JP3509750B2 - Method for producing composite molding material for processed vegetable food residue and molding method using the composite molding material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a composite processing material for vegetable food processing residues, which effectively utilizes industrial waste discharged in the food manufacturing industry, and a method for manufacturing a molded article using the molding material. It is a thing.

[0002]

2. Description of the Related Art Okara, which is obtained as squeezed lees of soybean milk in the process of manufacturing tofu, was used as a food material before, but recently, the demand for it has decreased with the Japanese people's preference for food. Only a part of it is used as animal feed and fertilizer, and most of it is left unused and incinerated or landfilled as industrial waste.

[0003] In addition, soybean meal produced during the purification of wheat such as wheat and barley, so-called bran, and refined meal of shells such as buckwheat husks produced during dehulling of buckwheat and pressed meal of edible oil from seeds. Most of them are only used as animal feed and packing materials, and most of them are discarded.

On the other hand, in recent years, the importance of resource recycling type social systems and economic systems that reduce industrial waste and reduce environmental pollution has been recognized, and even in the food-related industrial field, The Law Concerning the Promotion of Reuse of Food Circulation Resources "has been enacted, and the reuse of industrial waste associated with food production is demanded as a social problem.

By the way, it has been attempted to use the plant-processed residue produced during the production of foods such as okara, bran and oil cake as a molding material in combination with a thermoplastic resin such as polyolefin. But,
Even if it is simply mixed with a thermoplastic resin and heat-melted, it is difficult to form a composite. Therefore, in order to obtain a composition that can be used as a molding material, a large amount of thermoplastic resin must be used. Compared with the case of using the thermoplastic resin used alone, the physical properties are inevitably deteriorated. Moreover, in order to make the mixture of these residues and the thermoplastic resin into a homogeneous composition, it is necessary to carry out kneading for a relatively long time under heating, but during this time, it is contained in okara, bran, oil cake, etc. It has not been put to practical use because existing proteins and sugars are decomposed and deteriorated, giving off an offensive odor and causing physical property deterioration.

[0006]

Under the circumstances described above, the present invention provides a molded product using a vegetable residue produced in the food processing process such as okara, bran, and oil cake. The purpose of the present invention is to provide a molding material having physical properties that can be used.

[0007]

SUMMARY OF THE INVENTION The present inventors have generally used a method of mixing a polyolefin with a food residue containing a wide variety of components to produce a molding material, and simply melting and kneading it. If a mixing method is used, it is not possible to obtain a uniform composition, and it is not possible to prevent the food residue from degrading and deteriorating the quality during mixing, but the polyolefin and maleic acid or maleic anhydride cannot be added to the food residue. Modified polyolefin is added, and the resulting mixture is melt-kneaded while crushing by applying mechanical energy in the absence of solvent .
As a result, it was found that if a mechanochemical reaction is carried out, it is possible to combine these components without decomposing the food residue, and the present invention has been completed based on this finding.

Namely, the present invention is left vegetable food processing, a mixture of polyolefin and maleic acid or maleic anhydride-modified polyolefin, dry conditions, 120 to
Do not grind by adding mechanical energy at 190 ℃
To make a mechanochemical reaction to form a composite
A method for producing a composite molding material having a plant food processing residue characterized by the above , and a molding material thus obtained, which is characterized by heat-molding by press molding, extrusion molding or injection molding. It is provided.

According to the present invention, even a plant food processing residue having no thermoplasticity is mixed with a thermoplastic polyolefin and a maleic acid- or maleic anhydride-modified polyolefin, and mechanical energy is applied thereto. By reacting, the polymer compound in the vegetable food processing residue and polyolefin and modified polyolefin react mechanochemically at the molecular level to form a composite,
It becomes a complex that exhibits completely different thermal characteristics from the high molecular compound, and exhibits thermoplasticity.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In the method of the present invention, a plant food processing residue, polyolefin and maleic acid or maleic anhydride modified polyolefin are used as raw material components.
The largest amount of this vegetable food processing residue is okara, which is obtained as a soybean milk meal during the tofu manufacturing process, bran obtained from a grain threshing and refinement process, and squeezed meal after collecting edible oil from plant seeds. It is preferable because it is easily available,
Other vegetable wastes produced during other food processing steps can also be used. Of these food processing residues, those that are originally obtained in granular or powder form, such as okara, bran, and oil cake, can be used as they are, but those obtained as lumps or other solid matter have a particle size of 1 mm. It is preferably used as the following powdery or granular material.

As the polyolefin, for example, homopolymers such as polyethylene, polypropylene, polybutylene and polyisoprene, copolymers of ethylene and propylene, copolymers of ethylene and butylene, ethylene and other carbon numbers. A copolymer with 5 or more α-olefins, that is, a copolymer such as low density linear polyethylene is used. These may be used alone or as a mixture of two or more.

As the maleic acid- or maleic anhydride-modified polyolefin, a polyolefin obtained by graft-copolymerizing maleic acid or maleic anhydride is used. Polyethylene and polypropylene are easily graft-copolymerized with maleic acid or maleic anhydride to form modified polyethylene or modified polypropylene. Since this modified polyolefin has a carboxyl group or an acid anhydride group, these parts easily react with the component having a hydroxyl group in the vegetable food processing residue to develop affinity,
Further, since the polyolefin main chain portion has an affinity with the polyolefin used in combination, this acts as a compatibilizing agent between the plant food processing residue and the polyolefin. As described above, the modified polyolefin acts as a compatibilizing agent, and when it coexists, the content ratio of the plant food processing residue to the polyolefin can be significantly increased.

[0013] Composite residue of plant food processing residue of the present invention
In the production method of 10 to 70 parts by mass of polyolefin, preferably 20 to 60 parts by mass, maleic acid- or maleic anhydride-modified polyolefin 2 to 50 parts by mass, and preferably 5 to 20 parts by mass per 100 parts by mass of plant food processing residue. It is preferable to contain it in a ratio of parts by mass.

Further, in the composite molding material obtained by the method of the present invention, in addition to the plant food processing residue, the polyolefin and the modified polyolefin, if desired, additives conventionally used in ordinary thermoplastic resin molding materials, for example, A plasticizer, a stabilizer, a reinforcing agent, an antioxidant, an ultraviolet absorber, a flame retardant, an antistatic agent, a lubricant, a colorant, an antifungal agent and the like can be added in respective effective concentrations.

In the method of the present invention, a mixture of a plant food processing residue, a polyolefin, a modified polyolefin and an additive optionally used is dried under a dry condition, that is, in the absence of a solvent in a temperature range of 120 to 190 ° C. While mechanical energy is applied and crushed , the mechanochemical reaction is virtually eliminated.
Process until the composite is completed by the response. Mechanical energy at this time is given by mechanical means such as crushing, impact, and friction. Here, "complexing is substantially completed" means that the plant food processing residue loses its original physical properties and becomes in a state of exhibiting lubricity as a whole.

In this way, the mechanochemical reaction proceeds by applying mechanical energy, and the polyolefin and the modified polyolefin react with each other at the molecular level in the form of fine particles of the plant food processing residue and are dispersed to each other to form a composite. Form the body. Therefore, when this is heat molded,
It is possible to obtain a molded product having a smooth surface with few irregularities. And, the plant food processing residue itself in these molded bodies does not have stretchability, but since they are uniformly dispersed,
Shows high stretchability as a whole.

Next, with reference to the attached drawings, a method for producing the plant food processing composite molding material of the present invention will be described. Figure 1
It is process drawing which shows one example of this method. Here, the plant food processing residue used as a raw material, for example, okara, is usually
Immediately after being discharged from the processing step, since it contains a relatively large amount of water, it needs to be dried. In this case, in order to avoid foaming during the molding process, it is preferable to dry the water content to 10% by mass or less. This drying is hot air drying,
It is performed by vacuum drying, reduced pressure drying, or the like.

Next, in the case where the vegetable food processing residue is a relatively large lump, the dried processing residue has a particle size of 1 mm, preferably 5 in order to shorten the subsequent complexing time.
The powder is pulverized to a particle size of not more than 00 μm. At this time, if the pulverization process is performed using an open type high speed mixer, the temperature rises during the pulverization, so that the drying can be performed simultaneously.

When the vegetable food processing residue contains an oil component, it cannot be removed by ordinary drying. Therefore, if necessary, it may be extracted and washed with an organic solvent such as methyl alcohol or ethyl alcohol to be defatted. However, since the oil component generally plays a role as a plasticizer during compounding or molding, it is not always necessary to remove it.

A polyolefin and a modified polyolefin are blended in a predetermined ratio to the plant food residue powder thus treated. The polyolefin and the modified polyolefin are mixed in advance so that they can be efficiently combined in a short time. Particle size 1m using a cutting mill
It is preferable to make the powder into m or less.

The mixture of the plant food processing residue thus obtained and the polyolefin and the modified polyolefin is then complexed under dry conditions, that is, in the absence of a solvent, while applying mechanical energy. This mechanical energy can be applied by a mechanical milling process, usually using a ball mill, roll mill, jet mill, attrition mill or high speed mixer. At this time, since the temperature rises to 120 to 190 ° C. with the pulverization process, the compounding is completed while maintaining this temperature range. The time required for this compounding depends on the temperature and the amount of mechanical energy applied at that time, but is usually in the range of 40 to 100 minutes.

The composite thus obtained was then converted to 100
After cooling to below ℃, knead, extrude and pelletize. By pelletizing in this manner, transportation to the subsequent molding step can be facilitated. The composite pellets thus obtained can be molded into a molded article such as a sheet or a bottle by press molding, extrusion molding, or injection molding in the same manner as a general plastic molding material.

[0023]

EFFECTS OF THE INVENTION According to the present invention, processing residue of plant foods such as okara, bran and oil cake, which has been disposed of as an unused waste except a part, is combined with a polyolefin and a modified polyolefin. Since it can be reused as a molding material like general thermoplastic resins, it is possible to provide a technique useful as one of the resource recycling industries.

[0024]

The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

Example 1 Okara discharged in the process of producing tofu as a food residue was dried using a hot air dryer until the water content became 10% by mass or less. Next, this dried okara was crushed using a cutting mill to obtain a powder having a particle size of 200 μm or less. The obtained dry powdery okara was immersed in methyl alcohol having a volume ratio of 2 times, and the oil was washed and removed to degrease. Next, after squeezing the methyl alcohol and air-drying to remove most of it,
It was thoroughly dried with a hot air dryer. Then, this was pulverized using a cutting mill to obtain a powder having a particle size of 250 μm or less.

20% by mass of powdered polyethylene and 5% by mass of powdered maleic anhydride-grafted polypropylene were blended with the powdered okara, and the mixture was put into a grinding container and ground for 60 minutes using a ball mill. The produced okara-polyethylene-maleic anhydride grafted polypropylene composite and powdered polyethylene, powdered polypropylene and modified polypropylene with respect to this composite, the final ratio of each component is 20% by weight okara,
Polyethylene 10% by mass, polypropylene 65% by mass,
The modified polypropylene was added to the kneader in an amount of 5% by mass, and melt-kneaded by heating at 190 ° C. for 5 minutes.

The obtained okara-polyethylene-maleic anhydride grafted polypropylene composite was molded into pellets of about 5 mm by using a cutting pelletizer. The composite pellet thus obtained is
It was filled in an m-square square mold and press-molded at 180 ° C. for 2 minutes using a heat press molding machine to obtain a plate-shaped body. The plate-like body thus obtained was uniform and smooth, and no separation of constituent components or formation of lumps was observed.

Comparative Example 1 For comparison, Example 1 was performed without ball milling operation.
Okara, polyethylene, polypropylene, and maleic anhydride-grafted polypropylene were directly added to the kneader at the same composition ratio as in the example described in 1. to produce a plate-like body. Pretreatment such as degreasing of each component, kneading and molding conditions are the same as in Example 1.
The same as in the case of. In the obtained plate-shaped body, massive okara was unevenly scattered, and irregularities were observed on the surface. Table 1 shows the results of punching the plate-shaped bodies manufactured in Example 1 and Comparative Example 1 into a predetermined shape and performing a tensile strength test. In the plate-shaped body obtained by the ball milling process, the strength was improved by 8% and the elongation at break was improved by 35%.

[0029]

[Table 1]

Example 2 The mass ratio of Okara to polypropylene was 3: 2,
Maleic anhydride-grafted polypropylene was mixed so as to be 5% by mass of the total amount, and ball milling, kneading, pelletizing and heat compression molding were carried out under the same conditions as in the example described in Example 1 to obtain an okara. A polypropylene-maleic anhydride grafted polypropylene composite plate was produced. The obtained plate-like body was uniform, no lump of okara was observed, and the surface was smooth.

Comparative Example 2 For the purpose of comparison, Okara,
The polypropylene and the maleic anhydride grafted polypropylene were mixed in the same ratio as in the example described in Example 2, and the mixture was directly put into a kneader to carry out the same operation to produce a plate-shaped body. In the obtained plate-shaped body, massive okara was unevenly scattered, and many irregularities were observed on the surface.

Comparative Example 3 For comparison, maleic anhydride-grafted polypropylene was not added, and the ratio of okara and polypropylene was mixed at the same mass ratio of 3: 2 as in the example described in Example 2 and the same. Were pulverized, kneaded, and pelletized to produce a plate-shaped body. In the obtained plate-shaped body, massive okara was unevenly scattered, and many irregularities were observed on the surface. Table 2 shows the results of punching the plate-shaped bodies manufactured in Example 2 and Comparative Examples 2 and 3 into a predetermined shape and performing a tensile strength test.
When the maleic anhydride grafted polypropylene was added, the plate-like body produced without ball milling had a 70% increase in strength but a 55% decrease in elongation. However, when maleic anhydride-grafted polypropylene was added and ball milling was also performed, the strength of the plate-shaped body was improved by 102% as compared with the case where no addition and no milling were performed. Further, when pulverized, the elongation due to the addition of maleic anhydride grafted polypropylene was improved by 33% as compared with the case where the maleic anhydride grafted polypropylene was not added and pulverized.

[0033]

[Table 2]

[Brief description of drawings]

FIG. 1 is a process drawing of the method of the present invention.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C08L 23/00 C08L 23/26 23/26 99/00 99/00 B65D 1/00 A (72) Inventor Gen Takeuchi Sakaide, Kagawa Prefecture Maruzen Kogyo Co., Ltd. 1826-8 Otomi-cho, Ichi (72) Inventor Takashi Endo 2217-14 Hayashi-cho, Takamatsu-shi, Kagawa Inside Shikoku Institute of Industrial Technology (56) Reference JP-A-11-138622 (JP, 138622) A) JP 8-231763 (JP, A) JP 2000-70914 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C08J 3/20 B09B 3/00 B65D 1 / 09 C08J 5/18 C08L 1/00-101/16

Claims (8)

(57) [Claims] 1. A vegetable food processing residue , polyolefin and
And a mixture of maleic acid or maleic anhydride modified polyolefin at 120 to 190 ° C. under dry conditions.
Mechanochemical reaction is performed while crushing by adding mechanical energy.
A method for producing a composite molding material for a plant food processing residue , which comprises subjecting the composition to a composite treatment. 2. Per 100 parts by mass of a vegetable food processing residue,
10 to 70 parts by weight of polyolefin, the production of vegetable food processing left composite molding material <br/> claim 1, wherein the use of 2 to 50 parts by weight of maleic acid or maleic anhydride-modified polyolefin
Way . 3. The method for producing a vegetable food processing residue composite molding material according to claim 1 or 2, wherein the vegetable food processing residue is okara obtained during the production of tofu. 4. The polyolefin as claimed in claim 1, which is polyethylene, polypropylene or a mixture thereof.
Or a method for producing a composite molding material for plant food processing residue according to 3
Law . 5. A process for producing a composite molding material for a vegetable food processing residue according to claim 1, wherein the polyolefin modified with maleic acid or maleic anhydride is a polyolefin graft-copolymerized with maleic acid or maleic anhydride .
Build method . 6. The method according to any one of claims 1 to 5.
A method for producing a molded article, which comprises heat-molding the plant-food-processed residue composite molding material obtained by the method by press molding, extrusion molding, or injection molding. 7. The method for producing a molded body according to claim 6 , wherein the molded body is a sheet. 8. The method for producing a molded body according to claim 6 , wherein the molded body is a bottle.