Resin composition for thermal molding

Abstract

To provide a resin composition for thermal molding capable of preventing odor generation during heating in the molding process and producing an odor-free molded product.SOLUTION: A resin composition for thermal molding comprises a thermoplastic resin and zeolite particles (ZL) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less, the zeolite particles being contained in an amount of more than 0.1 wt.% and 15 wt.% or less based on the weight of the thermoplastic resin. It is preferable that the resin composition further contains plant-derived carbonized particles and / or zeolite particles (ZH) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) exceeding 8.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermoforming resin composition. [Background technology]

[0002] Widely used resin molded products are obtained by heating and melting thermoplastic resins and molding them. When heating and melting thermoplastic resins to mold them, they are heated to 180-220°C. Under such high temperature conditions, the thermoplastic resins and additives undergo thermal decomposition, producing volatile components, which not only cause odors during the molding process but also produce odors from residual components when the molded product is heated.

[0003] A resin composition containing recycled used plastic packaging containers containing polyolefin, zeolite, and a compatibilizer is known as a resin composition in which hydrocarbon volatiles generated by thermal degradation when a thermoplastic resin is heated are adsorbed onto zeolite (Patent Document 1). However, even the resin composition described in Patent Document 1 has a residual odor, and there is a demand for a resin composition with even less odor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2023-040503 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a thermoforming resin composition that does not give off an odor when heated at high temperatures during melt-kneading and molding of thermoplastic resins, or from resin molded articles. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems and have arrived at the present invention, which is a thermoforming resin composition comprising a thermoplastic resin and zeolite particles (ZL) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less, in an amount of more than 0.1 wt% and not more than 15 wt%, based on the weight of the thermoplastic resin. [Effects of the Invention]

[0007] The thermoforming resin composition of the present invention does not emit odors when heated at high temperatures during melt-kneading and molding, or from the resin molded product. DETAILED DESCRIPTION OF THE INVENTION

[0008] The first invention of the present application is a thermoforming resin composition (hereinafter referred to as the thermoforming resin composition of the present invention) containing a thermoplastic resin and zeolite particles (ZL) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less.

[0009] Examples of the thermoplastic resin contained in the thermoforming resin composition of the present invention include acrylic resin, polyester resin, polyacetal resin, polyolefin resin, styrene resin, polyamide resin, phenolic resin, and fluororesin, and may be recycled thermoplastic resin obtained by material recycling of recovered plastic products. Furthermore, examples of the thermoplastic resin contained in the thermoforming resin composition of the present invention include bioplastics such as polyvinyl alcohol resin for melt molding, polylactic acid resin made from starch contained in corn or the like, and composite bioplastics that are mixtures of plant-derived starch and the above-mentioned thermoplastic resins (such as rice resin that is a mixture with rice-derived starch). Furthermore, as the thermoplastic resin contained in the thermoforming resin composition of the present invention, one type of thermoplastic resin may be used alone, or two or more types of thermoplastic resins may be used in combination.

[0010] The thermoplastic resin contained in the thermoforming resin composition of the present invention is preferably a polyester resin (such as polyethylene terephthalate and polybutylene succinate) or a polyolefin resin (such as polyethylene, polypropylene, polybutene and polyisobutylene). Furthermore, the above-mentioned bioplastics and composite bioplastics can also be preferably used as the thermoplastic resin contained in the thermoforming resin composition of the present invention. Polypropylene includes random polypropylene, which is propylene copolymerized with a small amount of ethylene, and block polypropylene, which is polypropylene with ethylene propylene rubber (EPR), a rubber component, uniformly and finely dispersed in the polypropylene.

[0011] When the thermoplastic resin constituting the thermoforming resin composition is a polyolefin resin, the polyolefin resin preferably contains a polyolefin resin having a melt flow rate (MFR) of 1 to 50 (g / 10 min). When the thermoplastic resin is a polyolefin resin, it is preferable to further include a polyolefin resin having an MFR of 5 to 40, since this further improves the dispersibility of the zeolite particles (ZL) in the thermoforming resin composition and makes it easier to adsorb volatile components generated when the thermoplastic resin is heated. When the polyolefin is polypropylene, the MFR is a value measured in accordance with JIS K 6921-2, and when the polyolefin is polyethylene, the MFR is a value measured in accordance with JIS K 6922-1.

[0012] The thermoforming resin composition of the present invention contains zeolite particles (ZL) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less [hereinafter sometimes abbreviated as zeolite particles (ZL)]. The silica / alumina ratio refers to the ratio of silica to alumina contained in the chemical composition of the zeolite.

[0013] The zeolites constituting the zeolite particles (ZL) include natural zeolites and hydrophilic synthetic zeolites. Among the zeolites constituting the zeolite particles (ZL), examples of natural zeolites include Analcime (silica / alumina ratio = 2), Chabazite (silica / alumina ratio = 2.8 or less), Clinoptilolite (silica / alumina ratio = 2.7 to 5.3), Erionite (silica / alumina ratio = 3 to 4), Ferrierite (silica / alumina ratio = 3.2 to 6.2), Mordenite (silica / alumina ratio = 4.4 to 5.5), and Phillipsite (silica / alumina ratio = 2.9 or less). Among the zeolites that make up the zeolite particles (ZL), hydrophilic synthetic zeolites include A-type zeolite (silica / alumina ratio = 2), X-type zeolite (silica / alumina ratio = 2.5), Y-type zeolite (silica / alumina ratio = 4.8), ZK-4 zeolite (silica / alumina ratio = up to 3), and ZK-5 zeolite (silica / alumina ratio = 4 to 6).

[0014] The zeolite particles (ZL) are particles made of the above-mentioned zeolite, and there is no limitation on the shape of the particles, and zeolite particles having shapes such as irregular crushed shapes, spherical shapes, and pellet shapes can be used. Zeolite particles having a specific shape such as a spherical shape or a pellet shape are obtained by shaping zeolite powder obtained by pulverization or the like.

[0015] From the viewpoint of the mechanical properties of the molded article and odor reduction, the zeolite particles (ZL) preferably have a number average particle size of 2 to 100 μm, more preferably 5 to 50 μm. The particle size of the zeolite particles can be adjusted by pulverizing the zeolite as needed using a known method and classifying the zeolite using a known method such as sieving.

[0016] The thermoforming resin composition of the present invention may use two or more types of zeolite particles (ZL) in combination. It is preferable to use zeolite particles having a silica / alumina ratio of less than 4 in combination with zeolite particles having a silica / alumina ratio of 4 to 8, since this can further reduce the odor of the resin composition. When zeolite particles (ZL1) having a silica / alumina ratio of less than 4 are used in combination with zeolite particles (ZL2) having a silica / alumina ratio of 4 to 8, from the viewpoint of reducing the odor of the resin composition, the ratio of the weight content of zeolite particles (ZL1) to the weight content of zeolite particles (ZL2) [zeolite particles (ZL1) / zeolite particles (ZL2)] is preferably 20 / 80 to 80 / 20, and more preferably 30 / 70 to 55 / 45.

[0017] The total weight proportion of the zeolite particles (ZL) contained in the thermoforming resin composition of the present invention is more than 0.1 wt % and not more than 15 wt % based on the weight of the thermoplastic resin. If the weight proportion of the zeolite particles (ZL) is 0.1 wt % or less, odor adsorption is not possible, and if it exceeds 20 wt %, the mechanical properties of the molded product are deteriorated. The weight proportion of the zeolite particles (ZL) contained in the molding resin composition is preferably 0.2 to 15% by weight, more preferably 0.2 to 11% by weight, particularly preferably 0.5 to 8% by weight, and most preferably 1 to 7% by weight.

[0018] The thermoforming resin composition of the present invention preferably further contains plant-derived carbide particles and / or zeolite particles (ZH) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of more than 8. By including either or both of plant-derived carbide particles and zeolite particles (ZH) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of more than 8 [hereinafter abbreviated as zeolite particles (ZH)], odorous components that could not be adsorbed by zeolite particles (ZL) can be adsorbed by the plant-derived carbide particles and zeolite particles (ZH), which is preferable as it results in a resin composition with even less odor.

[0019] The plant-based carbonized particles that can be contained in the thermoforming resin composition of the present invention are carbonized materials obtained by carbonizing a plant-based organic raw material through heat treatment in a low-oxygen environment, and then pulverized into particles as necessary. They may be carbonized materials that have not been activated to produce activated carbon, or activated carbon obtained by activating them using a known method.

[0020] Preferred examples of plant-based organic raw materials include biomass such as grass and wood. Examples of biomass obtained from wood include pruned branches and thinned wood from broad-leaved and coniferous trees, while examples of biomass obtained from grasses include pruned branches and thinned wood from bamboo, rice husks, soybean husks, corn cobs, plant stalks, and grass clippings. In addition, wood chips, bark, sawdust, shavings, etc. generated during wood processing can also be preferably used as plant-based organic raw materials. The heat treatment of the plant-based organic raw material can be carried out using known carbonization equipment such as a charcoal kiln or a carbonization furnace, and the resulting charcoal can be pulverized as needed to obtain plant-based charcoal particles. The charcoal can be pulverized using known pulverizers such as a ball mill, rod mill, bead mill, conical mill, disk mill, edge mill, hammer mill, mortar, pellet mill, VSI mill, Willy mill, roller mill, jet mill, and mass colloider.

[0021] The plant-derived carbide particles preferably have a number-average particle size of 1 to 100 μm, more preferably 5 to 50 μm, which is preferable because this range makes it easier to adsorb volatile components generated when a thermoplastic resin is heated.

[0022] The zeolite particles (ZH) that can be contained in the thermoforming resin composition of the present invention include particles made of ZSM-5 type zeolite (silica / alumina ratio = 69 to 93) and ZSM-11 type zeolite (silica / alumina ratio = 80 to 93). As the zeolite particles (ZH), commercially available zeolite particles such as HSZ-980HOA, HSZ-890HOA, HSZ-891HOA, HSZ-690HOA, HSZ-385HUA and HSZ-390HUA (all synthetic zeolites manufactured by Tosoh Corporation) can also be preferably used.

[0023] The zeolite particles (ZH) can be zeolite particles having shapes such as irregular crushed shapes, spheres, pellets, etc. Zeolite particles having specific shapes such as spheres and pellets are obtained by molding zeolite powder obtained by pulverization or the like.

[0024] The zeolite particles (ZH) preferably have a number average particle size of 2 to 100 μm, more preferably 5 to 50 μm, from the viewpoint of facilitating adsorption of volatile components generated when a thermoplastic resin is heated.

[0025] When the thermoforming resin composition of the present invention further contains plant-based carbonized particles and / or zeolite particles (ZH), the ratio of the total weight of the plant-based carbonized particles and zeolite particles (ZH) to the weight of the zeolite particles (ZL) [(total weight of the plant-based carbonized particles and zeolite particles (ZH)) / weight of the zeolite particles (ZL)] can be adjusted depending on the polarity of the odor components generated when the thermoplastic resin is heated.

[0026] In the case where highly polar odorous components are generated when the thermoforming resin composition is heated, the ratio of the total weight of the plant-based carbonized particles and the zeolite particles (ZH) to the weight of the zeolite particles (ZL) [(total weight of the plant-based carbonized particles and the zeolite particles (ZH)) / weight of the zeolite particles (ZL)] is preferably 10 / 90 to 40 / 60, and more preferably 10 / 90 to 20 / 80. Thermoplastic resins that generate highly polar odorous components include polyester resins, polyacetal resins, etc. In addition, when a thermoforming resin composition contains biomass powder such as wood flour as a filler, highly polar odorous components are also generated. Highly polar odorous components emitted from these resins include aldehyde compounds (acetaldehyde, benzaldehyde, etc.), acid compounds (acetic acid, isovaleric acid, etc.), amine compounds (trimethylamine, etc.), and heteroaromatic ring compounds (furfural, pyrrole, etc.).

[0027] In the case where odorous components with low polarity are generated when the thermoforming resin composition is heated, the ratio of the total weight of the plant-based carbonized particles and the zeolite particles (ZH) to the weight of the zeolite particles (ZL) [(total weight of the plant-based carbonized particles and the zeolite particles (ZH)) / weight of the zeolite particles (ZL)] is preferably 40 / 60 to 20 / 80, and more preferably 60 / 40 to 20 / 80. Thermoplastic resins that generate odorous components with low polarity include polyolefin resins, polystyrene resins, polyacrylic resins, etc. In addition, when recycled thermoplastic resins obtained by material recycling from plastic products recovered as thermoforming thermoplastic resins are used, odorous components with low polarity are also generated. Low polarity odor components emitted from these resins include alkenes (1,3-butadiene, etc.) and aromatic ring compounds (toluene, xylene, styrene, etc.).

[0028] The thermoforming resin composition of the present invention may contain other additives such as colorants, mold release agents, antioxidants, flame retardants, ultraviolet absorbers, antibacterial agents, and fillers.

[0029] Examples of colorants include inorganic pigments (white pigments, cobalt compounds, iron compounds, sulfides, etc.), organic pigments (azo pigments, polycyclic pigments, etc.), and dyes (azo-based, indigoid-based, sulfide-based, alizarin-based, acridine-based, thiazole-based, nitro-based, aniline-based, etc.).

[0030] Examples of the release agent include lower alcohol esters (having 1 to 4 carbon atoms) of higher fatty acids (butyl stearate, etc.), polyhydric (dihydric to tetrahydric or higher) alcohol esters (having 2 to 18 carbon atoms) of fatty acids (having 2 to 18 carbon atoms) (hydrogenated castor oil, etc.), glycol (having 2 to 8 carbon atoms) esters (ethylene glycol monostearate, etc.) of fatty acids (having 2 to 18 carbon atoms), and liquid paraffin.

[0031] As the antioxidant, known antioxidants can be used, and preferred antioxidants include hindered phenol-based antioxidants and phosphoric acid-based antioxidants. Examples of hindered phenol antioxidants include pentaerythrityl tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], triethylene glycol bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate, octadecyl-3-(3,5-di-butyl-4-hydroxyphenyl)propionate], and of these, pentaerythrityl tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate] is preferred. Examples of phosphorus-based antioxidants include tris(2,4-di-t-butylphenyl)phosphite, triphenyl phosphite, and bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol-diphosphite, and of these, tris(2,4-di-t-butylphenyl)phosphite is preferred.

[0032] Examples of the flame retardant include halogen-containing flame retardants, nitrogen-containing flame retardants, sulfur-containing flame retardants, silicon-containing flame retardants, and phosphorus-containing flame retardants.

[0033] Examples of ultraviolet absorbers include benzotriazoles (such as 2-(2'-hydroxy-5'-methylphenyl)benzotriazole), benzophenones (such as 2-hydroxy-4-methoxybenzophenone), salicylates (such as phenyl salicylate), and acrylates (such as 2-ethylhexyl-2-cyano-3,3-diphenylacrylate).

[0034] Antibacterial agents include benzoic acid, sorbic acid, halogenated phenols, organic iodines, nitriles (such as 2,4,5,6-tetrachloroisophthalonitrile), thiocyano (methylenebisthianocyanate), N-haloalkylthioimides, copper agents (such as 8-oxyquinoline copper), benzimidazole, benzothiazole, trihaloallyl, triazole, organic nitrogen-sulfur compounds (such as Slaof 39), quaternary ammonium compounds, and pyridine-based compounds.

[0035] Examples of fillers include inorganic fillers such as kaolin, talc, silica, titanium oxide, calcium carbonate, bentonite, mica, sericite, glass flakes, glass fiber, graphite, magnesium hydroxide, aluminum hydroxide, antimony trioxide, barium sulfate, zinc borate, alumina, magnesia, wollastonite, xonotlite, whiskers, and metal powder, as well as organic fillers such as cellulose fiber, animal fiber, wood flour, wood chips, eggshell powder, shell powder, crustacean exoskeleton powder, and thermosetting bridged resin particles (epoxy resin particles, etc.).

[0036] The type and content of other additives that the thermoforming resin composition may further contain can be selected depending on the use of the molding resin composition, the type of thermoplastic resin that constitutes the molding resin composition, etc. In particular, when the thermoforming resin composition contains biomass powder as a filler (a filler derived from organic resources obtained from plants and animals, such as cellulose fiber, animal fiber, wood flour, wood chips, eggshell powder, shell powder, and crustacean exoskeleton powder), or when the above-mentioned bioplastics and composite bioplastics are used as the thermoplastic resin, it is preferable that the thermoforming resin composition contain 0.05 to 5 wt % of an antioxidant, and more preferably 0.1 to 2 wt % of an antioxidant, based on the total weight of the thermoforming resin composition, from the viewpoints of odor and mechanical properties of the molded product.

[0037] The thermoforming resin composition of the present invention can be obtained by melt-kneading a thermoplastic resin and zeolite particles (ZL), as well as plant-derived carbide particles, zeolite particles (ZH), and other additives used as needed, by a known method. An applicable method is to mix pelletized or powdered raw materials in a known powder mixer (e.g., a Henschel mixer), and then heat, melt, and mix them in a melt kneader (e.g., a twin-screw extruder) to form pellets, etc.

[0038] There are no restrictions on the order in which the raw materials are added when melt-kneading the thermoplastic resin and zeolite particles (ZL), as well as the plant-derived carbide particles, zeolite particles (ZH), and other additives used as needed. Methods that can be applied include melt-kneading the zeolite particles (ZL) into a thermoplastic resin (preferably a polyolefin resin) at a high concentration (preferably 30 to 600 wt % of the zeolite particles (ZL) based on the weight of the thermoplastic resin) to prepare a masterbatch, and then further mixing and melt-kneading the prepared masterbatch with the remaining thermoplastic resin, the acid-modified polyolefin used as needed, and other additives (Method 1), and melt-kneading all the raw materials at once (Method 2).

[0039] As a method for obtaining the thermoforming resin composition of the present invention by mixing a thermoplastic resin and zeolite particles (ZL), the above-mentioned method 1 is preferred. The thermoplastic resin used in the masterbatch preferably has a melt flow rate (also referred to as MFR) of 10 to 50 (g / 10 min). When the MFR is in this range, the dispersibility of the zeolite particles in the thermoforming resin composition is favorable, which is preferable. When the polyolefin is polypropylene, the MFR is a value measured in accordance with JIS K 6921-2, and when the polyolefin is polyethylene, the MFR is a value measured in accordance with JIS K 6922-1.

[0040] The thermoplastic resin used in the masterbatch is more preferably a polyolefin resin with a melt float of 20 to 50 (g / 10 min), and particularly preferably a polyethylene with a melt flow rate of 20 to 50 (g / 10 min) or a polypropylene with a melt float of 20 to 50 (g / 10 min). When the polyolefin is polypropylene, the MFR is a value measured in accordance with JIS K 6921-2, and when the polyolefin is polyethylene, the MFR is a value measured in accordance with JIS K 6922-1.

[0041] A second invention of the present application is a masterbatch composition (hereinafter referred to as the masterbatch composition of the present invention) containing a polyolefin resin having a melt flow rate (MFR) of 20 to 50 (g / 10 min) and zeolite particles (ZL) having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less. The masterbatch composition of the present invention is preferably a masterbatch composition for a thermoforming resin composition. By using the masterbatch composition of the present invention to produce the thermoforming resin composition, the dispersibility of the zeolite particles (ZL) in the thermoforming resin composition is improved, and the adsorption of volatile components generated when a thermoplastic resin is heated and the mechanical properties are improved, which is preferable.

[0042] The polyolefin resin used in the masterbatch composition is preferably polyethylene having a melt flow rate of 20 to 50 (g / 10 min) or polypropylene having a melt flow rate of 20 to 50 (g / 10 min). When the polyolefin is polypropylene, the MFR is a value measured in accordance with JIS K 6921-2, and when the polyolefin is polyethylene, the MFR is a value measured in accordance with JIS K 6922-1.

[0043] The weight proportion of the zeolite particles (ZL) in the masterbatch composition of the present invention is preferably 20 to 90% by weight relative to the total weight of the masterbatch composition.

[0044] The masterbatch composition of the present invention preferably further contains the above-mentioned zeolite (ZH) and plant-based carbide particles (P), and the ratio of the total weight of the plant-based carbide particles and zeolite particles (ZH) to the weight of the zeolite particles (ZL) [(total weight of the plant-based carbide particles and zeolite particles (ZH)) / weight of the zeolite particles (ZL)] is preferably 10 / 90 to 40 / 60, and more preferably 10 / 90 to 20 / 80.

[0045] The masterbatch of the present invention can be obtained by melt-kneading a thermoplastic resin and zeolite particles (ZL), as well as plant-derived carbide particles, zeolite particles (ZH), and other additives used as needed, using a known method. An applicable method is to mix the raw materials in a known powder mixer (such as a Henschel mixer), and then heat, melt, and mix them in a melt kneader (such as a twin-screw extruder), followed by pelletization, etc.

[0046] The temperature and kneading time when melt-kneading to obtain the masterbatch composition and thermoforming resin composition of the present invention can be adjusted depending on the type of thermoplastic resin. When a polyethylene resin is used as the thermoplastic resin, the kneading temperature is preferably 130 to 230°C, and when a polypropylene resin is used, the kneading temperature is preferably 160 to 260°C.

[0047] The thermoforming resin composition of the present invention obtained by melt kneading may be extruded in the form of a strand from an extruder, cooled with a belt cooler or the like, and then cut and molded into pellets, or may be pulverized into powder or granules by a known method.

[0048] The thermoforming resin composition of the present invention can be molded using known molding methods such as injection molding, compression molding, calendar molding, slush molding, rotational molding, extrusion molding, blow molding, and film molding (casting method, tenter method, inflation method, etc.), and single-layer molding, multi-layer molding, foam molding, etc. are also possible depending on the purpose. [Example]

[0049] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0050] <Production Example 1> 2.0 parts by weight of acid-modified polyolefin Umex 1010 (Sanyo Chemical Industries, Ltd.), 50.0 parts by weight of thermoplastic polyethylene resin (product name: UBE Polyethylene LDPE F222NH, MFR (JIS K7210-1) = 2, Ube Maruzen Polyethylene Co., Ltd.), 40 parts by weight of starch (derived from wheat flour, Fujifilm Wako Pure Chemical Industries, Ltd.), and 10 parts by weight of D-sorbitol were placed in a polypropylene beaker and premixed by gently stirring with a stirring blade. The mixture was then kneaded for 10 minutes using a Labo Plastomill (a kneading and extrudability testing device manufactured by Toyo Seiki Seisaku-sho, Ltd.) at a chamber temperature of 200°C and a mixer rotation speed of 60 rpm to obtain a composite bioplastic composed of starch and polyethylene.

[0051] <Production Example 2> Underfloor humidity-regulating charcoal Plus-1 (powder) (manufactured by Nara Carbonization Co., Ltd.) was pulverized in a ball mill and then classified using a high-precision electroplated sieve (opening size 10 μm). The fine powder that passed through the sieve was collected and used as the plant-based charcoal particles (P-1) used in this example.

[0052] <Examples 1 to 13, Comparative Example 1> The zeolite particles (ZL), zeolite particles (ZH), plant-derived carbonized particles (P), acid-modified polyolefin resin (B), and antioxidant (C) listed in Table 1 were placed in a polypropylene beaker and premixed by gently stirring with a stirring blade. In Examples 1 to 8 and Comparative Example 1, the thermoplastic resin (A1) in the number of parts listed in Table 1 was added to the kneading section of a Labo Plastomill (a kneading and extrudability testing device manufactured by Toyo Seiki Seisaku-sho, Ltd.) whose temperature was adjusted to 160°C, and in Production Examples 9 to 13, the thermoplastic resin (A2) in the number of parts listed in Table 1 was added to the kneading section of a Labo Plastomill whose temperature was adjusted to 220°C. After mixing for 1 minute at a stirring section rotation speed of 10 rpm, a mixture that had been premixed in a polypropylene beaker was further added to the kneading section and further mixed for 10 minutes at a stirring section rotation speed of 60 rpm. The mixture was removed from the Laboplastomill and molded to a thickness of 2 mm using a pressure molding machine whose temperature was adjusted to 160°C for Production Examples 1 to 8 and Comparative Example 1, and to 220°C for Production Examples 9 to 13.Then, the mixture was cut using a pelletizer to obtain masterbatch pellets (MB1 to MB13, MBH1) for Production Examples 3 to 15 and Comparative Production Example 1. The weights of the thermoplastic resin (A), zeolite (ZL), zeolite (ZH), plant-derived carbonized particles (P), acid-modified polyolefin (B), and antioxidant (C) used in Production Examples 1 to 13 and Comparative Example 1 were in accordance with the weight parts shown in Table 1. In Table 1, blank spaces indicate that the corresponding component was not used.

[0053] [Table 1]

[0054] In Examples 1 to 13 and Comparative Example 1, the following thermoplastic resin (A), zeolite (ZL), zeolite (ZH), plant-derived carbonized particles (P), acid-modified polyolefin (B), and antioxidant (C) were used.

[0055] <Thermoplastic resin (A)> Thermoplastic resin (A-1): Low-density polyethylene manufactured by Ube Maruzen Polyethylene Co., Ltd., product name: J2522, MFR = 20 (conditions: 190°C, 2.16 kg) Thermoplastic resin (A-2): Injection molding block polypropylene manufactured by SunAllomer Co., Ltd., trade name: SunAllomer PM970A, MFR = 30 (conditions: 230°C, 2.16 kg)

[0056] <Zeolite (ZL)> Zeolite (ZL-1): Synthetic zeolite powder with a silica / alumina ratio of 2.5, product name: Molecular Sieve 13X Powder, manufactured by Resonac Universal Co., Ltd. Zeolite (ZL-2): Synthetic zeolite powder with a silica / alumina ratio of 5.5, product name: HS-320 powder, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Zeolite (ZL-3): Synthetic zeolite powder with a silica / alumina ratio of 7, product name: HS-341 powder, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Zeolite (ZL-4): Synthetic zeolite powder with a silica / alumina ratio of 6.1, product name: HS-500, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Zeolite (ZL-5): Natural zeolite powder with a silica / alumina ratio of 5, product name: SP#600, manufactured by Nitto Funka Kogyo Co., Ltd.

[0057] <Zeolite (ZH)> Zeolite (ZH-1): Synthetic zeolite powder with a silica / alumina ratio of 18, product name: HS642, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Zeolite (ZH-2): Synthetic zeolite powder with a silica / alumina ratio of 40, product name: HSZ-840HOA, manufactured by Tosoh Corporation

[0058] <Plant-based carbide particles (P)> Plant-based charcoal particles (P-1): charcoal powder obtained in Production Example 2 ·Plant-based carbide particles (P-2): Activated carbon (manufactured by Futamura Chemical Co., Ltd., product name: P (powder activated carbon) average particle size 30 μm)

[0059] <Acid-modified polyolefin (B)> Acid-modified polyolefin (B-1): Product name: Umex 1001, manufactured by Sanyo Chemical Industries, Ltd.

[0060] <Antioxidant (C)> Antioxidant (C-1): Trade name: Irganox 1010, a hindered phenolic antioxidant manufactured by BASF Japan Ltd. Antioxidant (C-2): Trade name: Irganox 1076, a hindered phenolic antioxidant manufactured by BASF Japan Ltd. Antioxidant (C-3): Trade name: Irgafos 168, a phosphorus-based antioxidant manufactured by BASF Japan Ltd.

[0061] <Examples 14 to 31 and Comparative Examples 2 to 6> The thermoplastic resin (S) shown in Table 2 and the masterbatch pellets (MB) obtained in Examples 1 to 13 and Comparative Example 1 were blended for 3 minutes in a Henschel mixer, and then melt-kneaded at 200 rpm and a residence time of 5 minutes using a vented twin-screw extruder adjusted to the temperature shown in Table 2. The mixture was then cut into pellets using a pelletizer to obtain thermoforming resin compositions (X) according to Examples 14 to 31 and Comparative Examples 2 to 6. The weights of the thermoplastic resin and masterbatch pellets were in accordance with the weights (unit: parts by weight) shown in Table 2. In Table 2, blank spaces indicate that the corresponding component was not used.

[0062] Example 32 Using a vented twin-screw extruder adjusted to the temperature shown in Table 2, the thermoplastic resin (S) shown in Table 2 was melt-kneaded at 200 rpm for a residence time of 5 minutes while adding zeolite (ZL) from the vent using a side feeder, and then cut into pellets using a pelletizer to obtain a thermoforming resin composition (X) according to Example 32. The weights of the thermoplastic resin and zeolite (ZL) were in accordance with the weights (unit: parts by weight) shown in Table 2. In Table 2, blank spaces indicate that the corresponding component was not used.

[0063] [Table 2]

[0064] In Examples 14 to 32 and Comparative Examples 2 to 6, the following thermoplastic resins were used.

[0065] <Thermoplastic resin> Thermoplastic resin (S-1): Composite bioplastic obtained in Production Example 1 Thermoplastic resin (S-2): Recycled polypropylene (product name: TPC-PPC05 / 2, manufactured by Teamplas Chemical)

[0066] For the thermoforming resin compositions obtained in Examples 14 to 32 and Comparative Examples 2 to 6, the odor of the molded article and the odor of the heated molded article were evaluated by the following method, and the results are shown in Table 3.

[0067] <Odor of molded products> The thermoforming resin compositions of the present invention obtained in Examples 14 to 32 and the comparative thermoforming resin compositions obtained in Comparative Examples 2 to 6 were each heat-molded into a 10 mm thick plate using a pressure molding machine adjusted to 180°C for the thermoforming resin compositions obtained in Examples 14 to 23, 30 and Comparative Examples 2 to 4, or using a pressure molding machine adjusted to 200°C for the thermoforming resin compositions obtained in Examples 24 to 29, 31, 32 and Comparative Examples 5 to 6.Then, the plates were cut into 100 mm x 100 mm x 10 mm pieces to obtain test molded specimens of the thermoforming resin compositions obtained in each Example and Comparative Example. The test molded product was placed in a 2 L glass desiccator, the lid was put on and the desiccator was left standing at 40°C. After 24 hours of standing, the lid was slightly opened and the odor was confirmed by smelling the desiccated product. The perceived odor intensity was rated on a 5-point scale ranging from odor intensity 0 (no odor) to odor intensity 4 (strong odor). <Odor intensity> Odor intensity 0: Odorless Odor intensity 1: barely detectable odor Odor intensity 2: Weak odor Odor intensity 3: Easily detectable odor Odor intensity 4: Strong odor

[0068] <Amount of odor-causing substances emitted from heated molded products> For each test molded product of the thermoforming resin composition of the present invention obtained in Examples 14 to 32 and the comparative thermoforming resin composition obtained in Comparative Examples 2 to 6, it was cryogenically pulverized using a small-scale cryogenic pulverizer (pre-cooling time of 10 minutes under liquid nitrogen, pulverization time of 20 minutes). Approximately 10 mg of the pulverized sample was weighed and placed in a TENAX tube, set in a thermal decomposition gas chromatography (TD-GC / MS), and the measurement of odor-causing substances generated when the molded product was heated was carried out under the following measurement conditions. As a reference sample, only the thermoplastic resin used in each example and comparative example was kneaded with a lab plastomill in the same manner as in each example and comparative example, and further thermoformed to prepare a test molded product not containing zeolite. Similarly, the measurement of odor-causing substances generated when the molded product was heated was carried out using thermal decomposition gas chromatography under the following measurement conditions. The peak area of each measured odor-causing substance was divided by the weight (mg) of the sample placed in the TENAX tube to calculate the area per 1 mg of the sample, and it was converted to a relative value when the area of the odor-causing substance in 1 mg of the test molded product not containing zeolite was set to 100, and the amounts of odor-causing substances generated by heating the thermoforming resin compositions according to Examples 14 to 32 and Comparative Examples 2 to 6 are shown in Table 3. Acetaldehyde, acetic acid, and hexadecane measured by thermal decomposition gas chromatography are odor-causing substances generated by the oxidative decomposition of glucose in thermoplastic resins and starch. It can be said that less generation of these chemical substances means less odor generation. <TD-GC / MS Measurement Conditions> GC Conditions · Apparatus: GCMS-TQ8040 [manufactured by Shimadzu Corporation] · Column: ZB-WAX (length: 30 m, inner diameter: 0.25 mm, film thickness: 0.25 μm) · Inlet pressure: 100 kPa · Split ratio: 10 · Temperature program: Hold at 40 °C for 5 minutes, then raise the temperature to 230 °C, hold at 230 °C for 10 minutes, heating rate: 10 °C / min MS Conditions · Ionization mode: EI · Detection mode: Scan (m / z = 33 - 300) Detector voltage (relative): 0kV Tuning voltage: 1.09kV

[0069] <Mechanical properties (tensile strength)> Each of the thermoforming resin compositions (X) according to Examples 14 to 32 and Comparative Examples 2 to 6 was molded using an injection molding machine (PS40E5ASE, manufactured by Nissei Plastic Industrial Co., Ltd.) at a cylinder temperature of 210°C and a mold temperature of 60°C to prepare test pieces (JIS K7127, test piece type B1) for evaluating tensile strength. The tensile strength of the prepared test piece was measured at a tension speed of 50 mm / min in accordance with JIS K7127. Measurement was carried out five times for each thermoforming resin composition (X), and the average values ​​are shown in Table 3.

[0070] [Table 3]

[0071] The thermoforming resin composition of the present invention, which contains zeolite particles having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of 2 or more and 8 or less, generates less odor and has a wider variety of compounds that can prevent odor generation when heated, compared to a comparative thermoforming resin composition containing only zeolite having a silica / alumina ratio (SiO2 / Al2O3 molar ratio) of more than 8. This shows that the thermoforming resin composition of the present invention generates less odor when heated during molding, etc., and from the molded product, compared to conventional methods. [Industrial Applicability]

[0072] The thermoforming resin composition of the present invention is suitable for resin molded articles used in our daily lives, such as daily necessities and electrical appliances, as well as resin molded articles used in enclosed spaces, such as the interior of an automobile, because no odor-causing chemical substances are detected in the thermoforming resin composition even when heated, and odor-free molded articles can be obtained. This is particularly useful when bioplastics and recycled thermoplastic resins, which tend to generate odors, are used as thermoplastic resins.

Claims

1. a thermoplastic resin and a silica / alumina ratio (SiO) of greater than 0.1 wt. % and not greater than 15 wt. % based on the weight of said thermoplastic resin; ２ / Al ２ O ３ A thermoforming resin composition comprising zeolite particles (ZL) having a molar ratio of 2 to 8.

2. 2. The thermoforming resin composition according to claim 1, wherein the thermoplastic resin is a polyolefin resin.

3. 3. The thermoforming resin composition according to claim 2, which contains a polyolefin resin having a melt flow rate (MFR) of 20 to 50 (g / 10 min).

4. Plant-based carbide particles and / or silica / alumina ratio (SiO ２ / Al ２ O ３ The thermoforming resin composition according to any one of claims 1 to 3, further comprising zeolite particles (ZH) having a molar ratio (molar ratio) of more than 8.

5. A polyolefin resin having a melt flow rate (MFR) of 20 to 50 (g / 10 min) and a silica / alumina ratio (SiO ２ / Al ２ O ３ and zeolite particles (ZL) having a molar ratio of 2 to 8.

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