JP2016050210A - Resin material for molding comprising bran and resin, and method for producing the same, and molded article comprising the resin material for molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin material for molding comprising bran and thermoplastic resin with reduced frequency of breakage during injection molding and others.SOLUTION: A resin material for molding is obtained by heating and mixing crushed bran and thermoplastic resin so that the percentage of bran becomes 40 mass% or more and less than 60 mass%.SELECTED DRAWING: None

Description

  The present invention relates to a thermoplastic molding material using bran and a thermoplastic resin typified by polypropylene or polyethylene as raw materials, and is characterized in that, in particular, the blended “bran” is pulverized. The present invention relates to a molding resin material and a manufacturing method thereof.

  Biomass materials are attracting attention as industrial resources. The biomass material means a material derived from a living organism such as a plant. Since the biomass material is organic, carbon dioxide is emitted when it is burned. However, the carbon contained in this is derived from carbon dioxide absorbed from the atmosphere by photosynthesis during the growth process, so using biomass materials does not increase the amount of carbon dioxide in the atmosphere as a whole It can be considered that. This property is called carbon neutral.

  Against the backdrop of global environmental issues such as global warming issues, there is an urgent need to conserve resources, material recycling aiming at raw materials for waste, and promotion of the environmental circulation cycle represented by biodegradable plastics. However, the revised Recycling Law and the Green Purchasing Law have been put in place, and the need for products that respond to these laws is increasing.

  Under these circumstances, blending biomass materials into resin molded products that are widely used from automotive parts materials to daily necessities promotes the practice of the carbon neutral philosophy, and is both biomass materials and food waste. In addition, blending into the resin material “Bran (a rice cake obtained when milling wheat)” that is discarded with little use is in line with the recent promotion of the environmental circulation cycle. Japanese Patent No. 3143851 (Patent Document 1) describes that “Bran” and “Powdered polypropylene” are mixed and heated and melted by a molding machine.

Japanese Patent No. 3143851

  However, when simply blending “Bran” and “Polypropylene” and heating and melting to mold, the Bran and Polypropylene cannot be mixed uniformly. There existed problems, such as cut | disconnecting finely, and the surface of the molded article obtained was not smooth.

  Moreover, although it is described in Patent Document 1 that “powdered polypropylene” is used, polypropylene is usually sold in the form of particles having a particle diameter of about 3 to 5 mm and is not a powder. Powdered polypropylene that has been processed into a powder form of about 5 μm in advance is also commercially available (for example, polypropylene powder PPW-5: Seishin Corporation), but the use of such powdered polypropylene in plastic production is a plastic modifier. Therefore, it is not actively used as the main raw material of the resin. It is conceivable to pulverize the granular polypropylene before mixing with the bran and use it in the form of a powder. However, when pulverizing, part of the pulverization energy causes a local increase in the resin temperature, which causes the resin There is a possibility that problems such as melting and fixing occur, and there is a concern that the manufacturing process becomes excessively complicated as a countermeasure. In addition, Patent Document 1 does not describe such a problem.

  Accordingly, the present invention provides a molding material in which bran and resin are uniformly mixed in a thermoplastic molding material in which bran, which is a biomass material, is mixed, so that there is less cutting at the time of molding such as injection. About.

  The present inventors have found that a resin material for molding having excellent molding stability can be obtained by mixing the bran after pulverization with a thermoplastic resin such as polypropylene or polyethylene and kneading with heat. The invention has been completed. In particular, when pulverized bran that has been subjected to γ-ray treatment is mixed with a resin, even if the blending amount of the bran is increased, a product that is inferior in molding stability can be obtained compared to a normal resin that does not contain bran. It was confirmed.

The present invention includes, but is not limited to, the following.
(1) A molding resin material comprising ground bran and a thermoplastic resin, wherein the bran is contained in an amount of 40% by mass or more and less than 60% by mass.
(2) The resin material for molding according to (1), wherein a 90% particle diameter of the bran is 400 μm or less.
(3) The molding resin material according to (1) or (2), wherein the thermoplastic resin is polypropylene and / or polyethylene.
(4) The molding resin material according to any one of (1) to (3), wherein the bran has been subjected to γ-ray irradiation treatment.
(5) A molded article produced from the molding resin material according to any one of (1) to (4).
(6) A method for producing a molding resin material, comprising heating and kneading 40% by mass or more and less than 60% by mass of pulverized bran based on the mass of the thermoplastic resin and the resulting molding resin material.
(7) The production method according to (6), wherein a 90% particle diameter of the bran is 400 μm or less.
(8) The production method according to (6) to (7), wherein the thermoplastic resin is polypropylene and / or polyethylene.
(9) The manufacturing method according to any one of (6) to (8), further including performing γ-ray irradiation treatment on the bran before the heat-kneading.

  According to the present invention, a molding resin material containing bran can be stably produced. Moreover, the resin material for shaping | molding excellent in carbon neutral can be obtained by raising a bran compounding rate. The molding resin material of the present invention can be molded for various purposes by injection molding or the like, and is an alternative to plastic products, that is, various containers such as trays, automobile parts, cards, toner containers, and building materials. It can be widely applied to the manufacture of agricultural sheets, writing instruments, substitutes for wooden products, etc. When these products are no longer needed, they will be disposed of. For example, even if they are incinerated and emit carbon dioxide, the blended bran will reduce the amount of carbon dioxide in the atmosphere. It can be handled as not increasing.

  The bran used as a raw material in the present invention may be a waste (rice cake) generated when wheat is milled. Bran is commercially available. The bran is usually a granular material containing particles of various sizes having a particle size distribution with a 90% particle size of about 1300 μm and a 10% particle size of about 70 μm. In the present invention, a powdered product is used. .

  In pulverizing the bran, the 90% particle diameter of the bran is preferably 400 μm or less, and more preferably 300 μm or less. If the bran 90% particle size is larger than 400 μm, uniform mixing with the resin becomes difficult, and the resin body is cut into small pieces at the outlet of the apparatus that injects the mixture of bran and resin. Problems such as The 10% particle size of the pulverized bran is preferably 20 μm to 40 μm. Such a bran can be obtained by pulverizing the bran using a pulverizer as exemplified below and then classifying it by a method as exemplified below, if necessary.

  The measurement of the particle size of the bran is not limited, but can be performed using, for example, a laser diffraction particle size distribution measuring apparatus.

  The pulverizer used when pulverizing the bran may be an apparatus capable of pulverizing organic matter, for example, but not limited to, a ball mill, a rod mill, a bead mill, a conical mill, a disk mill, an edge mill, a hammer mill, a mortar, a pellet mill, A VSI mill, a wheelie mill, a roller mill, a jet mill, etc. can be used.

  In addition, when classifying the bran, either wind classification or sieving may be used.For example, although not limited to these, in the wind classification, there are a gravity head wind type and a forced centrifugal wind type. , Vibration screen type, circular vibration type, rotary type, cylindrical stirring type, ultrasonic type, blower shifter type and the like. The maximum particle size of the bran recovered by classification is preferably about 800 μm, more preferably about 500 μm.

  The pulverized bran used in the present invention is preferably subjected to γ-ray irradiation treatment. An apparatus used for sterilization of food packaging materials can be used for γ-ray irradiation, but is not limited thereto. The dose of γ rays is preferably 5 KGy to 25 KGy, more preferably 7 KGy to 10 KGy.

  When gamma irradiation treatment is performed, uniform mixing of the bran and the thermoplastic resin is promoted. In addition, organic substances such as bran may generate gas when heated, which may cause processing troubles in resin processing and molding processing and problems of product quality degradation. When the irradiation treatment is performed, it becomes possible to decompose components that are the sources of gas generation, so that gas generation and foaming during subsequent heating can be prevented.

  The γ-ray irradiation history of bran can be analyzed in the same manner as the analysis method of the γ-ray irradiation history of ordinary foods. Examples of the method include ESR method, TL method, PSL method, GC method, comet assay method. DEFT / APC method and LAL / GNB method. Among these, the ESR method excellent in detection of cellulose is preferable because it is suitable for confirming the irradiation history in the molding resin material of the present invention. The irradiation history of gamma rays of bran can be confirmed by appropriately using an inspection apparatus developed for food inspection that can practice such a method.

  The molding resin material of the present invention can be obtained by heating and kneading the bran with a thermoplastic resin. The blending ratio of the bran in the molding resin material is preferably high in order to realize carbon neutral at a high level, but considering the production and strength of the obtained resin material and molded article, it is 40% by mass or more. Less than mass% is suitable, More preferably, it is 45 mass% or more and less than 55 mass%. In addition, the mass of bran here refers to the mass at the time of preparing about 5-10% (WB) of water content.

  The thermoplastic resin used in the present invention is preferably in the form of a granule in terms of ease of handling, but may be in any form. Two or more types of thermoplastic resins can also be used simultaneously. A biodegradable resin having thermoplasticity is also included. Furthermore, at the time of kneading with bran, a compatibilizing resin that is also a thermoplastic resin may be added for the purpose of improving uniformity and adhesion.

  Examples of the thermoplastic resin include, but are not limited to, polyethylene, polypropylene, and L-LDPE, and any resin that can be plasticized and molded by heat can be used. Among these, polyethylene and polypropylene are preferable from the viewpoint of moldability.

  Examples of the biodegradable resin having thermoplasticity include, but are not limited to, polylactic acid (PLA), polybutylene succinate, polyethylene succinate, polyglycol, polycaprolactone, and polyvinyl alcohol.

  As the compatibilizing resin, known resins can be used, and examples thereof include, but are not limited to, Modic (registered trademark) P908 (manufactured by Mitsubishi Chemical). The compatibilizing resin functions to increase the uniform mixing and adhesion between the bran and the thermoplastic resin. The compatibilizing resin may not be used, but when used, it is used in an amount of up to about 6% by mass in the molding resin material obtained by kneading.

  In the method for producing a molding resin material of the present invention, bran and a thermoplastic resin are heated and kneaded. For heat-kneading, an apparatus used for general resin molding can be used. For example, a general extruder can be used.

  Various molded articles can be produced using the molding resin material of the present invention. The molding can be performed by a usual method used for molding a thermoplastic resin. For example, but not limited to, injection molding, extrusion molding, blow molding and the like can be performed.

  The molding resin material of the present invention is produced by heating and kneading bran and a thermoplastic resin. The material after heating and kneading (mixture of bran and thermoplastic resin) is directly injected into a predetermined mold. It is good also as a molded article.

  In the present invention, the bran is pulverized before being kneaded with the thermoplastic resin. Further, the bran may be pre-processed using a γ-ray irradiator. By these treatments, the thermoplastic resin and the bran are mixed uniformly. Cellulose is cut by gamma rays. Although other principles are not clear, there is a possibility that the particle size is reduced by pulverization and the specific surface area is increased, or that the surface charge is increased by γ-ray treatment.

  The molding resin material of the present invention or the molded article obtained by molding it may contain an organic substance and / or an inorganic substance other than the resin and bran, for example, a substance having an odor that induces animals and insects. Alternatively, repellent substances may be included. The mixing ratio of components other than bran and resin is about 5 to 10% by mass based on the mass of the molding resin material or the molded article, considering the strength of the molding resin material and the molding stability. is there.

  The attracting substance is a chemical substance such as a carboxylic acid ester having a cyclohexyl group, an aromatic fatty acid ketone, a ketone having 7 to 9 carbon atoms, vanillin, ethyl vanillin, isovanillin, piperonal, piperonal acetone, 2,6- Nonadiether and the like are listed, and examples of natural substances include sugars, alcohols, carboxylic acids, yeasts, nucleic acids, pheromone substances, and the like. In the case of natural substances, food waste may be used, and examples thereof include, but are not limited to, grain residues, vegetable residues, fruit residues, fish meat residues, meat residues, and the like.

  The repellent is a chemical substance such as dichlorvos, phenanthion, temefos, trichlorfone, propetanephos, pyrethroid ester compound, diet (N, N-dimethyl-m-toluamide), cinnamyl alcohol, cinnamyl acetate, eugenol, safrole, imiprotorin. , Phthalthrin, allethrin, bifenthrin, resmethrin, phenothrin, ciphenothrin, permethrin, cypermethrin, etofenprox, sifluthrin, deltamethrin, fenvalerate, fenpropraslin, silafluophene, fenitrothion, diazinon, marathon, pyridafenthione, prothiophos, oxime, chlorpyriphos , Propoxur, mesomil, thiodicarb, methoxadiazone, phyto Ronyl, amidoflumet, dinotefuran, imidacloprid, methoprene, pyriproxyfen, chlorfenapyr, ethylbutylacetylaminopropionate, etc., natural substances include capsaicin, bamboo vinegar, turmeric, etc. Waste may be used, and examples include, but are not limited to, chili residue, citrus plant residue, grapefruit seed residue, wasabi residue and the like.

  Furthermore, other commercially available drugs can be used as appropriate for both the attractant and repellent.

  In the case of a molding resin material containing an attracting substance or a repellent substance and a molded article using the molding resin material, an incentive or repellent effect can be obtained according to the contained substance. Since these incentives or repellent substances are gradually released from the molding resin material or the molded article, they are superior to using the substance alone in terms of durability of the effect. Moreover, since it can handle similarly to a normal resin material or a molded article, it is excellent in handleability. In addition, for example, even if the inducer or repellent substance has a characteristic of being easily eluted in water, it can prevent a sudden loss of the effect when exposed to water by kneading with the resin. . Thus, it is an advantageous feature as an attractant and repellent that it is less susceptible to environmental influences in terms of sustained effects.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to these. In addition, unless otherwise indicated, a part and% show a mass part and mass%.

[Test 1: Crushing bran, gamma irradiation]
Using a hammer mill (high-speed hammer mill 1018-S-3; manufactured by Yoshida Seisakusho), a commercial feed bran (manufactured by Nisshin Flour Milling) was pulverized. The rotation speed of the hammer mill was set to 6,500 rpm. The obtained pulverized bran was collected by passing it through a mesh having a pore diameter (corresponding to a screen) of 1.0 mm or 0.7 mm. Similarly, bran that had been previously γ-irradiated and then crushed was also prepared.

  The particle size distribution of the irradiated and pulverized bran is measured using a laser diffraction type particle size distribution measuring device, specifically, wet measurement in which the bran is dispersed in water, and 10% particle size and 90% based on volume. The particle size and the like were calculated. Table 1 shows the 10% particle size and 90% particle size of bran and the absorbed dose upon γ-ray irradiation. In addition, since the raw material bran before processing is coarse, the particle size distribution was measured by a sieving method.

[Test 2: Heat kneading with bran and thermoplastic resin]
Using an extruder (uniaxial type extruder; manufactured by Todai Seiki Co., Ltd.), each of the bran A to E shown in Table 1 and the combinations of the thermoplastic resin and the compatibilizing resin shown in Table 2 are shown in Table 4. Mixing was carried out at the indicated blending ratio, followed by heating and kneading at 160 ° C. to produce a molding resin material containing bran.

  Two types of thermoplastic resins were tested: polypropylene and polyethylene. Table 2 shows combinations of brands of thermoplastic resin and compatibilizing resin used.

  In this test, the bran, the thermoplastic resin, and the compatibilizing resin were heated and kneaded in the extruder, then extruded from the extruder, processed into a linear shape having a diameter of about 3 to 5 mm, cooled, and then cut 3 to 3. The particle size was about 5 mm. In the process up to this cutting, the frequency of cases in which stable production could not be performed due to cutting at an unintended place was evaluated according to the criteria described in Table 3.

  The results of production stability are shown in Table 4. Further, as a reference, an injection molding machine (J85ELIII-110H-MuCell type, manufactured by Nippon Steel Works Co., Ltd.) was used to produce a molded article that was processed and molded into a flower pot shape. The visual evaluation is described in Table 4.

  From the above results, it can be seen that when the pulverized bran (the bran AD) is contained in the range of 40% by mass to 60% by mass (Examples 1 to 8), the molding resin material can be produced. . In particular, it can be seen that in Examples 1 to 3 and Examples 5 to 7 in which the 90% particle size of bran is 400 μm or less, the production stability is high.

  On the other hand, when bran that has not been pulverized (Bran E) was used (Comparative Examples 5 and 10), it was found that even if the blending ratio of the bran was 50% by mass, the production was impossible (x). . In addition, even when pulverized bran is used, it can be seen that even when the bran content is higher than 60% by mass (Comparative Examples 1 to 4 and 6 to 9), it was impossible to manufacture (x). .

Claims (9)

A molding resin material comprising ground bran and a thermoplastic resin, wherein the bran is contained in an amount of 40% by mass or more and less than 60% by mass. The molding resin material according to claim 1, wherein the bran has a 90% particle diameter of 400 μm or less. The molding resin material according to claim 1, wherein the thermoplastic resin is polypropylene and / or polyethylene. The molding resin material according to claim 1, wherein the bran has been subjected to γ-ray irradiation treatment. The molded article manufactured from the resin material for shaping | molding of any one of Claims 1-4. A method for producing a molding resin material, comprising heating and kneading 40% by mass or more and less than 60% by mass of pulverized bran based on the mass of the thermoplastic resin and the resulting molding resin material. The manufacturing method of Claim 6 whose 90-% particle diameter of the said bran is 400 micrometers or less. The production method according to claim 6, wherein the thermoplastic resin is polypropylene and / or polyethylene. The manufacturing method according to any one of claims 6 to 8, further comprising performing γ-ray irradiation treatment on the bran before the heat-kneading.