Method for reclaiming carbon fiber reinforced epoxy resin composite material

Abstract

The invention relates to a method for reclaiming a carbon fiber reinforced epoxy resin composite material. The conventional method is high in equipment requirement and high in reclamation cost. The method comprises the following steps of: adding a catalyst into an organic reagent to prepare supercritical CO2 composite solution; putting the carbon fiber reinforced epoxy resin composite material tobe decomposed into a reaction kettle, and adding the supercritical CO2 composite solution; and reacting for 1 to 24 hours at the temperature of between 100 and 250 DEG C under the pressure of 7.5 to 25.0MPa, cooling the product to normal temperature, washing and drying the solid product in the product to obtain carbon fibers, and performing reduced pressure distillation on the liquid product in the product to obtain phenol and derivatives thereof. The catalyst is one or two of liquid super acid, solid super acid, phosphotungstic acid, phosphomolybdic acid, acetic acid, formic acid, hydrochloric acid, sulfuric acid and nitric acid. The method has the advantages of high degradation efficiency, environmental friendliness, low cost and the like, and is a green method for reclaiming the waste and old carbon fiber reinforced epoxy resin composite material.

Description

technical field [0001] The invention belongs to the technical field of polymer recycling, and relates to a method for recycling waste thermosetting composite materials, in particular to a method for recycling carbon fiber-reinforced epoxy resin composite materials by utilizing a supercritical composite liquid. Background technique [0002] Carbon fiber (CF)) / epoxy resin (EP) composite material (referred to as CF / EP composite material) has the characteristics of low density, high specific strength and specific modulus, especially carbon fiber / epoxy resin composite material in the aviation field , automobile industry, sporting goods and other high-tech fields have wide application. With the development of low-carbon economy, the use of carbon fiber / epoxy resin composite materials in various fields has grown rapidly, and has continued to expand to emerging fields such as: new energy, high-speed trains, etc. With the application of carbon fiber / epoxy resin composite materials i...

AI Technical Summary

Problems solved by technology

Traditional methods are difficult to efficiently recycle composite materials: incineration can only recover part of the heat, but some toxic and easily polluting gases are produced during the incineration process; fillers and reinforcing fibers, but require higher reaction temperatures and higher requirements for reaction equipment; fluidized beds (Applied Surface Science 254 (2008) 2588–2593) also require higher temperatures to recover clean carbon fibers ; and the liquid phase cracking method (Polymer Degradation and Stability 89 (2005) 317-326) may pollute the environment and have high recycling costs due to the use of a large amount of organic solvents in the recovery process; due to the low acid resistance of epoxy resin, Using strong corrosive acids such as nitric acid (Journal of Applied Polymer Science, Vol. 95, 1912–1916 (2004)) and formic acid can degrade epoxy resin, and carbon fibers with clean surfaces can be recovered, but strong acids such as nitric acid are Strong, high requirements for reaction equipment, high requirements for operating safety factor, high recovery cost, and difficult post-reaction treatment; supercritical flowing water (Materials and Design 31 (2010) 999–1002), which is considered to have broad prospects ) is clean and pollution-free, but it also needs to be carried out under high temperature and high pressure reaction conditions, and the degraded product is mixed with water, which is not easy to separate; later supercritical alcohol (Ind. Eng. Chem. Res. 2010, 49, 4535–4541) and other fluids have also achieved the degradation of epoxy resin, but it is still in the laboratory stage, and there is still a long way to go before the real industrialization