The method for recovering the aramid fiber comprises the following steps: putting an aramid fiber / phenolic resin composite material into a mixed recovery solution, and placing the mixed recovery solution in asealed reaction kettle; under the condition that the temperature ranges from 150 DEG C to 200 DEG C, reacting for 6-12 hours in an environment with the gas-phase partial pressure of 2-4 mpa; and washing a reacted product to obtain the recycled aramid fiber. According to the method, phosphoric acid and glacial acetic acid are adopted as a mixed recovery solvent, the degradation capability of the mixed recovery solvent to phenolic resin is improved, great reduction of the performances of the aramid fiber in other recovery solvents and recovery conditions can be avoided, and the aramid fiber is easy to disperse into single fiber in subsequent processing. The method has the advantages that the recovery rate of the aramid fibers is high, the performance loss degree is small, the operation process is simple, and the method is suitable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of aramid fiber recycling methods, and in particular relates to a method for recycling aramid fiber from aramid fiber / phenolic resin composite waste. Background technique [0002] Aramid fiber reinforced phenolic resin composite materials have the characteristics of impact resistance, high specific strength, high specific modulus, excellent heat resistance and corrosion resistance, so they are widely used in aerospace fields, military protection, automobile transportation, wind power generation, Sports equipment, medical equipment and other fields. [0003] There are problems in the disposal of the leftovers generated in the manufacturing stage or the waste materials of aramid fiber reinforced phenolic resin composite materials that have expired in service. At present, aramid fiber-reinforced phenolic resin composite materials are used as solid waste, and are mostly disposed of by incineration, cutting into...

AI Technical Summary

Problems solved by technology

The phenolic resin can be degraded by corrosive strong acid or strong alkali, and aramid fibers can be recovered. However, due to the strong corrosiveness of strong acids and strong alkalis, the requirements for reaction equipment are high, and the performance of aramid fibers will be greatly reduced and lost. The value of reuse, in addition, the separation and reprocessing of degradation products are difficult

The supercritical organic solvent treatment method can obtain relatively pure aramid fibers, but the recovery process requires the use of a large amount of organic solvents and is carried out under high temperature and high pressure reaction conditions, which requires high requirements for reaction equipment and is difficult to achieve industrial applications

[0005] Therefore, there is still a lack of efficient and easy technical means. By degrading the aramid fiber / phenolic resin composite material, the aramid fiber is separated, so as to realize the recycling of the aramid fiber.