Decomposition method

Abstract

To provide a decomposition method that can easily improve a handling property of polyurethane resin as a substance to be decomposed, and does not require much time and effort in a decomposition treatment of polyurethane resin.SOLUTION: There is provided a decomposition method that is configured in that: polyurethane resin 10 bundled in a packaging material 20 or a polyurethane resin 10 contained in a container is heated together with a decomposing agent to chemically decompose the polyurethane resin 10 into a decomposed product 13; and the packaging material 20 or the container is separated from the polyurethane resin 10 and / or the decomposed product 13 by heating.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present disclosure relates to a decomposition process. [Background technology]

[0002] Patent Document 1 discloses a decomposition and recovery method for chemical recycling of polyurethane resin. In this method, polyurethane foam is supplied to a reaction vessel in a reduced volume state. As a volume reduction method, a method of compressing the polyurethane foam while heating it at 100 to 250°C is exemplified.

[0003] Patent Documents 2 and 3 disclose methods for treating urethane foam waste to make it reusable as a resource. However, Patent Documents 2 and 3 do not describe chemical decomposition of polyurethane resin. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 10-310663 [Patent Document 2] Japanese Patent Application Publication No. 11-138539 [Patent Document 3] Japanese Patent Application Publication No. 11-138540 Summary of the Invention [Problem to be solved by the invention]

[0005] The method described in Patent Document 1 has the following problems. Specifically, the method described in Patent Document 1 requires that the polyurethane foam be heated to a high temperature for volume reduction. When the polyurethane foam is reduced in volume immediately before being supplied to a reaction vessel, the polyurethane foam must be transported to the reaction vessel in a bulky state before volume reduction. The method described in Patent Document 1 has the risk that even after volume reduction, the polyurethane foam may regain its volume due to its elasticity. For example, when transporting polyurethane foam in a reduced state, it is necessary to maintain the reduced state by increasing the volume reduction conditions, for example, by lengthening the pressing time or increasing the pressing temperature and pressure.

[0006] The present disclosure has been made in view of the above circumstances, and aims to provide a decomposition method that can easily improve the handleability of polyurethane resin as a decomposition target and that does not require much effort during the decomposition treatment of polyurethane resin. The present disclosure can be realized in the following aspects. [Means for solving the problem]

[0007] A decomposition treatment method for chemically decomposing a polyurethane resin into a decomposition product by heating a polyurethane resin bundled in a packaging material or a polyurethane resin contained in a container together with a decomposing agent, the method comprising: The decomposition method, wherein the packaging material or the container is separated from the polyurethane resin and / or the decomposition products by the heating. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a decomposition method that can easily improve the handleability of polyurethane resin as a decomposition target and that does not require much effort during the decomposition treatment of polyurethane resin. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing an example of a polyurethane resin and a packaging material. [Figure 2]FIG. 2 is a schematic diagram showing an example of polyurethane resin bundled together by a packaging material. [Figure 3] FIG. 10 is a schematic diagram showing a first modified example of polyurethane resin bundled in a packaging material. [Figure 4] FIG. 10 is a schematic diagram showing a second modification of polyurethane resin bundled in a packaging material. [Figure 5] FIG. 10 is a schematic diagram showing a third modified example of polyurethane resin bundled in a packaging material. [Figure 6] FIG. 2 is a diagram schematically illustrating a state before decomposition processing. [Figure 7] FIG. 10 is a diagram schematically illustrating the state after decomposition processing. DETAILED DESCRIPTION OF THE INVENTION

[0010] Here, a preferred example of the present disclosure will be described. [1] A decomposition treatment method for chemically decomposing polyurethane resin into decomposition products by heating polyurethane resin bundled in a packaging material or polyurethane resin contained in a container together with a decomposing agent, comprising: The decomposition method, wherein the packaging material or the container is separated from the polyurethane resin and / or the decomposition products by the heating. [2] The decomposition treatment method according to [1], wherein the packaging material or the container is made of a polyolefin resin. [3] The decomposition method according to [1] or [2], wherein the specific gravity of the material constituting the packaging material or the container is smaller than the specific gravity of the decomposition product. [4] The decomposition method according to any one of [1] to [3], wherein the packaging material is in the form of a film, a bag, a box, or a string.

[0011] The present disclosure will be described in detail below. In this specification, when a numerical range is indicated using "-", it is intended to include both the lower limit and the upper limit unless otherwise specified. For example, the expression "10-20" includes both the lower limit "10" and the upper limit "20". In other words, "10-20" has the same meaning as "10 or more and 20 or less". In addition, in this specification, the upper limit and lower limit of each numerical range can be combined in any way.

[0012] 1. Method for decomposing polyurethane resin 10 In the decomposition method, polyurethane resin 10 bundled in packaging material 20 or polyurethane resin 10 contained in a container is heated together with a decomposing agent to chemically decompose polyurethane resin 10 into decomposition products 13. In the decomposition method, packaging material 20 or the container is separated from polyurethane resin 10 and / or decomposition products 13 by heating.

[0013] (1) Polyurethane resin 10 The polyurethane resin 10 may be a polyurethane foam or a non-foamed polyurethane resin. The polyurethane foam may be any of a flexible polyurethane foam, a semi-rigid polyurethane foam, and a rigid polyurethane foam. The polyurethane foam may be an open-cell polyurethane foam or a closed-cell polyurethane foam. The polyurethane resin 10 may be a pulverized product pulverized to a predetermined size. The polyurethane resin 10 may also be a cut product cut to a predetermined size.

[0014] The polyurethane resin 10 may be, for example, scrap material discarded during the manufacturing process of the polyurethane resin 10 and / or raw material discarded during the manufacturing process of the polyurethane resin 10. Raw material discarded during the manufacturing process of the polyurethane resin 10 may be difficult to handle due to stickiness, etc. The technology of the present disclosure can ensure the ease of handling even for polyurethane resin 10 that is difficult to handle by bundling it in a packaging material 20 or storing it in a container.

[0015] The polyurethane resin 10 may be, for example, a used polyurethane resin 10 that is scheduled to be discarded. The used polyurethane resin 10 may be in an unhygienic state. The technology of the present disclosure makes it difficult to touch the polyurethane resin 10 even when the polyurethane resin 10 is in an unhygienic state by bundling it in a packaging material 20 or storing it in a container, thereby ensuring the safety of workers.

[0016] (2) Packaging material or container The polyurethane resin 10 is bundled together by the packaging material 20. From the viewpoint of reducing the volume, the polyurethane resin 10 is preferably bundled together by the packaging material 20 in a compressed state. In the compressed state of the polyurethane resin 10, the polyurethane resin 10 may be compressed substantially uniformly as a whole, or may be compressed such that the compression rate of the portion in contact with the packaging material 20 is higher than that of the other portions. The polyurethane resin 10 may be accommodated in a container. From the viewpoint of reducing the volume, the polyurethane resin 10 is preferably accommodated in the container in a compressed state. In addition, when the polyurethane resin 10 is in a compressed state, the polyurethane resin 10 is preferably compressed substantially uniformly overall.

[0017] The form of the packaging material 20 is not limited as long as it has the function of bundling the polyurethane resin 10. The packaging material 20 is preferably in the form of a film, a bag, a box, or a string.

[0018] 1 and 2 show examples of a film-like packaging material 20. The film-like packaging material 20 preferably has stretchability (extensibility). The film-like packaging material 20 also preferably has self-adhesive properties. Such a packaging material 20 is also called a stretch film. FIG. 2 shows an example of a state in which polyurethane resin 10 is bundled together using the film-like packaging material 20. This polyurethane resin 10 is wound into a roll, with the film-like packaging material 20 wrapped around the outer periphery. The film-like packaging material 20 is easy to use, as it can easily bundle the polyurethane resin 10 simply by wrapping it around without using an adhesive or the like. Furthermore, the film-like packaging material 20 can cover the entire surface of the polyurethane resin 10, making it suitable for polyurethane resin 10 that is difficult to handle or that is in poor hygienic conditions.

[0019] Variation 1 in FIG. 3 is an example of a bag-shaped packaging material 20. The bag-shaped packaging material 20 contains and bundles the polyurethane resin 10. The bag-shaped packaging material 20 is also an example of a container for containing the polyurethane resin 10. The bag-shaped packaging material 20 may be sealed after containing the polyurethane resin 10. The bag-shaped packaging material 20 is easy to use, as it can easily bundle the polyurethane resin 10 by simply pouring the polyurethane resin 10 into it. Furthermore, the bag-shaped packaging material 20 can cover the entire surface of the polyurethane resin 10, making it suitable for polyurethane resin 10 that is difficult to handle or polyurethane resin 10 that is in poor hygienic conditions. The bag-shaped packaging material 20 can contribute to reducing the amount of material required for the packaging material 20 compared to the box-shaped packaging material 20 described below. The bag-shaped packaging material 20 preferably has a capacity corresponding to the volume of the reaction tank 3 described below, for example. By appropriately selecting the size of the bag-shaped packaging material 20, the polyurethane resin 10 can be packaged in a fixed shape, which makes it easy to improve efficiency, such as by automating the feeding into the reaction vessel 3.

[0020] Variation 2 in FIG. 4 is an example of a box-shaped packaging material 20. The box-shaped packaging material 20 contains the polyurethane resin 10 and organizes the polyurethane resin 10. The box-shaped packaging material 20 is also an example of a container for storing the polyurethane resin 10. The box-shaped packaging material 20 may be sealed after storing the polyurethane resin 10. The box-shaped packaging material 20 is easy to use because it allows the polyurethane resin 10 to be easily organized by simply pouring the polyurethane resin 10 into it. Furthermore, the box-shaped packaging material 20 can cover the entire surface of the polyurethane resin 10, making it suitable for polyurethane resin 10 that is difficult to handle or polyurethane resin 10 that is in poor sanitary conditions. The box-shaped packaging material 20 can stand on its own, making packaging or storage easier than bag-shaped packaging material 20. The box-shaped packaging material 20 preferably has a shape and capacity that correspond to the reaction tank 3 described below, for example. By appropriately selecting the shape and size of the box-shaped packaging material 20, the polyurethane resin 10 can be packaged in a fixed shape, which makes it easy to improve efficiency, such as by automating the feeding into the reaction vessel 3.

[0021] Variation 3 in Fig. 5 is an example of a string-shaped packing material 20. The string-shaped packing material 20 is used to tie together, for example, the polyurethane resin 10. The string-shaped packing material 20 may be made of adhesive tape, a cable tie, or the like. The string-shaped packing material 20 can contribute to reducing the amount of material used for the packing material 20 compared to bag-shaped packing materials 20, box-shaped packing materials 20, and the like.

[0022] The packaging material 20 or the container is preferably made of a polyolefin-based resin because of its low melting point and small specific gravity. The polyolefin-based resin can be selected from the group consisting of homopolymers obtained by polymerizing α-olefins and copolymers containing α-olefins as the main monomer component. Specific examples of α-olefins include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, and 1-decene. Among these, preferred polyolefin-based resins are polyethylene-based resins containing ethylene as the main monomer component and polypropylene-based resins containing propylene as the main monomer component. Here, the term "main monomer component" refers to a monomer component that accounts for 50% by mass or more and 100% by mass or less of the resin. The polyolefin-based resin may be a mixture of two or more of the above homopolymers and copolymers.

[0023] The polyethylene resin is not particularly limited as long as it is a resin containing ethylene as a main monomer component. The polyethylene resin may be linear or branched. Examples of the polyethylene resin include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, and linear very low-density polyethylene.

[0024] The polyethylene resin may be an ethylene homopolymer or a copolymer containing ethylene as the main monomer component and other copolymerizable monomer components. The polyethylene resin may be used alone or in combination with two or more types of copolymerizable monomer components that differ in composition, physical properties, etc.

[0025] The softening point of the polyethylene resin is preferably 60° C. or higher and 120° C. or lower, and more preferably 70° C. or higher and 110° C. or lower, from the viewpoints of strength during packaging or storage of the polyurethane resin 10 and ease of separation due to heat. The softening point is determined from the apex of the heat of fusion peak obtained from a thermogram measured using a differential scanning calorimeter (DSC) by heating about 10 mg of resin from −50° C. to 200° C. at a heating rate of 10° C. / min, holding at 200° C. for 1 minute, cooling to −50° C. at a cooling rate of 10° C. / min, and then heating again to 200° C. at a heating rate of 10° C. / min.

[0026] The melt flow rate (MFR) of the polyethylene resin is not particularly limited. The MFR of the polyethylene resin is, for example, 0.1 g / 10 min or more and 20 g / 10 min or less. The MFR is a value measured in accordance with JIS K7210-1 (2014), and the measurement conditions are 190°C and a load of 2.16 kg.

[0027] The polypropylene-based resin is not particularly limited as long as it is a resin containing propylene as the main monomer component. The polypropylene-based resin may be a propylene homopolymer, or a copolymer containing propylene as the main monomer component and other copolymerizable monomer components. The polypropylene-based resin may be a block copolymer, a random copolymer, or a graft copolymer. The polypropylene-based resin may be used alone, or two or more types of polypropylene-based resins differing in copolymerizable monomer components, their compositions, physical properties, etc. may be used in combination.

[0028] The softening point of the polypropylene resin is preferably 50° C. or higher and 150° C. or lower, more preferably 60° C. or higher and 140° C. or lower, from the viewpoints of strength during packaging or storage of the polyurethane resin 10 and ease of separation due to heat. The softening point is determined from the apex of the heat of fusion peak obtained from a thermogram measured using a differential scanning calorimeter (DSC) by heating about 10 mg of resin from −50° C. to 200° C. at a heating rate of 10° C. / min, holding at 200° C. for 1 minute, cooling to −50° C. at a cooling rate of 10° C. / min, and then heating again to 200° C. at a heating rate of 10° C. / min.

[0029] The melt flow rate (MFR) of the polypropylene resin is not particularly limited. The MFR of the polypropylene resin is, for example, 0.2 g / 10 min or more and 18 g / 10 min or less. The MFR is a value measured in accordance with JIS K7210-1 (2014), and the measurement conditions are 230°C and a load of 2.16 kg.

[0030] The specific gravity of the material constituting the packaging material 20 or the container is preferably smaller than the specific gravity of the decomposition product 13. The specific gravity of the decomposition product 13 is typically greater than 1.000. The specific gravity of the material constituting the packaging material 20 or the container is preferably 1.000 or less, more preferably 0.980 or less, even more preferably 0.965 or less, and particularly preferably 0.940 or less. The lower limit of the specific gravity of the material constituting the packaging material 20 or the container is not particularly limited, and is, for example, 0.880 or more. With this configuration, the packaging material 20 after the packaging of the polyurethane resin 10 is unpacked can be floated in the decomposition product 13, and the packaging material 20 can be suitably separated from the polyurethane resin 10 and / or the decomposition product 13. Similarly, the material of the container after the polyurethane resin 10 has been released can be floated in the decomposition product 13, and the container can be suitably separated from the polyurethane resin 10 and / or the decomposition product 13.

[0031] (3) Decomposition agent The decomposing agent is not particularly limited as long as it chemically decomposes and liquefies urethane bonds, but compounds having a hydroxyl group or amine compounds are preferred from the standpoints of reactivity and cost. Examples of compounds having a hydroxyl group include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, trimethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, polyoxyethylene glycol, polyoxypropylene glycol, glycerin, polyethylene glycol, etc. These compounds having a hydroxyl group can be used alone or in combination of two or more. Examples of amine compounds include ethylenediamine, tetramethylenediamine, hexamethylenediamine, propanediamine, 2-ethylhexylamine, isopropanolamine, 2-(2-aminoethylamino)ethanol, 2-amino-2-hydroxymethyl-1,3-propanediol, ethylaminoethanol, aminobutanol, n-propylamine, di-n-propylamine, 3,3'-diaminodipropylamine, 3,3'-diamino-N-methyldipropylamine, n-amylamine, isobutylamine, methyldiethylamine, monoethanolamine, diethanolamine, triethanolamine, di-2-propanolamine, 2-(2-aminoethoxy)ethanol, cyclohexylamine, piperazine, piperidine, aniline, toluidine, benzylamine, phenylenediamine, tolylenediamine, 4,4'-diphenylmethanediamine, xylylenediamine, pyridine, picoline, and pyrazole. These amine compounds can be used alone or in combination.

[0032] The amount of the decomposing agent added is preferably 5 parts by mass or more and 50 parts by mass or less, and more preferably 10 parts by mass or more and 30 parts by mass or less, relative to 100 parts by mass of the polyurethane resin.

[0033] (4) Cracking catalyst In the decomposition reaction using a decomposition agent, a decomposition catalyst (hereinafter also referred to as "catalyst") can be further added as necessary to increase the reaction rate. The catalyst to be added is preferably one that is used in the production of urethane, and examples thereof include triethylamine, N,N-dimethylcyclohexylamine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropane 1,3-diamine, N,N,N',N'-tetramethylhexane 1,6-diamine, N,N,N',N",N"-pentamethyldiethylenetriamine, N,N,N',N",N"-pentamethyldipropylenetriamine, tetramethylguanidine, triethylenediamine, N,N'-dimethylpiperazine, N,-methyl,N'-(2-dimethylamino)ethylpiperazine, N-methylmorpholine, N-(N',N'-dimethylaminoethyl)-morpholine, 1,2-dimethylimidazole, and hexane. Examples of compounds that can be used include hexamethylenetetramine, dimethylaminoethanol, dimethylaminoethoxyethanol, N,N,N'-trimethylaminoethylethanolamine, N-methyl-N'-(2-hydroxyethyl)-piperazine, N-(2-hydroxyethyl)morpholine, bis(2-dimethylaminoethyl)ether, ethylene glycol bis(3-dimethyl)-aminopropyl ether, diazabicycloundecene, stannous octoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutylindimaleate, dioctyltin mercaptide, dioctyltin thiocarboxylate, lead octylate, potassium acetate, and potassium octylate. The reasons why it is preferable to add a catalyst that is used in the production of polyurethane foam are as follows: First, even if the catalyst remains after the series of decomposition steps, it is unlikely to have an adverse effect when producing (foaming) polyurethane foam using recycled polyol. Second, when producing (foaming) polyurethane foam using recycled polyol, the amount of catalyst added can be reduced.

[0034] The amount of catalyst added is preferably 0.1 parts by mass or more and 5 parts by mass or less relative to 100 parts by mass of the decomposing agent.

[0035] 2. Method for decomposing polyurethane resin 10 bundled in packaging material 20 In one example of the decomposition method, polyurethane resin 10 bundled in packaging material 20 is heated together with a decomposing agent to chemically decompose polyurethane resin 10 into decomposition products 13. In one example of the decomposition method, packaging material 20 is separated from polyurethane resin 10 and / or decomposition products 13 by heating. This will be specifically described below with reference to FIGS. 6 and 7.

[0036] (1) Decomposition device 1 The decomposition treatment method can be carried out by a decomposition apparatus 1 equipped with a reaction tank 3 and a heating unit 5 as shown in Figures 6 and 7. The reaction tank 3 may be equipped with an agitation unit (not shown) for agitating the contents.

[0037] (2) Preparation The decomposition method prepares polyurethane resin 10 bundled in packaging material 20. Polyurethane resin 10 is used for a variety of purposes, and the shapes and sizes of the objects to be processed vary. In this decomposition method, polyurethane resin 10 is preferably deformed and / or compressed to a size that fits into reaction vessel 3. Deformed and / or compressed polyurethane resin 10 attempts to restore its original shape due to its elasticity. In this decomposition method, the shape of deformed and / or compressed polyurethane resin 10 can be suitably maintained by using packaging material 20. When polyurethane resin 10 exists as multiple small pieces, multiple pieces of polyurethane resin 10 may be bundled together. The polyurethane resin 10 may be stored and transported bundled in packaging material 20 before being introduced into reaction vessel 3. For example, raw materials discarded during the manufacturing process may be packaged, stored, and transported to reaction vessel 3. Alternatively, used polyurethane resin 10 may be packaged at the site of use and transported to reaction vessel 3.

[0038] (3) Input In the decomposition treatment method, polyurethane resin 10 bundled in packaging material 20 is directly charged into reaction tank 3. Depending on the capacity of reaction tank 3, only one piece of polyurethane resin 10 bundled in packaging material 20 may be charged, or multiple pieces may be charged simultaneously or sequentially.

[0039] (4) Chemical decomposition In the decomposition treatment method, polyurethane resin 10 bundled in packaging material 20 is heated together with a decomposing agent to chemically decompose polyurethane resin 10 into decomposition product 13. The decomposition treatment temperature (heating temperature) will be described later. As will be described later, polyurethane resin 10 that has been unpacked comes into contact with a decomposing agent in reaction tank 3 and undergoes, for example, amine decomposition or glycol decomposition depending on the type of decomposing agent. Decomposition product 13 of polyurethane resin 10 contains polyol derived from the raw material polyol of polyurethane resin 10, amine components derived from the raw material isocyanate, and the like. Decomposition product 13 of polyurethane resin 10 is usually liquid. The liquid decomposition product 13 flows downward in reaction tank 3 and remains in reaction tank 3 together with the decomposing agent.

[0040] The state of the decomposition product 13 is not particularly limited. The decomposition product 13 may be separated into a phase containing a polyol (hereinafter also referred to as the polyol phase) and a phase containing an amine compound (hereinafter also referred to as the amine phase), or may be in a single phase state in which the polyol phase and the amine phase are not separated. Note that, when the decomposition product 13 is phase-separated, it is preferable that the above-mentioned "specific gravity of the material constituting the packaging material 20 or container" is smaller than the specific gravity of the upper phase (usually the polyol phase) in the decomposition product 13.

[0041] (5) Separation In the decomposition method, the packaging material 20 is separated from the polyurethane resin 10 and / or decomposition products 13 by heating. Specifically, when the packaging material 20 reaches a predetermined temperature or higher, the packaging material 20 melts or softens. Then, the packaging of the polyurethane resin 10 is unpacked, and the packaging material 20 is separated from the polyurethane resin 10 and / or decomposition products 13. Note that the separation of the packaging material 20 from the polyurethane resin 10 and / or decomposition products 13 by heating may be achieved by heating alone, or by heating and other operations such as stirring.

[0042] The heating temperature in the decomposition treatment method may be set to a temperature that is equal to or higher than the temperature at which the polyurethane resin 10 is unpacked and that is suitable for decomposing the polyurethane resin 10, depending on the material, strength, etc. of the packaging material 20. For example, the heating temperature may be set to a temperature that is equal to or higher than the softening point of the material that constitutes the packaging material 20. The heating temperature is not particularly limited, but is preferably 100°C or higher and 250°C or lower, more preferably 150°C or higher and 230°C or lower, and even more preferably 170°C or higher and 215°C or lower.

[0043] The packaging material 20 may aggregate in a molten or softened state during or after the decomposition of the polyurethane resin 10. The reason why the packaging material 20 aggregates is unclear, but is speculated as follows. One reason why the packaging material 20 aggregates is speculated to be due to the difference in specific gravity between the materials constituting the packaging material 20 and the decomposition product 13. That is, due to the difference in specific gravity, the packaging material 20 may gather and aggregate at specific locations, such as the surface of the decomposition product 13. Another reason why the packaging material 20 aggregates is speculated to be due to the difference in polarity between the materials constituting the packaging material 20 and the decomposition product 13. That is, due to the difference in polarity, the materials constituting the packaging material 20 may not mix with the decomposition product 13, causing the packaging material 20 to aggregate together. Additionally, if the packaging material 20 was used to pack the polyurethane resin 10 in an elongated state, the packaging material 20 may have naturally aggregated when the packaging was unpacked.

[0044] When the temperature of the packaging material 20 in the reaction tank 3 drops below a predetermined temperature (for example, 70°C), the melted or softened packaging material 20 solidifies. The solidified packaging material 20 can be easily recovered from the liquid decomposition product 13. If the specific gravity of the material composing the packaging material 20 is smaller than the specific gravity of the decomposition product 13, the packaging material 20 floats on the surface of the liquid decomposition product 13. The decomposition treatment method may involve recovering the packaging material 20 separated from the polyurethane resin 10 and / or the decomposition product 13.

[0045] 3. Method for decomposing polyurethane resin 10 contained in a container Another example of the decomposition method is to heat polyurethane resin 10 contained in a container together with a decomposing agent, thereby chemically decomposing polyurethane resin 10 into decomposition products 13. Another example of the decomposition method is to separate the container from polyurethane resin 10 and / or decomposition products 13 by heating. Note that separating the container from polyurethane resin 10 and / or decomposition products 13 by heating may be achieved by heating alone, or by heating and another operation such as stirring.

[0046] In "3. Decomposition method for polyurethane resin 10 contained in a container," the decomposition device 1, preparation, introduction, and chemical decomposition are applied as is by replacing "polyurethane resin 10 contained in a packaging material 20" in "(1) Decomposition device 1," "(2) Preparation," "(3) Introduction," and "(4) Chemical decomposition" in the above-mentioned "2. Decomposition method for polyurethane resin 10 contained in a packaging material 20" with "polyurethane resin 10 contained in a container," and by replacing other references to "packaging material 20" with "container."

[0047] In this decomposition method, the container is separated from the polyurethane resin 10 and / or decomposition products 13 by heating. Specifically, when the container reaches a predetermined temperature or higher, the container melts or softens. Then, the polyurethane resin 10 comes out of the container, and the container is separated from the polyurethane resin 10 and / or decomposition products 13.

[0048] The heating temperature in the decomposition treatment method may be set according to the material, strength, etc. of the container, at a temperature at or above which the polyurethane resin 10 can come out of the container and that is suitable for decomposing the polyurethane resin 10. For example, the heating temperature may be set at or above the softening point of the material that constitutes the container. The heating temperature is not particularly limited, but is preferably 100°C or higher and 250°C or lower, more preferably 150°C or higher and 230°C or lower, and even more preferably 170°C or higher and 215°C or lower.

[0049] The containers may aggregate in a molten or softened state during or after the decomposition of polyurethane resin 10. The reason why the containers aggregate is not clear, but is speculated as follows. One reason why the containers aggregate is speculated to be due to the difference in specific gravity between the material constituting the containers and decomposition product 13. That is, due to the difference in specific gravity, the containers may gather and aggregate at specific locations, such as the surface of decomposition product 13. Another reason why the containers aggregate is speculated to be due to the difference in polarity between the material constituting the containers and the polarity of decomposition product 13. That is, due to the difference in polarity, it is speculated that the material constituting the containers does not mix with decomposition product 13, causing the containers to gather together.

[0050] When the temperature of the containers in the reaction tank 3 drops below a predetermined temperature (for example, 70°C), the melted or softened containers solidify. The solidified containers can be easily recovered from the liquid decomposition product 13. If the specific gravity of the material constituting the containers is smaller than the specific gravity of the decomposition product 13, the containers will float on the surface of the liquid decomposition product 13. The decomposition treatment method may involve recovering the containers separated from the polyurethane resin 10 and / or the decomposition product 13.

[0051] 4. Effects of this embodiment In this embodiment, the polyurethane resin 10 is charged into the decomposition apparatus 1 while being packed in the packaging material 20 or housed in a container, thereby improving the efficiency of charging the decomposition target material. For example, because the polyurethane resin 10 can be packed or housed in a fixed shape, it is easier to improve efficiency, such as by automating the charging process, compared to charging the polyurethane resin 10 directly into the decomposition apparatus 1. Furthermore, even if the polyurethane resin 10 itself is sticky or difficult to handle, handling becomes easier when the polyurethane resin 10 is packed in the packaging material 20 or housed in a container, improving work efficiency. This embodiment can ensure the safety of workers by reducing the possibility of direct contact with polyurethane resin 10, which is a hygiene concern. For example, polyurethane resin 10 from a used mattress or the like, which is a concern for contamination with pathogens, excrement, etc., can be transported and introduced into decomposition apparatus 1 while remaining sealed in packaging material 20 or a container. In this embodiment, when the polyurethane resin 10 is packed or stored in a compressed state, the amount of polyurethane resin 10 that can be added in one addition operation of adding a predetermined volume of the decomposition target material can be increased, thereby improving the addition efficiency in terms of the volume of the decomposition target material. In this embodiment, when polyurethane resin 10 is packed or stored in a compressed state, the compressed state can be maintained more suitably than when polyurethane resin 10 itself is compressed by heat pressing, for example. Furthermore, polyurethane resin 10 (waste) can be reduced in volume at the location where it is generated and transported to decomposition device 1 without using a large-scale device such as a press. This contributes to reducing the effort and cost of transportation.

[0052] On the other hand, compared to when polyurethane resin 10 itself is compressed by heat pressing, the use of packaging material 20 or a container may require complicated operations such as unpacking polyurethane resin 10 and removing polyurethane resin 10 from the container during decomposition treatment. In this respect, in this embodiment, packaging material 20 or the container is separated from polyurethane resin 10 and / or decomposition products 13 by heating, so complicated operations are not required. In other words, this embodiment does not require much effort even during decomposition treatment. In this embodiment, the packaging material 20 or the container is separated from the polyurethane resin 10 and / or the decomposition product 13, so that components derived from the packaging material 20 or the container are less likely to remain in the obtained decomposition product. Therefore, when the obtained decomposition product is used as a recycled raw material, the purity of the recycled raw material can be improved. In this embodiment, when the packaging material 20 or the container is collected, the collected packaging material 20 or the container can be reused as a recycled material.

[0053] When the packaging material 20 or the container is made of a polyolefin resin, the decomposition temperature of the polyurethane resin 10 can be set to a temperature equal to or higher than the temperature at which the packaging material 20 or the container melts or softens. Therefore, by heating to chemically decompose the polyurethane resin 10, the packaging or container can be suitably released. When the packaging material 20 or the container is made of a polyolefin-based resin, the packaging material 20 or the container can be suitably aggregated during and after the decomposition of the polyurethane resin 10. Then, when the temperature drops below the melting point of the polyolefin-based resin, the packaging material 20 or the container solidifies, making it easy to recover the packaging material 20 or the container.

[0054] If the specific gravity of the material that constitutes the packaging material 20 or the container is smaller than the specific gravity of the decomposition product 13, the packaging material 20 or the container will float on the surface of the decomposition product 13, making it easy to collect. [Example]

[0055] 1. Example 1 (1) Preparation of polyurethane resin bundled in packaging material A polyurethane foam composition (liquid A and liquid B) was prepared in the proportions shown in Table 1, and a polyurethane foam was produced as the decomposable polyurethane resin by slab foaming. The density of the resulting polyurethane foam was measured in accordance with JIS K7222:2005. The measured density is also shown in Table 1.

[0056] The details of each raw material are as follows: Polyol: Polyether polyol, number average molecular weight 3000, functionality 3, hydroxyl value 56.1 mg KOH / g, product name: Sannix GP-3050NS, manufactured by Sanyo Chemical Industries, Ltd. Amine catalyst: Product name: DABCO 33LSI, manufactured by EVONIK Foam stabilizer: Silicone foam stabilizer, product name: L-595, manufactured by Momentive Tin catalyst: Stannous octoate, product name: MRH-110, manufactured by Johoku Chemical Industry Co., Ltd. Foaming agent: Water Isocyanate: Tolylene diisocyanate, product name: Coronate T-80, manufactured by Tosoh Corporation, NCO%: 48.2%

[0057] [Table 1]

[0058] A low-density polyethylene stretch film was prepared as a packaging material. The polyurethane foam was cut into a 20 mm thick sheet. The polyurethane foam was adjusted to a size of 100 g.

[0059] The polyurethane foam was compressed and wound into a roll, and a stretch film was wrapped around the outer periphery. The self-adhesive properties of the stretch film allowed the polyurethane foam to maintain its compressed state without the use of adhesives or the like. In this way, a sample of polyurethane resin bundled in the packaging material of Example 1 was prepared.

[0060] (2) Decomposition of polyurethane resin In a 1 L separable flask, 15 g of 3,3'-diaminodipropylamine was added as a decomposition agent to the sample from Example 1 (100 g of polyurethane resin to be decomposed), and the mixture was heated at 210°C for 5 hours. The stretch film packaging was then unwrapped by the heat, exposing the polyurethane foam from the stretch film. The exposed polyurethane foam was chemically decomposed by the decomposition agent. The stretch film aggregated into balls in the liquid decomposition product. When the decomposition product and stretch film were cooled to room temperature, the stretch film solidified in its aggregated state. The solidified bags were easily recovered from the liquid decomposition product.

[0061] (3) Results of Example 1 In Example 1, handling was easily improved by wrapping the polyurethane foam in a stretch film. Furthermore, in Example 1, the stretch film was separated from the polyurethane foam and / or decomposition products by heating without any special operation during decomposition treatment, which saved time and effort.

[0062] 2. Example 2 (1) Preparation of polyurethane resin bundled in packaging material A low-density polyethylene bag was prepared as a packaging material. 100 g of polyurethane foam was cut out from a polyurethane foam produced in the same manner as in Example 1. The cut polyurethane foam was placed in a bag to prepare a sample of polyurethane resin 10 bundled in a packaging material of Example 2. The sample of Example 2 is also a sample of polyurethane resin placed in a bag as a container.

[0063] (2) Decomposition of polyurethane resin In a 1 L separable flask, 15 g of 3,3'-diaminodipropylamine was added as a decomposition agent to the sample from Example 2 (100 g of polyurethane resin to be decomposed), and the mixture was heated at 210°C for 5 hours. The bag packaging then came undone, and the polyurethane foam came out of the bag. The polyurethane foam that came out of the bag was chemically decomposed by the decomposition agent. The bags aggregated into balls in the liquid decomposition product. When the decomposition product and bags were cooled to room temperature, the bags solidified in an aggregated state. The solidified bags were easily recovered from the liquid decomposition product.

[0064] (3) Results of Example 2 In Example 2, the polyurethane foam was packaged in a bag (enclosed in a bag), which made it easier to handle. Furthermore, in Example 2, the bag was separated from the polyurethane foam and / or decomposition products by heating without any special operation during the decomposition treatment, which saved time and effort.

[0065] The present disclosure is not limited to the above-described embodiments, and various modifications and variations are possible. [Explanation of symbols]

[0066] 1...Disassembly device 3...Reaction tank 5...Heating section 10...Polyurethane resin 13...decomposed product 20...Packing materials

Claims

1. A decomposition treatment method for chemically decomposing a polyurethane resin into a decomposition product by heating a polyurethane resin bundled in a packaging material or a polyurethane resin contained in a container together with a decomposing agent, the method comprising: The decomposition method, wherein the packaging material or the container is separated from the polyurethane resin and / or the decomposition products by the heating.

2. The decomposition treatment method according to claim 1 , wherein the packaging material or the container is made of a polyolefin resin.

3. 3. The decomposition method according to claim 1, wherein a specific gravity of a material constituting the packaging material or the container is smaller than a specific gravity of the decomposed product.

4. 3. The decomposition processing method according to claim 1, wherein the packaging material is in the form of a film, a bag, a box, or a string.

Images