JP7328019B2 - How to recycle reinforced composites - Google Patents

Description

The present invention relates to a method of reclaiming reinforced composite materials.

Composite reinforcing materials are resins that are base materials, carbon fibers, glass fibers, carbon fibers, glass fibers, metal fibers, organic high-strength fibers, inorganic fillers, metal fillers, carbon nanotubes, and cellulose nanofibers. It is a material molded by compounding reinforcing materials such as Its characteristics are high strength and lightness compared to metals such as iron. Taking advantage of its characteristics, it has begun to be used for windmill blades, etc., in addition to some automobiles and aircraft, as a material that greatly contributes to the improvement of energy efficiency. The production of carbon fiber, one of the reinforcing materials, is expected to more than double in five years from 60,000 tons in 2015 to 140,000 tons in 2020. Carbon fiber is produced by first synthesizing a chemical substance called acrylonitrile from petroleum and making acrylic fiber from it. Then, carbon fibers are produced by carbonizing at a high temperature of several thousand degrees. Carbon fibers are sometimes used as they are, but most are processed into various forms such as continuous fibers, non-woven fabrics, and chopped fibers. It is used as a plastic (CFRP).

Carbon fiber reinforced plastics have excellent material properties such as strength, hardness, rust resistance, and corrosion resistance, but disposal methods are therefore a problem. Common plastics are easily combustible, but carbon fibers are highly graphitized and therefore difficult to burn. Therefore, in Japan, scraps and scraps of carbon fiber reinforced plastics are pulverized as industrial waste and then landfilled. Carbon fibers that are pulverized and disposed of in landfills do not biodegrade and become the cause of marine plastic pollution.

Therefore, a method of separating and recovering the reinforcing material from the composite reinforcing material after use and reusing it has been proposed.
For example, there is a method in which carbon fiber reinforced plastic is treated at a high temperature of 500 to 700° C. in a low-oxygen state to thermally decompose the resin component that is the base material and recover only carbon fibers. A technique called two-step pyrolysis was also developed. The technology involves pyrolyzing the resin component to some degree in the first step, from which combustible gases are recovered. Fuel consumption is reduced by utilizing the gas as combustion gas for heating. Then, in the second stage, the fiber is thermally decomposed again to thermally decompose and remove the resin component remaining on the surface of the fiber (see, for example, Patent Document 1).

A method using superheated steam has also been proposed. Superheated steam is steam having a steam temperature equal to or higher than the saturation temperature at a certain pressure by further superheating saturated steam. In this method, the superheated steam is used to efficiently thermally decompose the resin component of the base material to recover only carbon fibers (see, for example, Patent Document 2).

A method of dissolving a resin component in a specific organic solvent has also been proposed. It is characterized by the low treatment temperature of 100 to 150° C. and the fact that the strength of the recovered carbon fiber does not decrease because it is a wet process and there is no residual resin (for example, see Non-Patent Document 1).

Furthermore, a method has been proposed in which methanol is placed in a high-pressure apparatus of 8 MPa or higher to bring it into a supercritical state and dissolve the resin. This method also uses a relatively low treatment temperature of about 240° C., and is characterized in that the strength of the recovered carbon fibers does not decrease (see, for example, Patent Document 3).

However, most of the practical applications of carbon fiber reinforced plastics are structural materials combined with glass fiber reinforced plastics and metal materials.
For example, hydrogen tanks are molded from carbon fiber reinforced plastic and covered with glass fiber reinforced plastic to improve their shock resistance and scratch resistance, as well as to provide electrical insulation from the outside. there is In addition, although the body of an automobile is usually coated with paint, aluminum paste is often used together with the paint in order to improve the design.
There is a demand for a recycling method for reinforcing materials that can be applied to such structural materials.

Japanese Patent No. 5347056 Japanese Patent No. 5876968 Hitachi Chemical Technical Report No. 42 (2004.1) JP 2013-203826 A

However, the conventionally proposed techniques described above have the following problems.

When the pyrolysis method proposed in Patent Document 1 is applied to a structural material composed of carbon fiber reinforced plastic and glass fiber reinforced plastic, the glass fiber melts and becomes a paste, and the reinforced composite material becomes a reinforcing material. cannot be separated and collected. Moreover, in Patent Document 1, there is a problem of toxicity of thermal decomposition gas of the resin due to thermal decomposition. Epoxy resin, which is the main resin for thermosetting carbon fiber reinforced plastics, generates bisphenol A, which is suspected to be a cancer progenitor, when thermally decomposed, so caution is required. Another problem is that the strength of the recovered carbon fibers is reduced to 70 to 80%. This is because the high temperature treatment causes microcracks on the surface of the carbon fibers. Furthermore, when carbon fibers are composited with resins and processed into carbon fiber reinforced plastics, it is necessary to surface-treat the fibers to increase the affinity with the resins. Carbon fibers recovered by pyrolysis hinder surface treatment due to cracks generated on the surface and residual resin. Therefore, when a carbon fiber reinforced plastic is produced using the carbon fiber recovered by the pyrolysis method, the strength of the carbon fiber itself is lowered, and the strength is further lowered by 70 to 80%.

When the superheated steam method proposed in Patent Document 2 is applied to a structural material made of carbon fiber reinforced plastic and glass fiber reinforced plastic, the glass fibers are melted into a paste like the thermal decomposition method described above. The reinforcing material cannot be separated and recovered from the reinforced composite material. In addition, the strength of the recovered carbon fibers is reduced by high-temperature treatment as in the above-described pyrolysis method. In addition, a rotary kiln is used to improve the efficiency of pyrolysis, but the carbon fiber reinforced plastic to be processed must be pulverized because it needs to be small enough to fit in the device. Therefore, long-fiber carbon fibers cannot be recovered, and in order to recomposite with the base material, when processing the reinforcing material into an intermediate base material, it is limited to some shapes such as non-woven fabrics and fillers. , which limits the applications of reworked reinforced composites.

The normal pressure dissolution method proposed in Non-Patent Document 1 is limited to polyester-based resins such as PET, which limits the types of carbon fiber reinforced plastics that can be processed. Carbon fiber reinforced plastics using thermoplastic resins have a wide variety of resins, including PET (polyester), PP (polypropylene), PEEK (polyetheretherketone), PA (polyamide), and the like. However, it is difficult to distinguish them at a glance. Although it is possible to analyze using a dedicated device, it is not realistic to analyze and sort the collected carbon fiber reinforced plastic parts one by one.

The supercritical method proposed in Patent Document 3 is not practical because the cost of the high-pressure apparatus is very high and it is difficult to increase the size.

As described above, conventionally proposed methods for separating and recovering reinforcing materials from composite reinforcing materials are limited in the types of composite reinforcing materials that can be processed, and the strength of the recovered reinforcing materials decreases and their shape changes due to crushing. Due to a certain method, there are restrictions on the method of compounding and the application of the reinforced composite material when it is reused as a composite reinforced material. In addition, depending on the combination of structural materials to be treated, there may be cases where the reinforcing material cannot be separated and recovered.

The present invention has been made in view of the above problems, and provides a method for regenerating a reinforcing material from a reinforced composite material that can suppress a decrease in the strength of the recovered reinforcing material and maintain the shape of the reinforcing material. intended to provide

As a result of intensive studies to solve the above problems, the present inventors have found that the above objects can be achieved by a method of recovering a reinforcing material from a specific reinforced composite material, and have completed the present invention.

That is, the present invention is as follows.
[1]
a) separating the matrix and reinforcement of the reinforced composite using a treatment solution and/or heat;
b) a step of regenerating the reinforcing material by washing and drying the reinforcing material from which the base material has been removed;
c) processing the recycled reinforcing material into a base material;
d) comprising the step of regenerating a reinforced composite material by combining the obtained base material with the base material;
Repeating the step a) two or more times,
The reinforced composite material used in the step a) is a first reinforced composite material composed of a first type base material and a first type reinforcing material, a second type base material and a second type a second reinforced composite material comprising a reinforcement and a structural material bonded with an adhesive, said reinforcement comprising carbon fibers;
The step a) is
step a) for the first time of separating the first type of matrix and the first type of reinforcement and the second time of separating the second type of matrix and the second type of reinforcement; Perform the step a) of
a1) obtaining a treatment solution containing oxidative active species by electrolyzing sulfuric acid;
a2) immersing the reinforced composite material in the treatment solution to decompose and remove the base material;
A method of reclaiming a reinforced composite material comprising :
[ 2 ]
[ 1 ].
[ 3 ]
The recycled reinforced composite material according to [ 2 ], wherein the reinforcing material contains at least one selected from the group consisting of carbon fibers, glass fibers, and carbon nanotubes, and the recycled reinforcing material has a fiber length of 20 mm or more. how to.
[ 4 ]
The method for regenerating a reinforced composite material according to any one of [1] to [ 3 ], wherein in the step d), the base material is a continuous mixed yarn or a nonwoven fabric.
[ 5 ]
Using the method for regenerating a reinforced composite material according to any one of [1] to [ 4 ], the reinforced composite material before regeneration is at least selected from the group consisting of aircraft, automobiles, spacecraft, ships, and trains. A method for realizing a recycling-oriented society of reinforced composite materials, in which the reinforced composite material used for one transport device and recycled is used again for the transport device.

ADVANTAGE OF THE INVENTION According to this invention, the strength reduction of the recovered reinforcement can be suppressed, and the shape of the reinforcement can be maintained.

1 is a perspective view showing an example of a structural material containing the reinforced composite material of this embodiment; FIG.

EMBODIMENT OF THE INVENTION Hereinafter, the form (henceforth "this embodiment") for implementing this invention is demonstrated in detail. It should be noted that the present invention is not limited to the following description, and various modifications can be made within the scope of the gist of the present invention.

First, the reinforced composite material used in the method for recycling the reinforced material of the present embodiment will be described.

[Reinforced composite material]
The reinforced composite material of the present embodiment is a material whose strength is improved by compounding reinforcing materials such as fibers and fillers, which are different materials, into a base material such as resin. The method of compositing is not particularly limited, and may be a method utilizing interaction such as hydrogen bonding or intermolecular force, and may be dispersed, adhered, adhered, adsorbed, supported, arranged, or the like.
Reinforced composite materials may include matrix materials, reinforcement materials, other additives, and the like.

[Reinforcing material]
The reinforcing material of the present embodiment is a material that is compounded or dispersed in a matrix resin that is a base material of a reinforced composite material, and includes carbon fiber, glass fiber, metal fiber, organic high-strength fiber, and inorganic filler. , carbon nanotubes, cellulose nanofibers, and the like.

Reinforcing materials include fibrous ones and particulate ones, and although the definition is not clear, they generally have a large aspect ratio (length/width) (for example, the aspect ratio is 100 or more, preferably 200 above) are called fibrous, and those with a small aspect ratio (length/width) (for example, the aspect ratio is less than 200, preferably less than 100) are called particulate.

Carbon fiber is a fiber made by carbonizing acrylic fiber or pitch (a by-product of petroleum, coal, coal tar, etc.) as a raw material at a high temperature.
Glass fiber is a fibrous material made by melting and drawing glass.
Metal fibers are made by processing metals such as stainless steel, aluminum, iron, nickel and copper into filaments by plastic working (rolling, etc.), melt spinning, CVD, and the like.
Organic high-strength fibers are fiberized resins such as polyamide, polyester, acryl, polyparaphenylenebenzobisoxazole, and polyimide.

These fibers are processed into intermediate base materials such as continuous fibers and non-woven fabrics and combined with the base material.
A continuous fiber is a long fiber used in the form of a unidirectional layer in which all the fibers are arranged parallel to each other, and can be used by knitting or weaving. Also, by stacking unidirectional layers in various directions, it is possible to create plates with pseudo-isotropy, orthogonality, and anisotropy.
A non-woven fabric is a sheet-like material in which fibers are intertwined without being woven. Non-woven fabric refers to fabric made by bonding or entangling fibers by thermal, mechanical or chemical action.

Elements constituting the inorganic filler include, for example, elements of groups 1 to 16 of the periodic table. Although this element is not particularly limited, an element belonging to groups 2 to 14 of the periodic table is preferable. Specific examples include Group 2 elements (Mg, Ca, Ba, etc.), Group 3 elements (La, Ce, Eu, Ac, Th, etc.), Group 4 elements (Ti, Zr, Hf, etc.), Group 5 elements ( V, Nb, Ta, etc.), Group 6 elements (Cr, Mo, W, etc.), Group 7 elements (Mn, Re, etc.), Group 8 elements (Fe, Ru, Os, etc.), Group 9 elements (Co, Rh, Ir, etc.), Group 10 elements (Ni, Pd, Pt, etc.), Group 11 elements (Cu, Ag, Au, etc.), Group 12 elements (Zn, Cd, etc.), Group 13 elements (Al, Ga, In, etc.), and Group 14 elements (Si, Ge, Sn, Pb, etc.).
Examples of inorganic compounds containing these elements include oxides (including composite oxides), halides (fluorides, chlorides, bromides, iodides), oxoacid salts (nitrates, sulfates, phosphates, boron acid salts, perchlorates, carbonates, etc.), compounds formed from negative elements such as carbon monoxide, carbon dioxide and carbon disulfide and the above elements, and hydrocyanic acid, cyanide, cyanate, thiocyanate Salts such as acid salts and carbides are included.
One inorganic filler may contain one or more of the above elements. A plurality of types of elements may be uniformly present in the particles or unevenly distributed, and the surface of particles of a compound of one element may be coated with a compound of another element. These inorganic fillers may be used alone or in combination.
Preferred inorganic fillers among these are not particularly limited, but for example, the group consisting of silica, zirconia, titanium, zinc, iron, copper, chromium, cadmium, carbon, tungsten, antimony, nickel, and platinum. contains at least one element selected from

A carbon nanotube is a substance in which a six-membered ring network (graphene sheet) made of carbon forms a single-walled or multi-layered coaxial tubular shape. It is an allotrope of carbon and is sometimes classified as a kind of fullerene.

Cellulose nanofibers are tree cellulose fibers that are thinned to a width of about 15 nanometers.

In the present embodiment, the content of the reinforcing material in the reinforced composite material is preferably 10 to 80% by mass based on 100% by mass of the reinforced composite material. Preferably, the lower limit is 15% by mass or more and 20% by mass or more, and preferably the upper limit is 75% by mass or less and 70% by mass or less.

[Base material]
The base material of this embodiment is a resin used as a matrix of a reinforced composite material, and a thermoplastic resin or a thermosetting resin is used.

A thermoplastic resin refers to a resin that can be softened by heating to its glass transition temperature or melting point and can be molded into a desired shape. In general, thermoplastic resins are often difficult to machine, such as cutting and grinding, so injection molding is widely used as the final product after being heated and softened, then pressed into a mold, cooled and solidified. ing. Examples include polyethylene, polypropylene, polystyrene, ABS resin, vinyl chloride resin, methyl methacrylate resin, nylon, fluororesin, polycarbonate, and polyester resin.

A thermosetting resin is a resin that, when heated, polymerizes to form a polymer network structure and hardens and does not return to its original state. In use, a relatively low-molecular-weight resin having fluidity is formed into a predetermined shape, and then cured by heating or the like to cause a reaction. There is a type of adhesive or putty that uses a mixture of component A (base) and component B (curing agent). Thermosetting resins are hard and resistant to heat and solvents. Examples include phenolic resins, epoxy resins, unsaturated polyester resins, polyurethanes, and the like.

In this embodiment, the content of the base material in the reinforced composite material is preferably 20 to 90 parts by mass with respect to 100 parts by mass of the reinforcing material. Preferably, the lower limit is 25 parts by mass or more and 30 parts by mass or more, and preferably the upper limit is 85 parts by mass or less and 80 parts by mass or less.

[Other additives]
Other additives are not particularly limited, and flame retardants, heat stabilizers, antioxidants, light absorbers, release agents, lubricants, various stabilizers, antistatic agents, dyes and pigments, and the above-mentioned composites. Various reactants and the like to be used can be mentioned.
In the present embodiment, the content of other additives in the reinforced composite material may be 0.01% by mass or less and 80% by mass or less when the reinforced composite material is 100% by mass.

[Structural material]
A structural material refers to a material composed of a reinforced composite material including a base material and a reinforcing material, and a different resin material or a different composite reinforcing material adhered thereto. A structural example is shown in FIG.
For example, hydrogen tanks are molded from carbon fiber reinforced plastic and covered with glass fiber reinforced plastic to improve their shock resistance and scratch resistance, as well as to provide electrical insulation from the outside. there is In addition, although the body of an automobile is usually coated with paint, aluminum paste is often used together with the paint in order to improve the design.

(Recycling method of reinforcing material)
The method for regenerating the reinforcing material of the present embodiment may use a treatment solution and/or heat, and preferably uses an electrolytic sulfuric acid method.

The electrolytic sulfuric acid method involves immersing a reinforced composite material consisting of a base material and a reinforcing material in a treatment solution containing oxidative active species obtained by electrolyzing a sulfuric acid solution, thereby removing the base material from water. and carbon dioxide, the decomposition product after decomposition is dissolved in the treatment solution, and then the reinforcing material is taken out from the treatment solution.

The oxidative active species are generated by electrolyzing a sulfuric acid solution at a predetermined current and voltage, and specifically include hydroxyl radicals, peroxosulfuric acid, peroxodisulfuric acid, and the like.

Specifically, the method for recycling the reinforcing material of this embodiment includes:
A) obtaining a treatment solution containing oxidative active species by electrolyzing sulfuric acid;
B) a step of immersing the reinforced composite material, which is scrap material discarded after use or from the manufacturing process, in the treatment solution to decompose and remove the base material;
C) a step of regenerating the reinforcing material by washing and drying the reinforcing material from which the base material has been removed;
including.

A sulfuric acid solution is a solution consisting of sulfuric acid (H ₂ SO ₄ ) and water (H ₂ O). The concentration of sulfuric acid contained in the sulfuric acid solution is preferably 30-95% by weight, more preferably 50-80% by weight. If the concentration of sulfuric acid is less than 30% by weight, the amount of oxidative active species required to decompose the base material of the reinforced composite material cannot be obtained, and it takes a long time to decompose the base material. Even with concentrated sulfuric acid having a concentration of 98% by weight, it is possible to generate oxidative active species if the electrolysis method is devised. This is not preferable because the amount of seeds produced is extremely reduced and the life of electrodes used for electrolysis is extremely shortened.

Concentrated sulfuric acid, hydrochloric acid, or nitric acid may be added to the treatment solution containing the electrolyzed oxidative active species. Peroxides such as hydrogen peroxide and peroxosulfuric acid may also be added to the treatment solution. In this case, the effect of accelerating the decomposition rate of the base material of the reinforced composite material can be obtained.

In the electrolysis of sulfuric acid solutions, platinum electrodes, carbon electrodes, etc. can be used. Electrodes can be used. As the electrolyzer for the sulfuric acid solution, it is preferable to use a diaphragm-type electrolytic cell using a diamond electrode.

The energization conditions for electrolysis are, in the case of a diamond electrode, a current density of 0.01 to 10 A / cm 2 and a voltage of 0.1 to 100 V. etc., as appropriate.

The electrolysis must be performed in a closed system, and is preferably performed while a predetermined amount of sulfuric acid solution is circulated in a closed sulfuric acid solution circulation system. As a circulation method, a method of passing the liquid in parallel to the electrode surface at a flow rate of 50 mL/min or more using a pump or the like, or a method of natural circulation in which convection is caused according to the flow of gas generated by electrolysis may be used.

The treatment time for electrolysis is appropriately changed depending on the amount of sulfuric acid solution, sulfuric acid concentration, flow rate of sulfuric acid solution, current conditions, etc., but it is recommended to treat 1 L of sulfuric acid solution for 0.5 to 10 hours to efficiently remove oxidative active species. It is preferable in terms of generating

In the case of a sulfuric acid electrolysis method in which a sulfuric acid solution is used for the catholyte and the anolyte for electrolysis, sulfuric acid with different concentrations may be used for both electrodes. In particular, in the present invention, a sulfuric acid solution containing oxidative active species obtained by electrolyzing high-concentration sulfuric acid is effective in promoting the decomposition of the base material of the reinforced composite material. It is preferable to increase the concentration and decrease the concentration of sulfuric acid on the cathode side in order to prolong the life of the electrode.

As a power source for electrolyzing the sulfuric acid solution, electricity can be procured from various conceivable devices, but it is preferable to use electricity generated from so-called renewable energy such as solar cells. In addition, hydrogen (generated from the cathode) and oxygen (generated from the anode) generated by electrolysis can be recovered and converted into power generation and heat.

As a method of supplying the obtained sulfuric acid solution containing the oxidizing active species to the treatment tank for decomposing the base material of the reinforced composite material, there is a method of supplying continuously from the electrolytic device to the treatment tank using a pump or the like (continuous method), or a method (batch method) in which a sulfuric acid solution is circulated in a closed system, a processing solution is collected from the system after electrolysis treatment, and the processing solution is supplied to a processing tank. Also, a device capable of heating, cooling, or pressurizing the sampled processing solution may be combined.

In addition, since the processing solution after processing the reinforced composite material can be used repeatedly, it is collected, adjusted in concentration, and reused as a sulfuric acid solution for electrolysis to generate oxidative active species again. can do.

The treatment solution containing oxidative active species is preferably heated to enhance decomposition of the matrix of the reinforced composite material. Although the heating temperature is also related to the boiling point of the treatment solution, it is preferable to use the treatment solution after heating at a temperature of 100° C. or higher in order to efficiently decompose the base material of the reinforced composite material in a short period of time. The heating temperature may be a temperature below the boiling point of the sulfuric acid solution, and heating is performed under atmospheric pressure or an inert gas. It should be noted that the heating of the treatment solution may be carried out under increased pressure or reduced pressure.

(reinforcing material, intermediate base material, reinforced composite material)
In this embodiment, the details of the reinforcing material, the intermediate base material, and the reinforced composite material manufactured using the above-described method for recycling the reinforcing material of the present embodiment will be described below.

In this embodiment, when regenerated by the method for regenerating the reinforcing material of the above-described embodiment, the strength of the regenerated reinforcing material is 80% or more of the strength of the reinforcing material before regeneration, and before and after regenerating the reinforcing material is preferably 90% or more.
Further, in the present embodiment, when the strength of the recycled reinforcing material is 90% or more of the strength of the reinforcing material before being recycled when it is recycled by the method for recycling the reinforcing material of the above-described present embodiment, and the recycling of the reinforcing material It is preferable that the shape retention ratio between the front and back is 80% or more.
The strength of the reinforcing material is measured by the method described in Examples below. The shape retention rate before and after regeneration is measured by the method described in Examples below.

Furthermore, in the present embodiment, when regenerated by the method for regenerating the reinforcing material of the present embodiment described above, the strength of the regenerated reinforcing material is 90% or more of the strength of the reinforcing material before regeneration, and the regenerating of the reinforcing material More preferably, the shape retention rate between the front and back is 90% or more.

In this embodiment, when a fibrous reinforcing material is used, the fiber length of the regenerated reinforcing material is preferably 0.5 μm or more, more preferably 1 μm or more, and still more preferably 10 mm or more. be.

In this embodiment, the intermediate base material may be produced by appropriately processing the reinforcing material recycled by the method for recycling the reinforcing material of the above-described embodiment.
The intermediate substrate of this embodiment may be a continuous fiber or nonwoven comprising recycled reinforcement.

In this embodiment, a recycled reinforced composite material may be produced by compounding the above-described recycled reinforcing material or the above-described intermediate base material in a base material such as a resin.

In this embodiment, when the reinforced composite material is regenerated using the method for regenerating the reinforcement material of the present embodiment described above, the strength of the reinforced composite material regenerated using the regenerated reinforcement material is the same as that before regeneration. It is preferably 65% or more, more preferably 70% or more, still more preferably 75% or more, and preferably 80% or less of the strength of the reinforced composite material made using the reinforcing material. , more preferably 90% or less.
The strength of the reinforced composite material is measured by the method described in Examples below.

(Recycling method of reinforced composite material)
The method for recycling the reinforced composite material of the present embodiment uses the method for recycling the reinforcing material of the above-described embodiment,
a) separating the matrix and reinforcement of the reinforced composite material using a treatment solution and/or heat; b) washing and drying the reinforcement from which the matrix has been removed to regenerate the reinforcement; the process of
c) processing the recycled reinforcing material into a base material;
d) comprising the step of regenerating a reinforced composite material by combining the obtained base material with the base material;
Repeating the step a) two or more times,
The reinforced composite material used in the step a) consists of a reinforced composite material composed of two or more different base materials and/or two or more different reinforcing materials.

In the present embodiment, for example, a first reinforced composite material composed of a first type of base material and a first type of reinforcing material, and a second type of base material and a second type of reinforcing material. When a structural material in which a second reinforced composite material is bonded with an adhesive is subjected to recycling, in the first step a), the first type of base material and the first type of reinforcing material are separated. and, in the second step a), the second kind of base material and the second kind of reinforcing material may be separated, and then the step b) may be performed.

Preferably, the method for recycling a reinforced composite material of this embodiment includes:
The step of a) is
a1) obtaining a treatment solution containing oxidative active species by electrolyzing sulfuric acid;
a2) immersing the reinforced composite material in the treatment solution to decompose and remove the base material;
including.

(Method for realizing a recycling-oriented society of reinforced composite materials)
The method for realizing a recycling-oriented society of reinforced composite materials of this embodiment uses the above-described method for recycling reinforced composite materials of this embodiment,
The reinforced composite material before recycling is used in at least one transportation device selected from the group consisting of aircraft, automobiles, spacecraft, ships, and trains, and the recycled reinforced composite material is used again in the transportation device. good.

EXAMPLES The present invention will be described below with specific examples and comparative examples, but the present invention is not limited to the following examples.

In Examples and Comparative Examples, measurement and evaluation were carried out by the following methods.

<Creation of reinforced composite material>
Reinforcing material: 100 parts by mass of reinforcing material described in each example and comparative example Base material:
·Epoxy resin:
Epicoat 828 (manufactured by Japan Epoxy Resin Co., Ltd.) 20 parts by mass Epicoat 834 (manufactured by Japan Epoxy Resin Co., Ltd.) 20 parts by mass Epicoat 1001 (manufactured by Japan Epoxy Resin Co., Ltd.) 25 parts by mass Epicoat 154 (manufactured by Japan Epoxy Resin Co., Ltd.) 35 Parts by mass Curing agent: DICY7 (manufactured by Japan Epoxy Resin Co., Ltd.) 4 parts by mass Phosphorus compound: Novaled 120 (manufactured by Rin Kagaku Kogyo Co., Ltd.) 3 parts by mass Curing accelerator: Omicure 24 (PII Japan Co., Ltd.) 5 parts by mass Polyvinyl formal: Vinylec K (manufactured by Chisso Corporation) 5 parts by mass

These raw materials were mixed in a kneader according to the procedure shown below to obtain an epoxy resin composition in which polyvinyl formal was uniformly dissolved.
(a) Each epoxy resin raw material and polyvinyl formal are heated to 150 to 190° C. and stirred for 1 to 3 hours to uniformly dissolve the polyvinyl formal.
(b) The resin temperature is lowered to 90° C. to 110° C., a phosphorus compound is added, and the mixture is stirred for 20 to 40 minutes.
(c) Lower the resin temperature to 55 to 65°C, add dicyandiamide and 3-(3,4-dichlorophenyl)-1,1-dimethylurea, knead for 30 to 40 minutes at this temperature, and remove from the kneader. to obtain a resin composition.
(d) The prepared resin composition was applied onto release paper using a reverse roll coater to prepare a resin film. The amount of resin per unit area of the resin film was set to 25 g/m ² .
(e) Next, the reinforcing material is uniformly arranged in a sheet so that the weight of the reinforcing material per unit area is 100 g/m ² , and the resin films are laminated on both sides of the reinforcing material, and the resin is heated and pressed. The composition was impregnated to produce a unidirectional prepreg.

(f) An evaluation sample was prepared by curing the prepreg at 150° C. for 30 minutes.

<Strength ratio of reinforcing material>
The strength of the reinforcing material was measured by the following method.
For the fibrous reinforcing material, the strength in the longitudinal direction was measured using a universal tensile tester (EZ TEST-5N manufactured by Shimadzu Corporation) at 23° C. and a tensile speed of 1.5 mm/min. The strength was the average of 80 arbitrary fibrous reinforcements.
The strength of the particulate reinforcing material was measured using a microcompression tester (MCT-510 manufactured by Shimadzu Corporation) at 23° C. under a load of 1000 mN.
The strength was the average of 50 arbitrary particulate reinforcements.
The strength ratio (%) of the reinforcing material was calculated by the following formula.
Strength ratio of reinforcing material (%) = 100 × (strength of reinforcing material separated and recovered from reinforced composite material / strength of reinforcing material before composite)

<Shape retention rate>
The shape retention rate was calculated by measuring the diameter of the reinforcing material using a scanning probe microscope (SPM-9700 manufactured by Shimadzu Corporation) and calculating the diameter ratio before and after regeneration.
For fibrous reinforcements, the diameter across the width was measured. The diameter was the average of ten arbitrary fibrous reinforcements.
For particulate reinforcements, the average of the major and minor diameters was measured, and the average of the average values for any ten particulate reinforcements was used.
The shape retention rate (%) was calculated by the following formula.
Shape retention rate (%) = 100 × (diameter of reinforcing material separated and recovered from reinforced composite material / diameter of reinforcing material before composite)

[Example 1]
Glass fiber: RS440 RR-520 (manufactured by Nitto Boseki Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The electrolytic sulfuric acid method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, a diamond electrode with an electrode area of 7 cm ² was used, and while the electrode was water-cooled, an aqueous sulfuric acid solution with a concentration of 60% was electrolyzed in a diaphragm-type electrolysis cell to prepare a treatment solution containing oxidative active species. did. The amount of sulfuric acid aqueous solution to be electrolyzed at one time was 100 mL. The current was 0.3-1.0 A/cm ² , the voltage was 17-20 V, and the treatment time was 120 minutes.
200 g of the reinforced composite material was immersed in 500 mL of the treatment solution containing the prepared oxidative active species.
In the first step, the inner reinforced composite material is protected with Teflon (registered trademark) sealing tape, the outer reinforced composite material is immersed at 150 ° C for 5 hours, and the base material of the outer reinforced composite material is decomposed. Reinforcing material A1 was separated and recovered.
After that, in the second step, the sealing tape protecting the inner reinforced composite material is removed, the inner reinforced composite material is immersed at 150 ° C. for 5 hours, and the base material of the inner reinforced composite material is decomposed and reinforced. Material A2 was separated and collected.
The evaluation results of the properties of the separated and recovered reinforcing material A2 are shown in Table 1 below.

[Example 2]
Aramid fiber: Kevlar 29 (manufactured by DuPont-Toray Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The reinforcing material was separated and recovered from the reinforced composite material in the same manner as in Example 1, and the reinforcing material was separated and recovered for evaluation.
The evaluation results of the properties of the separated and recovered reinforcing material A2 are shown in Table 1 below.

[Example 3]
Silica particles: SO-C4 (manufactured by Admatechs Co., Ltd.) were used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The reinforcing material was separated and recovered from the reinforced composite material in the same manner as in Example 1, and the reinforcing material was separated and recovered for evaluation.
The evaluation results of the properties of the separated and recovered reinforcing material A2 are shown in Table 1 below.

[Example 4]
Carbon nanotube: ZEONANO SG1010 (manufactured by Zeon Nanotechnology Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The reinforcing material was separated and recovered from the reinforced composite material in the same manner as in Example 1, and the reinforcing material was separated and recovered for evaluation.
The evaluation results of the properties of the separated and recovered reinforcing material A2 are shown in Table 1 below.

[Example 5]
Cellulose nanofiber: BiNFi-s IMA-1005 (manufactured by Sugino Machine Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The reinforcing material was separated and recovered from the reinforced composite material in the same manner as in Example 1, and the reinforcing material was separated and recovered for evaluation.
The evaluation results of the properties of the separated and recovered reinforcing material A2 are shown in Table 1 below.

[Comparative Example 1]
Glass fiber: RS440 RR-520 (manufactured by Nitto Boseki Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A pyrolysis method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is placed in a combustion furnace, and as the first step, the base material of the external reinforcing composite material is pyrolyzed by processing in a nitrogen atmosphere at 600 ° C. for 5 hours to obtain a reinforcing material. An attempt was made to separate and recover A1, but the glass fibers of reinforcing material A1 melted and became a paste, so it was not possible to proceed to the second step, and it was not possible to separate and recover reinforcing material A2. .

[Comparative Example 2]
Aramid fiber: Kevlar 29 (manufactured by DuPont-Toray Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A pyrolysis method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is placed in a combustion furnace, and as the first step, the base material and reinforcing material A1 of the external reinforced composite material are pyrolyzed by processing in a nitrogen atmosphere at 600 ° C. for 5 hours. did. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered.
Table 2 below shows the evaluation results of the properties of the separated and recovered reinforcing material A2.

[Comparative Example 3]
Silica particles: SO-C4 (manufactured by Admatechs Co., Ltd.) were used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A pyrolysis method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is placed in a combustion furnace, and as the first step, the base material of the external reinforcing composite material is pyrolyzed by processing in a nitrogen atmosphere at 600 ° C. for 5 hours to obtain a reinforcing material. An attempt was made to separate and recover A1, but the silica particles of reinforcing material A1 melted and became a paste, so it was not possible to proceed to the second stage of work, and it was not possible to separate and recover reinforcing material A2. .

[Comparative Example 4]
Carbon nanotube: ZEONANO SG1010 (manufactured by Zeon Nanotechnology Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A pyrolysis method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material was placed in a combustion furnace, and as the first step, the base material of the outer reinforcing composite material was pyrolyzed by treatment at 600° C. for 5 hours in a nitrogen atmosphere. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered. However, the thermal decomposition of the first stage and the second stage could not be separated, and the thermal decomposition of the base material of the outer and inner reinforced composite materials progressed at the same time, so the carbon nanotubes of the reinforcement A1 and the reinforcement A2 of the carbon fiber mixture was recovered, and the reinforcing material A2 could not be separated and recovered.

[Comparative Example 5]
Cellulose nanofiber: BiNFi-s IMA-1005 (manufactured by Sugino Machine Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A pyrolysis method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is placed in a combustion furnace, and as the first step, the base material and reinforcing material A1 of the external reinforced composite material are pyrolyzed by processing in a nitrogen atmosphere at 600 ° C. for 5 hours. did. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered.
Table 2 below shows the evaluation results of the properties of the separated and recovered reinforcing material A2.

[Comparative Example 6]
Glass fiber: RS440 RR-520 (manufactured by Nitto Boseki Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A superheated steam method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is put in a combustion furnace, superheated steam generated using a superheated steam generator UPSS (manufactured by Tokuden Co., Ltd.) is introduced into the combustion furnace, and a nitrogen atmosphere is used as the first stage. At the bottom, an attempt was made to separate and recover the reinforcing material A1 by thermally decomposing the base material of the external reinforcing composite material by treating it at 600 ° C. for 5 hours, but the glass fibers of the reinforcing material A1 melted and became a paste. Since it was closed, it was not possible to proceed to the second stage of work, and it was not possible to separate and recover the reinforcing material A2.

[Comparative Example 7]
Aramid fiber: Kevlar 29 (manufactured by DuPont-Toray Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A superheated steam method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is put in a combustion furnace, superheated steam generated using a superheated steam generator UPSS (manufactured by Tokuden Co., Ltd.) is introduced into the combustion furnace, and a nitrogen atmosphere is used as the first stage. The base material and reinforcement A1 of the outer reinforced composite material were pyrolyzed by treating at 600° C. for 5 hours. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered. Table 2 below shows the evaluation results of the properties of the separated and recovered reinforcing material A2.

[Comparative Example 8]
Silica particles: SO-C4 (manufactured by Admatechs Co., Ltd.) were used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A superheated steam method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is put in a combustion furnace, superheated steam generated using a superheated steam generator UPSS (manufactured by Tokuden Co., Ltd.) is introduced into the combustion furnace, and a nitrogen atmosphere is used as the first stage. At the bottom, an attempt was made to separate and recover the reinforcing material A1 by thermally decomposing the base material of the external reinforcing composite material by treating it at 600 ° C. for 5 hours, but the silica particles of the reinforcing material A1 melted and became a paste. Since it was closed, it was not possible to proceed to the second stage of work, and it was not possible to separate and recover the reinforcing material A2.

[Comparative Example 9]
Carbon nanotube: ZEONANO SG1010 (manufactured by Zeon Nanotechnology Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A superheated steam method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is put in a combustion furnace, superheated steam generated using a superheated steam generator UPSS (manufactured by Tokuden Co., Ltd.) is introduced into the combustion furnace, and a nitrogen atmosphere is used as the first stage. The matrix of the outer reinforced composite material was pyrolyzed by treating it at 600° C. for 5 hours. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered. However, the thermal decomposition of the first stage and the second stage could not be separated, and the thermal decomposition of the base material of the outer and inner reinforced composite materials progressed at the same time, so the carbon nanotubes of the reinforcement A1 and the reinforcement A2 of the carbon fiber mixture was recovered, and the reinforcing material A2 could not be separated and recovered.

[Comparative Example 10]
Cellulose nanofiber: BiNFi-s IMA-1005 (manufactured by Sugino Machine Co., Ltd.) was used as the reinforcing material A1 of the external reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
A superheated steam method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, 200 g of the prepared composite reinforcing material is put in a combustion furnace, superheated steam generated using a superheated steam generator UPSS (manufactured by Tokuden Co., Ltd.) is introduced into the combustion furnace, and a nitrogen atmosphere is used as the first stage. The base material and reinforcement A1 of the outer reinforced composite material were pyrolyzed by treating at 600° C. for 5 hours. After that, as the second step, the base material of the reinforcing composite material inside was thermally decomposed by treatment at 600° C. for 5 hours in a nitrogen atmosphere, and the reinforcing material A2 was separated and recovered.
Table 2 below shows the evaluation results of the properties of the separated and recovered reinforcing material A2.

[Comparative Example 11]
Glass fiber: RS440 RR-520 (manufactured by Nitto Boseki Co., Ltd.) was used as the reinforcing material A1 of the outer reinforced composite material in FIG.
Carbon fiber: Torayca T700SC-12K-50C (manufactured by Toray Industries, Inc.) was used as the reinforcing material A2 of the inner reinforced composite material in FIG.
After preparing the above two reinforced composite materials, a base material to which no reinforcing material was added was laminated as an adhesive layer and cured at 150° C. for 30 minutes to prepare a structural material.
The electrolytic sulfuric acid method was used as a method for separating and recovering the reinforcing material from the reinforced composite material.
Specifically, a diamond electrode with an electrode area of 7 cm ² was used, and while the electrode was water-cooled, an aqueous sulfuric acid solution with a concentration of 60% was electrolyzed in a diaphragm-type electrolysis cell to prepare a treatment solution containing oxidative active species. did. The amount of sulfuric acid aqueous solution to be electrolyzed at one time was 100 mL. The current was 0.3-1.0 A/cm ² , the voltage was 17-20 V, and the treatment time was 120 minutes.
200 g of the reinforced composite material was immersed in 500 mL of the treatment solution containing the prepared oxidative active species. In Comparative Example 11, the reinforcing material was separated and recovered by decomposing the base material of the reinforced composite material at 150° C. for 10 hours without protecting it with a Teflon (registered trademark) sealing tape.
However, since the decomposition of the base material of the outer and inner reinforced composite materials progressed at the same time, a mixture of the glass fiber of the reinforcing material A1 and the carbon fiber of the reinforcing material A2 was recovered, and it was possible to separate and recover the reinforcing material A2. could not.

According to Examples 1 to 5, it can be applied to all combinations of structural materials, can be applied to all types of base materials of reinforced composite materials, does not reduce the strength of the recovered reinforcing material, and is crushed. A method for separating and recovering reinforcements from reinforced composites has been presented that allows the reinforcements to retain their shape because no treatment is required.
In Comparative Examples 1, 5, 7, and 10, the strength of the separated and recovered reinforcing material is greatly reduced, so there are restrictions on the applications that can be used, and it cannot be supplied to reinforced composite materials for transportation equipment that require high reliability. .
In Comparative Examples 2 to 4, 6, 8 to 9, and 11, the reinforcing material A2 could not be separated and recovered.

By using this method, there are no restrictions on the method of compounding or the application of the reinforced composite material when the recovered reinforcing material is reused as a reinforced composite material. It is possible to reprocess waste materials and scraps of reinforced composite materials used for transportation equipment such as spacecraft, ships, and trains into reinforced composite materials for transportation equipment. That is, by supplying a large amount of reinforcing material recovered from a large amount of reinforced composite material to a reinforced composite material for transportation equipment whose usage is increasing, it is possible to circulate without generating surplus reinforcing material. It becomes possible.

Claims (5)

a) separating the matrix and reinforcement of the reinforced composite material using a treatment solution;
b) a step of regenerating the reinforcing material by washing and drying the reinforcing material from which the base material has been removed;
c) processing the recycled reinforcing material into a base material;
d) comprising the step of regenerating a reinforced composite material by combining the obtained base material with the base material;
Repeating the step a) two or more times,
The reinforced composite material used in the step a) is a first reinforced composite material composed of a first type base material and a first type reinforcing material, a second type base material and a second type a second reinforced composite material comprising a reinforcement and an adhesively bonded structural material, said second type of reinforcement comprising carbon fiber;
The step a) is
step a) for the first time of separating the first type of matrix and the first type of reinforcement and the second time of separating the second type of matrix and the second type of reinforcement; Perform the step a) of
a1) obtaining a treatment solution containing oxidative active species by electrolyzing sulfuric acid;
a2) immersing the reinforced composite material in the treatment solution to decompose and remove the base material;
A method of reclaiming a reinforced composite material comprising : The reinforcing material further comprises at least one selected from the group consisting of carbon fibers, glass fibers, metal fibers, organic high-strength fibers, inorganic fillers, metallic fillers, carbon nanotubes, and cellulose nanofibers. A method for regenerating the reinforced composite material according to Item 1 . 3. The recycled reinforced composite material according to claim 2 , wherein the reinforcing material contains at least one selected from the group consisting of carbon fibers, glass fibers, and carbon nanotubes, and the fiber length of the recycled reinforcing material is 20 mm or more. how to. The method of regenerating a reinforced composite material according to any one of claims 1 to 3 , wherein in step d), the base material is a continuous commingled yarn or a non-woven fabric. Using the method for recycling a reinforced composite material according to any one of claims 1 to 4 , the reinforced composite material before recycling is at least selected from the group consisting of aircraft, automobiles, spacecraft, ships, and trains. A method for realizing a recycling-oriented society of reinforced composite materials, in which the reinforced composite material used for one transport device and recycled is used again for the transport device.

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