Recovery preparation method of waste and old carbon fiber PA6 composite material

Abstract

The invention relates to a recovery preparation method of a waste and old carbon fiber PA6 composite material. The method comprises the following steps of cutting the carbon fiber PA6 composite material into thin sheet blocks with the volume of 1 to 5.5 cm<3>; then, treating the surface of the obtained thin sheet block until carbon fiber is exposed; performing pretreatment on the thin sheet blocksto obtain the pretreated carbon fiber; adding the pretreated carbon fiber into liquid solvents; heating to 50 to 90 DEG C; adding catalysts into the treatment liquid to obtain a treatment solution; finally, adding the treatment solution into a reaction kettle; performing pressure reduction treatment on the treatment solution in the reaction kettle so that the liquid solvent becomes critical fluid; maintaining the condition time of the critical fluid to be 1 to 3 hours; finally obtaining solid, liquid and gas products; in the constant temperature and constant pressure states, discharging liquid and gas; collecting the solid products; then, cleaning and drying the solid products; finally obtaining the carbon fiber. The method has the advantages that no damage can be caused on the surface ofthe carbon fiber in the separation process of the carbon fiber, so that the mechanical property of the carbon fiber is ensured.

Description

technical field [0001] The invention relates to the technical field of materials and chemistry, in particular to a method for recycling and preparing waste carbon fiber PA6 composite materials. Background technique [0002] As a reinforcing fiber for high-strength composite materials, carbon fiber is in increasing demand with the rapid development of aviation and automotive industries. According to data, only aerospace is expected to increase demand by 10% to 17% per year. In recent years, the world's annual demand for carbon fiber is increasing at a rate of 12%. With the extensive application of carbon fiber composite materials, the amount of waste will also increase sharply. At present, the amount of composite material waste in my country has exceeded 2000kt, and it is estimated that the annual increase of composite material waste will exceed 100kt, including carbon fiber composite materials. A large amount of carbon fiber waste produced by various industries has become a...

AI Technical Summary

Problems solved by technology

[0003] The current recycling methods of carbon fiber composite materials mainly include mechanical recycling method and thermal cracking method. There are a lot of residues attached to the surface of the carbon fiber, and the mechanical properties of the fiber are greatly damaged

The pyrolysis method is to degrade the composite material at high temperature to obtain carbon fibers with a clean surface. However, after the carbon fibers are subjected to high temperature treatment, the mechanical properties of the carbon fibers are greatly reduced, which greatly affects the reuse of carbon fibers.