Marine bioresin composition, bioresin film, and method for producing bioresin film

Abstract

To provide a technique for providing a resin film product which is excellent in productivity, can make an organism-derived resource uniformly and much contained in a resin product, for example, exhibits a high biomass degree, is thin and exhibits a sufficient strength, and is usable as "plastic shopping bag" and "garbage bag".SOLUTION: An oceanic bio-resin composition contains an organism-derived component, a polyolefin-based resin component and a reinforcing agent, in which the organism-derived component is an oceanic organism-derived component nano-level miniaturized to 30 μm or less, a ratio of the oceanic organism-derived component in the solid content is 25 mass% or more, and the reinforcing agent has reinforcing agent particles nano-level miniaturized to 1 nm to 1,000 nm.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a marine bioresin composition, a bioresin film using the composition as a raw material, and a method for producing a bioresin film, and more specifically, to a technology that enables the provision of a bioresin film containing components derived from marine organisms and having a high biomass ratio of 25% or more, for example, products such as "plastic shopping bags" and "garbage bags" that use the film. Plastic shopping bags are required to meet the standards of the Food Sanitation Act, and in recent years, it has been pointed out that "plastic shopping bags" and "garbage bags" are a cause of marine pollution, so it is desired that they be easily decomposable in the event of illegal dumping, etc., and the present invention relates to a technology that enables the provision of products that take such points into consideration. [Background technology]

[0002] In recent years, biological resources (biomass) other than fossil resources have been attracting attention as a non-exhaustible industrial resource. In particular, plants grow by absorbing CO2 from the atmosphere through photosynthesis using sunlight as energy, so products made from biological raw materials are thought to have no effect on the increase or decrease of CO2 in the atmosphere (carbon neutral) because the amount of CO2 absorbed by photosynthesis during the plant's growth process is offset by the amount of CO2 emitted when the plant is burned. There is hope for the development of such products, and a variety of such products are being offered. Among products using biological raw materials, the development and use of biomass mark certified products, which will be described later, is desirable because they are safe, contribute to the formation of a recycling-oriented society, and are useful in preventing global warming.

[0003] One of the representative technologies that utilizes the above-mentioned plant-derived raw materials and commercializes them is biopolyethylene. In this technology, the residual liquid after extracting sugar from sugarcane juice is fermented to produce bioethanol, and the bioethylene extracted from the fermentation is used as the basic raw material for biopolyethylene. For example, Patent Document 1 proposes the provision of a single-layer sealant film made of a plant-derived polyethylene resin with a high biomass content. In addition, various proposals have been made to obtain resins using plant-derived raw materials. For example, although not for use in resin films, it has been proposed to obtain a biopolyurethane resin using a plant-derived diol component and a plant-derived dicarboxylic acid component (Patent Document 2).

[0004] On the other hand, as a technology for effectively utilizing biological resources, it is known that plant-derived resources such as finely powdered waste paper or rice husk powder are incorporated into the resin component (see Patent Documents 2 and 3), and this technology is also being implemented. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6614203 [Patent Document 2] JP 2019-172977 A [Patent Document 3] Patent No. 2904770 [Patent Document 4] JP 2002-235013 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the conventional technology using the above-mentioned plant-derived bioethylene and bioethanol as the basic raw material for resin is useful and can produce products with a high plant content, but has the problem that the productivity of the basic raw material is poor and it is not suitable for products that are consumed in large quantities. In addition, the conventional technology using biological resources such as waste paper and rice husks has the problem that it is difficult to uniformly and in large amounts contain these resources in the resin, and it is particularly difficult to obtain products with a high biomass content in thin resin films and resin sheets.

[0007] In response to the above, for example, measures have been taken in recent years to restrict the use of so-called "plastic shopping bags" other than those with a high biomass content, as they are considered to be a cause of environmental destruction. Products such as "plastic shopping bags" and "garbage bags" must be available in large quantities, and it is desirable to be able to provide them as cheaply as possible, so the issue of cost is extremely important. In addition to the above issues, "plastic shopping bags" and "garbage bags" are required to be as light as possible in themselves due to their uses, and to have strength sufficient to withstand a considerable load generated by the products stored in the bag and not easily ripped or broken by the products of various shapes stored in the bag. Furthermore, in the case of "plastic shopping bags," since they are used to put food, they are required to meet the packaging standards of the Food Sanitation Act, and since it has been pointed out in recent years that "plastic shopping bags" and "garbage bags" are a cause of marine pollution, it is desirable that they be made of materials that decompose easily when illegally dumped.

[0008] Therefore, the object of the present invention is to establish a technology that can provide a resin film product that is highly productive and can uniformly and in large amounts contain biological resources in a resin product, for example, a resin film product that has a high biomass content and is thin and has sufficient strength. More specifically, the object of the present invention is to establish a technology that can provide a bioresin film that can achieve a high biomass content and has sufficient strength, for example, and can be used as a "plastic shopping bag" or "garbage bag", at a low cost. Furthermore, the object of the present invention is to provide a bioresin film that meets the packaging standards of the Food Sanitation Act required for "plastic shopping bags" and the like, and that can contribute to the prevention of marine pollution problems by being easily decomposable compared to conventional products. [Means for solving the problem]

[0009] The above object can be achieved by the present invention, which provides the following marine bio-resin composition. [1] A marine bio-resin composition comprising a biological component, a polyolefin resin component, and a reinforcing agent, the biological component being a component derived from marine organisms nano-sized to 30 μm or less, the proportion of the marine organism-derived component in the solid content being 25 mass% or more, and the reinforcing agent having reinforcing agent particles nano-sized to 1 nm to 1000 nm.

[0010] Preferred examples of the marine bio-resin composition include the following. [2] The marine bio-resin composition according to [1] above, wherein the particles constituting the reinforcing agent are at least one selected from the group consisting of metal oxides, metal complexes, cellulose nanofibers and silicones. [3] The marine bioresin composition according to [1] or [2] above, wherein the polyolefin resin component is polyethylene or polypropylene. [4] The marine bioresin composition according to any one of [1] to [3] above, wherein the main raw material of the component derived from marine organisms is seashells and crustacean shells.

[0011] As another embodiment, the present invention provides a bio-resin film as described below. [5] A marine bioresin film made from the marine bioresin composition described in any one of [1] to [4] above as a raw material, having a thickness of 8 μm or more and 50 μm or less, and a biomass content of 25% or more.

[0012] As another embodiment, the present invention provides a method for producing a bio-resin film as described below. [6] A method for producing a bioresin film containing a marine organism-derived component and having a thickness of 8 μm or more and 50 μm or less, comprising the steps of: The raw materials used are a master batch containing marine organism-derived components, which is a polyolefin resin component containing marine organism-derived components nano-sized to 30 μm or less, A reinforcing agent-containing master batch containing a reinforcing agent having reinforcing agent particles that have been nano-sized to 1 nm to 1000 nm, A method for producing a bioresin film containing components derived from marine organisms, comprising blending at least a master batch containing components derived from marine organisms and a master batch containing a reinforcing agent with a base polyolefin resin, designing the blend containing these so that the content of the components derived from marine organisms in the blend is 25% or more by mass, and using the blend to obtain a film-like molded product having a thickness of 8 μm or more and 50 μm or less.

[0013] A preferred embodiment of the method for producing a bioresin film of the present invention is as follows. [7] The method for producing a bio-resin film containing a marine organism-derived component described in [6] above, wherein the amount of the reinforcing agent-containing master batch in the composition is 2.5 to 3.5 parts by mass per 100 parts of the composition. Effect of the Invention

[0014] According to the present invention, a technology is realized that can provide a resin film product that is inexpensive, has a high biomass degree of 25% or more, is thin, and has a satisfactory strength. More specifically, according to the present invention, a marine bioresin composition is provided that enables the provision of a bioresin film that has a high biomass degree of 25% or more, and can provide a product that can be used in the same way as before, such as a "shopping bag" or a "garbage bag". In addition, according to the marine bioresin composition of the present invention, the amount of resin required to obtain a product having the same strength as before is less than the amount of resin used to obtain a conventional product, so that a product using the bioresin film of the present invention is environmentally friendly in that it uses biological resources and can reduce the amount of resin used. In addition, the resin film obtained by the marine bioresin composition of the present invention forms a "shopping bag" that meets the packaging standards of the Food Sanitation Act. Furthermore, since the resin film obtained by the marine bioresin composition of the present invention contains a large amount of components derived from marine organisms, is thin, and has a small resin content, it is expected that the decomposition property will be improved compared to conventional resin film products when dumped into the ocean. In addition, since much of what decomposes and is released into the ocean is derived from marine organisms, this will contribute to reducing the problem of marine pollution. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will be described below with reference to the embodiments, but the present invention is not limited to the embodiments. The present inventors recognized that, as a means for improving the biomass content of products such as mass-produced "shopping bags" and "garbage bags," a method of including a finely divided powdered material obtained using a biological resource in a resin component is more useful than a method of using a biological component such as biopolyethylene or bioethanol as a reactive component when synthesizing a resin as a raw material for the product. Furthermore, the present inventors have conventionally used plant-derived materials such as waste paper and rice husks as biomaterials to be mixed into the resin, but have found the usefulness of using a component derived from marine organisms and have arrived at the present invention. That is, the conventionally used plant-derived materials include waste paper, which can be finely divided by crushing, but is too light and difficult to be uniformly and in large amounts in the resin, and rice husks, which is difficult to finely divide.

[0016] In contrast to the above, micronized materials derived from marine organisms have the advantage of being used in many fields and available in large quantities at low cost. For example, products made from finely ground scallop shells are commercially available and are used for various purposes. There are also products made from finely ground oyster shells, crab shells, and shrimp shells. Unlike rice shells, which are plant-derived components of conventional technology, shells and crustacean shells derived from marine organisms are also being micronized to the nano level. For example, efforts are being made to effectively utilize and recycle scallop shells, which are discarded in large quantities, and a technology has been developed to nano-pulverize scallop shells into nanoparticles. And, since nanoparticleization makes it possible to use them as functional materials, it is expected that they will be used in a wider variety of fields (see JP 2016-10753 A).

[0017] The marine bioresin composition of the present invention may be composed of marine organism-derived components finely divided to 30 μm or less. For example, since resources such as scallop shells are available in large quantities, inexpensive materials can be easily obtained and are useful as materials for mass-produced products. The marine organism-derived components constituting the present invention are preferably classified and adjusted to a particle size of 30 μm or less, preferably 10 μm or less. According to the inventors' studies, it is possible to obtain a more effective bioresin film by using a material finely divided to about 1 μm. According to the inventors' studies, by using the above-mentioned finely divided marine organism-derived components, the components are uniformly mixed with the base polyolefin resin component, and when a bioresin film is produced using the marine bioresin composition of the present invention, a white or light-colored opaque film can be easily obtained, depending on the degree of fine division of the marine organism-derived components used.

[0018] Furthermore, the finely ground material derived from marine organisms as described above can be easily pelletized by mixing it with resin. It is known that shells contain about 95% inorganic components (calcium carbonate) and 5% organic components acting as a binder, which is also considered to be the reason why the shells can be easily pelletized with resin. In the method for producing a bioresin film of the present invention, when producing a bioresin film containing a component derived from marine organisms, a master batch containing a component derived from marine organisms is used to adjust the content of the component derived from marine organisms contained in the film to 25% or more. For this reason, it is preferable to use the same resin as the polyolefin resin used as the base when producing the master batch containing a component derived from marine organisms.

[0019] The polyolefin resin component constituting the present invention is the base raw material of the marine bioresin composition and marine bioresin film of the present invention. The polyolefin resin constituting the present invention may be a polyethylene resin or a polypropylene resin, depending on the application. For example, in products such as the above-mentioned "plastic shopping bags" and "garbage bags," a general-purpose and inexpensive polyethylene resin is used as in the past.

[0020] The technical feature of the present invention is that the above-mentioned base polyolefin resin component contains a reinforcing agent for imparting strength to the film when the film is produced, together with the marine organism-derived component. In addition, both the marine organism-derived component and the marine organism-derived component are finely divided and contained. The degree of fineness of the marine organism-derived component is as described above. First, according to the study by the present inventors, when a resin film is produced from a material in which the above-mentioned marine organism-derived component that has been nano-fine-divided to 30 μm or less is mixed with the polyolefin resin component, even if the proportion of the marine organism-derived component in the solid content is 25% by mass or more, or even 30% by mass or more, it is possible to easily produce a polyolefin resin film in which the finely divided component is uniformly contained, compared to the case of using conventional plant-derived resources. However, in this case, it was found that the obtained resin film has poor strength and cannot be used for products such as "shopping bags" and "garbage bags". Specifically, when the resin film obtained by the above-mentioned method is pulled by hand, it easily stretches in the direction of pulling, and when pulled further, the film easily tears.

[0021] The present inventors have intensively studied to solve this problem, and have arrived at the present invention. That is, according to the configuration of the present invention, it is possible to obtain a bioresin film that is in a uniform state in which finely divided marine organism-derived components are uniformly contained, and that has sufficient strength to be used in products such as "shopping bags" and "garbage bags". In order to solve the above problem, the present inventors have studied the use of a reinforcing agent in combination with the raw material. As a result, it has been found that it is effective to use at least one selected from the group consisting of metal oxides such as iron oxide, titanium oxide, zinc oxide, and alumina, metal complexes, cellulose nanofibers, and silicone as a reinforcing agent in combination. Examples of metal complexes include ammine complexes, cyano complexes, halogeno complexes, and hydroxy complexes, as well as metal complexes used as dyes, enzymes, and various functional materials. Examples of metals constituting metal complexes include copper, iron, and aluminum.

[0022] Furthermore, the present inventors have found that when obtaining the bioresin film of the present invention, it is important to use the above-mentioned reinforcing agent in a configuration having reinforcing agent particles nano-fine-sized to 1 nm to 1000 nm. It has also been found that it is more effective to use a reinforcing agent nano-fine-sized to about 20 nm to 50 nm. When the above-mentioned fine iron oxide or the like is used as the reinforcing agent, as can be confirmed from the fact that the obtained bioresin film is lightly colored, the fine reinforcing agent is considered to be in a state in which it stably coexists with the fine marine organism-derived component in the structure of the polyolefin-based bioresin film, which is a crystalline plastic having a crystalline portion. That is, the reinforcing agent used in the present invention does not function as a catalyst, such as the metallocene complexes conventionally used in polyolefin-based resins, but is considered to have some effect on the crystallinity of the resin by being present in the structure of the bioresin film having a crystalline portion, and as a result, it is considered that the fine marine organism-derived component can stably coexist in a state in which it is fixed to the resin component. The effect of expressing the strength in the bioresin film of the present invention was first obtained by nano-fine-sizing the reinforcing agent as specified in the present invention, so the reinforcing agent constituting the present invention does not function as a catalyst. Furthermore, the inventors believe that the coexistence of the two, as described above, affects the crystallinity of the resin component, thereby achieving the remarkable effect of improving the strength of the resin film of the present invention.

[0023] According to the study by the present inventors, in order to produce the polyolefin-based bioresin film of the present invention by a simpler method, it is effective to use a masterbatch containing a reinforcing agent having reinforcing agent particles nano-fine-sized to 1 nm to 1000 nm, preferably about 20 nm to 50 nm. Here, according to the study by the present inventors, it was found that the amount of the reinforcing agent constituting the present invention is small, and it is possible to prepare a polyolefin-based bioresin film that is economical in terms of raw material costs. Specifically, the amount of the reinforcing agent-containing masterbatch in the blend containing the polyolefin-based resin component, the component derived from marine organisms, and the reinforcing agent may be about 2.5 to 3.5 parts by mass in 100 parts of the blend. Here, the amount of the reinforcing agent in the masterbatch containing the reinforcing agent is about 0.02 to 0.03%, so the amount of the reinforcing agent coexisting in the structure of the bioresin film is extremely small. From this perspective, the marine bioresin composition of the present invention is useful as a versatile material technology since it allows for low material costs.

[0024] According to the study by the present inventors, a marine organism-derived component-containing master batch in which a polyolefin resin component is mixed with a marine organism-derived component pulverized to 30 μm or less, and a reinforcing agent-containing master batch in which a reinforcing agent having reinforcing agent particles pulverized to 1 nm to 1000 nm is contained in the manufacturing raw material are used, and the marine organism-derived component-containing master batch and the reinforcing agent-containing master batch are mixed with a base polyolefin resin, and the content of the marine organism-derived component in the mixture containing these is designed to be 25% or more by mass, thereby making it possible to obtain a bioresin film in which the micronized marine organism-derived component is uniformly contained. The marine bioresin film of the present invention obtained in this way is characterized by having a thickness of 8 μm or more and 50 μm or less, and a biomass degree of 25% or more.

[0025] It was also confirmed that when the bio-resin film obtained using the marine bio-resin composition of the present invention is used to manufacture, for example, "plastic shopping bags" or "garbage bags" of similar shapes by a conventional method, a product that is sufficiently usable as a "plastic shopping bag" or "garbage bag" can be obtained. Specifically, for example, when a product is placed in the obtained "plastic shopping bag" and the bag is transported under a load, the film does not stretch or tear, and the bag can be used as a "plastic shopping bag."

[0026] Even more surprisingly, it was found that the thickness of the bioresin film obtained using the marine bioresin composition of the present invention can be made thinner than that of conventional "plastic shopping bags" and "garbage bags". Specifically, conventional "plastic shopping bags" and "garbage bags" generally have a thickness of about 12 to 18 μm, but by using the bioresin film of the present invention, the thickness can be reduced to about 8 to 10 μm. In other words, the technology of the present invention uses components derived from marine organisms as raw materials, and can also significantly reduce the amount of resin used in the manufacture of products, so that it can be expected to make it possible to provide environmentally friendly products in this respect as well. EXAMPLES

[0027] Hereinafter, further specific examples of the above-mentioned embodiment will be described with reference to examples and comparative examples, but the present invention is not limited to the following examples. Parts and % are by weight unless otherwise specified.

[0028] [Example 1] As the base resin, polyethylene pellets used in the manufacture of conventional "plastic shopping bags" were used. As the marine organism-derived component, scallop shells were finely divided into particles under 30 μm and pelletized with polyethylene. The content of finely pulverized scallop shells in the pellets was 76.5%. As the reinforcing agent, polyethylene pellets containing about 0.02% of nano-fine iron oxide of about 20 to 30 nm were used. Then, 57 parts of polyethylene pellets as the base resin, 40 parts of pellets containing marine organism-derived components, and 3 parts of pellets containing a reinforcing agent were used to produce a plastic bag for plastic shopping with a thickness of 10 μm by inflation molding according to the usual method. The calculated biomass degree of this plastic bag was 30.6%.

[0029] [Comparative Example 1] Using 60 parts of the polyethylene pellets used in Example 1 and 40 parts of the pellets containing components derived from marine organisms, plastic bags for shopping malls with a thickness of 30 μm for comparison were produced by inflation molding in the usual manner, as in Example 1. The biomass content of this plastic bag was the same as that of the plastic bags of the Examples.

[0030] [evaluation] The plastic bags of the Examples and Comparative Examples obtained above were evaluated for appearance and strength as follows. (exterior) The plastic bags of the Example and Comparative Example were visually observed, and as a result, both were white and opaque, and no difference between them could be visually observed.

[0031] (strength) The strength of the plastic bags of the Example and Comparative Example was checked by pulling them in each direction with both hands. As a result, the plastic bag of the Comparative Example was easily stretched with a small force when pulled in one direction, and eventually tore or developed a hole in the direction perpendicular to the stretching direction when the force was continued. Also, when pulled in the direction perpendicular to the stretching direction, it was easily torn and fell into a tattered state.

[0032] On the other hand, the plastic bag of the Example did not tear, unlike the plastic bag of the Comparative Example, even when pulled with a considerable force. In addition, it stretched when pulled with a stronger force than the Comparative Example, but it was confirmed that the stretching was significantly suppressed. When two 1L bottles of milk and packs of lettuce, cabbage, and tomatoes were placed in the plastic bag of the Example and transported, it was confirmed that it could be transported in good condition and could be used as a shopping bag.

Claims

1. A marine bio-resin composition comprising a biological component, a polyolefin resin component, and a reinforcing agent, wherein the biological component is a component derived from marine organisms that has been nano-sized to 30 μm or less, the component derived from marine organisms being finely ground shells and / or crustacean shells, the proportion of the component derived from marine organisms in the solid content being 25 mass% or more, and the reinforcing agent has reinforcing agent particles that have been nano-sized to 1 nm to 50 nm, and the reinforcing agent particles include iron oxide particles.

2. The marine bio-resin composition according to claim 1, further comprising, as the reinforcing agent particles, at least one particle selected from the group consisting of metal oxide particles other than the iron oxide particles, metal complexes, cellulose nanofibers, and silicones.

3. 3. The marine bioresin composition according to claim 1, wherein the polyolefin resin component is polyethylene or polypropylene.

4. The marine bioresin composition according to any one of claims 1 to 3, wherein the main raw material of the component derived from marine organisms is seashells and crustacean shells.

5. A marine bioresin film made from the marine bioresin composition according to any one of claims 1 to 4, having a thickness of 8 μm or more and 50 μm or less, and a biomass ratio of 25% or more.

6. A method for producing a bioresin film containing a marine organism-derived component having a thickness of 8 μm or more and 50 μm or less according to claim 5, A master batch containing a component derived from a marine organism, the master batch being a polyolefin resin component containing finely ground shells and / or crustacean shells nano-refined to 30 μm or less; a reinforcing agent-containing master batch containing a reinforcing agent having reinforcing agent particles that have been nano-refined to 1 nm to 50 nm, the reinforcing agent particles including iron oxide particles; A method for producing a bioresin film containing components derived from marine organisms, comprising blending at least a master batch containing components derived from marine organisms and a master batch containing a reinforcing agent with a base polyolefin resin, designing the blend containing these so that the content of the components derived from marine organisms in the blend is 25% or more by mass, and using the blend to obtain a film-like molded product having a thickness of 8 μm or more and 50 μm or less.

7. The amount of the reinforcing agent-containing master batch in the formulation is 2.5 to 3.5 parts by mass per 100 parts of the formulation. The method for producing a bioresin film containing a marine organism-derived component according to claim 6.