JPH0841241A - Recovery of reinforcing material from composite plastic - Google Patents

Abstract

PURPOSE:To provide a method for recovering a useful reinforcing material (e.g. whisker) contained in a composite plastic in such a manner that deterioration, damage, lowering of physical properties and aggregate formation of the reinforcing material is suppressed and the reinforcing material is recovered in a dispersed state and can be recycled without requiring additional treatment. CONSTITUTION:This recovering method is applied to a composite plastic composed of a ceramics reinforcing material and a resin matrix for embedding the reinforcing material. The recovering method is composed of the first process where the composite plastic resin is subjected to alcohol decomposition, amine decomposition or hydrolysis by reacting with an alcohol, an amine or water, respectively to obtain a liquid decomposed product and the second process where the recovered reinforcing material having a resin residue on it is heated in a temperature range, in which the reinforcing material is free from deterioration nor damage, to decompose and remove the remained resin to obtain the reinforcing material free from the resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recovering a useful reinforcing material contained in a waste product of a composite plastic, and more particularly, a method for recovering a reinforcing material such as a whisker from a waste product of a composite thermosetting plastic in a reusable state. Regarding

[0002]

2. Description of the Related Art Thermosetting plastic composite materials reinforced with single crystal fibers such as whiskers are used for automobile parts, office automation equipment parts, precision equipment parts, home electric appliance parts and the like.
For example, polyurethane embedded with potassium titanate whiskers is used in automobile bumpers.

Most of the used wastes of these composite plastic parts are crushed and then disposed of in landfill, and valuable useful reinforcing materials are also discarded without being reused. Therefore, it is necessary to develop a method for recovering and regenerating these reinforcing materials. In addition to the waste of used composite plastic parts, it is also necessary to recycle composite plastic scraps generated during manufacturing.

As a technique for recovering the reinforcing material from the composite plastic, for example, Japanese Patent Laid-Open No. 2-121806 discloses a reinforcing material (mainly an inorganic material) embedded in the plastic by thermally decomposing the plastic of the composite plastic.
A method of separating and regenerating is disclosed. in this way,
Since it relies on pyrolysis, only the reinforcement that can withstand the pyrolysis temperature can be reused, but the reinforcement that deteriorates due to pyrolysis cannot be recycled.

Japanese Unexamined Patent Publication (Kokai) No. 4-357006 also discloses a method of thermally decomposing a matrix resin and separating and recovering fibers as a reinforcing material from a liquid thermal decomposition product. Since this method also relies on pyrolysis, only reinforcements that can withstand the pyrolysis temperature can be reused, but reinforcements that deteriorate due to pyrolysis cannot be recycled. Japanese Unexamined Patent Publication (Kokai) No. 6-87123 discloses a method of recovering silica by incinerating a thermosetting resin containing silica as an inorganic filler at a temperature of 800 to 1300 ° C. in an oxidizing atmosphere. According to this method, it is possible to prevent the incomplete combustion products of the resin from remaining in the recovered components. However, this method requires higher temperatures, and thus deterioration of the reinforcing material cannot be avoided.

According to the above-mentioned conventional method, the decomposition of the resin requires a high temperature, so that the physical properties of the ceramic reinforcing material are unavoidably deteriorated.

[0007]

DISCLOSURE OF THE INVENTION The present invention is intended to recover useful reinforcing materials, such as whiskers, contained in composite plastics. A method for recovering a reinforcing material with less deterioration, damage and deterioration of physical properties of the reinforcing material, and further strengthening. It is an object of the present invention to provide a method in which a reinforcing material can be recovered in a state where the materials are isolated and dispersed with little aggregation, and the recovered product can be reused as it is.

[0008]

A method for recovering a reinforcing material from a composite plastic according to the present invention is a method of recovering the resin of a composite plastic comprising a ceramic reinforcing material and a resin matrix in which the reinforcing material is embedded, with alcohol, amine and water. The first step of reacting to form a liquid decomposition product by alcohol decomposition, amine decomposition or hydrolysis, and heating the reinforcing material having the resin residue attached thereto under conditions that the reinforcing material is not deteriorated or damaged, and heat the resin residue. The reinforcing material recovery method of the present invention comprises a second step of decomposing and removing to obtain the reinforcing material to which the resin residue is not adhered. The reinforcing material is recovered from the thermoplastic and thermosetting resin. The reinforcing material to be recovered is an inorganic material such as an oxide, a carbide, or a nitride compounded in a resin. In particular, those having high economic value such as whiskers and ceramic fibers are preferable. However, it is not limited to those with high economic value. Also regarding the size and shape of the reinforcement,
There is no particular limitation.

The resin may be either thermoplastic or thermosetting resin. However, it is particularly suitable for thermosetting resins that require thermal decomposition at high temperatures. A typical example is a polyurethane resin that is easily liquefied by chemical decomposition. The composite plastic in which the above-mentioned resin is filled with the reinforcing material includes not only used molded parts but also defective moldings produced when a product is manufactured from a new material or end materials produced by trimming after molding. This waste product may be directly subjected to chemical decomposition,
It may be ground to a predetermined size in advance and then subjected to chemical decomposition.

As the chemical decomposition, alcohol decomposition, amine decomposition and hydrolysis can be applied. Glycolysis is considered to be a type of alcohol degradation, and glycol decomposition is also included in the chemical degradation of the present invention. In this chemical decomposition, alcohol, amine or water is reacted with a resin forming a matrix of the composite plastic, and the resin forming the matrix is decomposed by alcohol, amine and hydrolyzed to form a low molecular weight molecule.

As the decomposing agent, glycol, alcohol, amine and, in some cases, alkaline aqueous solution can be used. For example, glycol includes ethylene glycol, propylene glycol, glycerin and the like, alcohol includes methanol, ethanol, isopropanol and the like, and amine includes liquid substances such as ethanolamine, propylamine and butylamine. An alkali or the like may be added to these liquids as a decomposition catalyst as a hydrolysis catalyst.

The resin which can be chemically decomposed is a resin having a bond such as an ester bond, a urethane bond or a urea bond. Specifically, it is a thermosetting or thermoplastic polyester resin, urethane resin, urea resin or the like. This chemical decomposition is usually completed in a short time at a temperature of 350 ° C. or lower under pressure. It is preferable to use a known catalyst such as alkali or acid for this chemical decomposition. Thereby, the reaction time can be shortened and the reaction temperature can be lowered.

By this chemical decomposition, the resin constituting the matrix is decomposed, and most of the resin becomes liquid as an organic substance having a low molecular weight. The liquid organic matter can be easily separated from the reinforcing material by filtration, centrifugation or the like. The obtained liquid organic matter can be used as a fuel, a monomer raw material, and other additives. The second step is to heat the reinforcing material to which the resin residue is attached within a temperature range where the reinforcing material is not deteriorated or damaged, and thermally decompose and remove the resin residue to obtain a reinforcing material to which the resin residue is not attached. is there. The thermal decomposition of the resin residue is achieved, for example, by heat treatment in a heating furnace under normal pressure at 400 to 550 ° C. for 1 to 30 minutes, which is a relatively mild condition. As a result, the resin residue attached to the surface of the reinforcing material is thermally decomposed and removed as a low-molecular liquid substance or a gaseous substance. The gas and the liquid substance can be reused as fuel for performing the thermal decomposition in the second step.

According to the reinforcing material recovery method of the present invention, for example,
Deterioration of ceramic fibers such as whiskers and glass fibers
It can be collected in a state in which the degree of damage and deterioration of physical properties is small and in a dispersed state without aggregation.

[0015]

In the method for recovering the reinforcing material of the present invention, the resin constituting the matrix of the composite plastic is chemically decomposed at a low temperature in the first step. Therefore, in order to remove the resin component, the thermal decomposition at a high temperature is carried out. No longer needed. Therefore, it is possible to prevent the recovery reinforcing material from being deteriorated or damaged by being given a high-temperature heat history. In the second step, the amount of resin residue attached to the surface of the isolated reinforcement is decomposed, and since it has already been chemically decomposed, it can be easily decomposed by heat treatment at a low temperature. Can be removed. For this reason,
It is possible to collect high-quality reinforcing material with little deterioration, damage, and deterioration of physical properties of the reinforcing material in each process of recovery processing.

Since the resin constituting the matrix of the composite plastic is chemically decomposed into a low molecular weight and liquefied, the reinforcing material is recovered in a state of being embedded in the composite plastic, and the reinforcing material is not aggregated or unevenly distributed. It can be collected in a uniformly dispersed state. Therefore, the recovered reinforcing material can be reused as it is as a reinforcing material. Further, a new reinforcing material can be added to this and used.
Alternatively, it can be diverted as a raw material for any other purpose.

Since the treatment temperature of the present invention is not excessively high and the treatment time is relatively short, workability is good and continuous treatment is also possible, so that a regenerated product of a reinforcing material of a useful material of good quality can be obtained at a low cost. It becomes possible.

[0018]

EXAMPLES The present invention will be specifically described below with reference to examples. In this embodiment, as the composite plastic, polypropylene glycol (PPG), diethyltoluenediamine (DE)
TDA), methylenediphenyl 4,4 isocyanate (MDI) in urethane resin as a monomer raw material, fibrous whiskers of potassium titanate as a reinforcing material (Otsuka Chemical Co., Ltd. “Teismo D”: K ₂ O-8TiO ₂ , Diameter about 0.3μ
m, the length was about 20 μm), and a molded product having a thickness of about 3 mm was used which was filled with the reaction type injection molding machine in a uniform dispersion state.

First, this molded product was hammered for about 5 m.
It was crushed into m squares, and the crushed product was treated as a sample by the following method. (Example 1) 100 g of a sample was placed in an autoclave (manufactured by Nitto High Pressure Co., Ltd., having a capacity of 1000 ml, the same applies hereinafter), and 100 g of ethylene glycol as a decomposing agent was added to the autoclave, followed by sealing. While stirring the contents in an autoclave, the contents were heated to 300 ° C., which had no influence on the whisker crystal structure, and held for 10 minutes. At this time, the maximum pressure in the autoclave was 0.8 MPa.

After cooling, a liquid chemical decomposition product containing whiskers was taken out. This chemical decomposition product was a liquid containing a liquid low molecular weight organic compound containing polyol as a main component, and whiskers as a reinforcing material were dispersed in this liquid. After filtering the liquid containing the liquid organic matter, put the whiskers in the state where the liquid resin residue adheres to the surface,
The liquid organic residue was decomposed and removed by heat treatment at 500 ° C. for 5 minutes under normal pressure.

No residue such as ash or carbide was found on the surface of the recovered whiskers, which confirmed that there was no damage. The whiskers were obtained in a dispersed state without agglomerating. There was no change in the whisker crystal structure. The obtained whiskers could be filled not only with the polyurethane resin as a reinforcing material but also with other resins in the same manner as the new material whiskers, and the physical properties of the recycled products were similar to those of the new materials. . In the case of filling in a polyurethane resin, a flat plate having a thickness of 3 mm is molded by a reaction injection molding machine, and a test piece is prepared from the molded product to obtain physical properties of the molded article, that is, tensile strength, bending strength,
When the low temperature embrittlement temperature was measured, it showed the same physical properties as the polyurethane resin molded product filled with the new whisker material.

Regarding the dispersed state of the whiskers after chemical decomposition, one drop of the decomposition product was dropped on a slide glass with a dropper and observed with a microscope to evaluate the presence or absence of agglomeration of the whiskers. The state of the whiskers recovered after thermal decomposition was observed with a microscope, and the dispersibility of the whiskers was visually evaluated for the presence or absence of agglomeration, the presence or absence of damage on the whisker surface, and the presence or absence of residues, and passed. Was evaluated as ◯, and the failure was evaluated as x, and it was examined whether or not it was in a state of enduring reuse. In addition, the crystal structure of the whiskers was analyzed by an X-ray diffractometer to evaluate whether deterioration (x) or no deterioration (o). The results are summarized in Table 1.

Example 2 100 g of a sample was placed in an autoclave and ethylene glycol 10 was added as a decomposing agent.
After adding 0 g, it was sealed. While stirring the contents in an autoclave, the contents were heated to 300 ° C., which had no influence on the whisker crystal structure, and held for 10 minutes. The maximum pressure in the autoclave at this time was 0.8 MPa. Then, after cooling, a liquid chemical decomposition product containing whiskers was taken out.

As a result of evaluating the dispersion state of the whiskers after the chemical decomposition, it was found that the useful substances, whiskers, were uniformly dispersed in the liquid decomposition product containing the polyol as the main component. After the liquid decomposition product was filtered off, the whiskers with the liquid decomposition product adhering to the surface were placed in a heating furnace and heat-treated at 550 ° C. for 1 minute under normal pressure.

Although the recovered whiskers were obtained in a dispersed state without agglomerating, it was found that some undecomposed portion of the liquid component remained on the surface of the whiskers. There was no change in the whisker crystal structure. The obtained whiskers were filled in a polyurethane resin, and a flat plate having a thickness of 3 mm was molded by a reaction injection molding machine. A test piece was prepared from the whiskers, and the physical properties of the molded product such as tensile strength, bending strength, low temperature embrittlement temperature, etc. When measured, it showed physical properties equivalent to the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Example 3 100 g of a sample was placed in an autoclave, and ethylene glycol 15 as a decomposing agent was added to the autoclave.
After adding 0 g, it was sealed. While stirring the contents in an autoclave, the contents were heated to 300 ° C., which had no influence on the whisker crystal structure, and held for 10 minutes. The maximum pressure in the autoclave at this time was 0.8 MPa. As shown in FIG. 1, immediately without applying the content of the liquid chemical decomposition product containing whiskers, the pressure of 0.8 MPa during the chemical decomposition treatment in the autoclave 1 was immediately changed to the heating furnace 2 under normal pressure. Released to. The liquid decomposition product was decomposed by heating at 500 ° C. for 3 minutes to be gasified and removed. At this time, the contents could easily be atomized and passed through the heating furnace. The reinforcement whiskers were collected in the whisker collector 3 below. As described above, the liquid decomposition products due to the thermal decomposition in the heating furnace can be completely removed in a short time, and a more efficient continuous treatment becomes possible.

No residues such as ash and carbide were found on the surface of the recovered whiskers, confirming that they were not damaged. The whiskers were obtained in a dispersed state without agglomerating. The whisker crystal structure did not change. The obtained whiskers could be filled not only with the polyurethane resin as a reinforcing material but also with other resins in the same manner as the new material whiskers, and the physical properties of the recycled products were similar to those of the new materials. . In the case of filling into a polyurethane resin, a reaction injection molding machine was used to mold a flat plate having a thickness of 3 mm, and a test piece was prepared from the molded product, and the physical properties of the molded product were measured, for example, tensile strength, bending strength, low temperature embrittlement temperature, etc. , Shows the same physical properties as the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Example 4 100 g of a sample was placed in a container equipped with a stirrer, and a solution prepared by mixing 99 g of ethylene glycol with 1 g of caustic soda was added to the container as a decomposing agent. The contents of whiskers were stirred under normal pressure. The crystal structure was heated to 160 ° C., which had no influence on the crystal structure, and held for 60 minutes.

After cooling, a liquid chemical decomposition product containing whiskers was taken out. As a result of evaluating the dispersion state of the whiskers after the chemical decomposition, it was found that the useful substances, whiskers, were uniformly dispersed in the liquid decomposition product containing the polyol as the main component. After the liquid decomposition product was filtered off, the whiskers in which the liquid decomposition product adhered to the surface were placed in a heating furnace, and the decomposition product was decomposed and removed by heat treatment at 500 ° C. for 5 minutes under normal pressure. .

No residue such as ash and carbide was observed on the surface of the recovered whiskers, which confirmed that the whiskers were not damaged. The whiskers were obtained in a dispersed state without agglomerating. There was no change in the whisker crystal structure. The obtained whiskers could be filled not only with the polyurethane resin as a reinforcing material but also with other resins in the same manner as the new material whiskers, and the physical properties of the recycled products were similar to those of the new materials. . In the case of filling into a polyurethane resin, a plate having a thickness of 3 mm was molded by a reaction injection molding machine, and a test piece was prepared from the molded product, and the physical properties of the molded product such as tensile strength, bending strength, low temperature embrittlement temperature, etc. were measured. However, it showed the same physical properties as the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

(Example 5) 100 g of a sample was placed in a container equipped with a stirrer, and a liquid prepared by mixing 99 g of ethylene glycol with 1 g of caustic soda was added to the container as a decomposing agent, and the contents were stirred while stirring under normal pressure. It was heated to 160 ° C., which is a temperature that does not affect the crystal structure of, and held for 60 minutes.

After cooling, a liquid chemical decomposition product containing whiskers was taken out. As a result of evaluating the dispersion state of the whiskers after the chemical decomposition, it was found that the useful substances, whiskers, were uniformly dispersed in the liquid decomposition product containing the polyol as the main component. After the liquid decomposition product was filtered off, the whiskers with the liquid decomposition product adhering to the surface were placed in a heating furnace and heat-treated at 400 ° C. for 30 minutes under normal pressure.

Although the recovered whiskers were obtained in a dispersed state without agglomerating, it was found that some undecomposed portion of the liquid component remained on the surface of the whiskers. There was no change in the whisker crystal structure. The obtained whiskers were filled in a polyurethane resin, and a flat plate having a thickness of 3 mm was molded by a reaction injection molding machine. A test piece was prepared from the whiskers, and the physical properties of the molded product such as tensile strength, bending strength, low temperature embrittlement temperature, etc. When measured, it showed physical properties equivalent to the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Example 6 100 g of a sample was placed in an autoclave, and a liquid obtained by mixing 99 g of methyl alcohol with 1 g of caustic soda was added to the container as a decomposing agent, and then the container was closed. While stirring the contents in an autoclave, the contents are heated to 160 ° C., which does not affect the crystal structure of whiskers, and kept for 30 minutes. The maximum pressure in the autoclave at this time was 2.0 MPa.

After cooling, a liquid chemical decomposition product containing whiskers was taken out. As a result of evaluating the dispersion state of the whiskers after the chemical decomposition, it was found that the useful substances, whiskers, were uniformly dispersed in the liquid decomposition product containing the polyol as the main component. After separating the liquid decomposition products by filtration, put the whiskers with the liquid decomposition products attached to the surface in a heating furnace, and heat-treat at 550 ° C. for 3 minutes under normal pressure to decompose the liquid decomposition products. Removed.

No residue such as ash and carbide was found on the surface of the recovered whiskers, confirming that there was no damage. The whiskers were obtained in a dispersed state without agglomerating. There was no change in the whisker crystal structure. The obtained whiskers could be filled not only with the polyurethane resin as a reinforcing material but also with other resins in the same manner as the new material whiskers, and the physical properties of the recycled products were similar to those of the new materials. . In the case of filling into a polyurethane resin, a reaction injection molding machine is used to mold a flat plate having a thickness of 3 mm, and a test piece is prepared from this to measure the physical properties of the molded product, such as tensile strength, bending strength, low temperature embrittlement temperature, etc. As a result, it showed the same physical properties as the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Example 7 100 g of a sample was placed in an autoclave, and a liquid obtained by mixing 99 g of isopropyl alcohol with 1 g of caustic soda was added as a decomposing agent to the container and then sealed. While stirring the contents in an autoclave, the temperature of the whiskers was not affected at 16 ° C.
Heat to 0 ° C. and hold for 30 minutes. The maximum pressure in the autoclave at this time was 2.0 MPa.

After cooling. A liquid chemical decomposition product containing whiskers was taken out. As a result of evaluating the dispersion state of the whiskers after the chemical decomposition, it was found that the useful substances, whiskers, were uniformly dispersed in the liquid decomposition product containing the polyol as the main component. After separating the liquid decomposition products by filtration, put the whiskers with the liquid decomposition products adhering to the surface in a heating furnace, and heat-treat at 500 ° C. for 10 minutes under normal pressure to decompose the liquid decomposition products. Removed.

No residue such as ash or carbide was observed on the surface of the recovered whiskers, which confirmed that the whiskers were not damaged. The whiskers were obtained in a dispersed state without agglomerating. There was no change in the whisker crystal structure. The obtained whiskers could be filled not only with the polyurethane resin as a reinforcing material but also with other resins in the same manner as the new material whiskers, and the physical properties of the recycled products were similar to those of the new materials. . In the case of filling into a polyurethane resin, a plate having a thickness of 3 mm was molded by a reaction injection molding machine, and a test piece was prepared from the molded product, and the physical properties of the molded product such as tensile strength, bending strength, low temperature embrittlement temperature, etc. were measured. However, it showed the same physical properties as the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Example 8 100 g of a sample was placed in an autoclave, and a liquid obtained by mixing 149 g of isopropyl alcohol with 1 g of caustic soda was added as a decomposing agent to the container and then sealed. While stirring the contents in an autoclave, the temperature of the whiskers was not affected at 16 ° C.
Heat to 0 ° C. and hold for 30 minutes. The maximum pressure in the autoclave at this time was 1.5 MPa.

The content of the liquid chemical decomposition product containing whiskers was not taken out, and as shown in FIG. 1, immediately under pressure of 1.5 MPa during the chemical decomposition treatment in the autoclave 1, in the heating furnace 2. Was released under normal pressure. 50 in heating furnace 2
A liquid decomposition product was decomposed and removed by heating at 0 ° C. for 3 minutes. At this time, the contents could be easily atomized and passed through the heating furnace 2. The product of thermal decomposition can be completely removed from the gas outlet 4 in a short time, and a more efficient continuous process can be performed.

The recovered whiskers fall into a whisker collector provided below the heating furnace 2 and are collected, and no residue such as ash and carbide is observed on the surface of the obtained whiskers, and there is no damage. It was confirmed. The whiskers were obtained in a dispersed state without agglomerating. Furthermore, there was no change in the crystal structure of the whiskers. The obtained whiskers are
As a reinforcing material, not only refilling with a polyurethane resin but also other resins could be performed in the same manner as the new material whisker, and the physical properties of the recycled product were similar to those of the new material. In the case of filling into a polyurethane resin, a flat plate having a thickness of 3 mm was molded by a reaction injection molding machine, and a test piece was prepared from it, and the physical properties of the molded body were measured, for example, tensile strength, bending strength, low temperature embrittlement temperature and the like. , Shows the same physical properties as the original molded product, that is, a polyurethane resin molded product filled with a new whisker material.

Comparative Example 1 100 g of a sample was immediately placed in a heating furnace without being chemically decomposed, and heat-treated at 500 ° C. for 5 minutes under normal pressure. On the surface of the whiskers, resin that was hardly decomposed adhered without separation, and it was impossible to collect the whiskers.

(Comparative Example 2) 100 g of a sample was immediately placed in a heating furnace without being chemically decomposed and heat-treated at 600 ° C. for 30 minutes under normal pressure. The recovered whiskers were in a dispersed state, and no residues such as ash and carbide were found on the surface of the whiskers. As a result of analyzing the whisker crystal structure with an X-ray diffractometer, the structure of K ₂ O-8TiO ₂ was altered to the structure of K ₂ O-6TiO. Suggests whisker deterioration.

Table 1 shows a list of the processing conditions of Examples and Comparative Examples and the state of the recovered whiskers. This example shows that the whisker is superior to the comparative example in terms of separability, damage, residual adhesion, and deterioration.

[0046]

[Table 1] Note: EG is ethylene glycol, MA is methyl alcohol, IPA is isopropyl alcohol

[Brief description of drawings]

FIG. 1 is a schematic diagram of a whisker regeneration and recovery device used in Examples 3 and 8.

Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display area B29B 17/00 ZAB 9350-4F // B29K 75:00 105: 06 105: 26 (72) Inventor Takumi Taniguchi Aichi 1 in 41, Yokota, Nagakute, Nagakute-machi, Aichi Prefecture 1st in Toyota Central Research Laboratory, Inc. (72) Inventor Norio Sato 1 in 41, Yokota, Nagakute-cho, Aichi-gun, Aichi District ) Inventor Shoichi Suzuki 1st 41st Yokomichi, Nagakute-cho, Aichi-gun, Aichi-gun, Toyota Central Research Institute Co., Ltd. (72) Inventor Masao Owaki 1st Toyota-cho, Toyota-shi, Aichi Toyota Motor Co., Ltd. (72) ) Inventor Kanemitsu Kondo 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Co., Ltd. (72) Inventor Naruaki Abe 1 Toyota Town, Toyota City, Aichi Toyota Motor Co., Ltd.

Claims (5)

[Claims] 1. A liquid decomposition product obtained by reacting the resin of a composite plastic comprising a ceramic reinforcing material and a resin matrix in which the reinforcing material is embedded with alcohol, amine, and water by alcohol decomposition, amine decomposition or hydrolysis. The first step, and the reinforcing material to which the resin residue is not attached by heating the reinforcing material to which the resin residue is adhered under conditions that do not deteriorate or damage the reinforcing material and thermally decomposing and removing the resin residue. And a second step, which is a method for recovering a reinforcing material from a composite plastic. 2. The method for recovering a reinforcing material from a composite plastic according to claim 1, wherein after the first step, the liquid decomposition product is separated from the reinforcing material to which the resin residue is attached and then the second step is carried out. 3. The method for recovering a reinforcing material from a composite plastic according to claim 1, wherein the first step is carried out under pressure. 4. The reinforcing material from a composite plastic according to claim 3, wherein the product in a pressurized state obtained in the first step is injected and injected into a high temperature atmosphere under normal pressure to carry out the second step. Recovery method. 5. The method for recovering a reinforcing material from a composite plastic according to claim 1, wherein the resin constituting the matrix of the composite plastic is a polyurethane resin.