Resin composition for molding

Abstract

This resin composition for molding contains plant-based carbide particles, an acid-modified polyolefin resin, and a thermoplastic resin other than the acid-modified polyolefin resin. The total acidic functional group content of the plant-based carbide particles according to an acid-base neutralization titration method is 0.02-1.0 mmol / g, the total basic functional group content is 0.3-1.9 mmol / g, and the acid value of the acid-modified polyolefin resin is 3-40 mg KOH / g.

Description

Molding resin composition

[0001] The present invention relates to a molding resin composition.

[0002] There is a growing social need for resource conservation and material recycling, which reuses waste as raw materials, and biomass materials derived from living organisms such as plants, such as woody biomass materials, and recycled plastics, which are material recycling materials, are attracting attention as industrial resources. Furthermore, blending woody biomass materials into widely used resin molded products has been studied (Patent Document 1).

[0003] Resin molded products are obtained by heating thermoplastic resins to 180 to 220°C, melting them, and molding them. However, the high temperatures experienced when heating and melting thermoplastic resins can cause the thermoplastic resins and additives to thermally decompose, producing volatile components that can cause odors during molding or that can remain in the molded products.

[0004] A molding resin material containing pulverized woody biomass carbonized material with an average particle size of 100 μm or less and a thermoplastic resin is known as a molding resin material that produces less odor during molding (Patent Document 2).

[0005] JP 2010-138337 A JP 2023-149385 A

[0006] However, the resin material described in Patent Document 2 is unable to sufficiently suppress the evaporation of highly polar components among the volatile components generated when heated and melted, and is therefore unable to sufficiently reduce odors generated during molding processing and the odor of molded products.

[0007] An object of the present invention is to provide a molding resin composition which can give a molded article having a low odor, and which generates a small amount of odor even when heated at high temperatures.

[0008] The present inventors conducted extensive research to solve the above problems and arrived at the present invention. Specifically, the present invention provides a molding resin composition comprising plant-derived carbonized particles, an acid-modified polyolefin resin, and a thermoplastic resin other than the acid-modified polyolefin resin, wherein the plant-derived carbonized particles have a total acidic functional group content of 0.02 to 1.0 mmol / g and a total basic functional group content of 0.3 to 1.9 mmol / g, as measured by acid-base neutralization titration, and the acid-modified polyolefin resin has an acid value of 3 to 40 mgKOH / g.

[0009] The molding resin composition of the present invention can give molded articles that emit little odor even when heated at high temperatures.

[0010] The molding resin composition of the present invention contains plant-derived carbonized particles, an acid-modified polyolefin resin, and a thermoplastic resin other than the acid-modified polyolefin resin.

[0011] The plant-derived charcoal particles of the present invention are not particularly limited as long as they have a total acidic functional group content of 0.02 to 1.0 mmol / g and a total basic functional group content of 0.3 to 1.9 mmol / g, as determined by acid-base neutralization titration. Examples of plant-derived charcoal particles that can be used include charcoal obtained by carbonizing raw plant biomass through heat treatment in a low-oxygen environment. If necessary, charcoal obtained by further pulverizing the raw material into particles or by further activating the particles may also be used.

[0012] Examples of plant biomass that can be used include wood, grasses, seed husks, peat, etc. Examples of wood include broad-leaved trees (eucalyptus, rubber tree, beech, Chinese linden, white birch, poplar, acacia, oak, sugar maple, Asiatic ash, elm, paulownia, magnolia, willow, ash, phillyraeoides phillyraeoides, oak, sawtooth oak, horse chestnut, zelkova, beech, dogwood, and ash tree, etc.), and coniferous trees (cedar, spruce, larch, Japanese black pine, Abies sachalinensis, Japanese yew, juniper, spruce, Japanese holly, Japanese holly, fir, Japanese sawara, Dogasawara, Asunaro, Japanese cypress, Japanese cedar, Tsuga, Japanese hemlock, Japanese cypress, Japanese yew, Japanese yew, spruce, yellow cedar, and Japanese cypress, etc.). Examples of grasses include stems and leaves of grains (rice, beans, corn, etc.), bamboo, etc. Examples of seed husks include rice husks, soybean husks, coconut shells, etc. Among these, seed husks are preferred, and coconut shells are more preferred, from the viewpoint of the adsorption effect of volatile components, etc. One type of plant biomass may be used alone, or two or more types may be used in combination.

[0013] Carbonized plant biomass can be obtained by heating it to 400 to 1200°C (preferably 600 to 1200°C, more preferably 600 to 1100°C) in a low-oxygen environment (preferably an oxygen concentration of 10% or less). The carbonization apparatus is not particularly limited, and known carbonization apparatuses such as rotary kilns and vertical furnaces can be used.

[0014] There are no limitations on the shape of the plant biomass raw material, and preferred are wood chips, bark, sawdust, sawdust, and materials adjusted to a size of preferably 50 mm or less by crushing, etc. Known crushers such as hammer mills and knife-cutting chippers can be used to crush the plant biomass, and a known sieving machine can be used to adjust the size after crushing.

[0015] When further activation is performed after carbonization of plant biomass, the activation treatment can be carried out in the same manner as known activation treatments (gas activation method, chemical activation method, etc.).

[0016] The total acidic functional group content of the plant-derived carbonized particles is 0.02 to 1.0 mmol / g, preferably 0.05 to 0.7 mmol / g, and more preferably 0.05 to 0.5 mmol / g. If the total acidic functional group content is less than 0.02 mmol / g, the volatilization of highly polar components (acetaldehyde, acetic acid, etc.) cannot be sufficiently suppressed, while if it exceeds 1.0 mmol / g, the thermal decomposition of the thermoplastic resin is accelerated, resulting in an increase in the amount of odorous components generated and a deterioration in the physical properties of the molded product. The total acidic functional group content is a value determined by acid-base neutralization titration using the Boehm method (H.P. Boehm, Adv. Catal., 16, 179 (1966)). The total acidic functional group content can be calculated by adding sodium hydroxide or sodium alkoxide (sodium ethoxide, etc.) as an alkaline component to an aqueous dispersion of plant-derived carbonized particles to neutralize the acidic functional groups of the plant-derived carbonized particles, then performing neutralization titration using a hydrochloric acid standard solution to determine the amount of alkaline component that did not react with the sample.

[0017] The total basic functional group content of the plant-derived carbonized particles is 0.3 to 1.9 mmol / g, preferably 0.4 to 1.4 mmol / g, and more preferably 0.5 to 1.3 mmol / g. A total basic functional group content of less than 0.3 mmol / g fails to sufficiently suppress the volatilization of highly polar components, while a total basic functional group content of more than 1.9 mmol / g reduces adhesion between the plant-derived carbonized particles and the resin, resulting in reduced strength of the molded product. The total basic functional group content is determined by acid-base neutralization titration using the Boehm method (see H.P. Boehm, Adv. Catal., 16, 179 (1966)). This can be calculated by adding hydrochloric acid as an acid component to an aqueous dispersion of the plant-derived carbonized particles to neutralize the basic functional groups of the plant-derived carbonized particles, followed by neutralization titration with a sodium hydroxide standard solution to determine the amount of hydrochloric acid that did not react with the sample.

[0018] The total acidic functional group content and total basic functional group content of the plant-based carbonized particles can be adjusted to a predetermined range by adjusting the type of material to be carbonized, the heating conditions during the carbonization treatment, the activation treatment conditions, etc.

[0019] The plant-based carbide particles preferably have a number-average particle size of 5 to 100 μm, more preferably 5 to 50 μm. A number-average particle size of 5 to 100 μm is preferred because it tends to further reduce the amount of odor generated during heating during molding. In this specification, the number-average particle size and maximum particle size are values ​​obtained by the following method: An image containing projected images of 500 particles is acquired, and the diameter of a circle with an area equal to the area of ​​each particle in the image is calculated. The calculation results are plotted on a graph with particle size on the horizontal axis and cumulative frequency of particle number (number) on the vertical axis, and the number-average particle size and maximum particle size are determined from the obtained cumulative distribution data based on number. The particle size of the plant-based carbide particles can be adjusted by known methods such as sieving.

[0020] The plant-based carbide particles may be a pulverized product obtained by pulverizing a carbide as needed. As a pulverizer used for pulverizing the carbide, 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 can be used.

[0021] The BET specific surface area of ​​the plant-based carbonized particles is set to 400 to 1500 m from the viewpoint of odor reduction. ２ / g, and 600 to 1500m ２ The BET specific surface area of ​​the plant-derived carbide particles is a value measured in accordance with the static volume method described in JIS Z 8830:2013 "Method for measuring the specific surface area of ​​powders (solids) by gas adsorption," except that pretreatment is performed at 550°C and nitrogen gas is used as the adsorbate.

[0022] From the viewpoint of the mechanical properties of the molded article, the plant-derived carbide particles preferably have a drying loss of 5% by weight or less, more preferably 3% by weight or less, as measured in accordance with JIS K 1474:2014.

[0023] Commercially available charcoal may be used as the plant-based charcoal particles. For example, coconut shell activated carbon (trade name: "Shirasagi DO-2" manufactured by Osaka Gas Chemicals Co., Ltd., total acidic functional group content: 0.07 mmol / g, total basic functional group content: 0.83 mmol / g, maximum particle size: 75 μm, BET specific surface area: 1000 m) may be used. ２ / g), activated wood carbon manufactured by Futamura Chemical Co., Ltd. (trade name "Futamura A", total acidic functional group content 0.7 mmol / g, total basic functional group content 0.3 mmol / g, maximum particle size 75 μm), sawdust carbonized material manufactured by Nara Tanka Kogyo Co., Ltd. (trade name "Plus-1", pH = 9.7, total acidic functional group content 0.27 mmol / g, total basic functional group content 0.57 mmol / g, maximum particle size 10 μm), and activated wood carbon manufactured by Osaka Gas Chemicals Co., Ltd. (trade name "Shirasagi C", pH = 11.3, total acidic functional group content 0.03 mmol / g, total basic functional group content 1.2 mmol / g, BET specific surface area 1200 m ２ / g, maximum particle size 75 μm), peat charcoal activated carbon manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. (trade name: "Activated Carbon", pH = 7.5, total acidic functional group content 0.48 mmol / g, total basic functional group content 1.4 mmol / g, maximum particle size 150 μm), etc. can be used.

[0024] The plant-derived carbide particles may be used alone or in combination of two or more kinds.

[0025] The acid-modified polyolefin resin in the present invention is a modified polyolefin resin having a carboxyl group (carboxy group). The acid-modified polyolefin resin is not particularly limited, but is preferably a modified polyolefin resin obtained by reacting a polyolefin resin or a thermal degradation product of a polyolefin resin with an unsaturated (poly)carboxylic acid (or its anhydride).

[0026] Examples of polyolefin resins that can be used as raw materials for acid-modified polyolefin resins include ethylene unit-containing (co)polymers [polyethylene and copolymers of ethylene and unsaturated monomers having 4 to 30 carbon atoms (1-butene, 2-butene, 1-hexene, etc.)], propylene unit-containing (co)polymers [polypropylene and copolymers of propylene and unsaturated monomers having 4 to 30 carbon atoms (1-butene, 2-butene, 1-hexene, 1,4-hexadiene, etc.)], and copolymers containing ethylene units and propylene units [propylene / ethylene copolymers]. Examples of copolymers include propylene / ethylene / 1-butene copolymers, propylene / ethylene / 1-alkene (carbon number 5 to 20) copolymers, and ethylene / propylene / 1,4-hexadiene copolymers, and polybutenes (poly-1-butene and poly-2-butene, etc.). These copolymers are commercially available as Tafmer XM-5070 [manufactured by Mitsui Chemicals, Inc.], Tafmer XM-5080 [manufactured by Mitsui Chemicals, Inc.], VESTOPLAST 750 [manufactured by Evonik], and Versify 3000 [manufactured by The Dow Chemical Company]. In the present invention, the term "(co)polymer" refers to a homopolymer or copolymer of a monomer, and "propylene / ethylene copolymer" refers to a copolymer of "propylene" and "ethylene" before and after " / ". Similarly, other copolymers with names containing " / " refer to a copolymer of the monomers before and after " / ".

[0027] As the thermal degradation product of polyolefin resin, thermally decomposed polyolefin resin can be used, which can be obtained by a method in which polyolefin resin is thermally degraded continuously or discontinuously under nitrogen aeration in the absence of organic peroxide at a temperature of 300°C or higher and 450°C or lower for 0.5 to 10 hours (thermal degradation method 1), or by a method in which polyolefin resin is thermally degraded continuously or discontinuously in the presence of organic peroxide at a temperature of 180°C or higher and lower than 300°C for 0.5 to 10 hours (thermal degradation method 2).

[0028] Examples of unsaturated (poly)carboxylic acids (or anhydrides thereof) include unsaturated monocarboxylic acids, unsaturated polycarboxylic acids (such as unsaturated dicarboxylic acids), and anhydrides thereof (such as unsaturated dicarboxylic acid anhydrides). Salts of unsaturated (poly)carboxylic acids (such as alkali metal salts) may also be used. Examples of unsaturated monocarboxylic acids include linear aliphatic unsaturated monocarboxylic acids having 3 to 24 carbon atoms (hereinafter sometimes abbreviated as C) (such as acrylic acid and methacrylic acid), alicyclic unsaturated monocarboxylic acids having 7 to 24 carbon atoms (such as cyclohexenecarboxylic acid, cycloheptenecarboxylic acid, bicycloheptenecarboxylic acid, and 6-methyl-1-cyclohexenecarboxylic acid), and aromatic unsaturated monocarboxylic acids having 7 to 24 carbon atoms (such as 4-vinylbenzoic acid). Examples of unsaturated dicarboxylic acids include C4-24 linear aliphatic unsaturated dicarboxylic acids (maleic acid, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, etc.), C8-24 alicyclic unsaturated dicarboxylic acids (cyclohexene dicarboxylic acid, cycloheptene dicarboxylic acid, bicycloheptene dicarboxylic acid, methyltetrahydrophthalic acid, etc.), and C8-24 aromatic unsaturated dicarboxylic acids (4,4'-stilbene dicarboxylic acid, etc.). Examples of unsaturated dicarboxylic acid anhydrides include maleic anhydride, itaconic anhydride, citraconic anhydride, etc. Salts of unsaturated (poly)carboxylic acids include alkali metal salts (sodium salts, potassium salts, etc.) of the unsaturated (poly)carboxylic acids. Of these unsaturated (poly)carboxylic acids (or their anhydrides), unsaturated dicarboxylic acid anhydrides are preferred from the viewpoint of reactivity with polyolefin resins, and maleic anhydride is more preferred.

[0029] Known methods can be used to react a polyolefin resin or a thermal degradation product of a polyolefin resin with an unsaturated (poly)carboxylic acid (or anhydride thereof). For example, a method can be used in which the polyolefin resin or a thermal degradation product of a polyolefin resin and the unsaturated (poly)carboxylic acid (or anhydride thereof) are dissolved in an organic solvent, if necessary, and heated (preferably at 100 to 270°C, more preferably at 120 to 250°C, and particularly preferably at 130 to 240°C) in the presence of a radical polymerization initiator, if necessary. Examples of the organic solvent include hydrocarbon solvents (hexane, heptane, octane, dodecane, benzene, toluene, xylene, etc.), halogenated hydrocarbon solvents (di-, tri-, or tetrachloroethane, dichlorobutane, etc.), ketone solvents (acetone, methyl ethyl ketone, di-t-butyl ketone, etc.), and ether solvents (ethyl n-propyl ether, di-n-butyl ether, di-t-butyl ether, dioxane, etc.). As the radical polymerization initiator, an azo initiator (such as azobisisobutyronitrile), a peroxide initiator (such as dicumyl peroxide), or the like can be used.

[0030] The acid value of the acid-modified polyolefin resin in the present invention is 3 to 40 mgKOH / g. If the acid value of the acid-modified polyolefin resin is less than 3 mgKOH / g, the dispersibility of the plant-based char particles will be insufficient, resulting in a reduced odor reduction effect. If the acid value exceeds 40 mgKOH / g, the oxidative decomposition of the thermoplastic resin will be accelerated, increasing the amount of odorous components generated. From the viewpoints of dispersibility of the plant-based char particles and suppression of decomposition of the thermoplastic resin, the acid value of the acid-modified polyolefin resin is preferably 5 to 40 mgKOH / g, more preferably 10 to 30 mgKOH / g. The acid value of the acid-modified polyolefin resin can be adjusted to a predetermined range by adjusting the molar ratio of each compound to be reacted with the polyolefin resin or thermal degradation product of the polyolefin resin and the unsaturated (poly)carboxylic acid (or its anhydride).

[0031] The acid value of the acid-modified polyolefin resin is a value obtained by measuring in accordance with the potentiometric titration method described in JIS K 0070:1992, "Test methods for acid value, saponification value, ester value, iodine value, hydroxyl value, and unsaponifiable matter of chemical products," according to the following steps (i) to (iii). (i) 1 g of acid-modified polyolefin resin is dissolved in 100 g of xylene adjusted to 100°C. (ii) At the same temperature, potentiometric titration is performed with a 0.1 mol / L potassium hydroxide ethanol solution [trade name "0.1 mol / L ethanolic potassium hydroxide solution," manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.] using phenolphthalein as an indicator. (iii) The amount of potassium hydroxide required for the titration is converted to mg to calculate the acid value (unit: mgKOH / g).

[0032] The weight average molecular weight (hereinafter sometimes referred to as Mw) of the acid-modified polyolefin resin is preferably 10,000 to 100,000, more preferably 30,000 to 70,000, from the viewpoint of dispersibility of the plant-based carbonized particles. The Mw of the acid-modified polyolefin resin can be adjusted by selecting the molecular weight of the polyolefin resin or the thermal degradation product of the polyolefin resin to be reacted with the unsaturated (poly)carboxylic acid (or its anhydride). The weight average molecular weight is a value measured by GPC (gel permeation chromatography), specifically, a value measured by the following method. Apparatus: High-temperature gel permeation chromatograph ["Alliance GPC V2000", manufactured by Waters] Detector: Refractive index detector Solvent: Orthodichlorobenzene Reference material: Polystyrene Sample concentration: 3 mg / ml Column stationary phase: PLgel 10 μm, MIXED-B, two columns in series [manufactured by Polymer Laboratories] Column temperature: 135°C

[0033] As the acid-modified polyolefin resin, commercially available products can be used, and preferred examples include UMEX 1001 [acid-modified polypropylene resin, manufactured by Sanyo Chemical Industries, Ltd., acid value 26 mg KOH / g] and UMEX 5200 [acid-modified polypropylene resin, manufactured by Sanyo Chemical Industries, Ltd., acid value 3.5 mg KOH / g].

[0034] The acid-modified polyolefin resin may be used alone or in combination of two or more kinds.

[0035] The molding resin composition of the present invention contains a thermoplastic resin other than the acid-modified polyolefin resin (hereinafter abbreviated as thermoplastic resin).

[0036] Examples of thermoplastic resins include acrylic resins, polyester resins (polyethylene terephthalate, polybutylene succinate, etc.), polyacetal resins, polyolefin resins without carboxyl groups (e.g., (co)polymers of monomers such as ethylene, propylene, butene, and isobutylene), polystyrene resins, polyamide resins, ABS resins, phenolic resins, and fluororesins. Recycled thermoplastic resins (e.g., recycled polypropylene, recycled ABS, and recycled polystyrene) obtained by material recycling of recovered plastic products are also acceptable. The polyolefin resin without carboxyl groups is a polyolefin resin other than the acid-modified polyolefin resins described above, and preferably an unmodified polyolefin resin to which no polar functional groups (e.g., carboxyl groups, amino groups, and hydroxyl groups) have been added. Propylene (co)polymers as the polyolefin resin having no carboxyl groups include random polypropylenes in which a small amount of ethylene is copolymerized with propylene, and block polypropylenes in which ethylene propylene rubber (EPR), a rubber component, is uniformly and finely dispersed in polypropylene (e.g., SunAllomer PM970A manufactured by SunAllomer Co., Ltd.) In addition, examples of thermoplastic resins that can be used include bioplastics such as polyvinyl alcohol resins for melt molding, polylactic acid resins made from starch, and thermoplastic resins made from modified starch, as well as composite bioplastics that are mixtures of the above-mentioned thermoplastic resins with biomass fillers such as starch, wood flour, shells, and cellulose, which are odor-generating fillers.

[0037] The thermoplastic resins may be used alone or in combination of two or more.

[0038] As the thermoplastic resin, polyester resin, polyolefin resin having no carboxyl group, polystyrene resin, and ABS resin can be preferably used, and block polypropylene, polybutylene succinate, polystyrene resin, ABS resin, recycled polypropylene, recycled ABS, and recycled polystyrene are more preferred. Furthermore, as the thermoplastic resin, the bioplastics and composite bioplastics described above can also be preferably used, and composite bioplastics made of starch and polybutylene succinate are more preferred.

[0039] The thermoplastic resin preferably contains a polyolefin resin other than an acid-modified polyolefin resin, more preferably contains a polyolefin resin having no carboxyl groups, and even more preferably contains a polyolefin resin having no carboxyl groups and another thermoplastic resin.

[0040] The content of the plant-derived char particles in the molding resin composition of the present invention is preferably 0.5 to 10 wt %, more preferably 1 to 8 wt %, and even more preferably 2 to 6 wt %, based on the total weight of the plant-derived char particles, acid-modified polyolefin resin, and thermoplastic resin. A weight ratio of the plant-derived char particles of 0.5 to 10 wt % is preferred because it tends to reduce the amount of odor while suppressing a decrease in the strength of the molded article.

[0041] The weight proportion of the acid-modified polyolefin resin in the molding resin composition of the present invention is preferably 1 to 300% by weight, more preferably 1 to 100% by weight, and even more preferably 5 to 50% by weight, based on the weight of the plant-derived carbonized particles. When the weight proportion of the acid-modified polyolefin resin is 1 to 300% by weight based on the weight of the plant-derived carbonized particles, this tends to reduce the amount of odor while suppressing a decrease in the strength of the molded article, which is preferable.

[0042] The weight ratio of the acid-modified polyolefin resin to the total weight of the plant-derived carbonized particles, the acid-modified polyolefin resin, and the thermoplastic resin is preferably 0.05 to 5 wt%, more preferably 0.05 to 3 wt%, and even more preferably 0.1 to 2 wt%. When the weight ratio of the acid-modified polyolefin resin is 0.05 to 5 wt%, the amount of odor tends to be reduced while suppressing a decrease in the strength of the molded article, which is preferable.

[0043] The molding resin composition of the present invention may further contain known additives used in molding resin compositions, such as antistatic agents, colorants, antioxidants, ultraviolet absorbers, infrared absorbers, plasticizers, antiblocking agents, flame retardants, and fillers.

[0044] The molding resin composition of the present invention may be in the form of a masterbatch containing a high concentration of plant-derived char particles, and the content of the plant-derived char particles can be adjusted to a desired value by diluting the masterbatch with a thermoplastic resin and / or an acid-modified polyolefin resin.

[0045] From the viewpoint of the dispersibility of the plant-based carbonized particles, the content of the plant-based carbonized particles in the masterbatch is preferably 20 to 80% by weight, more preferably 40 to 60% by weight, based on the total weight of the plant-based carbonized particles, the acid-modified polyolefin resin, and the thermoplastic resin.

[0046] From the viewpoint of dispersibility of the plant-derived carbonized particles, the weight proportion of the acid-modified polyolefin resin in the masterbatch is preferably 1 to 15 wt %, more preferably 4 to 10 wt %, based on the weight of the plant-derived carbonized particles.

[0047] From the viewpoint of dispersibility of the plant-based carbide particles, the thermoplastic resin in the masterbatch is preferably a polyolefin resin having no carboxyl group.

[0048] The method for producing the molding resin composition of the present invention is not particularly limited, and can be obtained, for example, by melt-kneading the plant-based char particles, acid-modified polyolefin resin, and thermoplastic resin using a known continuous kneader such as a single-screw or twin-screw extruder, a continuous kneader, or a batch kneader. The plant-based char particles, acid-modified polyolefin resin, and thermoplastic resin may be melt-kneaded once or multiple times. It is preferable to melt-knead multiple times, and it is preferable to first obtain a masterbatch containing a high concentration of plant-based char particles by melt-kneading at least once, and then further melt-knead with the thermoplastic resin, etc.

[0049] There is no limitation on the order of mixing the plant-based carbide particles, acid-modified polyolefin resin, and thermoplastic resin. However, from the viewpoint of dispersibility of the plant-based carbide particles, it is preferable to add the plant-based carbide particles to a mixture of the acid-modified polyolefin resin and the thermoplastic resin and mix them. For example, the plant-based carbide particles may be added to a melt-kneaded mixture of the acid-modified polyolefin resin and the thermoplastic resin, followed by further melt-kneading. The masterbatch may be produced in this mixing order. Furthermore, when diluting the masterbatch with a thermoplastic resin, it is preferable to first melt-knead the thermoplastic resin, then add the masterbatch, and further melt-knead. If necessary, the acid-modified polyolefin resin and / or the plant-based carbide particles may be added together with the masterbatch.

[0050] The molding resin composition of the present invention can be used to produce molded articles using known molding methods such as injection molding, extrusion molding, blow molding, and inflation molding.

[0051] The present specification discloses the following:

[0052] The present disclosure (1) is a molding resin composition comprising plant-based carbonized particles, an acid-modified polyolefin resin, and a thermoplastic resin other than the acid-modified polyolefin resin, wherein the plant-based carbonized particles have a total acidic functional group content of 0.02 to 1.0 mmol / g and a total basic functional group content of 0.3 to 1.9 mmol / g, as measured by an acid-base neutralization titration method, and the acid-modified polyolefin resin has an acid value of 3 to 40 mgKOH / g.

[0053] The present disclosure (2) is the molding resin composition according to the present disclosure (1), wherein the thermoplastic resin contains a polyolefin resin other than the acid-modified polyolefin resin.

[0054] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0055] In the examples and comparative examples, the following plant-based carbonized particles, acid-modified polyolefin resins, and thermoplastic resins were used. <Plant-based carbonized particles> Plant-based carbonized particles (A-1): coconut shell activated carbon [trade name "Shirasagi DO-2", manufactured by Osaka Gas Chemicals Co., Ltd., pH = 11.4, total acidic functional group content 0.07 mmol / g, total basic functional group content 0.83 mmol / g, BET specific surface area 1000 m ２ / g, maximum particle size 75 μm]. Plant-based carbonized particles (A-2): wood-based activated carbon [trade name "Futamura A", manufactured by Futamura Chemical Co., Ltd., pH = 6.4, total acidic functional group content 0.7 mmol / g, total basic functional group content 0.3 mmol / g, maximum particle size 75 μm]. Plant-based carbonized particles (A-3): sawdust carbon [trade name "Plus-1", manufactured by Nara Tanka Kogyo Co., Ltd., pH = 9.7, total acidic functional group content 0.27 mmol / g, total basic functional group content 0.57 mmol / g, maximum particle size 10 μm]. Plant-based carbonized particles (A-4): wood-based activated carbon [trade name "Shirasagi C", manufactured by Osaka Gas Chemicals Co., Ltd., pH = 11.3, total acidic functional group content 0.03 mmol / g, total basic functional group content 1.2 mmol / g, BET specific surface area 1200 m ２ / g, maximum particle size 75 μm] Plant-based carbonized particles (A-5): peat carbon activated carbon [trade name "Activated Carbon", Fujifilm Wako Pure Chemical Industries, Ltd., pH = 7.5, total acidic functional group content 0.48 mmol / g, total basic functional group content 1.4 mmol / g, maximum particle size 150 μm]

[0056] <Acid-modified polyolefin resin> Acid-modified polyolefin resin (B-1): Umex 1001 [manufactured by Sanyo Chemical Industries, Ltd., acid value 26 mg KOH / g, weight average molecular weight 45,000] Acid-modified polyolefin resin (B-2): Umex 5200 [manufactured by Sanyo Chemical Industries, Ltd., acid value 3.5 mg KOH / g, weight average molecular weight 9,000] Acid-modified polyolefin resin (comparison B-1): Umex 1010 [manufactured by Sanyo Chemical Industries, Ltd., acid value 52 mg KOH / g, weight average molecular weight 23,000] <Thermoplastic resin> Thermoplastic resin (C-1): Block polypropylene for injection molding [trade name: SunAllomer PM970A, manufactured by SunAllomer Co., Ltd., MFR = 30 (g / 10 min)] Thermoplastic resin (C-2): Polybutylene succinate [trade name: BioPBS FZ71, manufactured by PTT MCC Biochem, MFR = 22 (g / 10 min)] Thermoplastic resin (C-3): ABS resin [trade name: TOYOLAC 700X01U, manufactured by Toray Industries, Inc., MFR = 40 (g / 10 min)] Thermoplastic resin (C-4): polystyrene resin [trade name: PSJ-Polystyrene 679, manufactured by PS Japan Co., Ltd., MFR = 18 (g / 10 min)] Thermoplastic resin (C-5): composite bioplastic obtained in Production Example 1 below Thermoplastic resin (C-6): recycled polypropylene [trade name: TPC-PPC 05 / 2, manufactured by Teamlas Chemical Co., Ltd., MFR = 13 (g / 10 min)] Thermoplastic resin (C-7): recycled ABS [trade name: DENKA "TE-10S" manufactured by Denka Co., Ltd. was melt-mixed at 230°C in a vented twin-screw extruder at a rotation speed of 100 rpm for a residence time of 25 minutes, and the resulting pellets were obtained by melt-mixing the polystyrene (product name "HIPS 433" manufactured by PS Japan Co., Ltd.) ...

[0057] <Production Example 1> 2.0 parts by weight of acid-modified polyolefin resin (comparison B-1) (UMEX 1010), 2.0 parts by weight of thermoplastic polyester resin polybutylene succinate (trade name: BioPBS FZ91, MFR (190°C, 2.16 kg) = 5 (g / 10 min), PTT MCC 50.0 parts by weight of starch (derived from wheat flour, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), 40 parts by weight of starch, and 10 parts by weight of D-sorbitol were placed in a polypropylene beaker and pre-mixed by gently stirring with a stirring blade. The mixture was then kneaded for 10 minutes using a Laboplastomill (registered trademark) (a kneading and extrudability testing device manufactured by Toyo Seiki Seisaku-sho, Ltd.) adjusted to a temperature of 200°C under conditions of a chamber temperature of 200°C and a mixer rotation speed of 60 rpm, to obtain a composite bioplastic (C-5) containing starch, polybutylene succinate, and the like.

[0058] Example 1 The plant-based carbide particles (A-1) and acid-modified polyolefin resin (B-1) in the amounts shown in Table 1 were placed in a polypropylene beaker and gently stirred with a stirring blade to obtain a premixed mixture. The thermoplastic resin (C-1) in the amount shown in Table 1 was mixed in the kneading section of a Labo Plastomill (registered trademark) adjusted to 220°C for 1 minute at a stirring section rotation speed of 10 rpm, and then the mixture premixed in the polypropylene beaker was added, followed by melt-kneading for 10 minutes at a stirring section rotation speed of 60 rpm. The kneaded mixture was removed from the Labo Plastomill and molded into a thickness of 5 mm using a pressure molding machine adjusted to the same temperature as the melt-kneading temperature in the Labo Plastomill. The mixture was then cut using a pelletizer to obtain a molding resin composition [masterbatch pellets (MB1)] according to Example 1.

[0059] Examples 2 to 5 Molding resin compositions [masterbatch pellets (MB2 to MB5)] according to Examples 2 to 5 were obtained by performing melt-kneading, molding, and cutting in the same manner as in Example 1, except that the types and amounts of the plant-derived carbonized particles, acid-modified polyolefin resin, and thermoplastic resin were changed to those shown in Table 1, and the temperatures at which the Labo Plastomill and the pressure molding machine were regulated were changed to those shown in Table 1.

[0060]

[0061] Examples 6-20, Comparative Example 1 Thermoplastic resins of the types and amounts shown in Tables 2-1 and 2-2 were added to the kneading section of a Labo Plastomill, the temperature of which was adjusted to the temperatures shown in Tables 2-1 and 2-2. Mixing was performed for 1 minute at a stirring speed of 10 rpm. The plant-based carbide particles, acid-modified polyolefin resin, and masterbatch pellets produced in Examples 1-5 were then added to the kneading section at the types and amounts shown in Tables 2-1 and 2-2. The mixture was melt-kneaded for 10 minutes at a stirring speed of 60 rpm. The kneaded mixture was then removed from the Labo Plastomill, cooled to room temperature, and pulverized in a laboratory benchtop pulverizer to obtain molding resin compositions according to Examples 6-20 and Comparative Example 1. The resulting molding resin compositions were measured for molded article odor, the amount of odor-causing substances generated by heating the molded articles, and the tensile strength of the molded articles using the methods described below.

[0062]

[0063]

[0064] <Odor of Molded Articles> Each of the molding resin compositions obtained in Examples 6 to 20 and Comparative Example 1 was hot-molded into a 2 mm thick plate using a hot-press molding machine heated to the same temperature as the Labo Plastomill temperature listed in Tables 2-1 and 2-2, and then cut into a 100 mm x 100 mm x 2 mm piece to obtain a test molded article. The obtained test molded article was placed in a 2 L glass desiccator, the lid was closed, and the desiccated article was left to stand at 40°C. After 24 hours of standing, the lid was slightly opened, the desiccated article was smelled, and the odor intensity was evaluated on a 5-point scale from 0 to 4 (odor intensity 0 to odor intensity 4) according to the following criteria. Five panelists performed this evaluation, and the average of the scores of the five panelists was rounded off. The results are shown in Tables 3-1 and 3-2.・0 points (odor intensity 0): Odorless ・1 point (odor intensity 1): Odor can barely be detected ・2 points (odor intensity 2): Slight odor ・3 points (odor intensity 3): Odor can be detected ・4 points (odor intensity 4): Strong odor

[0065] <Amount of Odor-Causing Substances Produced Upon Heating of Molded Articles> For each of the molding resin compositions and thermoplastic resins (C-5) to (C-8) obtained in Examples 6 to 20 and Comparative Example 1, test molded articles identical to those used to evaluate the odor of the molded articles were prepared. The temperatures of the Labo Plastomill used to mold the thermoplastic resins (C-5) to (C-8) were 180°C for the thermoplastic resin (C-5), 210°C for the thermoplastic resin (C-6), 220°C for the thermoplastic resin (C-7), and 200°C for the thermoplastic resin (C-8). The resulting molded articles were freeze-pulverized in a small freeze-pulverizer (pre-cooling time under liquid nitrogen: 10 minutes, pulverization time: 20 minutes), and the amounts of odor-causing substances (acetaldehyde, acetic acid, toluene, undecane, and styrene) produced upon heating the pulverized product (sample) were measured using the following method. Approximately 10 mg of sample was weighed out and placed in a TENAX tube, which was then set in a pyrolysis gas chromatography (TD-GC / MS) and measured under the conditions below. For each odor-causing substance, the peak area per 1 mg of sample was calculated from the peak area of ​​each odor-causing substance in the pyrolysis gas chromatography measurement chart. For the molding resin compositions obtained in Examples 6 to 20 and Comparative Example 1, the peak area per 1 mg of sample obtained from molded articles of thermoplastic resins (C-5) to (C-8) was set at 100, and the relative values ​​are shown in Tables 3-1 and 3-2 as the amounts of odor-causing substances generated by heating the molded articles. Regarding the "standards for the amount of substance" in Tables 3-1 and 3-2, "Group 1" means a relative value relative to the peak area of ​​a sample obtained from a molded product of thermoplastic resin (C-5), "Group 2" means a relative value relative to the peak area of ​​a sample obtained from a molded product of thermoplastic resin (C-6), "Group 3" means a relative value relative to the peak area of ​​a sample obtained from a molded product of thermoplastic resin (C-7), and "Group 4" means a relative value relative to the peak area of ​​a sample obtained from a molded product of thermoplastic resin (C-8). Acetaldehyde and acetic acid are known to be odor-causing substances generated by the oxidative decomposition of glucose in thermoplastic resins and starch, while toluene, undecane, and styrene are known to be odor-causing substances generated by thermal decomposition due to heating during molding or recycling of thermoplastic resins. It can be said that the less these chemicals are generated, the less odor is generated.(TD-GC / MS measurement conditions) GC conditions: Apparatus: GCMS-TQ8040 [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 heat to 230°C (heating rate: 10°C / min), hold at 230°C for 10 minutes MS conditions: Ionization mode: EI Detection mode: Scan (m / z = 33 to 300) Detector voltage (relative): 0 kV Tuning voltage: 1.09 kV.

[0066] <Tensile strength of molded articles> For each of the molding resin compositions obtained in Examples 6 to 20 and Comparative Example 1, test molded articles identical to those used to evaluate the odor of the molded articles were prepared, and the tensile strength was measured in accordance with ASTM D 638. The results are shown in Tables 3-1 and 3-2.

[0067]

[0068]

[0069] As shown in Tables 3-1 and 3-2, the molding resin compositions of each Example have reduced odor in molded articles and reduced the amount of odor-causing substances generated by high-temperature heating of molded articles compared to the resin compositions of the Comparative Examples. These results indicate that the present invention can reduce the amount of odor-causing substances, including highly polar substances, generated from molded articles due to decomposition (oxidative decomposition and thermal decomposition) of the components of the resin composition. It also suggests that the amount of odor-causing substances generated during processing and heating during molding can be reduced, not just after molding.

[0070] The molding resin composition of the present invention provides low-odor molded articles that emit little odor even when heated at high temperatures, and is therefore extremely useful for a wide range of applications, including housing products (such as for home appliances, office automation equipment, game machines, and office equipment), plastic containers (such as food trays, tableware, trays used in clean rooms (such as IC trays), and other containers), various cushioning materials, covering materials (such as packaging films and protective films), flooring sheets, artificial turf, mats, tape substrates (such as for semiconductor manufacturing processes), and various molded articles (such as automobile parts).

Claims

1. A molding resin composition comprising plant-derived carbonized particles, an acid-modified polyolefin resin, and a thermoplastic resin other than the acid-modified polyolefin resin, wherein the plant-derived carbonized particles have a total acidic functional group content of 0.02 to 1.0 mmol / g and a total basic functional group content of 0.3 to 1.9 mmol / g, as measured by acid-base neutralization titration, and the acid-modified polyolefin resin has an acid value of 3 to 40 mg KOH / g.

2. The molding resin composition according to claim 1, wherein the thermoplastic resin contains a polyolefin resin other than the acid-modified polyolefin resin.

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