Molded article of thermoplastic bioplastic

Abstract

To provide various molded articles which are obtained by various molding methods, using a thermoplastic bioplastic containing a specific compound derived from plants and a styrenic resin.SOLUTION: There is provided a molded article of a thermoplastic bioplastic. The thermoplastic bioplastic contains a compound (A) represented by general formula (1), and a styrenic resin. A content of the compound (A) with respect to the total amount of the compound (A) and the styrenic resin is 0.1 to 70 mass%. In the formula, R3 is a substituent represented by structural formula: R6-O-, R4 is hydrogen or a substituent represented by structural formula: R7-O-CH2-, and R1, R2, R5, R6, R7 are each independently a substituent containing a benzene ring. In addition, n is an integer of 1 to 7.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to molded articles of thermoplastic bioplastics. [Background technology]

[0002] Currently, thermoplastic plastic molded products that are widely used are difficult to decompose in nature when discarded, and usually require 200 to 400 years for decomposition. In addition, when incinerated, they emit toxic gases such as dioxins, which are a cause of air and soil pollution. In response to this, there is a strong demand for molded products that can be decomposed by living organisms in nature (biodegradable) to replace conventional thermoplastic plastic molded products. Plastics are generally divided into two types: thermoplastic, which becomes plastic when heat is applied, and thermosetting, which hardens when heat is applied. Bioplastics is a general term for plastics whose raw materials are derived from plants, microorganisms, or animals, or biodegradable plastics.

[0003] Plastics derived from plants, microorganisms, or animals do not have sufficient physical and / or chemical properties, so Patent Document 1 proposes mixing a non-bioplastic with a resin derived from plants to produce a biodegradable thermoplastic bioplastic as the bioplastic of the present embodiment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6821724 Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 discloses an injection-molded article of the bioplastic of this embodiment prepared using a hemicellulose derivative (weight average molecular weight Mw: 100,000) as a plant-derived resin and PMMA, PC, PE, PP, or PET as a non-bioplastic, but does not disclose a molded article using a thermoplastic bioplastic containing a compound having a weight average molecular weight of 9,000 or less as a plant-derived resin and a styrene-based resin as a non-bioplastic. In addition, there is no disclosure of a molded article using a molding method other than injection molding. An object of the present invention is to provide a variety of molded articles obtainable by various processing methods using a thermoplastic bioplastic containing a specific compound derived from a plant and a styrene-based resin. [Means for solving the problem]

[0006] In order to solve these problems, the present inventor provides various molded articles obtained by various molding methods using a bioplastic containing a specific compound derived from a plant and a styrene-based resin. The embodiments are as follows. [1] A molded article of thermoplastic bioplastic, The thermoplastic bioplastic contains a compound (A) represented by general formula (1) and a styrene-based resin, The molded article has a content of the compound (A) of 0.1 to 70% by mass based on the total amount of the compound (A) and the styrene-based resin. [ka] (In the formula, R1 is a substituent containing a benzene ring, R2 is a substituent containing a benzene ring, R3 is a substituent represented by the structural formula: R6-O-, R4 is hydrogen or a substituent represented by the structural formula: R7-O-CH2-, R5 is a substituent containing a benzene ring, R6 is a substituent containing a benzene ring, and R7 is a substituent containing a benzene ring. Also, n is an integer of 1 to 7.) [2] The molded article according to [1], wherein the molecular weight of the compound (A) is 9,000 or less. [3] The molded article according to [1] or [2], wherein in the general formula (1), R1, R2, R3, and R5 are each independently a benzyl group or a benzoyl group, and R4 is hydrogen. [4] The molded product according to any one of [1] to [3], which is a sheet-like molded product. [5] The molded product according to [4], which is a sheet-shaped molded product obtained by biaxially stretching the thermoplastic bioplastic. [6] The thickness is 0.5 to 6.0 mm and the bulk density is 0.02 to 0.25 g / cm 3 The molded article according to [4] or [5], which is a foamed sheet comprising: [7] The molded article according to [6], which is obtained by molding the foamed sheet by a thermoforming method. [8] The molded article according to any one of [1] to [7], which is a container. [9] The molded article according to any one of [1] to [8], which is for food packaging purposes.

[10] A method for producing a molded article according to any one of [1] to [9], comprising the step of melt-kneading and molding the compound (A) represented by the general formula (1) and the styrene-based resin. Effect of the Invention

[0007] The present invention can provide a variety of molded articles obtained by various molding methods using a thermoplastic bioplastic containing a specific compound derived from a plant and a styrene-based resin. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] A molded article of a thermoplastic bioplastic according to one embodiment of the present invention (hereinafter, sometimes referred to as "the molded article of this embodiment") is a molded article produced using a thermoplastic bioplastic containing a compound (A) represented by general formula (1) and a styrene-based resin. The weight average molecular weight of the styrene-based resin used in the present invention, as determined by GPC, is preferably in the range of 100,000 to 500,000, more preferably 250,000 to 350,000. The styrene resin may be a single resin or a mixture of multiple copolymers. In the case of a mixture, the molecular weight of the mixture is preferably within the above-mentioned range. In the case of a mixture, a styrene monomer may be copolymerized with a (meth)acrylic monomer such as methacrylic acid or butyl acrylate. Furthermore, a rubber-reinforced styrene resin copolymerized with butadiene rubber may also be used.

[0009] The content of the compound (A) is 0.1 to 70% by mass relative to 100% by mass of the total amount of the compound (A) and the styrene-based resin. The content of the compound (A) is preferably from 0.1 to 70% by mass, more preferably from 1 to 50% by mass, and further preferably from 3 to 25% by mass, based on 100% by mass of the styrene-based resin.

[0010] In addition, the content of the compound (A) in the molded product of the thermoplastic bioplastic is 0.1 to 70% by mass. If the content of the compound (A) is less than 0.1% by mass, the biomass ratio (plant ratio) is low and it is difficult to call it a "bioplastic," while if the content is 70% by weight or more, the physical properties (especially mechanical properties) of the bioplastic are inferior to those of polystyrene, which is not preferable. The content of the compound (A) is preferably 1 to 50% by mass, more preferably 3 to 25% by mass, based on 100% by mass of the styrene-based resin.

[0011] [ka]

[0012] In the formula (1), R1 is a substituent containing a benzene ring, R2 is a substituent containing a benzene ring, R3 is a substituent represented by the structural formula R6-O-, R4 is hydrogen or a substituent represented by the structural formula R7-O-CH2-, R5 is a substituent containing a benzene ring, R6 is a substituent containing a benzene ring, and R7 is a substituent containing a benzene ring. Also, n is an integer of 1 to 7.

[0013] (Thermoplastic bioplastics) The thermoplastic bioplastic used in the molded article of this embodiment (sometimes referred to as the "bioplastic according to this embodiment") contains the compound (A) represented by the above general formula (1) and a styrene-based resin.

[0014] [Compound (A)] The molecular weight of the compound (A) (also referred to as "compound (A)") represented by the above general formula (1) contained in the bioplastic according to this embodiment may be 9000 or less, 7000 or less, 5000 or less, 4000 or less, or 2000 or less. This range is preferable because it is unlikely to become extremely viscous when mixed with a styrene-based resin, and it is easy to maintain the melt viscosity required for molding. The molecular weight of compound (A) is preferably 400 or more, more preferably 500 or more. In compound (A), R1 is a substituent containing a benzene ring. R2 is a substituent containing a benzene ring. R3 is a substituent represented by the structural formula: R6-O-. R4 is hydrogen or a substituent represented by the structural formula: R7-O-CH2-. R5 is a substituent containing a benzene ring. R6 is a substituent containing a benzene ring, and R7 is a substituent containing a benzene ring.

[0015] In addition, n is an integer of 1 to 7, and may be an integer of 1 to 5. When there are multiple compounds (A) represented by general formula (1), compounds with different integers may be mixed and used. In the case of a mixture of compounds (A) represented by general formula (1), the average is a decimal number rather than an integer. For example, a mixture of equal amounts of a compound with n=1 and a compound with n=2 can be considered as (1+2) / 2=1.5. For example, the structural formula when n=2 is as shown in the following formula (2) (hereinafter, also referred to as "compound (2)").

[0016] [ka]

[0017] In formula (1) and formula (2), R1, R2, R5, R6 and R7 may be the same or different. Examples of the substituent containing a benzene ring include a phenyl group, a benzyl group, a para-methoxyphenylbenzyl group, a benzoyl group, an indanyl group, a styryl group, an anilino group, a trityl group, an alkyl group having a phenyl group as a substituent, and further those in which the hydrogen atom on the benzene ring is replaced with an alkyl group or a halogen atom. Among these, a benzyl group and a benzoyl group are preferred. A benzoyl group is preferred because it is particularly easy to substitute when benzaldehyde or benzoic acid is used, and because the compounds (A) represented by general formula (1) are easily bonded to each other via a carbonyl group, improving strength and heat resistance. The benzoyl group has the following structural formula (3). The molecular weight of the benzoyl group is 105.

[0018] [ka]

[0019] Resin formula (1) in which R1, R2, R5, R6 and R7 are all benzoyl groups, when n=1, is represented by the following structural formula (4) or structural formula (5) (also referred to as "compound (4)" and "compound (5)", respectively). In the case of compound (4), the molecular weight is 566. In the case of compound (5), the molecular weight is 668.

[0020] [ka]

[0021] [ka]

[0022] In the above explanation, the stereoisomers of the above compounds (A), (2), (4) and (5) have not been explained. Here, the present inventor will explain about stereoisomers. As is already known, stereoisomers that arise by taking a cyclic structure include α-type and β-type, and both α-type and β-type exist in nature. If one were to say so, the α-type is often in a paste or sticky gel state, and is somewhat difficult to knead with styrene-based resins, making it difficult to use. On the other hand, the β-type is easy to become powder, and the powder is easy to knead with styrene-based resins, making it easy to use. However, if the α-type is mixed with the β-type, the mixture is easy to become powder, so the α-type is also easy to use. In addition, as a raw material for producing the compound (A) represented by the general formula (1), there is a commercially available product in a mixed state of the α-type and the β-type, so it may be used.

[0023] Stereoisomers (optical isomers) that are mirror images are sometimes called D- and L-isomers. Only D-isomers exist in nature, and L-isomers are artificially obtained by chemical reactions. Compound (A) represented by general formula (1) in this embodiment is a D-isomer because it is derived from plants such as corn cobs and has biodegradability as one of its features, as explained in the examples. For this reason, β-D-xylose and β-D-glucose are preferable as raw materials for compound (A), and α-D-xylose and α-D-glucose can also be used. That is, it is also possible to use a mixture of β-D-xylose and α-D-xylose, or a mixture of β-D-glucose and α-D-glucose. β-L-xylose using an artificially obtained L-isomer may also be used.

[0024] <Method for producing compound (A)> The compound (A) according to the present embodiment can be produced from raw materials derived from plants and is roughly classified into two types. One is a type of hemicellulose (n is 2 or more) having a repeating unit of the following structural formula (6) (hereinafter, sometimes referred to as xylose (n=1)). n is an integer from 1 to 7.

[0025] [ka]

[0026] Hemicellulose is a general term for polysaccharides that make up about 20-50% of plants. Hemicellulose is found in the cell walls of plants, such as trees or wood, grains, grasses, ferns, and gymnosperms. Hemicellulose is a structural component of wood. Plants that contain large amounts of hemicellulose include broad-leaved trees, corn cobs, bamboo, and cotton seed husks. Hemicellulose of formula (6) can be obtained by extracting and separating it from these plants using standard methods. Hemicellulose has good biodegradability. Hemicellulose has a faster biodegradation rate than cellulose and lignin, and has good biodegradability from low temperatures (for example, 5°C) to high temperatures. Even at room temperature, hemicellulose is decomposed by microorganisms and becomes water and carbon dioxide after three months. When buried in soil, hemicellulose is decomposed by microorganisms in the soil. Hemicellulose is also decomposed by microorganisms in seawater. Hemicellulose is an environmentally friendly material.

[0027] The other is a type of cellulose (n is 2 or more) or starch (n is 2 or more) having a repeating unit of the following structural formula (7) (hereinafter, sometimes referred to as glucose (n=1)), where n is an integer from 1 to 7.

[0028] [ka]

[0029] Cellulose or starch is a major component of the cells and cell walls of plants, such as trees or wood, corn, sugar cane, grains, grasses, ferns, gymnosperms, fruits, etc. The cellulose or starch of formula (7) can be obtained by extraction and separation from these plants using conventional methods.

[0030] Once a compound represented by formula (6) or (7) with a predetermined repeat number n is prepared, its hydroxyl group (-OH) is reacted with, for example, benzoyl chloride, benzaldehyde, or benzoic acid to convert it to a benzoyl group (benzoylation). This reaction proceeds easily, and compound (A) can be easily obtained.

[0031] Benzoyl chloride is generally produced from benzaldehyde or benzoic acid. Benzaldehyde is a typical aromatic aldehyde, also known as bitter almond oil. It is distributed in the plant kingdom as the main component of the essential oil of peach or apricot core, and is contained in some essential oils such as neroli oil. It is also contained in sugar cane, corn, and some trees. Benzoyl chloride is obtained by reacting this benzaldehyde with chlorine in a conventional manner. Similarly, benzoic acid is a plant-derived component, and benzoyl chloride can be obtained by reacting benzoic acid with a chlorine compound in a conventional manner. You will get zoil.

[0032] Compound (4) or compound (5) in which R1, R2, R5, R6, and R7 are all benzoyl groups can be said to be derived from plants. Although not described in detail, the hydroxyl group (-OH) can be reacted with chlorobenzene or the like to replace the hydrogen with a phenyl group, or with benzyl chloride or the like to replace the hydrogen with a benzyl group.

[0033] [Styrene-based resin] The styrene-based resin contained in the bioplastic according to this embodiment is a thermoplastic plastic. In the present invention, the styrene resin refers to all styrene resins distributed in the market, specifically, unnecessary styrene resin products and used styrene resin products (sometimes referred to as discarded styrene resin or waste styrene resin). Examples of styrene monomers used in styrene resins include styrene, α-methylstyrene, paramethylstyrene, ethylstyrene, propylstyrene, butylstyrene, chlorostyrene, and bromostyrene. The styrene may also be a copolymer obtained by copolymerizing a comonomer copolymerizable with styrene with styrene. Examples of comonomers copolymerizable with styrene include (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate, aromatic vinyl monomers other than styrene such as α-methylstyrene, o-, m-, and p-methylstyrene, unsaturated fatty acids such as (meth)acrylic acid, maleic acid, and fumaric acid, unsaturated difatty acid anhydrides such as maleic anhydride and itaconic anhydride, and unsaturated difatty acid imides such as N-phenylmaleimide. These comonomers are often used alone or in combination of two or more. The styrene-based resin preferably has a weight average molecular weight determined by GPC in the range of 100,000 to 500,000, and more preferably 250,000 to 350,000. An example of such a styrene-based resin is DIC Styrene XC-515 manufactured by DIC Corporation. It is easily available as a commercial product.

[0034] [Other ingredients] The thermoplastic bioplastic according to this embodiment may contain other resins as long as the gist of the present invention is not impaired.

[0035] The other components are, for example, other resins and additives. As the other resins, resins such as acrylic resins, styrene resins, or copolymers of styrene resins and acrylic resins may be added to improve strength and heat resistance. The additives are plasticizers, dispersants, antibacterial agents, compatibilizers, lubricants, flow auxiliaries, release agents, stabilizers, flame retardants, transparency improvers, yellowing inhibitors, UV absorbers, antistatic agents, antifake agents, pigments, dyes, fluorescent dyes, etc. The additives may be those used for conventional plastics, and biomass compounds such as citric acid derivatives may be used as plasticizers to increase the biomass content.

[0036] [Method of manufacturing plastic bioplastics] The plastic bioplastic according to the present embodiment is produced by kneading the compound (A), the styrene-based resin, and optionally other components under heating. Prior to kneading, it is preferable to premix the resin (1), the styrene-based resin, and optionally other components.

[0037] In premixing, for example, powdered compound (A) is placed in a bag of pelletized styrene resin, and the two can be easily mixed by an operator shaking the bag. Of course, powdered compound (A) and pelletized styrene resin can also be mixed using a device such as a mixer or stirrer. Examples of mixers or stirrers include ribbon blenders, drum tumblers, Henschel mixers, super mixers, tumblers, and V-shaped blenders.

[0038] Next, the premixed compound (A), the styrene-based resin, and an optional third component are kneaded together. For example, the kneading can be performed by a method using a single-screw kneading extruder, a twin-screw kneading extruder, or a multi-screw kneading extruder. The heating temperature during kneading is appropriately selected usually within the range of 100 to 300°C, preferably within the range of 150 to 250°C, and more preferably within the range of 180 to 230°C.

[0039] Kneading is important, and it is preferable that the compound (A) and the styrene-based resin are uniformly dispersed at the molecular level by kneading. By being uniformly dispersed at the molecular level, when the inherently biodegradable compound (A) is biodegraded by microorganisms, the styrene-based resin will also be decomposed at the molecular level. This advances the biodegradation of the entire bioplastic of this embodiment. That is, when the compound (A) is uniformly dispersed at the molecular level in the styrene-based resin, it plays a role in imparting biodegradability to the petroleum-derived styrene-based resin. It is presumed that when the compound (A) is biodegraded, the styrene-based resin will also break apart at the molecular level and dissolve in water or soil due to the molecules of the compound (A) penetrating between the molecules of the styrene-based resin.

[0040] Whether or not the compound (A) is uniformly dispersed in the styrene-based resin at the molecular level can be determined by evaluating the optical uniformity, total light transmittance, haze, and birefringence retardation of the bioplastic of the present embodiment, and can also be evaluated by an electron microscope or an atomic force microscope.

[0041] The bioplastic of this embodiment may be in the form of a block, plate, film, thread, string, cylindrical pellet, powder, particle, etc. From the viewpoint of storage, distribution, etc., a particle or cylindrical pellet is preferable. The cylindrical pellet preferably has a diameter of 0.2 to 3 mm and a length of 0.2 to 5 mm, for example.

[0042] (molded product) The bioplastic of this embodiment can be processed into a practically useful molded product by a conventionally known method, such as extrusion molding, injection molding, two-color injection molding, sandwich molding, hollow molding, compression molding, vacuum molding, rotational molding, powder slush molding, foam molding, laminate molding, calendar molding, blow molding, etc. If necessary, it may be processed into foam, powder, stretching, adhesion, printing, painting, plating, etc. By such molding methods, it can be used as a wide variety of molded products such as sheets, films, injection molded products of various shapes, hollow molded products, pressure molded products, vacuum molded products, extrusion molded products, and foam molded products, and these molded products can be used as various packaging materials for industrial use, food use, home appliances, automobiles, building materials, sports, leisure, etc., and various containers.

[0043] [Sheet-shaped molded products] <Non-stretched sheet> The unstretched sheet can be produced by melt-extruding the pellets of the bioplastic of this embodiment obtained above with an extruder, melt-extruding them into a sheet shape through a T-die, and then cooling them with a cooling roll, etc. The cooling temperature is preferably 70 to 90°C.

[0044] <Biaxially oriented sheet> A biaxially stretched sheet can be obtained by melt-extruding in an extruder, followed by biaxial stretching in both the longitudinal and transverse directions in a stretching machine. For example, the bioplastic of this embodiment is first fed to an extruder, and melt-extruded into a sheet from a T-die. At this time, the sheet before stretching is cast so as to have a predetermined thickness. Thereafter, the sheet is cooled to a temperature at which biaxial stretching is possible, for example, 110 to 150°C, and stretched in the longitudinal direction (flow direction) and transverse direction (cross direction to the flow direction) to obtain the sheet.

[0045] The stretching method can be to melt-extrude the bioplastic of this embodiment into a sheet, and then perform simultaneous biaxial stretching or sequential biaxial stretching. In the case of sequential biaxial stretching, it is common to first perform longitudinal stretching and then transverse stretching. In particular, for biaxially stretched styrene-based sheets, longitudinal stretching using rolls is followed by transverse stretching using a tenter. The tenter method has the advantage of being able to produce wide products and being highly productive.

[0046] As a method for longitudinal stretching using rolls, there is a method in which a low-speed roll and a high-speed roll are rotated in the same direction to pass the resin flat and stretch it, and a method in which a low-speed roll and a high-speed roll are rotated in opposite directions to pass the resin crosswise and stretch it. Any combination of one stage or multiple stages, flat or cross can be used.

[0047] As specific stretching conditions, the stretch ratio varies depending on the purpose, but is usually 1.5 to 15 times, more preferably 4 to 10 times in terms of areal ratio. In the case of sequential stretching, the stretch ratio in the machine direction is 1.2 to 5 times, preferably 1.5 to 3.0 times, and the stretch ratio in the cross direction to the machine direction is 1.2 to 5 times, preferably 1.5 to 3.0 times. In simultaneous biaxial stretching, the stretch ratio in each direction is 1.5 to 5 times. In addition, the temperature conditions at this time are preferably such that the orientation relaxation stress measured in accordance with ASTM D-1504 is 0.2 to 2.0 MPa, more preferably 0.4 to 1.0 MPa. If the orientation relaxation stress is less than 0.2 MPa, the impact resistance of the sheet is likely to be insufficient, and if it exceeds 2.0 MPa, the sheet is likely to be cut during stretching and may have poor secondary formability. On the other hand, when the pressure is in the range of 0.4 to 1.0 MPa, not only the foldability of the obtained sheet is good, but also the moldability of the sheet itself is very good, which is more preferable.

[0048] In this case, for example, the raw sheet before stretching is stretched at the above-mentioned ratio in the machine direction at a stretching temperature of 110 to 150°C, and then stretched at the above-mentioned ratio in the cross direction crossing the machine direction at a stretching temperature of 110 to 150°C.

[0049] The thickness of the biaxially oriented sheet made of bioplastic of this embodiment is preferably 0.1 to 0.5 mm. If necessary, the biaxially oriented sheet may be laminated with the same or different thermoplastic resins by coextrusion, dry lamination, etc. If necessary, the biaxially oriented sheet may be coated with an anti-fogging agent, etc.

[0050] The obtained biaxially oriented sheet can be pressure molded in a mold of a given shape under the same conditions as those for conventional biaxially oriented styrene resin sheets to easily obtain desired containers, lids, etc.

[0051] [Foamed molded products] When forming a foamed sheet, the bioplastic of this embodiment is impregnated with a foaming agent, fed to an extruder, heated to melt and knead, and then extruded through a circular die, T-die, or the like while foaming, thereby producing an extruded foam sheet by a conventional foam molding method.

[0052] As the foaming agent, a general-purpose foaming material can be used. For example, lower hydrocarbons such as propane, butane, pentane, and hexane, halogenated hydrocarbons such as methyl chloride, dichloromethane, trichloromonofluoromethane, and dichlorodifluoromethane, and carbon dioxide can be used. In the case of handling operations using a normal extruder or low expansion ratios, chemical foaming using a sodium bicarbonate foaming agent that generates carbon dioxide when heated is preferred.

[0053] Furthermore, in order to control the amount and size of foam cells, an inorganic compound can be used as a nucleating agent, and a preferred inorganic compound is talc.

[0054] There is also no particular restriction on the order of mixing the bioplastic of this embodiment and the foaming agent. Examples of the order include a method in which a foaming agent is added to the bioplastic of this embodiment and the mixture is subjected to a melt mixer, or a method in which a master batch is prepared in advance by kneading a high concentration of a foaming agent into a portion of the bioplastic of this embodiment, and then this master batch is kneaded with the remaining bioplastic of this embodiment and then foam-molded.

[0055] If necessary, a method in which other additives are melt-kneaded at the same time, or a method in which a master batch is prepared in advance by melt-kneading the bioplastic of this embodiment with other resins and additives, and then this master batch, the bioplastic of this embodiment, and a foaming agent are melt-kneaded and foam-molded may be used.

[0056] The temperature during melt kneading is preferably in the range of 180 to 260°C, and is preferably 180 to 230°C in order to prevent thermal degradation of the bioplastic of this embodiment and from the viewpoint of carbon dioxide generation efficiency when a sodium bicarbonate-based blowing agent is used.

[0057] The die temperature of a circular die, a T-die or the like is preferably in the range of 120 to 150° C. in order to perform stable expansion molding.

[0058] The expansion ratio when producing a foamed sheet is not particularly limited, but is preferably 4 to 50 times from the viewpoint of maintaining mechanical strength, weight reduction by foaming, and moldability. The thickness of the foam sheet is 0.5 to 6.0 mm, and the bulk density is 0.02 to 0.25 g / cm 3 It is preferable that:

[0059] The bioplastic foamed sheet of the present embodiment obtained above can be secondary processed by thermoforming to form a molded product. As the thermoforming method, a hot plate contact heat forming method, a vacuum forming method, a vacuum pressure forming method, a plug assist molding method, etc. are preferably used.

[0060] The shape of the molded product is not particularly limited and may be various packs, cases, etc. From the viewpoint of moldability and heat resistance, which are characteristics of the styrene-based foamed sheet of the present invention and the molded product thereof, it is preferable that the molded product is for food packaging, and it is particularly preferable that the molded product is used as a container tray or a container.

[0061] It is also possible to laminate a film to the front and back of the obtained foamed sheet or a molded product obtained by secondary molding of the same in order to improve mechanical strength, chemical resistance, etc. Specifically, it is also possible to thermally laminate the bioplastic inflation film of this embodiment, or to laminate an olefin-based film (CPP) using an adhesive.

[0062] [Injection molded products] Furthermore, the bioplastic of this embodiment can be processed by cast extrusion, extrusion molding, injection molding, or the like to produce molded articles of the desired shape, but injection molding is preferred as a processing method because it has a good yield.

[0063] [Injection molding method] The injection molding method is not limited in any way, but it is preferable to use a mold having multiple pin gates, side gates, etc., so that the molten bioplastic of this embodiment can be uniformly flowed and molded in a well-balanced manner. In addition, in order to obtain a molded product with good dimensional accuracy and no cloudiness due to gas, it is preferable to use a mold having a vacuum hole so that the mold cavity can be decompressed when the molten bioplastic of this embodiment is injected. Furthermore, a mold having a hot runner is preferable because no scrap material is generated and there is little loss during production. When using a hot runner, a needle valve that closes the gate after the molten bioplastic of this embodiment has finished flowing into the mold cavity is also preferably used so as not to generate gate marks.

[0064] [Blown film] <Film manufacturing method> The bioplastic of this embodiment can be easily molded into films, sheets, etc. by inflation molding, or the bioplastic of this embodiment can be molded into a sheet, and then the sheet can be reheated and biaxially stretched in the longitudinal and transverse directions to obtain the film of this embodiment. In this embodiment, the conditions for producing the bioplastic of this embodiment are not particularly limited, but for example, using an inflation processing machine, the bioplastic of this embodiment for film is passed through an extruder preheated to 160 to 230°C, and the molten resin extruded into a tube shape from a circular die is inflated with air pressure while being taken up vertically, and then wound up, whereby a cylindrical film having a diameter larger than the die aperture can be continuously produced. The thickness and stretching degree of the film are adjusted by the screw rotation speed, take-up speed, and air pressure. The film after inflation processing can also be further stretched at 100 to 150°C to form a biaxially stretched film.

[0065] For example, the bioplastic of this embodiment can be made by attaching a ring-shaped double cylinder to the tip of a Nakatani Machinery 20 mm extruder, inflating the resin coming out of the double cylinder, cooling it, and winding it up on a take-up machine to obtain an inflation film with a thickness of 25 μm for each example.

[0066] [Use of molded products] The use of the molded article of the present embodiment is not limited at all, and it is useful as a material for molding various molded articles such as home appliance parts, electric / electronic parts, automobile parts, machine / mechanism parts, cosmetic containers, food packaging containers, etc. For example, it can be suitably used for pipe materials such as hoses and tubes; civil engineering materials such as artificial turf, mats, tunnel sheets, waterproof sheets, and roofing; building materials such as furniture, flooring materials, and foam sheets; automobile interior and exterior parts such as carpet backing materials, door panel waterproof sheets, mud guards, and moldings; home appliances such as packings and vibration-damping sheets; breaker parts, switch parts, motor parts, ignition coil cases, power plugs, power outlets, coil bobbins, connectors, relay cases, fuse cases, flyback transformer parts, focus block parts, distributor caps, harness connectors; cosmetic containers for holding beauty creams, hand creams, etc.; food packaging containers for holding puddings, jellies, etc. Furthermore, it is useful for housings, casings, or chassis that are becoming thinner, such as the housings, casings, or chassis of electronic and electrical products (for example, home appliances and office automation equipment such as telephones, personal computers, printers, fax machines, copy machines, televisions, video decks, and audio equipment, or parts thereof).It is also useful as machine and mechanism parts of home appliances and office automation products such as printer housings, fixing unit parts, and fax machines, which require particularly excellent heat resistance and flame retardancy. EXAMPLES

[0067] The present embodiment will be further described below with reference to examples. First, various compounds (A) according to this embodiment were produced in Production Examples 1 to 15. (Production Example 1) <Compound (4) Production: Benzoylated xylose system> D-xylose (n=1) was prepared as the raw material. This D-xylose is a mixture of β-D-xylose and α-D-xylose. This D-xylose is extracted and purified from corn cobs, then decomposed using enzymes, and is commercially available.

[0068] 60 g of this D-xylose powder was added to 400 ml of pyridine and stirred, and the D-xylose was dissolved in the pyridine to obtain a xylose solution. The beaker is placed in an ice bath with ice packs around it to cool it down. is doing.

[0069] Separately, benzaldehyde obtained by cultivating Ilex arbutifolia was oxidized to produce benzoic acid. Benzoic acid was then reacted with thionyl chloride to produce benzoyl chloride (liquid). Benzaldehyde or benzoic acid can be extracted and obtained from other plants besides Ilex arbutifolia.

[0070] This benzoyl chloride (liquid) is preferable in terms of improving the biomass degree because the elements other than chlorine are derived from natural products. Benzoyl chloride derived from natural products and benzoyl chloride derived from petroleum are commercially available. Benzoyl chloride derived from natural products is produced from benzaldehyde and benzoic acid derived from natural products. Most petroleum-derived benzoyl chloride is also produced in part from benzoic acid and benzaldehyde derived from natural products. In such cases, the amount of carbon dioxide generated during production is small, and the biomass degree is 70% to 95%, which is higher than that of natural products. It is slightly lower than naturally occurring benzoyl chloride.

[0071] 220 ml of benzoyl chloride derived from natural products was slowly dripped into the xylose solution. The xylose solution to which 220 ml of benzoyl chloride had been dripped was then stirred for 12 hours. This resulted in a reaction solution in which benzoyl chloride had reacted with xylose. The reaction is a chemical reaction in which the hydrogen atoms H of the OH groups (4 in total) of xylose react with the chlorine atoms Cl of benzoyl chloride. This results in benzoylated xylose (formula (4)), in which the H part of the OH group of xylose has become a benzoyl group. The HCl generated during this process is trapped in pyridine.

[0072] Next, the reaction solution was added to 3 liters of pure water. Then, water-insoluble crystals were precipitated. The solution containing the precipitate was suction filtered. Then, pure water was added three times to wash the filtered precipitate. The washed precipitate was dissolved in 200 ml of ethyl acetate to obtain a solution. Then, 2.5 liters of methyl alcohol was added to this solution. Then, white crystals were precipitated. The solution containing the precipitate was suction filtered. Next, the filtered precipitate was washed with methanol. The white solid precipitate thus obtained was placed in a vacuum dryer and dried. In this way, 150 g of white powder of benzoylated xylose (compound (4)) was obtained.

[0073] In this benzoylated xylose, R1, R2, R5, and R6 are benzoyl groups, and R4 is hydrogen.

[0074] (Production Example 2) <Compound (5) Production: Benzoylated Glucose System> D-glucose (n=1) was prepared as the raw material. This D-glucose is a mixture of β-D-glucose and α-D-glucose. This glucose is extracted and purified from corn or sugar cane, then decomposed using enzymes, and is commercially available.

[0075] 60 g of this glucose powder was added to 400 ml of pyridine and stirred to dissolve the glucose in the pyridine, resulting in a glucose solution. The pyridine was placed in a glass beaker, and the beaker was surrounded by ice packs to create an ice bath.

[0076] Separately, benzaldehyde obtained by cultivating yanitsuke was oxidized to produce benzoic acid. Benzoic acid was then reacted with thionyl chloride to produce benzoyl chloride (liquid). Benzaldehyde or benzoic acid can be extracted and obtained from other plants in addition to yanitsuke. The obtained benzoyl chloride has a high biomass content, as in Example 1.

[0077] 220 ml of this benzoyl chloride was slowly dropped into the glucose solution. After that, the mixture was stirred for 12 hours. This resulted in a reaction solution in which benzoyl chloride and glucose had reacted. The reaction is a chemical reaction in which the hydrogen atoms H of the OH groups (total of five) of glucose react with the chlorine atoms Cl of benzoyl chloride. This results in benzoylated glucose, in which the H of the OH groups of glucose has become a benzoyl group. The HCl generated during this process is trapped in pyridine.

[0078] Next, the reaction solution was added to 3 liters of pure water. Then, water-insoluble crystals were precipitated. The solution containing the precipitate was suction filtered. Then, pure water was added three times to wash the filtered precipitate. 200 ml of ethyl acetate was added to the washed precipitate. The benzoyl glucose was dissolved in 2.5 liters of methanol to obtain a solution. Then, 2.5 liters of methyl alcohol was added to this solution. Then, white crystals were precipitated. The solution containing the precipitate was suction filtered. Then, the filtered precipitate was washed with methanol. The white solid precipitate thus obtained was dried in a vacuum dryer. Thus, 150 g of white powder of benzoylated glucose (compound (5)) was obtained.

[0079] In this benzoylated glucose (compound (5)), R1, R2, R5, R6, and R7 are benzoyl groups. R3 is a benzoyl group -O-, and R4 is a benzoyl group -O-CH-.

[0080] (Production Example 3) <Production of Compound (A): Benzylated Xylose> Benzylated xylose is produced in which the H moiety of the OH group of xylose is replaced with a benzyl group. For example, this benzylated xylose was produced as follows.

[0081] D-xylose (n=1) was prepared as the raw material. 60 g of this D-xylose was dissolved in 300 ml of 50% by mass aqueous sodium hydroxide solution. A catalytic amount of tetramethylammonium iodide was then added. The mixture was stirred in an oil bath at 40°C for 2 hours, and the H part (hydrogen) of the OH group of xylose was replaced with Na. The oil bath was stopped and the mixture was allowed to cool to room temperature. After that, 6.5 equivalents of benzyl chloride were added to the cooled mixture. Benzyl chloride can be obtained by reducing benzaldehyde derived from plants to obtain benzyl alcohol, which can then be reacted with a chlorine compound in the usual manner.

[0082] A catalytic amount of sodium iodide is added to the mixture to increase the reactivity of benzyl chloride. The temperature of the mixture is gradually raised to 110°C while replacing with nitrogen gas. The mixture is then stirred at 110°C for 5 hours. After the reaction is complete, the mixture is allowed to cool and then cooled in an ice bath. Diethyl ether is then added to the mixture and stirred. When the stirring is stopped and the mixture is left to stand for a while, the mixture separates into two layers: a supernatant and a precipitate. The supernatant is then decanted, and the remaining mixture is suction filtered. The filtered precipitate is washed by adding diethyl ether again. The washing, decantation, and suction filtration are repeated until the solution to which diethyl ether has been added becomes transparent. After the solution becomes transparent, the precipitate is further suction filtered and washed with methanol. The methanol solution is washed until it becomes transparent, and the methanol solution is suction filtered. The precipitate is dissolved in acetone and precipitated with water, and the precipitate is collected. The precipitate was dried in a vacuum dryer at 45° C. for 24 hours to obtain 150 g of benzylated xylose.

[0083] (Production Example 4) <Production of Compound (A): Benzylated Glucose System> Benzylated glucose is produced in which the H moiety of the OH group of glucose is replaced with a benzyl group. This benzylated glucose is produced, for example, as follows.

[0084] D-glucose (n=1) was prepared as the raw material. 60 g of D-glucose was dissolved in 300 ml of 50% by mass aqueous sodium hydroxide solution. A catalytic amount of tetramethylammonium iodide was added. This mixed solution was stirred in an oil bath at 40°C for 2 hours, and the hydrogen in the hydroxyl group OH of glucose was replaced with Na. The oil bath was stopped and the mixed solution was allowed to cool to room temperature, after which 6.5 equivalents of benzyl chloride were added to the cooled mixed solution. Benzyl chloride can be obtained by reducing benzaldehyde derived from plants to obtain benzyl alcohol, which can then be reacted with a chlorine compound in the usual manner.

[0085] A catalytic amount of sodium iodide is added to the mixture to increase the reactivity of benzyl chloride. The temperature of the mixture is gradually raised to 110°C while replacing with nitrogen gas. The mixture is then stirred at 110°C for 5 hours. After the reaction is complete, the mixture is allowed to cool and then cooled in an ice bath. Diethyl ether is then added to the mixture and stirred. When the stirring is stopped and the mixture is left to stand for a while, the mixture separates into two layers: a supernatant and a precipitate. The supernatant is then decanted, and the remaining mixture is suction filtered. The filtered precipitate is washed by adding diethyl ether again. The washing, decantation, and suction filtration are repeated until the solution to which diethyl ether has been added becomes transparent. After the solution becomes transparent, the precipitate is further suction filtered and washed with methanol. The methanol solution is washed until it becomes transparent, and the methanol solution is suction filtered. The precipitate is dissolved in acetone and precipitated with water, and the precipitate is collected. The precipitate was dried in a vacuum dryer at 45° C. for 24 hours to obtain 150 g of benzylated glucose.

[0086] (Production Example 5) <Production of Compound (A): Benzoylated Hemicellulose (n=3)> In the above Production Example 1, D-xylose (n=1) was prepared as a raw material. In contrast, in Production Example 5, a commercial product (hereinafter referred to as hemicellulose with n=3) in which D-xylose (n=1), hemicellulose (n=2) and hemicellulose (n=3) were mixed was prepared as a raw material. By adjusting the conditions for catalytic decomposition after extraction and purification from corn cobs, hemicellulose with n=3 (commercial product) can be obtained.

[0087] Benzoylated hemicellulose (n=3) was produced in which the H moiety of the OH group of this hemicellulose (n=3) was replaced with a benzoyl group. This benzoylated hemicellulose (n=3) was produced by the same method as that for benzoyl xylose described in Production Example 1.

[0088] (Production Example 6) <Preparation of Compound (A): Benzoyl Cellulose (n=3)> In the above Production Example 2, D-glucose (n=1) was prepared as the raw material. In contrast, in Production Example 6, a commercial product (hereafter referred to as cellulose with n=3) containing a mixture of D-glucose (n=1), cellulose (n=2), and cellulose (n=3) was prepared as the raw material. Cellulose with n=3 (commercial product) can be obtained by adjusting the conditions for decomposition with a catalyst after extraction and purification from trees.

[0089] Benzoylated cellulose (n=3) is produced in which the H moiety of the OH group of this cellulose (n=3) is replaced with a benzoyl group. This benzoylated cellulose was produced by the same method as that for benzoylated glucose described in Production Example 2.

[0090] (Production Example 7) <Production of Compound (A): Benzoylated Starch (n=3)> As is commonly known, the difference between starch and cellulose is that although the structural unit is the same, D-glucose (grape sugar), starch is made up of multiple molecules of α-D-glucose linked together in a spiral shape with repeated α-1,4 bonds, while cellulose is made up of multiple molecules of the optical isomer {β-D-glucose linked together in a linear shape with repeated {β-1,4 bonds.

[0091] The raw material is a commercially available mixture of D-glucose (n=1), starch (n=2), and starch (n=3) (hereafter referred to as n=3 starch). After extraction and purification from corn, the conditions for catalytic decomposition are adjusted to obtain n=3 starch (commercial product). Benzoylated starch (n=3) is produced in which the H moiety of the OH group of this starch (n=3) is replaced with a benzoyl group. The benzoylated starch (n=3) was produced by the same method as that for benzoylated glucose described in Production Example 2.

[0092] In this benzoylated starch (n=3), R1, R2, R5, R6 and R7 are benzoyl groups.

[0093] (Production Example 8) <Production of Compound (A): Benzylated Hemicellulose (n=3)> Benzylated hemicellulose (n=3) is produced in which the H moiety of the OH group of hemicellulose with n=3 is replaced with a benzyl group. This benzylated hemicellulose (n=3) was produced by the same method as that for benzylated xylose described in (Production Example 3).

[0094] In this benzylated hemicellulose (n=3), R1, R2, R5, and R6 are benzyl groups, and R4 is hydrogen.

[0095] (Production Example 9) <Production of Compound (A): Benzylated Cellulose (n=3)> Benzylated cellulose (n=3) is produced in which the H moiety of the OH group of cellulose (n=3) is replaced with a benzyl group. This benzylated cellulose (n=3) was produced by the same method as that for benzylated glucose described in Production Example 4.

[0096] (Production Example 10) <Production of Compound (A): Benzylated Starch (n=3)> Using benzylated starch, where the H part of the OH group of starch (n=3) has been replaced with a benzyl group, it is possible to produce bioplastic pellets with a biomass content of 5 to 70%. This benzylated starch is made up of R1, R2, R S , R6 and R7 are benzyl groups.

[0097] (Production Example 11) <Production of Compound (A): Benzoylated Hemicellulose (n=7)> As raw materials, a commercial mixture of xylose (n=1), hemicellulose (n=2), hemicellulose (n=3), hemicellulose (n=4), hemicellulose (n=5), hemicellulose (n=6) and hemicellulose (n=7) (hereinafter referred to as hemicellulose with n=7) was prepared. By adjusting the conditions for catalytic decomposition after extraction and purification from corn cobs, hemicellulose with n=7 (commercial product) can be obtained.

[0098] Benzoylated hemicellulose (n=7) is produced in which the H part of the OH group of hemicellulose with n=7 becomes a benzoyl group. This benzoylated hemicellulose (n=7) was produced by the same method as that for benzoylated xylose described in Production Example 1.

[0099] (Production Example 12) <Production of Compound (A): Benzoyl Cellulose (n=7)> A commercially available mixture of glucose (n=1), cellulose (n=2), cellulose (n=3), cellulose (n=4), cellulose (n=5), cellulose (n=6) and cellulose (n=7) (hereafter referred to as cellulose with n=7) was prepared as raw material. Cellulose with n=7 (commercial product) can be obtained by adjusting the conditions of catalytic decomposition after extraction and purification from trees.

[0100] Benzoylated cellulose (n=7) is produced in which the H moiety of the OH group of this cellulose (n=7) is replaced with a benzoyl group. This benzoylated cellulose (n=7) was produced by the same method as that for benzoylated glucose described in Production Example 2.

[0101] (Production Example 13) <Production of Compound (A): Benzoylated Starch (n=7)> As a raw material, a commercial mixture of glucose (n=1), starch (n=2), starch (n=3), starch (n=4), starch (n=5), starch (n=6) and starch (n=7) (hereinafter referred to as n=7 starch) may be used. Starch with n=7 (commercial product) can be obtained by adjusting the conditions of catalytic decomposition after extraction and purification from corn.

[0102] Benzoylated starch (n=7) is produced in which the H moiety of the OH group of starch with n=7 is replaced with a benzoyl group. This benzoylated starch (n=7) is produced by the same method as that for benzoylated glucose described in Production Example 2.

[0103] Using benzoylated starch (n=7) in which the H portion of the OH group of starch with n=7 has become a benzoyl group, bioplastic pellets with a biomass content of 5 to 70% can be produced in the same manner as in Production Example 12. In this benzoylated starch, R1, R2, R5, R6, and R7 are benzoyl groups.

[0104] (Production Example 14) <Production of Compound (A): Benzylated Hemicellulose (n=7)> Benzylated hemicellulose (n=7) is produced in which the H moiety of the OH group of hemicellulose with n=7 is replaced with a benzyl group. This benzylated hemicellulose (n=7) was produced by the same method as that for benzylated xylose described in Production Example 3.

[0105] In this benzylated hemicellulose (n=7), R1, R2, R5, and R6 are benzyl groups, and R4 is hydrogen.

[0106] (Production Example 15) <Production of Compound (A): Benzylated Cellulose (n=7)> Benzylated cellulose (n=7) is produced in which the H moiety of the OH group of cellulose (n=7) is replaced with a benzyl group. This benzylated cellulose (n=7) was produced by the same method as that for benzylated glucose described in Production Example 4.

[0107] In this benzylated cellulose (n=7), R1, R2, R5, R6 and R7 are benzyl groups.

[0108] The molecular weights of the compounds (A) in Production Examples 1 to 15 are shown in Table 1.

[0109] [Table 1]

[0110] Example 1 <Production of bioplastics> 150 g (5.0% by mass) of benzoyl xylose synthesized in Production Example 1 as compound (A) and 2850 g (95% by mass) of resin 1 shown in Table 2 were premixed using a tumbler. The premixed compound (A) and resin 1 were fed into a twin-screw kneading extruder (heating temperature 200°C) to obtain cylindrical pellets (φ3 mm). Various evaluations were performed using these pellets.

[0111] In Examples 2 to 31 and Reference Examples 1 and 2, the measurements and evaluations were carried out in the same manner as in Example 1, except that the blending amounts were changed as shown in Table 3.

[0112] The details of Resin 1 to Resin 9 are shown in Table 2, and the compositions, measurements and evaluation results of Examples 1 to 31 and Reference Examples 1 and 2 are shown in Tables 3 and 4.

[0113] [Table 2]

[0114] [Table 3]

[0115] [Table 4]

[0116] (Methods of measurement and evaluation) The measurements and evaluations were carried out according to the following methods.

[0117] <Weight average molecular weight measurement> Using a high-speed GPC HLC-8220 (manufactured by Tosoh Corporation) and columns (TSK-GELGMHXL x 2), a solution of 5 mg of sample dissolved in 10 g of THF was injected into the device (200 μL), and measurements were performed at a flow rate of 1 ml / min (THF), at a thermostatic bath temperature of 40°C, and with an RI detector.

[0118] <Injection processability> JIS K 7161 dumbbells were molded using a 100-ton injection molding machine and evaluated based on the following evaluation criteria. Easy container molding with no uneven thickness: ◎ Container molding is relatively easy and there is no uneven thickness: ○ Container molding is relatively easy, but there is uneven thickness: △ Difficult to mold containers and uneven thickness: ×

[0119] <Sheet film forming ability> A 40 mm sheet extruder was used to produce a sheet having a thickness of 250 μm. A die having a width of 40 cm was used, and the temperature was set to 200 to 230° C. The thickness controllability during film production and the appearance of the obtained sheet were confirmed, and evaluated based on the following evaluation criteria. Thickness control and appearance: Excellent Appearance: Good With roll transfer: △ The roll is hanging down from the sheet and cannot be wound up: ×

[0120] <Biaxial stretchability> The film was simultaneously biaxially stretched 1.5 times in the transverse direction and 1.5 times in the longitudinal direction using a single-shot stretching machine to obtain a stretched sheet of 110 μm, and then checked for thickness unevenness and thickness deviation. The stretching temperature was 110°C to 145°C, and the stretching speed was 120 mm / min. The film was evaluated based on the following criteria. Uniform thickness of sheet: ◎ Sheet without uneven thickness: 〇 Slight unevenness is seen: △ Uneven thickness or holes: ×

[0121] <Pneumatic formability> A container-shaped molded body was manufactured using a pressure molding machine. The container shape was 29 mm deep, with an opening of 80 mm x 80 mm, and a drawing ratio of 0.36. The molding was carried out by changing the hot plate temperature to find the optimal conditions for each sheet, which did not cause raindrop defects and provided good mold reproducibility. After that, it was evaluated based on the following evaluation criteria. The shape of the container is perfectly reproduced: Yes The model is not reproduced: ×

[0122] <Vacuum formability> After preparing an extrusion sheet using the styrene-based resin composition, secondary molding was performed into a container shape. The container was molded so that the ratio (H / W) of the depth (H) to the opening (W) was 0.3. The molding conditions were a preheating time of the sheet of 10 to 30 seconds, and a heater temperature of upper part / lower part=250 to 300°C / 250 to 300°C. Then, evaluation was performed based on the following evaluation criteria. The shape of the container is perfectly reproduced: Yes The shape of the container is not reproduced: ×

[0123] <Inflation film> The styrene resin composition and the rubber-reinforced styrene resin (HIPS) were mixed at a mixing ratio of 98 / 2 mass% using a twin-screw extruder (TEM26SS-12-2V) manufactured by Toshiba Machine Co., Ltd. at 200 ° C. and 150 rpm to obtain a styrene resin (I). Next, the obtained composition (I) was attached to the tip of a 20 mm extruder manufactured by Nakatani Machine Co., Ltd., a ring-shaped double cylinder was attached, and the resin coming out of the double cylinder was inflated and cooled, and taken up by a take-up machine to obtain an inflation film with a thickness of 25 μm for each example. A square with a side length of 10 cm was cut out from the center of the produced styrene film, and the thickness was measured at five points at 2 cm intervals perpendicular to the flow direction from a position 1 cm inside from the center in the flow direction, and the average thickness was calculated and evaluated based on the following evaluation criteria. The number of measurement points exceeding the average thickness by ±20% was less than 10% of all measurement points: ◎ The number of measurement points exceeding the average thickness by ±20% was 10-20% of all measurement points: ○ The number of measurement points exceeding the average thickness by ±20% was 20% or more of the total measurement points: ×

[0124] <Foaming> After preparing an extruded foam sheet using the styrene-based resin composition, secondary molding was performed into a container shape. The container was molded so that the ratio (H / W) of the depth (H) to the opening (W) was 0.2. The molding conditions were a preheating time of the foam sheet of 5 seconds, and the temperature of the heater was 280-300°C / 320-340°C (upper / lower), and the obtained container was evaluated based on the following evaluation criteria. The shape of the container is perfectly reproduced: ◎ Some types not reproduced: ○ A small hole appears on the edge of the bottom of the container: △ A large hole appears in the bottom of the container: ×

[0125] <hdt> From the styrene-based resin compositions obtained in the Examples and Comparative Examples, injection molded articles (80 mm×10 mm×4 mmT) were produced, and the deflection temperature under load (° C.) (flatwise, method A, load 1.80 MPa) was measured in accordance with JIS K 7191.

[0126] <Haze> An injection-molded plate having a thickness of 1 mm was prepared from the styrene-based resin composition obtained in each of the Examples and Comparative Examples, and the haze was measured in accordance with JIS K 7136.

[0127] <mfr> The MFR of the styrene-based resin compositions obtained in the examples and comparative examples was measured in accordance with JIS K7210 under the measurement conditions of 200°C and 5.0 kg.< / mfr> < / hdt>

Claims

1. A molded article of a thermoplastic bioplastic, The thermoplastic bioplastic contains a compound (A) represented by general formula (1) and a styrene-based resin, A molded article, wherein the content of the compound (A) is 0.1 to 70 mass % based on the total amount of the compound (A) and the styrene-based resin. 【Chemistry 1】 (In the formula, R １ is a substituent containing a benzene ring, R ２ is a substituent containing a benzene ring, R ３ is represented by the structural formula: R ６ A substituent represented by —O—, R ４ is hydrogen or the structural formula: R ７ -O-CH ２ A substituent represented by -, R ５ is a substituent containing a benzene ring, R ６ is a substituent containing a benzene ring, R ７ is a substituent containing a benzene ring. Also, n is an integer from 1 to 7.

2. The molded article according to claim 1, wherein the compound (A) has a molecular weight of 9,000 or less.

3. In the general formula (1), R １ , R ２ , R ３ , and R ５ are each independently a benzyl group or a benzoyl group; R ４ The molded article according to claim 1 or 2, wherein is hydrogen.

4. The molded article according to claim 1 or 2, which is a sheet-like molded article.

5. The molded article according to claim 4, which is a sheet-like molded article obtained by biaxially stretching the thermoplastic bioplastic.

6. The thickness is 0.5 to 6.0 mm and the bulk density is 0.02 to 0.25 g / cm ３ The molded article according to claim 4, which is a foamed sheet having a formula:

7. The molded article according to claim 6, which is obtained by molding the foamed sheet by a thermoforming method.

8. The molded article according to claim 1 or 2, which is a container.

9. The molded article according to claim 1 or 2, which is used for food packaging.

10. 3. A method for producing a molded article according to claim 1, comprising the step of melt-kneading and molding the compound (A) represented by the general formula (1) and the styrene-based resin.

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