Resin composition, molded body, method for producing resin composition pellets, method for producing resin composition, method for decomposing and recovering resin composition, and method for producing recycled material

Abstract

Provided are: a resin composition with which it is possible to obtain a molded body having good transparency and comparatively excellent chipping resistance; a molded body; a method for producing resin composition pellets; a method for producing a resin composition; a method for decomposing and recovering a resin composition; and a method for producing a recycled material.

Description

Resin composition, molded body, method for producing resin composition pellets, method for producing resin composition, method for decomposing and recovering resin composition, and method for producing recycled material

[0001] The present invention relates to a resin composition, a molded article, a method for producing resin composition pellets, a method for producing a resin composition, a method for decomposing and recovering a resin composition, and a method for producing a recycled material.

[0002] High transparency is required for vehicle exterior materials such as vehicle lamp covers. In particular, in recent years, with the emergence of vehicle lamps with built-in sensors, vehicle lamp covers and the like that can exhibit even greater transparency are required.

[0003] Due to its high transparency, acrylic resins have been studied for use as exterior materials for vehicles. For example, Patent Document 1 discloses an acrylic resin composition containing a commonly used acrylic resin and polyethylene glycol having a molecular weight of 2,000 to 5,000.

[0004] JP 2019-81850 A

[0005] Incidentally, vehicle exterior materials such as vehicle lamp covers are required to have excellent chipping resistance because they may be scratched or scratched by chipping caused by flying stones, etc. However, the molded article containing the acrylic resin composition described in Patent Document 1 has a problem of poor chipping resistance. Note that excellent transparency and chipping resistance may also be required for applications other than vehicle exterior materials.

[0006] The present invention has been made in consideration of the above circumstances, and aims to provide a resin composition, a molded body, a method for producing resin composition pellets, a method for producing a resin composition, a method for decomposing and recovering a resin composition, and a method for producing recycled materials, which are capable of producing molded bodies that have good transparency and relatively excellent chipping resistance.

[0007] The resin composition according to the present invention is a resin composition containing a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 75 parts by mass or more and less than 95 parts by mass relative to 100 parts by mass of the resin composition, the content of the polyethylene oxide (B) is more than 5 parts by mass and 25 parts by mass or less relative to 100 parts by mass of the resin composition, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η ０ ) / (cη ０ )...(1) (In the formula, η ０ represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B).

[0008] The resin composition according to the present invention is a resin composition comprising a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 95 parts by mass or more and less than 97.5 parts by mass per 100 parts by mass of the resin composition, and the content of the polyethylene oxide (B) is more than 2.5 parts by mass and not more than 5 parts by mass per 100 parts by mass of the resin composition, the (meth)acrylic resin (A) is a methacrylic copolymer comprising: a monomer unit derived from an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms; and a monomer unit derived from methacrylic acid, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η ０ ) / (cη ０ )...(1) (In the formula, η ０represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B).

[0009] The molded article according to the present invention contains the above-described resin composition.

[0010] The method for producing resin composition pellets according to the present invention includes a pelletizing step in which the above-mentioned resin composition is extruded by an extruder to obtain resin composition pellets.

[0011] The method for producing a resin composition according to the present invention is a method for producing the above-mentioned resin composition, comprising a kneading step of melt-kneading the (meth)acrylic resin (A) and the polyethylene oxide (B) in an extruder, wherein the extruder is equipped with a cylinder, and the heater setting temperature of the cylinder located closest to a portion for feeding the polyethylene oxide (B) and downstream of said portion is 110°C or higher and 150°C or lower.

[0012] The method for decomposing and recovering a resin composition according to the present invention includes: a decomposition step of decomposing the above-mentioned resin composition at a temperature of 380°C or higher; a separation step of separating volatile components and solid matter generated by the decomposition step; and a recovery step of recovering a (meth)acrylic acid ester from the volatile components.

[0013] The method for producing recycled material according to the present invention includes a step of melting and kneading a raw material containing crushed material obtained by crushing the above-mentioned molded body, and the content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less per 100 parts by mass of the raw material.

[0014] According to the present invention, there are provided a resin composition, a molded body, a method for producing resin composition pellets, a method for producing a resin composition, a method for decomposing and recovering a resin composition, and a method for producing recycled materials, which are capable of producing molded bodies having good transparency and relatively excellent chipping resistance.

[0015] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[0016] [Resin Composition] <First Invention> Hereinafter, an embodiment of the resin composition according to the first invention (hereinafter referred to as the first embodiment) will be described.

[0017] The resin composition according to the first embodiment contains a (meth)acrylic resin (A) and a polyethylene oxide (B), and the content of the (meth)acrylic resin (A) is 75 parts by mass or more and less than 95 parts by mass per 100 parts by mass of the resin composition, and the content of the polyethylene oxide (B) is more than 5 parts by mass and 25 parts by mass or less per 100 parts by mass of the resin composition.

[0018] The (meth)acrylic resin (A) contains a (meth)acrylic polymer. Examples of the (meth)acrylic polymer include an acrylic polymer containing a monomer unit derived from an acrylic acid derivative such as acrylic acid or an acrylic acid ester, a methacrylic polymer containing a monomer unit derived from a methacrylic acid derivative such as methacrylic acid or a methacrylic acid ester, an acrylic copolymer containing a monomer unit derived from acrylic acid or an acrylic acid derivative, and a methacrylic copolymer containing a monomer unit derived from methacrylic acid or a methacrylic acid derivative. The acrylic copolymer and the methacrylic copolymer may each be a copolymer of acrylic acid or an acrylic acid derivative and methacrylic acid or a methacrylic acid derivative.

[0019] The (meth)acrylic polymer contains more than 50% by mass of monomer units derived from an alkyl (meth)acrylate having an alkyl group having 1 to 4 carbon atoms, and may be a (meth)acrylic homopolymer or a (meth)acrylic copolymer containing more than 50% by mass of monomer units derived from an alkyl (meth)acrylate having an alkyl group having 1 to 4 carbon atoms. The (meth)acrylic resin (A) may contain one type of (meth)acrylic polymer alone, or may contain a mixture of two or more types of (meth)acrylic polymers.

[0020] In one embodiment, the (meth)acrylic resin (A) comprises a methacrylic copolymer containing monomer units derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms and monomer units derived from a vinyl monomer copolymerizable with the monomer derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms. Note that the vinyl monomer is a different monomer from the monomer derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms.

[0021] The content of the alkyl methacrylate-derived monomer units relative to the total mass of the methacrylic copolymer is preferably 85.0% by mass or more and less than 100% by mass, more preferably 90.0% by mass or more and 99.5% by mass or less, and even more preferably 92.0% by mass or more and 99.0% by mass or less. The content of the vinyl monomer-derived monomer units relative to the total mass of the methacrylic copolymer is preferably more than 0% by mass and 15.0% by mass or less, more preferably 0.5% by mass or more and 10.0% by mass or less, and even more preferably 1.0% by mass or more and 8.0% by mass or less.

[0022] The above-mentioned "alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms" means a methacrylate having a C ２ =CH(CH ３ )COOR (R is an alkyl group having 1 to 4 carbon atoms). The vinyl monomer copolymerizable with a monomer unit derived from an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms is a monomer that is copolymerizable with an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms and has a vinyl group.

[0023] Examples of alkyl methacrylates having an alkyl group having 1 to 4 carbon atoms include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, sec-butyl methacrylate, isobutyl methacrylate, etc. The alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms is preferably methyl methacrylate.

[0024] Examples of vinyl monomers copolymerizable with monomer units derived from alkyl methacrylates having an alkyl group of 1 to 4 carbon atoms include (meth)acrylic acids such as acrylic acid and methacrylic acid; (meth)acrylic acid esters (excluding alkyl methacrylates having an alkyl group of 1 to 4 carbon atoms) such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and monoglycerol (meth)acrylate; nitrogen-containing monomers such as (meth)acrylamide, (meth)acrylonitrile, diacetone acrylamide, and dimethylaminoethyl (meth)acrylate; epoxy group-containing monomers such as allyl glycidyl ether and glycidyl (meth)acrylate; styrene-based monomers such as styrene and α-methylstyrene; and other monomers such as maleic acid, itaconic acid, maleic anhydride, and itaconic anhydride. The vinyl monomer is preferably methyl acrylate, ethyl acrylate, or methacrylic acid, and more preferably methyl acrylate or methacrylic acid.

[0025] The (meth)acrylic polymer can be obtained by polymerizing a monomer derived from an alkyl (meth)acrylate having an alkyl group with 1 to 4 carbon atoms and, if necessary, a vinyl monomer copolymerizable with the monomer derived from an alkyl (meth)acrylate having an alkyl group with 1 to 4 carbon atoms, by a method such as bulk polymerization, solution polymerization, suspension polymerization, or emulsion polymerization.

[0026] The stereoregularity of the (meth)acrylic polymer is not particularly limited. The (meth)acrylic polymer may be, for example, an atactic (meth)acrylic polymer, a syndiotactic (meth)acrylic polymer, or an isotactic (meth)acrylic polymer. From the viewpoint of improving heat resistance, the (meth)acrylic polymer is preferably a syndiotactic (meth)acrylic polymer.

[0027] In the syndiotactic (meth)acrylic polymer, the proportion of triads (also referred to as triads) composed of three monomer units that are syndiotactic (also referred to as rr) (hereinafter referred to as "syndiotacticity") is preferably 60% or more, more preferably 70% or more, and even more preferably 80% or more. In the syndiotactic (meth)acrylic polymer, the syndiotacticity may be 100% or less.

[0028] The polymerization for obtaining the (meth)acrylic polymer may be carried out in the presence of, for example, a radical initiator. The radical initiator is not particularly limited, but examples thereof include azo compounds such as azobisisobutyronitrile, azobisdimethylvaleronitrile, azobiscyclohexanenitrile, 1,1'-azobis(1-acetoxy-1-phenylethane), dimethyl 2,2'-azobisisobutyrate, and 4,4'-azobis-4-cyanovaleric acid;Benzoyl peroxide, lauroyl peroxide, acetyl peroxide, caprylyl peroxide, 2,4-dichlorobenzoyl peroxide, isobutyl peroxide, acetylcyclohexylsulfonyl peroxide, tert-butyl peroxypivalate, tert-butyl peroxyneodecanoate, tert-butyl peroxyneoheptanoate, tert-butylperoxy-2-ethylhexanoate, 1,1-di(tert-butyl peroxy) peroxy)cyclohexane, 1,1-di(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, diisopropyl peroxydicarbonate, diisobutyl peroxydicarbonate, di-sec-butyl peroxydicarbonate, di-n-butyl peroxydicarbonate, bis(2-ethylhexyl)peroxydicarbonate, bis(4-tert-butylcyclo hexyl) peroxydicarbonate, tert-amylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxy-ethylhexanoate, 1,1,2-trimethylpropylperoxy-2-ethylhexanoate, tert-butylperoxyisopropyl monocarbonate, tert-amylperoxyisopropyl monocarbonate, tert-butylperoxy-2-ethylhexyl carbonate, tert-butylperoxyallyl carbonate Examples of organic peroxides include peroxyisopropyl carbonate, tert-butylperoxyisopropyl carbonate, 1,1,3,3-tetramethylbutylperoxyisopropyl monocarbonate, 1,1,2-trimethylpropylperoxyisopropyl monocarbonate, 1,1,3,3-tetramethylbutylperoxyisonononaate, 1,1,2-trimethylpropylperoxyisonononaate, and tert-butylperoxybenzoate, as well as combinations of any two or more of these.

[0029] The polymerization for obtaining the (meth)acrylic polymer may be carried out in the presence of a chain transfer agent, if necessary. The chain transfer agent is not particularly limited, but may be an alkyl mercaptan such as n-propyl mercaptan, isopropyl mercaptan, n-butyl mercaptan, tert-butyl mercaptan, n-hexyl mercaptan, n-octyl mercaptan, 2-ethylhexyl mercaptan, n-dodecyl mercaptan, or tert-dodecyl mercaptan; an aromatic mercaptan such as phenyl mercaptan or thiocresol; a mercaptan having 18 or less carbon atoms such as ethylene thioglycol; an ethylene ... Examples of the hydroxyl group-esterifying agent include polyhydric alcohols such as ethylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, and sorbitol; compounds in which a hydroxyl group is esterified with thioglycolic acid or 3-mercaptopropionic acid, 1,4-dihydronaphthalene, 1,4,5,8-tetrahydronaphthalene, β-terpinene, terpinolene, 1,4-cyclohexadiene, hydrogen sulfide, and any combination of two or more thereof.

[0030] The (meth)acrylic resin (A) is a methacrylic copolymer containing a monomer unit derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms and a monomer unit derived from a vinyl monomer copolymerizable with the monomer derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms, thereby making it possible to prevent thermal decomposition of the resin composition according to the first embodiment when the resin composition is extruded using an extruder.

[0031] The content of the (meth)acrylic resin (A) is 75 parts by mass or more and less than 95 parts by mass, preferably 76 parts by mass or more and 93 parts by mass or less, and more preferably 80 parts by mass or more and 90 parts by mass or less, relative to 100 parts by mass of the resin composition. When two or more types of (meth)acrylic resins (A) are contained, the content is the total content of the (meth)acrylic resins (A).

[0032] Polyethylene oxide (B) is a polymer of ethylene oxide. In this specification, polyethylene oxide (B) has the same chemical structure as polyethylene glycol and is therefore used synonymously with polyethylene glycol.

[0033] The reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more, preferably 2.50 dL / g or more, and more preferably 2.70 dL / g or more, from the viewpoint of improving chipping resistance. The reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 25.00 dL / g or less, preferably 20.00 dL / g or less, and more preferably 18.00 dL / g or less, from the viewpoint of obtaining high transparency. The reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less, and in one embodiment, preferably 2.50 dL / g or more and 20.00 dL / g or less, and more preferably 2.70 dL / g or more and 18.00 dL / g or less.

[0034] I = (η - η ０ ) / (cη ０ ) ... (1)

[0035] In the formula (1), η ０ represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B).

[0036] The reduced viscosity (I) of the polyethylene oxide (B) represented by the formula (1) can be made small by reducing the content of ethylene oxide, for example, when the polyethylene oxide (B) is polymerized by reacting ethylene oxide with ethylene glycol using an alcoholate of an alkali metal or the like as a catalyst.

[0037] The content of the polyethylene oxide (B) is more than 5 parts by mass and not more than 25 parts by mass, preferably not less than 7 parts by mass and not more than 24 parts by mass, and more preferably not less than 10 parts by mass and not more than 20 parts by mass, relative to 100 parts by mass of the resin composition.

[0038] The resin composition according to the first embodiment may contain, as necessary, other polymers, additives, etc. in addition to the (meth)acrylic resin (A) and polyethylene oxide (B). Examples of other polymers include high-density polyethylene, fossil fuel-derived linear low-density polyethylene, fossil fuel-derived high-pressure low-density polyethylene, polypropylene resin, elastomer, etc. Examples of additives include antioxidants, ultraviolet absorbers, anti-blocking agents, lubricants, antistatic agents, dispersants, processability improvers, flame retardants, etc.

[0039] <Second Invention> Hereinafter, an embodiment of a resin composition according to a second invention (hereinafter referred to as a second embodiment) will be described. In the description of the second embodiment, only the parts different from the first embodiment will be described.

[0040] The resin composition according to the second embodiment contains a (meth)acrylic resin (A) and a polyethylene oxide (B), and the content of the (meth)acrylic resin (A) is 95 parts by mass or more and less than 97.5 parts by mass per 100 parts by mass of the resin composition, and the content of the polyethylene oxide (B) is more than 2.5 parts by mass and 5 parts by mass or less per 100 parts by mass of the resin composition.

[0041] The (meth)acrylic resin (A) is a methacrylic copolymer containing monomer units derived from alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms and monomer units derived from methacrylic acid.

[0042] The content of the alkyl methacrylate-derived monomer units relative to the total mass of the methacrylic copolymer is preferably 85.0% by mass or more and less than 100% by mass, more preferably 90.0% by mass or more and 99.5% by mass or less, and even more preferably 92.0% by mass or more and 99.0% by mass or less. The content of the methacrylic acid-derived monomer units relative to the total mass of the methacrylic copolymer is preferably more than 0% by mass and 15.0% by mass or less, more preferably 0.5% by mass or more and 10.0% by mass or less, and even more preferably 1.0% by mass or more and 8.0% by mass or less.

[0043] The content of the (meth)acrylic resin (A) is 95 parts by mass or more and less than 97.5 parts by mass, and preferably 95.5 parts by mass or more and 97 parts by mass or less, based on 100 parts by mass of the resin composition.

[0044] The content of the polyethylene oxide (B) is more than 2.5 parts by mass and not more than 5 parts by mass, preferably not less than 3 parts by mass and not more than 4.5 parts by mass, relative to 100 parts by mass of the resin composition.

[0045] [Method for Producing Resin Composition] The method for producing a resin composition according to this embodiment is a method for producing the above-described resin composition, and includes a kneading step of melt-kneading a (meth)acrylic resin (A) and a polyethylene oxide (B) in an extruder. More specifically, the method for producing the resin composition includes, for example, a kneading step of melt-kneading the (meth)acrylic resin (A), the polyethylene oxide (B), and other components that are blended as needed using a known method. Known melt-kneading methods include, for example, a method in which the (meth)acrylic resin (A) and the polyethylene oxide (B) are fed from different feeders and melt-kneaded using a single-screw extruder, a twin-screw extruder, or other multi-screw extruder, or a method in which the mixture is melt-kneaded using a kneader, a Banbury mixer, or the like. In the method for producing a resin composition according to this embodiment, the kneading step is preferably carried out using a single-screw extruder or a twin-screw extruder (hereinafter simply referred to as an "extruder").

[0046] In the method for producing a resin composition according to this embodiment, the extruder includes a cylinder. The extruder may further include a plurality of feeders that supply raw materials to an inlet of the cylinder. That is, the raw materials, (meth)acrylic resin (A) and polyethylene oxide (B), may be introduced into the cylinder through the plurality of feeders. Of the plurality of feeders, the inlet of the feeder for the (meth)acrylic resin (A) is preferably located at the same position as the inlet of the feeder for the polyethylene oxide (B) or downstream of the inlet of the feeder for the polyethylene oxide (B).

[0047] The heater set temperature of the cylinder located closest to the section where the polyethylene oxide (B) is fed and downstream of this section is 110°C or higher and 150°C or lower, preferably 115°C or higher and 145°C or lower, and more preferably 120°C or higher and 140°C or lower. The cylinder may have multiple heaters. The multiple heaters can be set to different temperatures. That is, the set temperature of the cylinder may be adjusted by the set temperatures of the multiple heaters. Note that even if the size of the extruder changes, the set temperature of the heater is substantially equal to the temperature of the feeding section.

[0048] The cylinder may include a screw extending in the axial direction of the cylinder inside the cylinder. As the screw rotates, the resin composition is kneaded and transported from the inlet to the outlet of the cylinder. The screw rotation speed is preferably 100 rpm or more and 300 rpm or less, and more preferably 150 rpm or more and 250 rpm or less.

[0049] [Method for producing resin composition pellets] The method for producing resin composition pellets according to this embodiment includes a pelletizing step in which the resin composition described above is extruded using an extruder to obtain resin composition pellets. More specifically, in the method for producing resin composition pellets, the resin composition described above may be extruded through a die hole of the extruder to extrude strands. The obtained strands may be introduced into a cooling water tank and cooled. Furthermore, the cooled strands may be cut with a strand cutter to obtain resin composition pellets.

[0050] [Molded Article] The molded article according to this embodiment contains the resin composition described above. The molded article can be molded by a known molding method such as extrusion molding, calendar molding, or injection molding using a conventional apparatus used for molding resins. The molded article is preferably molded by injection molding. Examples of injection molding methods include general injection molding, injection foam molding, supercritical injection foam molding, ultra-high speed injection molding, injection compression molding, gas-assisted injection molding, sandwich molding, sandwich foam molding, and insert-outsert molding. The shape of the injection molded article is not particularly limited.

[0051] The molded article according to this embodiment has high transparency and chipping resistance, and further has excellent productivity, and therefore can be suitably used for, for example, vehicle exterior materials such as vehicle lamp covers, visors, and front grilles; vehicle interior materials such as meter covers and in-vehicle display front panels; building materials such as windows and sound insulation walls; signs; furniture such as tabletops; display shelves; exteriors such as carports; display front panels; lighting fixture components such as covers and globes, etc. Examples of vehicle lamp covers include covers for headlights (headlamps), taillights (tail lamps), brake lights (stop lamps), turn signals (blinkers), fog lights (fog lamps), sidelights, and reverse lights.

[0052] [Method for decomposing and recovering a resin composition] The method for decomposing and recovering a resin composition according to this embodiment includes a decomposition step of decomposing the above-described resin composition at a temperature of 380°C or higher, a separation step of separating volatile components and solid matter generated by the decomposition, and a recovery step of recovering a (meth)acrylic acid ester from the volatile components. The (meth)acrylic acid ester is derived from the "alkyl (meth)acrylate having an alkyl group having 1 to 4 carbon atoms" contained in the "(meth)acrylic resin (A)" which is a component of the resin composition.

[0053] More specifically, in the decomposition step, a resin composition is decomposed to obtain a reaction product containing a (meth)acrylic acid ester. The decomposition of the resin composition in the decomposition step is carried out by heating. The temperature at which the decomposition step is carried out is 380°C or higher, preferably 390°C or higher, and more preferably 400°C or higher. A thermal decomposition device may be used in the decomposition step. Examples of the thermal decomposition device include one or more heated extruders, heated rotary kilns, heated vessel reactors, fixed-bed reactors, bubbling fluidized-bed reactors, internal circulating fluidized-bed reactors, circulating fluidized-bed reactors, devices that decompose plastics by causing them to flow down the inner wall of a heated vessel, microwave heating devices, etc.

[0054] More specifically, in the separation step, a volatile component and a solid matter contained in the reaction product containing the (meth)acrylic acid ester generated in the decomposition step are separated. The thermal decomposition apparatus may be provided with a device for separating the volatile component and the solid matter.

[0055] The recovery step may be carried out by separating and purifying the product into a plurality of products having different boiling points.

[0056] The method for decomposing and recovering a resin composition according to this embodiment can contribute to reducing the burden on the environment by being carried out in the above-described manner.

[0057] [Method for Producing Recycled Material] The method for producing recycled material according to this embodiment includes a step of melt-kneading raw materials including crushed material obtained by crushing the above-described molded body.

[0058] The content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less, and preferably 1.00 parts by mass or more and 99.00 parts by mass or less, relative to 100 parts by mass of the raw material.

[0059] The raw material may contain virgin (meth)acrylic resin in addition to the crushed material.

[0060] In one embodiment, the process includes melt-kneading the crushed material with the virgin (meth)acrylic resin. The virgin (meth)acrylic resin refers to a (meth)acrylic polymer that has not been molded into a product such as an automobile or a part thereof and has not been used for any final application after being produced by a process including a polymerization step.

[0061] The above step is carried out by, for example, a method of melt-kneading using a single-screw extruder, a twin-screw extruder, or other multi-screw extruder, or a method of melt-kneading using a kneader, a Banbury mixer, or the like.

[0062] The process may be carried out at a temperature of from 110°C to 290°C, preferably from 130°C to 270°C.

[0063] The method for producing a recycled material according to this embodiment can contribute to reducing the environmental burden while reusing the (meth)acrylic resin by carrying out the method according to the above-described embodiment.

[0064] The present invention includes the following aspects. [1] A resin composition comprising a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 75 parts by mass or more and less than 95 parts by mass per 100 parts by mass of the resin composition, the content of the polyethylene oxide (B) is more than 5 parts by mass and 25 parts by mass or less per 100 parts by mass of the resin composition, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η ０ ) / (cη ０ )...(1) (In the formula, η ０represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B). [2] The resin composition according to [1], wherein the content of the polyethylene oxide (B) is 7 parts by mass or more and 24 parts by mass or less per 100 parts by mass of the resin composition. [3] The resin composition according to [1] or [2], wherein the reduced viscosity (I) of the polyethylene oxide (B) is 2.50 dL / g or more and 20.00 dL / g or less. [4] The resin composition according to any one of [1] to [3], wherein the (meth)acrylic resin (A) comprises a methacrylic copolymer containing: monomer units derived from an alkyl methacrylate having an alkyl group of 1 to 4 carbon atoms; and monomer units derived from a vinyl monomer copolymerizable with the monomer units derived from the alkyl methacrylate having an alkyl group of 1 to 4 carbon atoms; wherein, relative to the total mass of the methacrylic copolymer, the content of the monomer units derived from the alkyl methacrylate is 85.0 mass% or more and less than 100 mass%, and the content of the monomer units derived from the vinyl monomer is more than 0 mass% and 15.0 mass% or less. [5] The resin composition according to [4], wherein the alkyl methacrylate is methyl methacrylate. [6] The resin composition according to [4], wherein the vinyl monomer is methacrylic acid. [7] The resin composition according to [5], wherein the vinyl monomer is methacrylic acid.[8] A resin composition comprising a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 95 parts by mass or more and less than 97.5 parts by mass per 100 parts by mass of the resin composition, and the content of the polyethylene oxide (B) is more than 2.5 parts by mass and not more than 5 parts by mass per 100 parts by mass of the resin composition, the (meth)acrylic resin (A) is a methacrylic copolymer comprising: a monomer unit derived from an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms; and a monomer unit derived from methacrylic acid, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η. ０ ) / (cη ０ )...(1) (In the formula, η ０represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B). [9] A molded article comprising the resin composition according to any one of [1] to [8].

[10] The molded article according to [9], which is used as an exterior material for a vehicle.

[11] A method for producing resin composition pellets, comprising a pelletizing step of extruding the resin composition according to any one of [1] to [8] using an extruder to obtain resin composition pellets.

[12] A method for producing the resin composition according to any one of [1] to [8], comprising: a kneading step of melt-kneading the (meth)acrylic resin (A) and the polyethylene oxide (B) in an extruder, the extruder being equipped with a cylinder, and the heater setting temperature of the cylinder located closest to a section for feeding the polyethylene oxide (B) and downstream of said section is 110° C. or higher and 150° C. or lower.

[13] A method for decomposing and recovering a resin composition, comprising: a decomposition step of decomposing the resin composition according to any one of [1] to [8] at a temperature of 380° C. or higher; a separation step of separating volatile components and solid matter generated by the decomposition step; and a recovery step of recovering a (meth)acrylic acid ester from the volatile components.

[14] A method for producing recycled materials, comprising a step of melting and kneading a raw material containing crushed material obtained by crushing the molded body described in [9], wherein the content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less relative to 100 parts by mass of the raw material.

[15] A method for producing recycled materials, comprising a step of melting and kneading a raw material containing crushed material obtained by crushing the molded body described in

[10] , wherein the content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less relative to 100 parts by mass of the raw material.

[0065] The resin composition, molded body, resin composition pellet manufacturing method, resin composition manufacturing method, resin composition decomposition and recovery method, and recycled material manufacturing method according to the present embodiment are not limited to the above-described embodiments, and various modifications are possible within the scope of the present invention. Furthermore, configurations and methods of embodiments other than those described above may be arbitrarily adopted and combined, and configurations, methods, etc. according to one of the above-described embodiments may be applied to configurations, methods, etc. according to the other of the above-described embodiments.

[0066] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0067] The polyethylene oxide (polyethylene glycol) used as component (B) in the examples and comparative examples is shown in Table 1.

[0068]

[0069] The reduced viscosity (I) (unit: dL / g) of the polyethylene oxide (B) was calculated by the following formula (1).

[0070] I = (η - η ０ ) / (cη ０ ) ... (1)

[0071] In the formula (1), η ０ represents the viscosity (Pa s) of chloroform at 23°C measured in accordance with JIS Z8803. η represents the viscosity (Pa s) of a chloroform solution of polyethylene oxide (B) having a concentration of 0.01 g / dL at 23°C measured in accordance with JIS Z8803. c represents the concentration (0.01 g / dL) of polyethylene oxide (B).

[0072] [(Meth)acrylic Resin (A)] <(Meth)acrylic Resin (A1)> A mixture of 97.5 parts by mass of methyl methacrylate and 2.5 parts by mass of methyl acrylate, 0.016 part by mass of 1,1-di(tert-butylperoxy)cyclohexane, and 0.16 part by mass of n-octyl mercaptan were continuously supplied to a polymerization reactor equipped with a stirrer, and a polymerization reaction was carried out at 175°C for an average residence time of 43 minutes.

[0073] Next, the reaction liquid (partial polymer) discharged from the polymerization reactor was preheated, and then the reaction liquid was supplied to a devolatilizing extruder, where unreacted monomer components were vaporized and recovered, and a pellet-shaped (meth)acrylic resin (A1) was obtained.

[0074] The obtained (meth)acrylic resin (A1) had a content of monomer units derived from methyl methacrylate of 97.5% by mass, a content of monomer units derived from methyl acrylate of 2.5% by mass, and a melt flow rate (MFR) of 2 g / 10 min measured in accordance with JIS K7210.

[0075] <(Meth)acrylic resin (A2)> Methacrylic acid-methyl methacrylate copolymer (containing 4% by mass of methacrylic acid, "ALTUGLUS HT121" manufactured by Trinseo)

[0076] <(Meth)acrylic resin (A3)> Syndiotactic methyl methacrylate polymer (high syndiotacticity, "Parapet (registered trademark) SP-01" manufactured by Kuraray Co., Ltd.)

[0077] Example 1 Production of Resin Composition (Melt-Kneading) 90 parts by mass of the (meth)acrylic resin (A1) produced as described above and 10 parts by mass of PEO-1 were melt-kneaded using a twin-screw extruder (model: TEX30SS-30AW-2V, manufactured by The Japan Steel Works, Ltd.) under the following kneading conditions, extruded into a strand shape, water-cooled to solidify, and cut with a strand cutter to obtain a pellet-shaped resin composition. The contents of (meth)acrylic resin (A1) and polyethylene oxide (B) are shown in Table 2.

[0078] <Melt-kneading conditions> The temperatures of the extruder were set at 130°C, 180°C, 200°C, 230°C, 240°C, 250°C, 255°C, and 250°C, respectively, from the raw material inlet side, for eight heaters arranged at a distance from the raw material inlet to the outlet. The screw rotation speed was set to 200 rpm. The raw material (meth)acrylic resin (A1) was fed using a pellet feeder, and PEO-1 was fed using a powder feeder. Based on the mixing ratio of the (meth)acrylic resin (A1) and PEO-1, the respective feeding rates were set as follows so that the total raw material feeding rate was 14.0 kg / hour. Feeding rate of (meth)acrylic resin (A1): 12.6 kg / hour Feeding rate of PEO-1: 1.4 kg / hour

[0079] <Evaluation of Resin Composition Productivity> The productivity of the resin composition was evaluated based on whether polyethylene oxide (B) could be fed from a powder feeder at a set speed during melt-kneading. The results obtained according to the following evaluation criteria are shown in Table 2. <Evaluation Criteria> ◯: Could be fed without problems at the set speed. ×: Polyethylene oxide slipped and could not be fed at the set speed. −: Could not be evaluated because polyethylene oxide was not used.

[0080] <Production of Molded Article (Injection Molding)> The obtained pellet-like resin composition was molded into a flat plate having a length of 150 mm, a width of 90 mm, and a thickness of 3.0 mm using an injection molding machine (EC130SXII-4A, manufactured by Toshiba Machine Co., Ltd.) under the following molding conditions to obtain a molded article.

[0081] <Injection molding conditions> The temperatures inside the cylinder were set at 60°C, 230°C, 240°C, 250°C, and 250°C, respectively, from the raw material inlet side, for five heaters arranged at a distance from each other between the raw material inlet and the outlet. Other molding conditions were as follows: Injection speed: 90 mm / sec Maximum injection pressure: 200 MPa Holding pressure: 80 MPa Mold temperature: 60°C Cooling time: 45 seconds

[0082] The obtained molded article was cut into a test piece measuring 75 mm x 90 mm x 3 mm, and the transparency and chipping resistance were evaluated using the test piece.

[0083] <Measurement of Transparency of Molded Article> The transparency of a molded article was measured by measuring the diffuse transmittance (Td) (unit: %) of the molded article according to the following formula (2). A Td of 2.0% or less can be said to have good transparency. Td = Haze × Tt (2)

[0084] In the formula, Haze represents the haze (unit: %) of a 3 mm thick molded article measured at 23°C in accordance with JIS K7136. Tt represents the total light transmittance (unit: %) of a 3 mm thick molded article measured at 23°C in accordance with JIS K7361-1.

[0085] <Measurement of chipping resistance of molded body> A chipping test was carried out using a molded body measuring 75 mm x 90 mm x 3 mm. The molded body was placed so that the center of gravity of the molded body was directly below the spray nozzle (inner diameter: 6 mm), and the distance between the spray nozzle and the molded body was adjusted to 370 mm. Then, a pressure of 1 kg / cm was applied. ２ 5 g of No. 8 silica sand manufactured by Tohoku Silica Sand Co., Ltd. was supplied to the injection nozzle and sprayed onto the compact directly below in the air flow.

[0086] The chipping resistance of the molded article was measured by subtracting the diffuse transmittance of the molded article before the chipping test from the diffuse transmittance of the molded article after the chipping test (ΔTd) (unit: %). A ΔTd of less than 20.0% can be said to have good chipping resistance.

[0087] [Examples 2 to 8] Molded articles were produced in the same manner as in Example 1, except that the content of the (meth)acrylic resin (A1) and the type and content of the polyethylene oxide (B) were changed as shown in Table 2, and the transparency, chipping resistance, and productivity of the resin composition were evaluated. The results are shown in Table 2.

[0088] Comparative Example 1 A molded article was produced by injection molding using the (meth)acrylic resin (A1) in the same manner as in Example 1, and the transparency and chipping resistance were evaluated. The results are shown in Table 2.

[0089] [Comparative Examples 2 to 15] Molded articles were produced in the same manner as in Example 1, except that the content of the (meth)acrylic resin (A1) and the type and content of the polyethylene oxide (B) were changed as shown in Table 2, and the transparency, chipping resistance, and productivity of the resin compositions were evaluated. The results are shown in Table 2.

[0090]

[0091] As can be seen from the results in Table 2, the molded articles of Examples 1 to 8, which satisfied all of the constituent requirements of the present invention, showed good results in both transparency and chipping resistance. On the other hand, the molded articles of Comparative Examples 5 and 6 were unable to obtain sufficient transparency. Furthermore, the molded articles of Comparative Examples 1 to 4, 7, 8, and 11 to 14 were unable to obtain sufficient chipping resistance. Note that, for the molded articles of Comparative Examples 9, 10, and 15, polyethylene oxide (B) could not be fed and melt-kneading was not possible, so transparency and chipping resistance could not be evaluated.

[0092] [Examples 9 to 12] Molded articles were produced in the same manner as in Example 1, except that (meth)acrylic resin (A2) was used as the (meth)acrylic resin (A), and the content of (meth)acrylic resin (A2) and the type and content of polyethylene oxide (B) were changed as shown in Table 3. The transparency, chipping resistance, and productivity of the resin composition were evaluated. The results are shown in Table 3.

[0093]

[0094] As can be seen from the results in Table 3, the molded articles of Examples 9 to 12, which satisfied all of the constituent requirements of the present invention, showed good results in terms of transparency, chipping resistance and productivity.

[0095] [Example 13] Molded articles were produced in the same manner as in Example 1, except that (meth)acrylic resin (A3) was used as the (meth)acrylic resin (A), and the content of (meth)acrylic resin (A3) and the type and content of polyethylene oxide (B) were changed as shown in Table 4. The transparency, chipping resistance, and productivity of the resin composition were evaluated. The results are shown in Table 4.

[0096]

[0097] As can be seen from the results in Table 4, the molded article of Example 13, which satisfied all of the constituent requirements of the present invention, exhibited good results in terms of transparency, chipping resistance and productivity.

[0098] From the above, it can be seen that the present invention can provide a resin composition, a molded body, a method for producing resin composition pellets, a method for producing a resin composition, a method for decomposing and recovering a resin composition, and a method for producing recycled materials, all of which have excellent transparency and chipping resistance.

Claims

1. A resin composition comprising a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 75 parts by mass or more and less than 95 parts by mass per 100 parts by mass of the resin composition, the content of the polyethylene oxide (B) is more than 5 parts by mass and 25 parts by mass or less per 100 parts by mass of the resin composition, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η ０ ) / (c ０ )...(1) (In the formula, η ０ represents the viscosity (Pa·s) of chloroform at 23° C. measured according to JIS Z8803. η represents the viscosity (Pa·s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23° C. measured according to JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B).

2. The resin composition according to claim 1, wherein the content of the polyethylene oxide (B) is 7 parts by mass or more and 24 parts by mass or less per 100 parts by mass of the resin composition.

3. The resin composition according to claim 1, wherein the reduced viscosity (I) of the polyethylene oxide (B) is 2.50 dL / g or more and 20.00 dL / g or less.

4. The resin composition according to claim 1, wherein the (meth)acrylic resin (A) comprises a methacrylic copolymer containing: monomer units derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms; and monomer units derived from a vinyl monomer copolymerizable with the monomer units derived from an alkyl methacrylate having an alkyl group with 1 to 4 carbon atoms; and, relative to the total mass of the methacrylic copolymer, the content of the monomer units derived from the alkyl methacrylate is 85.0 mass% or more and less than 100 mass%, and the content of the monomer units derived from the vinyl monomer is more than 0 mass% and 15.0 mass% or less.

5. The resin composition according to claim 4, wherein the alkyl methacrylate is methyl methacrylate.

6. The resin composition according to claim 4, wherein the vinyl monomer is methacrylic acid.

7. The resin composition according to claim 5, wherein the vinyl monomer is methacrylic acid.

8. A resin composition comprising a (meth)acrylic resin (A) and a polyethylene oxide (B), wherein the content of the (meth)acrylic resin (A) is 95 parts by mass or more and less than 97.5 parts by mass per 100 parts by mass of the resin composition, and the content of the polyethylene oxide (B) is more than 2.5 parts by mass and 5 parts by mass or less per 100 parts by mass of the resin composition, the (meth)acrylic resin (A) is a methacrylic copolymer comprising: a monomer unit derived from an alkyl methacrylate having an alkyl group having 1 to 4 carbon atoms; and a monomer unit derived from methacrylic acid, and the reduced viscosity (I) of the polyethylene oxide (B) represented by the following formula (1) is 2.00 dL / g or more and 25.00 dL / g or less. I=(η-η ０ ) / (c ０ )...(1) (In the formula, η ０ represents the viscosity (Pa·s) of chloroform at 23° C. measured according to JIS Z8803. η represents the viscosity (Pa·s) of a chloroform solution of the polyethylene oxide (B) having a concentration of 0.01 g / dL at 23° C. measured according to JIS Z8803. c represents the concentration (0.01 g / dL) of the polyethylene oxide (B).

9. A molded article comprising the resin composition according to any one of claims 1 to 8.

10. The molded article according to claim 9, which is used as an exterior material for a vehicle.

11. A method for producing resin composition pellets, comprising a pelletizing step of extruding the resin composition according to any one of claims 1 to 8 with an extruder to obtain resin composition pellets.

12. A method for producing a resin composition according to any one of claims 1 to 8, comprising a kneading step of melt-kneading the (meth)acrylic resin (A) and the polyethylene oxide (B) in an extruder, the extruder being equipped with a cylinder, and the heater setting temperature of the cylinder located closest to a portion for feeding the polyethylene oxide (B) and downstream of said portion is 110°C or higher and 150°C or lower.

13. A method for decomposing and recovering a resin composition, comprising: a decomposition step of decomposing the resin composition according to any one of claims 1 to 8 at a temperature of 380°C or higher; a separation step of separating the volatile components and solid matter generated by the decomposition step; and a recovery step of recovering a (meth)acrylic acid ester from the volatile components.

14. A method for producing recycled materials, comprising a step of melt-kneading a raw material containing crushed material obtained by crushing the molded body described in claim 9, wherein the content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less per 100 parts by mass of the raw material.

15. A method for producing recycled materials, comprising a step of melt-kneading a raw material containing crushed material obtained by crushing the molded body described in claim 10, wherein the content of the crushed material is 0.01 parts by mass or more and 99.99 parts by mass or less per 100 parts by mass of the raw material.

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