Biodegradable plastic product containing wheat bran.

Abstract

The invention relates to a bioplastic composition containing wheat bran which is a food byproduct and a bioplastic pellet / film using such composition. More specifically, the invention relates to a bioplastic composition containing wheat bran and a bioplastic film using such composition such that the properties of the composition are enhanced to protect the improved properties of the bioplastic film prepared from it, thereby having the effect of reducing carbon emissions and providing a substitute for conventional petroleum-based bioplastic products.

Description

Bioplastic composition containing wheat bran and bioplastic film using the same The present invention relates to a bioplastic composition containing wheat bran, a food byproduct, and bioplastic pellets and films using the same. The invention relates to a bioplastic composition containing wheat bran and bioplastic films using the same, which can replace existing petroleum-derived plastic products while enabling carbon reduction, as the physical properties of the composition are improved and the physical properties of the bioplastic films produced thereby are also improved. Plastic is a polymer material with a large molecular weight. As the molecular weight increases, it changes from a gaseous state to a liquid and then to a solid. In solid materials, while fluidity decreases with increasing molecular weight, mechanical properties and heat resistance improve, allowing it to be used as a material necessary for daily life, similar to metals, wood, ceramics, and rubber. Plastic is produced by molding and processing this polymer material by adding various modifiers, colorants, reinforcing agents, and fillers. Although the properties of plastic are determined by the chemical structure of synthetic resins such as PE, PP, and PVC, properties can change even within the same resin due to many factors, which can be utilized to modify it. Regarding chemical structure, properties vary depending on molecular weight, molecular weight distribution, the state of the main chain and side chains determined by polymerization conditions, end groups, bridging, stereoregularity, and the compositional distribution of the copolymer. Generally, the process of preparing a composition suitable for a specific purpose by adding various blending agents, such as additives, reinforcing agents, and modifiers, to polymer raw materials is called compounding, and the resulting products are distributed in the form of pellets. Recently, the amount of plastic waste has been increasing exponentially due to the rising use of various plastics, including films used for food packaging. Generally, plastic waste is disposed of through landfilling, incineration, or recycling. However, incinerating or landfilling waste from petroleum-derived plastic products generates toxic gases, causing air pollution and contributing to a shortage of landfill space and environmental contamination. Therefore, to address these issues, active research and development is underway for eco-friendly plastics capable of carbon reduction by utilizing plant-derived byproducts or natural raw materials produced through fermentation technology. However, while using plant-derived byproducts instead of petroleum-derived materials in the development of plastic compositions offers carbon reduction benefits by reducing the content of petroleum-based plastic materials, it presents a problem where physical properties such as elongation and tensile strength deteriorate compared to conventional plastic compositions. In this regard, Korean Patent Publication No. 10-2014-0018004 discloses a composition for sheets using biomass, Korean Patent Publication No. 10-2014-0094865 discloses a composition for biomass films, and Korean Patent Publication No. 10-2013-0051840 discloses eco-friendly bio-based pellets using plant biomass; however, there has been no disclosure regarding a bioplastic composition using wheat bran. [Prior Art Literature] [Patent Literature] (Patent Document 1) Korean Published Patent Application No. 10-2014-0018004 (Date of publication: August 26, 2015) (Patent Document 2) Korean Published Patent Application No. 10-2014-0094865 (Publication Date: July 31, 2015) (Patent Document 3) Korean Published Patent Application No. 10-2013-0051840 (Date of publication: May 21, 2013) The present invention aims to provide a bioplastic composition comprising wheat bran containing a polyolefin resin, wheat bran, wax, an inorganic filler, and a surfactant in order to provide a bioplastic composition comprising wheat bran. In addition, the present invention aims to provide bioplastic pellets and films comprising the bioplastic composition described above. To solve the above problem, the present invention provides a bioplastic composition comprising wheat bran containing a polyolefin resin, wheat bran, wax, an inorganic filler, and a surfactant. The above polyolefin resin may be one or more selected from polyethylene (PE), polypropylene (PP), polybutylene, and polymethylpentene. The polyolefin resin in the above composition may be included in an amount of 40 to 70 weight% in the above composition. Meanwhile, the size of the wheat bran may be 5 to 30 μm, the uniformity of the wheat bran size (PDI) may be 2 or less, and the moisture content of the wheat bran may be 1 to 10%. In addition, the wheat bran may be included in the composition at a weight of 10 to 30%. Meanwhile, the above wax is one or more selected from paraffin wax, liquid paraffin wax, beeswax, molda wax, candelilla wax, polyethylene wax, and polypropylene wax, and may be included in the composition in an amount of 10 to 20 weight percent. In addition, the inorganic filler is one or more selected from the group consisting of calcium carbonate, silica, mica, and talc, and may be included in the composition in an amount of 5 to 20 weight percent. In addition, the surfactant may be one or more selected from fatty acids such as stearic acid, myristic acid, palmitic acid, arachidic acid, oleic acid, linolenic acid, and hydrogenated fatty acids, and polyol series such as glycerin, butylene glycol, propylene glycol, dipropylene glycol, pentylene glycol, hexylene glycol, polyethylene glycol, and sorbitol, and may be included in the composition in an amount of 0.5 to 5 weight%. Meanwhile, the above composition may further include 10 to 30 parts by weight of a polyolefin resin per 100 parts by weight of the total composition. In addition, the present invention provides a bioplastic pellet comprising the above-described composition. In addition, the present invention provides a bioplastic film comprising the above-described composition. The film may further comprise a polyolefin-based resin. Meanwhile, the present invention provides a method for manufacturing bioplastic pellets containing wheat bran, comprising the steps of: 1) heating and mixing a polyolefin resin, wheat bran, wax, an inorganic filler, and a surfactant to produce a bioplastic composition containing wheat bran; and 2) extruding and cutting the bioplastic composition containing wheat bran to form pellets. In particular, the above wheat bran may undergo a classification and pulverization process after grinding prior to mixing. The present invention also provides a method for manufacturing a bioplastic film comprising a polyolefin resin in addition to the bioplastic pellets manufactured by the above manufacturing method. The bioplastic composition of the present invention has uniform physical properties and high dispersibility, allowing conventional equipment to be used during film manufacturing, and has the effect of preventing the occurrence of holes during manufacturing. In addition, the bioplastic film of the present invention has physical properties similar to existing plastic-based films, allowing for the use of conventional equipment while providing a bioplastic film capable of carbon reduction. Figure 1 is a flowchart showing the manufacturing process of a pellet containing a bioplastic composition including wheat bran according to the present invention. Figure 2 is a photograph showing holes occurring when manufacturing a film using a composition in which the size of the conventional wheat bran is not uniform. Figure 3 is a photograph showing pellets and films of a bioplastic composition according to wheat bran content. Figure 4 is a graph showing the average volume according to particle diameter when finely ground after crushing and classification. The present invention provides a bioplastic composition comprising wheat bran containing a polyolefin resin, wheat bran, wax, inorganic filler, and other additives. The polyolefin resin of the present invention may be one or more selected from polyethylene (PE), polypropylene (PP), polybutylene, and polymethylpentene, preferably one or more selected from polyethylene (PE) and polypropylene (PP), and most preferably polyethylene (PE). The above polyethylene may be one or more selected from linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), and high-density polyethylene (HDPE). Additionally, the above polyethylene may be produced under one or more catalysts selected from metallocene catalysts and Ziegler-Natta catalysts, but preferably, it may be produced using a metallocene catalyst. Unlike the Ziegler-Natta catalyst, the metallocene catalyst has a single active site, and by precisely controlling the polymer structure using single-active-site catalyst technology, specific synthesis processes can be freely implemented. In particular, M-PE refers to PE synthesized using a metallocene catalyst, and M-PE has superior processability and quality compared to other PEs, resulting in less formation of bubbles or pores. The polyolefin resin in the above composition may be included in an amount of 40 to 70 weight%. If included in an amount less than 40 weight%, mixing of the composition is not easy, pellet processing is not easy, and there are problems with uneven physical properties during film manufacturing. If included in an amount greater than 70 weight%, the natural color of wheat is not maintained in the composition, and the carbon reduction effect becomes negligible. However, the composition of the present invention contains a polyolefin resin within the above range, so the composition maintains the natural color of wheat, does not generate wheat bubbles during film manufacturing, and can provide the same appearance and quality as existing plastic-based films. The wheat bran of the present invention may be a byproduct remaining after flour production among biomass, and specifically, the wheat bran may have undergone grinding, classification, and pulverization processes. The size of the wheat bran may be 5 to 30 μm, preferably 10 to 25 μm. If the wheat bran size is smaller than the above range, the powder will fly away, resulting in poor workability and affecting the yield. If it is larger than the range, the melt index (MI) of the composition increases, causing the hardness of the pellets produced from the composition to be inconsistent. Consequently, when manufacturing a film using this composition, the film processability is low, leading to the occurrence of holes or deviations in film properties (sealing strength, tensile strength, elongation, etc.). In addition, the uniformity of the wheat bran particles is defined by the polydipersity index (PDI). The PDI is expressed as the standard deviation of the diameter divided by the square of the mean of the diameter. In the present invention, the PDI value of the wheat bran may be 2 or less, preferably 1.5 or less. If the uniformity of the wheat size deviates from the above range, the compounding properties may be uneven and dispersibility may be reduced. In the above PDI range, powder smaller than 30㎛ can be formed at about 80%. In addition, the wheat bran may have a moisture content of 1 to 10%. If the moisture content of the wheat bran is lower than the above range, the wheat bran processing process is inefficient, and if it is higher than the range, the physical properties of the manufactured composition are poor and the degree of film processing is low. The above wheat bran may be included in the composition in an amount of 10 to 30 weight percent. If the amount is less than the above range, the unique color of the wheat bran may not be maintained in the composition, and if the amount is more than the above range, fine-sized wheat bran may clump together during the composition manufacturing process and contain air bubbles, which may result in a decrease in the physical properties of the film (sealing strength, tensile strength, elongation, etc.) and cause problems such as the generation of holes during manufacturing. However, the composition of the present invention contains wheat bran within the above range, so the unique color of wheat is maintained, no air bubbles are generated during film manufacturing, and it can provide the same appearance and quality as existing plastic-based films. The wax of the present invention serves to link wheat bran and polyolefin resin and may be one or more selected from paraffin wax, liquid paraffin wax, beeswax, molda wax, candelilla wax, polyethylene wax, and polypropylene wax, but is not limited thereto; however, it is preferable to use polyethylene wax, and more preferably, it is preferable to use a mixture of one or two selected from low-density polyethylene wax (LDPE WAX) and high-density polyethylene wax (HDPE WAX). The wax may be included in the composition at a weight of 10 to 20 percent. The inorganic filler of the present invention may be one or more selected from the group consisting of calcium carbonate, silica, mica, and talc, but is not limited thereto; preferably, it is preferable to use calcium carbonate (CaCO3), which is inexpensive. The inorganic filler may be included in the composition in an amount of 5 to 20 weight percent. If included in an amount less than the above range, physical properties may deteriorate and production costs may increase, and if included in an amount more than the above range, the physical properties of the composition and film may deteriorate. The surfactant of the present invention serves to coat the surface of the wheat bran, enable good mixing with wax or polyolefin, and prevent the wheat bran from burning. It may be one or more selected from fatty acids such as stearic acid, myristic acid, palmitic acid, arachidic acid, oleic acid, linolenic acid, and hydrogenated fatty acids, and polyols such as glycerin, butylene glycol, propylene glycol, dipropylene glycol, pentylene glycol, hexylene glycol, polyethylene glycol, and sorbitol, but is not limited thereto. The surfactant may be included in the composition in an amount of 0.5 to 5 weight%. If the surfactant is less than 0.5 weight%, the effect of the surfactant is negligible, and if it exceeds 5 weight%, a phenomenon in which film properties such as tensile strength deteriorate occurs. The composition of the present invention may further include 10 to 30 parts by weight of a polyolefin resin per 100 parts by weight of the total composition after the composition is prepared. The polyolefin resin may be the same as or different from the polyolefin resin included in the composition, but preferably, using a different one is preferable as it can improve physical properties. If the polyolefin resin within the above range is further included, the physical properties of the film may be improved. The melt index (MI) of the composition of the present invention may be 1.5 to 10. If the melt index (MI) is lower or higher than the above range, the flowability of the composition may be excessively low or high and may not be suitable for extrusion molding. In particular, if the melt index exceeds 10, the composition may become lumpy, making it impossible to produce a film. The present invention can provide a bioplastic pellet comprising the above composition. Pellet containing the above composition may be manufactured by a method for manufacturing bioplastic pellets containing wheat bran, comprising the steps of: 1) preparing a bioplastic composition by heating and mixing a polyolefin resin, wheat bran, wax, an inorganic filler, and a surfactant; and 2) extruding and cutting the bioplastic composition containing wheat bran to form pellets. Specifically, the wheat bran may be prepared by undergoing grinding, classification, and pulverization processes prior to mixing. The grinding process may be performed using a known grinding device, the classification process refers to sorting the ground wheat bran by size, and the pulverization process refers to collecting small-sized wheat bran that has passed through a sieve. Through the above processes, uniformly fine-sized wheat bran can be obtained. Here, the hardness of the pellet containing the above composition may be 94 to 98 or less. The hardness is measured according to JIS-A, and if the pellet is outside the above hardness, the dispersibility decreases and the film processability decreases. The bioplastic composition of the present invention has uniform physical properties and high dispersibility, allowing conventional equipment to be used during film manufacturing, and has the effect of preventing the occurrence of holes during manufacturing. The present invention can provide a bioplastic film comprising the above composition. The above film may have physical properties capable of replacing existing petroleum-derived plastic products. Specifically, the sealing strength of the film may be 0.3 to 1.4 kgf and the puncture strength may be 0.08 to 0.24 kgf. In addition, the elongation of the film may be 300 to 750% in the mechanical direction (MD) and 250 to 900% in the transverse direction (TD), and the tensile strength may be 0.4 to 1.5 kgf in the mechanical direction (MD) and 0.3 to 1.7 kgf in the transverse direction (TD). The above range of physical properties can be used for various packaging applications, such as sack packaging, ton bag liners, and valve bag liners. The bioplastic film of the present invention may be manufactured by mixing and melting the bioplastic composition containing the aforementioned wheat bran, a polyolefin resin, and an additive, and then extruding it using a T-die or calendering. Additionally, a bioplastic film may be manufactured by further including a polyolefin resin in a bioplastic pellet containing wheat bran, which is prepared using the bioplastic composition containing the wheat bran. Specifically, the polyolefin resin may be the same as or different from the polyolefin resin included in the composition, but it is preferable to use a different one as it can improve the physical properties of the film. The bioplastic film of the present invention has physical properties similar to existing plastic-based films, allowing for the use of conventional equipment while enabling carbon reduction. The present invention will be described in more detail in the following examples. Since the examples disclose only one illustration of the present invention, the scope of the present invention is not limited to the scope of the examples. <Example> 1. Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Wheat Bran Size Example 1: Preparation of a composition and film comprising wheat bran powder with a thickness of 15 μm and a PDI of 1 1) Preparation of a bioplastic composition containing wheat bran Wheat bran was automatically dried in an ACM grinder by controlling the blade motor to 100–200 RPM to grind it to a moisture content of 7% or less, and the ground fine particles were classified to produce a powder with a particle size of 15 μm and a PDI of 1 (Fig. 4). In the above range, approximately 90% of the powder is formed to be smaller than 30 μm. A bioplastic composition containing wheat bran was prepared by heating and mixing 25 wt% of wheat bran powder with a particle size of 15 μm and a PDI of 1, 50 wt% of polyethylene in pellet or powder form (LLDPE), 10 wt% of calcium carbonate and 14 wt% of wax as inorganic fillers, and 1 wt% of a surfactant at 160°C–200°C while controlling the temperature so as not to burn the wheat bran, and then extruding and cutting the mixture to process it into pellets. 2) Manufacture of bioplastic films containing wheat bran 20 wt% of the above-mentioned pellets and 80 wt% of a petroleum-based PE blend (70 wt% LLDPE, 10 wt% LDPE) were mixed, and then a 50 μm thick film of Preparation Example 1 was prepared. Comparative Example 1: Preparation of a composition and film comprising wheat bran powder with a thickness of 70 μm and a PDI of 3 In addition to producing and using wheat bran powder with a PDI of 70㎛ and a PDI of 3, a bioplastic composition and film of Comparative Example 1 were prepared using the same manufacturing method as Example 1. Experimental Example 1: Comparison of physical properties of bioplastic films containing wheat bran according to wheat bran peak size To confirm the physical properties of the bioplastic films of Example 1 and Comparative Example 1, tensile strength, elongation, sealing strength, and puncture strength were measured, and the results are shown in Table 1. Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Wheat Bran Size Item Example 1 Comparative Example 1 Wheat Bran Particles (㎛, PDI) 15, 17, 0,3 Thickness (㎛) 50, 50 Tensile Strength (kgf, 15mm) TD 1.0, 10.3, 4MD 1.3, 61.0 Elongation (%) TD 59, 18, 5MD 52, 23, 48 Sealing Strength (kgf) 0.7, 70.66 Piercing Strength (kgf) 0.1, 40.12 As shown in Table 1, it was confirmed that the bioplastic film of Example 1 had higher tensile strength, elongation, sealing strength, and puncture strength compared to the bioplastic film of Comparative Example 1. In other words, it was confirmed that the physical properties of the bioplastic film containing wheat bran are improved when the wheat bran particles are 15 μm and PDI=1. 2. Comparison of Physical Properties of Bioplastic Compositions and Films Containing Wheat Bran According to Wheat Bran Content Examples 2 to 4: Preparation of bioplastic compositions containing wheat bran with different wheat bran contents A bioplastic composition containing wheat bran was prepared by mixing 14% by weight of calcium carbonate and wax and 1% by weight of other additives with 15㎛ and PDI=1 wheat bran powder prepared by the same manufacturing method as in Example 1, in pellet or powder form (LLDPE), and inorganic fillers. The composition was then processed into pellets. The content ratio of wheat bran polyethylene and inorganic fillers in the pellets is as shown in Table 2 below. Comparative Example 2: Preparation of a film not containing wheat bran The composition of Comparative Example 2 was prepared using the same manufacturing method as Examples 2 to 4, except that only polyethylene was used without wheat bran and inorganic fillers, and then processed into pellets. Classification of composition of bioplastic composition containing wheat bran according to wheat bran content Example 2 Example 3 Example 4 Wheat bran content 5% 15% 25% Polyethylene content 70% 60% 50% Inorganic filler 15% 10% 10% Experimental Example 2: Comparison of Physical Properties of Bioplastic Compositions Containing Wheat Bran According to Wheat Bran Content The melt index (MI 190, 2.16 kg), hardness (JIS-A), and specific gravity of the bioplastic compositions or pellets of Examples 2 to 4, which differed only in wheat bran content, and the composition or pellets of Comparative Example 2, which did not contain wheat bran, were measured, and the results are shown in Table 3. Classification of Physical Properties of Bioplastic Compositions Containing Wheat Bran According to Wheat Bran Content Example 2 Example 2 Example 3 Example 4 MI (190℃, 2.16kg) 1.00 1.4 3 1.8 5 2.26 Hardness (JIS-A) 96.5 97.5 97.595~96 Specific Gravity 1.2 13 1.04 41.03 5 1.046 When preparing the compositions of Examples 2 to 4, no black spots occurred and the brown color was maintained. Furthermore, as shown in Table 3, the melt index of the compositions of Examples 2 to 4 showed a tendency to increase as the wheat bran content increased, but all showed values ​​suitable for film manufacturing even when compared to Comparative Example 2, and the hardness of the pellets produced from the compositions also did not show a significant difference from Comparative Example 2. Although the specific gravity was confirmed to be lower than that of Comparative Example 2 due to the inclusion of wheat bran, it showed values ​​suitable for the manufacture of bioplastics containing wheat bran. Examples 5 to 7: Preparation of bioplastic films containing wheat bran according to wheat bran content After mixing 20 wt% of each of the compositions containing wheat bran from Examples 2 to 4 with 80 wt% of petroleum-based PE blending (70 wt% LLDPE, 10 wt% LDPE), films of Examples 5 to 7 with a thickness of 50 μm were prepared. Experimental Example 3: Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Wheat Bran Content The tensile strength, elongation, sealing strength, and puncture strength of the bioplastic films of Examples 5 to 7 were measured, and the results are shown in Table 4. Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Wheat Bran Content Item Example 5 Example 6 Example 7 Wheat Bran Content in Pellet 5% 15% 25% Thickness (㎛) 50 50 50 Tensile Strength (kgf, 15mm) TD 1.6 0 1.0 8 0.6 5 MD 1.4 2 0.8 3 0.4 1 Elongation (%) TD 5 5 2.9 7 4 5 2.7 2 3 18.4 8 MD 6 6 1.7 2 6 13.4 7 3 5 0.7 1 Sealing Strength (kgf) 0.8 8 0.5 9 0.4 0 Piercing Strength (kgf) 0.1 8 0.1 5 0.0 9 During the preparation of the films of Examples 5 to 7, no air bubbles were generated in the wheat, and the physical properties of the composition were uniform and the dispersibility was high, so the thickness variation of the film was prepared within ±2%. As shown in Table 4, it was confirmed that the tensile strength, elongation, sealing strength, and puncture strength of the bioplastic films of Examples 5 to 7 were at a level suitable for packaging. 3. Comparison of Physical Properties of Bioplastic Compositions and Films Containing Wheat Bran According to Polyolefin Resin Examples 8 to 12: Preparation of bioplastic compositions containing wheat bran according to polyolefin resin A composition containing wheat bran was prepared by mixing 1% by weight of polyethylene in pellet or powder form, a catalyst, calcium carbonate as an inorganic filler, wax, and other additives with wheat bran powder prepared by the same manufacturing method as Example 1. The content ratios of wheat bran, polyethylene, inorganic filler, wax, and other additives are as shown in Table 5 below. Classification of composition of bioplastic composition containing wheat bran according to polyolefin resin Example 8 Example 9 Example 10 Example 11 Example 12 Wheat bran content 5% 15% 25% 50% 30% Polyolefin resin 70% 60% 50% 35% 60% Catalyst Metallocene Metallocene Metallocene Metallocene Ziggler-atta Calcium carbonate content 15% 10% 10% 10% 10% Wax 14% 14% 14% 14% 14% Other additives 1% 1% 1% 1% 1% Comparative Examples 3 and 4: Preparation of bioplastic compositions not containing wheat bran Compositions of Comparative Examples 3 (100% polyolefin resin, metallocene catalyst) and 4 (100% polyolefin resin, Ziegler-Natta catalyst) were prepared using only polyethylene and catalysts (metallocene catalyst and Ziegler-Natta catalyst) without wheat bran in the same manufacturing method as Examples 8 to 12. Experimental Example 3: Comparison of Physical Properties of Bioplastic Compositions Containing Wheat Bran According to Polyolefin Resin To determine whether the compositions of Examples 8 to 12, which differed in wheat bran content, polyolefin resin, and catalyst, were suitable for manufacturing bioplastic films, the melt index (MI 190, 2.16 kg) and specific gravity were measured in comparison with the compositions of Comparative Examples 3 and 4, which did not contain wheat bran, and the results are shown in Table 6. Classification of physical properties of bioplastic compositions containing wheat bran according to polyolefin resin Comparative Example 3 Example 8 Example 9 Example 10 Example 11 Comparative Example 4 Example 12 MI (190, 2.16 kg) 1.0 1.4 3 1.8 5 2.2 6 2.3 1.9 4.12 Specific gravity 0.9 2 1 1.0 4 4 1.0 3 5 1.0 4 6 1.0 5 0.9 2 1.0 88 As shown in Table 6, the melt index (MI) showed a tendency to increase as the wheat bran content increased, and it was confirmed that the melt index (MI) was more uniform when using a metallocene catalyst compared to when using a Ziegler-Natta catalyst. However, all compositions of Examples 8 to 12 showed values ​​suitable for film manufacturing. Although the specific gravity of the compositions of Examples 8 to 12 was found to be greater than that of Comparative Examples 3 and 4 due to the inclusion of wheat bran, it showed values ​​suitable for the production of bioplastics containing wheat bran. Examples 13 and 14: Preparation of bioplastic films containing wheat bran according to polyolefin resin A composition containing wheat bran was prepared using the same manufacturing method as in Example 12, using a metallocene catalyst instead of a Ziegler-Natta catalyst, and then pellets were prepared from the composition. Then, 20 wt% of the prepared pellets and 80 wt% of a petroleum-based PE blend (70 wt% LLDPE + 10 wt% LDPE) were mixed, and then bioplastic films of Examples 13 (Hanwha 3305) and 14 (LGSE1020A) with a thickness of 50 μm were prepared. Comparative Example 5: Preparation of a film not containing a bioplastic composition containing wheat bran The film of Comparative Example 5 was prepared by mixing 100 wt% of petroleum-based PE (blanding) (80 wt% LLDPE, 20 wt% LDPE) using the same manufacturing method as in Examples 13 and 14 without a bioplastic composition containing wheat bran. Experimental Example 4: Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Polyolefin Resin To verify the physical properties of the bioplastic films of Examples 13 and 14, the sealing strength was measured, and the results are shown in Table 7. Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran According to Polyolefin Resin Classification Sealing Strength (kgf) Comparison Example 5 1.1368 Example 1 31.0082 Example 1 41.0315 As shown in Table 7, the bioplastic films of Examples 13 and 14 have sealing strength, puncture strength, and elongation rate that are slightly lower than those of Comparative Example 5, but exhibit appropriate values ​​during film processing, thus confirming the effect of providing a bioplastic film capable of carbon reduction while having physical properties similar to existing plastic-based films. 4. Changes in physical properties resulting from the mixing of bioplastic compositions containing wheat bran with other materials Examples 15 to 17: Preparation of bioplastic films containing wheat bran mixed with other materials A bioplastic composition was prepared by additionally mixing 20 parts by weight of LLDPE with 100 parts by weight of the composition containing wheat bran from Example 4, and pellets were prepared from the composition. 20% by weight of the pellets and 80% by weight of a petroleum-based PE blend (70% by weight of LLDPE, 10% by weight of LDPE) were mixed, and then a bioplastic film of Example 15 with a thickness of 50 μm was prepared. Bioplastic films of Examples 16 and 17 were prepared using the same manufacturing method with a composition using 20 parts by weight of LDPE and 20 parts by weight of M-PE instead of LLDPE. Experimental Example 5: Comparison of physical properties of bioplastic films containing wheat bran mixed with other materials To confirm the physical properties of the bioplastic films of Examples 15 to 17, sealing strength, puncture strength, and elongation were measured, and the results are shown in Table 8. Comparison of Physical Properties of Bioplastic Films Containing Wheat Bran Mixed with Other Materials Example 15 Example 16 Example 17 Composition 25% Wheat Bran 100 parts by weight + LLDPE 20 parts by weight 25% Wheat Bran 100 parts by weight + LDPE 20 parts by weight 25% Wheat Bran 100 parts by weight + M-PE 20 parts by weight Thickness (㎛) 50 50 50 Tensile Strength (kgf, 15mm) TD 0.8 9 0.8 8 0.80 MD 0.6 4 0.5 3 0.53 Elongation (%) TD 4 3 1.2 9 2 6 6.2 2 3 4 1.79 MD 4 1 6.0 4 5 3 2.4 7 3 2 4.47 Sealing Strength (kgf) 0.5 7 0.6 4 0.58 Piercing Strength (kgf) 0.1 4 0.1 1 0.12 As shown in Table 8, it was confirmed that the tensile strength, sealing strength, puncture strength, and elongation of the bioplastic films of Examples 15 to 17 increased compared to Example 7, and it was confirmed that physical properties can be changed depending on the composition ratio when other materials are mixed into the composition.

Claims

1. A bioplastic composition containing wheat bran, comprising a polyolefin resin, wheat bran, wax, inorganic filler, and surfactant.

2. In Paragraph 1, A bioplastic composition containing wheat bran, characterized in that the above-mentioned polyolefin resin is one or more selected from polyethylene (PE), polypropylene (PP), polybutylene, and polymethylpentene.

3. In Paragraph 1, A bioplastic composition containing wheat bran, characterized in that the above polyolefin resin is included in an amount of 40 to 70 weight% in the above composition.

4. In Paragraph 1, A bioplastic composition containing wheat bran, characterized in that the size of the wheat bran is 5 to 30 μm.

5. In Paragraph 4, A bioplastic composition characterized by the above-mentioned uniformity of wheat bran size (PDI) being 2 or less.

6. In Paragraph 1, A bioplastic composition containing wheat bran, characterized in that the wheat bran has a moisture content of 1 to 10% or less.

7. In Paragraph 1, A bioplastic composition containing wheat bran, characterized in that the wheat bran is included in an amount of 10 to 30 weight percent.

8. In Paragraph 1, The above wax is one or more selected from paraffin wax, liquid paraffin wax, beeswax, molda wax, candelilla wax, polyethylene wax, and polypropylene wax. A bioplastic composition containing wheat bran, characterized in that the above wax is included in an amount of 10 to 20 weight percent in the composition.

9. In Paragraph 1, The above inorganic filler is one or more selected from the group consisting of calcium carbonate, silica, mica, and talc, and A bioplastic composition containing wheat bran, characterized in that the above-mentioned inorganic filler is included in an amount of 5 to 20 weight percent within the composition.

10. In Paragraph 1, The above surfactant is characterized by being one or more selected from fatty acids such as stearic acid, myristic acid, palmitic acid, arachidic acid, oleic acid, linolenic acid, and hydrogenated fatty acids, and polyol series such as glycerin, butylene glycol, propylene glycol, dipropylene glycol, pentylene glycol, hexylene glycol, polyethylene glycol, and sorbitol. A bioplastic composition containing wheat bran, characterized by including 0.5 to 5 weight percent of the above surfactant.

11. In Paragraph 1, A bioplastic composition containing wheat bran, characterized by further including 10 to 30 parts by weight of a polyolefin resin per 100 parts by weight of the total composition after preparation of the composition.

12. Bioplastic pellets comprising the composition of claim 1.

13. A bioplastic film comprising the composition of claim 1.

14. In Paragraph 13, The above film is a bioplastic film characterized by further comprising a polyolefin resin.

15. A method for manufacturing pellets comprising a bioplastic composition including wheat bran, 1) a step of preparing a bioplastic composition containing wheat bran by heating and mixing a polyolefin resin, wheat bran, wax, inorganic filler, and a surfactant; and 2) Step of forming into pellets; A method for manufacturing bioplastic pellets including 16. In Paragraph 15, A method for manufacturing bioplastic pellets containing wheat bran, characterized in that the wheat bran undergoes a classification and pulverization process before administration and heating / mixing, after grinding, and after grinding.

17. In Paragraph 15, A method for manufacturing a bioplastic film containing wheat bran, characterized by additionally including a polyolefin resin in the bioplastic pellets manufactured by the above manufacturing method.

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