Biodegradable resin composition, biodegradable resin molded article, and method for producing the same

Abstract

(A) A polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound, wherein the (A) polyolefin-based compound is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and the (C) aliphatic-aromatic copolyester-based compound and the (D) modified polyolefin-based compound are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D), to provide a biodegradable resin composition and a biodegradable resin molded article.

Description

Technical Field

[0001] According to one embodiment, the present invention relates to a biodegradable resin composition, a biodegradable resin molded article, and a method for producing the same. Specifically, according to one embodiment, the present invention relates to a biodegradable resin composition, a biodegradable resin molded article, and a method for producing the same, which impart biodegradability to polyolefin, which is hardly decomposable, provide excellent biodegradability, significantly improve the drop impact strength, and also improve the mechanical properties.

Background Art

[0002] Plastics have excellent physical properties, are inexpensive and lightweight. Therefore, plastics have exceeded the limitations of natural materials, and various polymer substances centered on plastics have been developed, building modern scientific civilization. Plastics are strong, lightweight, durable, and not easily decomposed. Due to such properties, plastics are widely used from industrial materials to disposable materials.

[0003] However, environmental pollution caused by plastic waste, which is becoming increasingly serious day by day, has become a problem. For example, due to the detection of highly toxic dioxin, the detection of environmental hormones, the shortage of landfills for waste plastics, etc., the social demand for environmentally friendly plastics is increasing. In addition, the legal regulatory standards for the use of non-degradable plastics are gradually being strengthened. As a result, the development of biodegradable polymers has emerged as a very important matter.

[0004] According to the standards of ASTM (American Society for Testing and Materials) in the United States, degradable plastics refer to plastics whose chemical structure changes significantly under specific environmental conditions for a certain period of time, and the change in their properties can be measured by standard test methods, and can be roughly divided into photodegradable plastics, biodegradable plastics, and biodegradable plastics.

[0005] Specifically, photo-degradable plastics refer to plastics that are decomposed by light in the form of photo-oxidation or ketone photo-degradation. Since photo-degradable plastics are decomposed by light, they have the disadvantage that they are not decomposed when buried underground where light is blocked.

[0006] Bio-disintegrating plastics are partially degradable plastics manufactured by adding a certain amount of biodegradable substances such as starch to non-degradable general-purpose resins (such as polyethylene and polypropylene). In the case of South Korea, in order to avoid confusion with biodegradable plastics, the term "bio-disintegrating plastics" is used to distinguish them separately.

[0007] Biodegradable plastics refer to plastics that can be completely decomposed into water and carbon dioxide, or water and methane gas by microorganisms existing in nature such as bacteria, algae, and fungi.

[0008] Previously, photo-degradable plastics or bio-disintegrating plastics were mainly used, but in recent years, the development of biodegradable plastics has attracted attention as an important matter. From the perspective of raw materials, it can be distinguished from existing petroleum-based plastics by using natural plant resources.

[0009] For example, Patent Document 1 discloses a thermoplastic film composition containing a polymer blend of immiscible polymer components. This composition contains a plasticized natural polymer, a polyolefin, a biodegradable polymer, and a compatibilizer in the same polymer molecule. The plasticized natural component and the biodegradable polymer component form a multiphase, and the petroleum-based polyolefin forms a minor phase. Also, this composition can be manufactured into a film containing a renewable natural polymer component.

[0010] However, the development of a biodegradable resin composition that simultaneously satisfies more improved biodegradability and mechanical properties, particularly impact strength, is required.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0012] According to one embodiment, a biodegradable resin composition and a biodegradable resin molded article are provided, which provide excellent biodegradability even when including a polyolefin-based compound having poor degradability and have a significantly improved drop impact strength.

[0013] According to another embodiment, a biodegradable resin composition and a biodegradable resin molded article having excellent mechanical properties are provided.

MEANS FOR SOLVING THE PROBLEMS

[0014] According to one embodiment, a biodegradable resin composition is provided.

[0015] 1. The biodegradable resin composition includes (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound. (A) The polyolefin-based compound is contained in an amount of 7% to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% to 80% by weight in the total of (A) to (D).

[0016] 2. In 1, (A) the polyolefin-based compound may be contained in an amount of 9% to 20% by weight in the total of (A) to (D).

[0017] 3. In 1 to 2, (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound may be contained in a total amount of 55% to 80% by weight in the total of (A) to (D).

[0018] In 4.1 to 3, in the mixture, the aliphatic-aromatic copolymer polyester compound and the modified polyolefin compound may be contained in a weight ratio of the aliphatic-aromatic copolymer polyester compound: the modified polyolefin compound of 5:1 to 15:1.

[0019] In 5.1 to 4, in the total of (A) to (D), (A) may be contained in an amount of 7% by weight to 30% by weight, (B) may be contained in an amount of 20% by weight to 35% by weight, (C) may be contained in an amount of 35% by weight to 70% by weight, and (D) may be contained in an amount of 1% by weight to 10% by weight.

[0020] In 6.1 to 5, the polyolefin compound may include one or more selected from the group consisting of ultra-low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, and combinations thereof.

[0021] In 7.1 to 6, the polyolefin compound has a melt index (MI) of 0.1 g / 10 min to 50 g / 10 min, measured at 190 °C under a load of 2.16 kg according to ASTM D1238, a density of 0.900 g / cm 3 to 0.930 g / cm 3 and a weight average molecular weight of 50,000 g / mol to 1,000,000 g / mol.

[0022] In 8.1 to 7, the biodegradable resin may include one or more selected from the group consisting of thermoplastic starch, poly(lactic acid), polycaprolactone, poly(butylene succinate), poly(glycolic acid), polyhydroxyalkanoate, cellulose, chitin, and mixtures thereof.

[0023] In 9.8, the thermoplastic starch may have an average particle size (D50) of 100 nm to 600 nm.

[0024] In 10.1 to 9, the thermoplastic starch may further contain a plasticizer.

[0025] 11.1~10, the aliphatic-aromatic copolymer polyester compound can include one or more selected from the group consisting of poly(butylene adipate / terephthalate) and poly(butylene succinate / terephthalate).

[0026] 12.1~11, the modified polyolefin compound can include one or more selected from the group consisting of polyethylene grafted with maleic anhydride and polypropylene grafted with maleic anhydride.

[0027] 13.1~12, in the biodegradable resin composition, the total of (A)~(D) can be contained at 95% by weight or more.

[0028] 14.1~13, the biodegradable resin composition can have a biodegradability of 60% or more compared to the biodegradability of cellulose based on the measurement according to the ISO 14855-1 standard on a 45-day basis.

[0029] 15. According to one embodiment, the biodegradable resin molded article is manufactured by molding the biodegradable resin composition.

[0030] 16.15, the biodegradable resin molded article can have an impact strength of 190 g to 1000 g based on the measurement according to ASTM D1790.

[0031] According to one embodiment, (1) a polyolefin-based compound (A), a biodegradable resin (B), an aliphatic-aromatic copolyester-based compound (C), and a modified polyolefin-based compound (D) are mixed and melt-blended so that the polyolefin-based compound (A) is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and the aliphatic-aromatic copolyester-based compound (C) and the modified polyolefin-based compound (D) are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D) to obtain a biodegradable resin composition, and (2) the biodegradable resin composition is molded. A method for producing a biodegradable resin molded article including these steps is provided.

Effects of the Invention

[0032] According to one embodiment, it is possible to provide a biodegradable resin composition and a biodegradable resin molded article that provide excellent biodegradability even when including a polyolefin-based compound that is difficult to decompose and have a significantly improved drop impact strength.

[0033] According to another embodiment, it is possible to provide a biodegradable resin composition and a biodegradable resin molded article having excellent mechanical properties.

Brief Description of the Drawings

[0034]

Figure 1

Modes for Carrying Out the Invention

[0035] Hereinafter, the present invention will be described in more detail. However, the present invention can be embodied in various different forms and is not limited to the embodiments described herein.

[0036] In this specification, when a certain part "includes" a certain component, this means that, unless otherwise stated to the contrary, it does not exclude other components but may further include other components.

[0037] In this specification, unless otherwise specified, singular expressions are interpreted to mean not only singular but also plural in the context.

[0038] In this specification, when describing a numerical range, "X to Y" means X or more and Y or less (X ≤ and ≤ Y).

[0039] In this specification, "biodegradable" means that a substance can be easily decomposed into water, carbon dioxide and / or methane by microorganisms such as bacteria, algae, and fungi. Therefore, a biodegradable resin composition may mean that not only physical disintegration of a molded article produced therefrom occurs, but also a decrease in molecular weight due to main chain scission of the polymer as its constituent component occurs.

[0040] According to one embodiment, it is possible to provide a biodegradable resin composition and a biodegradable resin molded article that provide excellent biodegradability even when including a hardly decomposable polyolefin-based compound. Further, it is possible to provide a biodegradable resin composition and a biodegradable resin molded article with significantly improved drop impact strength. Further, it is possible to provide a biodegradable resin composition and a biodegradable resin molded article having excellent mechanical properties.

[0041] [Biodegradable Resin Composition] According to one embodiment, the biodegradable resin composition includes (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound, wherein (A) the polyolefin-based compound is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D).

[0042] [(A) Polyolefin-Based Compound] Polyolefin-based compounds can be widely used because they are inexpensive and have excellent processability. However, polyolefin-based compounds are recognized as a major cause of environmental pollution due to their recalcitrance and substantial lack of biodegradability on their own.

[0043] Here, "substantially non-biodegradable on its own" means that a substance without additives for imparting biodegradability (e.g., polyolefin-based compound alone) is not significantly biodegraded into carbon dioxide and / or methane (specifically, biodegraded) within a limited period (e.g., 1 year, 2 years, 3 years, 4 years, or 5 years) under various treatment conditions such as sunlight, sea, or landfill.

[0044] When a polyolefin-based compound is mixed with each of the components described below, the biodegradability of the composition containing the polyolefin-based compound can be improved.

[0045] According to one embodiment, the polyolefin-based compound can be a homopolymer in which an olefinic monomer is homopolymerized, or a copolymer in which an olefinic comonomer or a polar comonomer is copolymerized with an olefinic monomer.

[0046] According to one embodiment, the olefinic monomer can be any of ethylene, propylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, 1-octene, 1-decene, 1-undecene, 1-dodecene, 1-tetradecene, or 1-hexadecene, but is not limited thereto. The comonomer and / or the polar comonomer can be vinyl acetate or the like, but is not limited thereto.

[0047] According to one embodiment, the polyolefin-based compound can include polyethylene, polyethylene-based copolymer, polypropylene, polypropylene-based copolymer, or a mixture thereof.

[0048] Preferably, the polyolefin-based compound is polyethylene. Polyethylene can facilitate the realization of all the effects of the present application described above.

[0049] Specifically, the polyethylene can include one or more selected from the group consisting of very-low-density polyethylene (VLDPE), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), and combinations thereof.

[0050] More preferably, the polyolefin-based compound can be low-density polyethylene, linear low-density polyethylene, or a mixture thereof. When low-density polyethylene, linear low-density polyethylene, or a mixture thereof is used in a composition containing the components described below, it can facilitate the production of a biodegradable resin composition having excellent tensile strength, tear strength, elongation rate, or drop impact strength, etc.

[0051] According to one embodiment, the polyolefin-based compound can have a melt index (MI) of 0.1 g / 10 min to 50 g / 10 min as measured according to ASTM D1238 at 190 °C under a load of 2.16 kg, and a density of 0.900 g / cm 3 ~0.930 g / cm 3It can have a density. The polyolefin-based compound can have a weight average molecular weight of 50,000 g / mol to 1,000,000 g / mol, preferably 50,000 g / mol to 300,000 g / mol. When the polyolefin-based compound satisfies the melt index, density, and weight average molecular weight, it can facilitate the production of a biodegradable resin composition having excellent tensile strength, tear strength, elongation rate, or impact strength upon falling, etc. The "weight average molecular weight" can be measured as a polystyrene equivalent value by gel permeation chromatography. This is a method already known to those skilled in the art.

[0052] The polyolefin-based compound is contained at 7% by weight to 30% by weight in the total of (A) to (D).

[0053] If the content of the polyolefin-based compound in the total of (A) to (D) is less than 7% by weight, it may become impossible to produce and process a film from the composition, and the impact strength upon falling of the finally produced film or molded article may be extremely low and it may become impossible to use it as a molded article. If the content of the polyolefin-based compound in the total of (A) to (D) exceeds 30% by weight, the effect of improving the impact strength upon falling of the film or molded article produced from the composition may become weak, and the biodegradability of the composition may also become low. For example, the content of the polyolefin-based compound in the total of (A) to (D) can be 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30% by weight.

[0054] According to one embodiment, the polyolefin-based compound can be contained at 9% by weight to 20% by weight in the total of (A) to (D). Within this range, the increase in the impact strength upon falling due to the increase in the content of the polyolefin-based compound is significant, and the other physical properties of the film or molded article can also be excellent.

[0055] According to one embodiment, the polyolefin-based compound may be contained in an amount of 9% by weight to 17% by weight in the total of (A) to (D). Within the above range, the increase in the drop impact strength due to the increase in the content of the polyolefin-based compound is remarkable, and other physical properties of the film or molded article can be excellent.

[0056] According to one embodiment, the polyolefin-based compound may be contained in an amount of 9% by weight to 15% by weight in the total of (A) to (D). Within the above range, the increase in the drop impact strength due to the increase in the content of the polyolefin-based compound is remarkable, and other physical properties of the film or molded article can be excellent.

[0057] According to one embodiment, the polyolefin-based compound may be contained in an amount of 10% by weight to 15% by weight in the total of (A) to (D). Within the above range, the increase in the drop impact strength due to the increase in the content of the polyolefin-based compound is remarkable, and other physical properties of the film or molded article can be remarkably excellent.

[0058] [(B) Biodegradable resin] The biodegradable resin can be included in a composition containing a polyethylene-based compound that is hardly decomposable to improve biodegradability.

[0059] According to one embodiment, the biodegradable resin can include one or more selected from the group consisting of thermoplastic starch (TPS), poly(lactic acid) (PLA), polycaprolactone (PCL), poly(butylene succinate) (PBS), poly(glycolic acid) (PGA), polyhydroxyalkanoate (PHA), cellulose, chitin, and mixtures thereof, but is not particularly limited thereto.

[0060] According to one embodiment, the biodegradable resin is thermoplastic starch.

[0061] Thermoplastic starch is starch that is excellent in biodegradability and consists of two components, amylose and amylopectin. Since the glucose of amylose has a hydroxy group, thermoplastic starch exhibits hydrophilicity, and by having hydrogen bonds, the biodegradability of the composition can be enhanced. According to one embodiment, thermoplastic starch is a granular dry powder, and the average particle size (D50) is 100 nm to 600 nm, preferably 500 nm to 600 nm. Within this range, the effects of the present application can be easily exhibited in the composition. The "average particle size (D50)" can mean the particle size corresponding to 50% in volume percentage when arranged from the minimum value to the maximum value by a particle size analyzer, and can be measured by a conventional method known to those skilled in the art.

[0062] Thermoplastic starch can be derived from plants. For example, thermoplastic starch can include at least one selected from the group consisting of rice starch, wheat starch, corn starch, sweet potato starch, potato starch, tapioca starch, cassava starch, and modified starches thereof, but is not particularly limited thereto. Here, modified starch can mean alpha-starch obtained by physically or chemically treating starch, acid-treated starch, oxidized starch, cationic starch, ester-modified starch, ether-modified starch, etc.

[0063] Polylactic acid, polycaprolactone, poly(butylene succinate), and polyglycolic acid can correspond to aliphatic polyester-based compounds. These are excellent in biodegradability by microorganisms and can provide biocompatibility and the like. In particular, polyglycolic acid is excellent in mechanical properties such as high strength and high heat resistance, and thus is widely used especially for medical applications.

[0064] Polyhydroxyalkanoate corresponds to a polyester and can exhibit excellent biodegradability and degradability under all conditions such as aerobic, anaerobic, and composting conditions. In particular, polyhydroxybutyrate (PHB), which is a type of polyhydroxyalkanoate, is a single polymer in which D-3-hydroxy-butyric acid is linearly linked. This can provide biological functions such as starch or glycogen as an energy storage synthesized intracellularly by a very diverse range of bacteria.

[0065] Cellulose and chitin are a type of natural polymer, are excellent in biodegradability, are easily available, and can be used as environmentally friendly materials because of their non-toxicity.

[0066] The biodegradable resin can be composed of the above-mentioned thermoplastic starch, polylactic acid, polycaprolactone, polybutylene succinate, polyglycolic acid, polyhydroxyalkanoate, cellulose, chitin, and mixtures thereof alone, but may further contain a plasticizer.

[0067] According to one embodiment, the thermoplastic starch can further contain a plasticizer. When the thermoplastic starch contains a plasticizer, the plasticizer can control the binding force between starches, thereby reducing the crystallinity of the starch itself and improving the compatibility with a different resin. In addition, the plasticizer can eliminate the carbonization phenomenon of starch that may occur during extrusion processing, and enable the effect to appear even if the particle size of the thermoplastic starch is smaller than at the initial stage.

[0068] The plasticizer is not particularly limited as long as it can plasticize starch. For example, the plasticizer can be glycerin, polyethylene glycol, sorbitol, polyhydric alcohol, a hydrogen bond-forming organic compound having no hydroxyl group, an anhydride of sugar alcohol, animal protein, plant protein, aliphatic acid, phthalate ester, dimethyl, and diethyl succinate, and esters related thereto, glycerol triacetate, glycerol monoacetate, glycerol diacetate, glycerol monopropionate, glycerol dipropionate, glycerol tripropionate, glycerol butanoate, glycerol stearate, esters of lactic acid, esters of citric acid, esters of adipic acid, esters of stearic acid, esters of oleic acid, esters of other aliphatic or aromatic acids, or combinations thereof. Preferably, the plasticizer can be glycerin.

[0069] According to one embodiment, the plasticizer can be contained in a biodegradable resin, such as thermoplastic starch, in an amount of 10% to 40% by weight, for example, 20% to 40% by weight. Within this range, the effect of adding the plasticizer can be obtained, and the effect of adding the biodegradable resin can be prevented from being impaired.

[0070] According to one embodiment, the biodegradable resin can be contained in an amount of 20% to 35% by weight in the total of (A) to (D). Within this range, the composition can provide excellent biodegradability. In addition, the composition can easily exhibit excellent tensile strength, tear strength, elongation rate, and / or impact strength upon falling, etc. For example, the biodegradable resin can be contained in the total of (A) to (D) in an amount of 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35% by weight. Preferably, the biodegradable resin can be contained in the total of (A) to (D) in an amount of 20% to 32% by weight, 20% to 30% by weight, 23% to 30% by weight, 23% to 28% by weight.

[0071] [(C) aliphatic-aromatic copolymer polyester-based compound, and (D) modified polyolefin-based compound] According to one embodiment, the composition includes a mixture of an aliphatic-aromatic copolyester compound and a modified polyolefin compound. The mixture is used as a compatibilizer in the composition, and when the polyolefin compound described above is included at 7% to 30% by weight, the impact strength of a specimen or molded article formed of the composition can be significantly improved. In the present application, among several compatibilizers, a mixture of an aliphatic-aromatic copolyester compound and a modified polyolefin compound is used as the compatibilizer. By including the mixture in the composition at 45% to 80% by weight and the polyolefin compound at 7% to 30% by weight, one feature can be that the impact strength is significantly improved while providing biodegradability.

[0072] The mixture is included at 45% to 80% by weight in the total of (A) to (D). If the mixture is less than 45% by weight in the total of (A) to (D), the effect of improving compatibility by adding the mixture becomes weak, and biodegradability may also deteriorate. If the mixture exceeds 80% by weight in the total of (A) to (D), the effect of improving compatibility is not so significant compared to the increase in the content of the mixture, and the improvement in impact strength may also become weak. For example, the mixture may be included at 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80% by weight in the total of (A) to (D).

[0073] According to one embodiment, the mixture may be included at 55% to 80% by weight in the total of (A) to (D). Within this range, the improvement of the effects of the present application described above may be facilitated, and the production of molded articles may be facilitated.

[0074] According to one embodiment, the mixture may be included at 55% to 70% by weight in the total of (A) to (D). Within this range, the improvement of the effects of the present application described above may be facilitated, and the production of molded articles may be facilitated.

[0075] According to one embodiment, the mixture may be contained in an amount of 60% to 70% by weight based on the total of (A) to (D). Within this range, the effects of the present application described above can be easily improved, and the production of molded articles can be facilitated.

[0076] According to one embodiment, in the mixture, the aliphatic-aromatic copolyester compound and the modified polyolefin compound may be contained in a weight ratio of aliphatic-aromatic copolyester compound:modified polyolefin compound of 5:1 to 15:1, for example, 7:1 to 15:1, 8:1 to 15:1. Within this range, it can be excellent in impact strength, compatibility, and biodegradability effect. For example, the weight ratio can be 5:1, 5.5:1, 6:1, 6.5:1, 7:1, 7.5:1, 8:1, 8.5:1, 9:1, 9.5:1, 10:1, 10.5:1, 11:1, 11.5:1, 12:1, 12.5:1, 13:1, 13.5:1, 14:1, 14.5:1, 15:1. Preferably, it may be contained in a weight ratio of 10:1 to 15:1. Within this range, it can be significantly excellent in impact strength, compatibility, and biodegradability effects.

[0077] [(C) Aliphatic-aromatic copolyester compound] The aliphatic-aromatic copolyester compound can be a component that imparts biodegradability, and at the same time can be applied as a compatibilizer.

[0078] Since polyolefin compounds are chemically non-polar, their compatibility with polar biodegradable resins, especially thermoplastic starch, can be poor. Therefore, by further introducing an aliphatic-aromatic copolyester compound, the compatibility between the respective components in the composition can be improved, and biodegradability can be imparted to the polyolefin compound.

[0079] According to one embodiment, the aliphatic-aromatic copolyester compound can include one or more selected from the group consisting of poly(butylene adipate / terephthalate) (PBAT) and poly(butylene succinate / terephthalate) (PBST), but is not particularly limited thereto.

[0080] According to one embodiment, the aliphatic-aromatic copolyester compound can be poly(butylene adipate / terephthalate).

[0081] According to one embodiment, the aliphatic-aromatic copolyester compound can have a weight average molecular weight of 10,000 g / mol to 100,000 g / mol, preferably 20,000 g / mol to 50,000 g / mol as measured by gel permeation chromatography. Within the above range, it can be easier to provide a biodegradable resin composition having excellent tensile strength, tear strength, elongation rate, or drop impact strength, etc. for specimens such as films and molded articles formed from the composition.

[0082] According to one embodiment, the aliphatic-aromatic copolyester compound can be contained in an amount of 35% by weight to 70% by weight based on the total of (A) to (D). Within the above range, the biodegradable resin composition can easily provide excellent biodegradability and excellent tensile strength, tear strength, elongation rate, or drop impact strength, etc. For example, the aliphatic-aromatic copolyester compound can be contained in an amount of 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70% by weight. Preferably, the aliphatic-aromatic copolyester compound can be contained in an amount of 40% by weight to 70% by weight, 45% by weight to 70% by weight, 50% by weight to 70% by weight, 55% by weight to 70% by weight, or 55% by weight to 65% by weight based on the total of (A) to (D).

[0083] [(D) Modified polyolefin compound] The modified polyolefin compound can act as a compatibilizer in the biodegradable resin composition.

[0084] According to one embodiment, the modified polyolefin compound can be a maleic anhydride-grafted polyolefin-based compound. Here, the polyolefin in the modified olefin-based compound may be the same or different from the above polyolefin-based compound. Preferably, the modified polyolefin compound can include one or more selected from the group consisting of maleic anhydride-grafted polyethylene (A-g-PE) and maleic anhydride-grafted polypropylene (A-g-PP). More preferably, the modified polyolefin compound may be maleic anhydride-grafted polyethylene.

[0085] The maleic anhydride-grafted polyolefin can improve the compatibility between the chemically non-polar polyolefin-based compound and the polar biodegradable resin, and at the same time improve the interfacial adhesion between the polyolefin-based compound and the biodegradable resin. When the interfacial adhesion between different resins is excellent, the decomposition of the biodegradable resin under composting conditions induces the oxidation of the polyolefin-based compound in contact with it, and as a result, the degradability of the hardly degradable polyolefin-based compound can be imparted.

[0086] According to one embodiment, the content of maleic anhydride in the maleic anhydride-grafted polyolefin can be 1.0 wt% to 2.5 wt%. When the grafting rate of maleic anhydride is 1.0 wt% to 2.5 wt%, the effect of improving the adhesive force to the polar substrate can be exerted.

[0087] According to one embodiment, the modified polyolefin-based compound may be contained in an amount of 1% to 10% by weight in the total of (A) to (D). Within the above range, the biodegradable resin composition can easily provide excellent biodegradability as well as excellent tensile strength, tear strength, elongation rate, or impact strength. For example, the modified polyolefin-based compound may be contained in the total of (A) to (D) at 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10% by weight. Preferably, the modified polyolefin-based compound may be 3% to 8% by weight, 3% to 7% by weight, 4% to 7% by weight, or 4% to 6% by weight in the total of (A) to (D).

[0088] In the biodegradable resin composition, the total of (A) to (D) may be 95% by weight or more, for example, 95% to 100% by weight, 95% by weight, 96% by weight, 97% by weight, 98% by weight, 99% by weight, 100% by weight.

[0089] In addition to (A) to (D), the biodegradable resin composition may further contain ordinary additives known to those skilled in the art.

[0090] According to one embodiment, when measured by differential scanning calorimetry (DSC) or dynamic mechanical analysis (DMA), the melting temperature of the biodegradable resin composition may be 100°C to 130°C.

[0091] According to one embodiment, when measured according to ASTM D1238 at 190°C under a load of 2.16 kg, the melt index of the biodegradable resin composition may be 0.01 g / 10 min to 10 g / 10 min. In the embodiments of the present invention, the melt index of the biodegradable resin composition may be 0.1 g / 10 min to 8 g / 10 min, 0.1 g / 10 min to 5 g / 10 min, 0.1 g / 10 min to 3 g / 10 min, 0.1 g / 10 min to 2 g / 10 min, 0.1 g / 10 min to 1.5 g / 10 min.

[0092] According to one embodiment, when measured according to the ISO 14855-1 standard, the biodegradability of the biodegradable resin composition can be 60% or more compared to the biodegradability of cellulose on a 45-day basis. In a preferred embodiment of the present invention, when measured according to the ISO 14855-1 standard, the biodegradability of the biodegradable resin composition can be 65% or more, 70% or more, 72% or more, 75% or more, 77% or more, 80% or more, 85% or more, or 90% or more compared to the biodegradability of cellulose on a 45-day basis.

[0093] When measuring the biodegradability of the resin composition according to another embodiment of the present invention according to the ISO 14855-1 standard, on a 45-day basis for determining whether it is a biodegradable resin in a short-term measurement, the biodegradability of the resin composition is 60% or more compared to the biodegradability of cellulose, and by showing a tendency of continuous increase in biodegradability, it can be expected to meet the requirement of 90% or more biodegradability on a 180-day basis, which is a requirement for biodegradable resins.

[0094] According to one embodiment, the biodegradable resin composition can be produced by a production method of a biodegradable resin composition including a step of mixing and melt-blending (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound so that (A) the polyolefin-based compound is contained in an amount of 7% to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% to 80% by weight in the total of (A) to (D).

[0095] Here, the specific details regarding (A) the polyolefin-based compound, (B) the biodegradable resin, (C) the aliphatic-aromatic copolyester-based compound, and (D) the modified polyolefin-based compound are substantially the same as those described in the above item of the biodegradable resin composition, so they are omitted.

[0096] Moreover, when the respective contents of (A) a polyolefin compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester compound, and (D) a modified polyolefin compound satisfy the above ranges, a biodegradable resin composition having excellent biodegradability and excellent tensile strength, tear strength, elongation rate, or impact strength can be produced.

[0097] In a preferred embodiment, polyethylene, thermoplastic starch, poly(butylene adipate / terephthalate), and polyethylene grafted with maleic anhydride can be melt-blended.

[0098] The melt blending can be carried out using at least one selected from a single-screw extruder, a twin-screw extruder, a kneader, a Brabender Plasti-Corder, a mixing roll, and a mixer, but is not particularly limited thereto. In a preferred embodiment, the melt blending can be carried out using a twin-screw extruder.

[0099] According to one embodiment, the melt blending can be carried out at a temperature of 100°C to 300°C. In a preferred embodiment of the present invention, the melt blending can be carried out at a temperature of 160°C to 210°C.

[0100] In the case of melt blending using a twin-screw extruder, the rotational speed of the extruder screw can be 40 rpm to 700 rpm, preferably 100 rpm to 200 rpm.

[0101] According to one embodiment, the biodegradable resin composition produced by melt blending the above components can have a pellet form, but is not particularly limited thereto.

[0102] According to one embodiment, a method for imparting biodegradability to a polyolefin-based compound, the method comprising: (1) providing a polyolefin-based compound that is not biodegradable by itself; (2) providing a biodegradable resin, an aliphatic-aromatic copolyester-based compound, and a modified polyolefin-based compound; and (3) melt-blending the polyolefin-based compound, the biodegradable resin, the aliphatic-aromatic copolyester-based compound, and the modified polyolefin-based compound to obtain a resin composition. When measuring the biodegradation degrees of the resin composition obtained in step (3) and cellulose according to the ISO 14855-1 standard, the biodegradation degree of the resin composition can be 60% or more compared to that of cellulose based on a 45-day standard.

[0103] According to one embodiment, when measured according to the ISO 14855-1 standard, the biodegradation degree of the biodegradable resin composition based on a 45-day standard can be 65% or more, 70% or more, 72% or more, 75% or more, 77% or more, 80% or more, 85% or more, or 90% or more compared to the biodegradation degree of cellulose.

[0104] Here, the specific contents regarding the polyolefin-based compound, the biodegradable resin, the aliphatic-aromatic copolyester-based compound, and the modified polyolefin-based compound are the same as those described in the above item of the biodegradable resin composition, and these melt-blending methods are the same as those described in the above item of the manufacturing method of the biodegradable resin composition.

[0105] [Biodegradable Resin Molded Article] According to one embodiment, a biodegradable resin molded article can be manufactured by molding the biodegradable resin composition according to the above-described one embodiment.

[0106] The method for molding the biodegradable resin composition is not particularly limited, and molding methods known in the technical field to which the present invention pertains can be used. For example, the biodegradable resin composition can be molded by ordinary methods such as blown film molding, extrusion molding, injection molding, casting molding, etc. to manufacture a biodegradable resin molded article.

[0107] In an embodiment of the present invention, the biodegradable resin molded article can include, but is not particularly limited to, any one of a film, a sheet, a bag, a sack, a bottle, a cap, a lid, a box, a dish, and a cup. In a preferred embodiment of the present invention, the biodegradable resin molded article can be a film, a sheet, a bag, or a sack.

[0108] In an embodiment of the present invention, when measured according to the ISO 14855-1 standard, the biodegradability of the biodegradable resin molded article can be 60% or more compared to the biodegradability of cellulose on a 45-day basis. In a preferred embodiment of the present invention, when measured according to the ISO 14855-1 standard, the biodegradability of the biodegradable resin molded article can be 65% or more, 70% or more, 72% or more, 75% or more, 77% or more, 80% or more, 85% or more, or 90% or more compared to the biodegradability of cellulose on a 45-day basis.

[0109] When measuring the biodegradability of a resin molded article according to another embodiment of the present invention according to the ISO 14855-1 standard, it can be predicted that the biodegradability of the resin molded article is 60% or more compared to the biodegradability of cellulose on a 45-day basis for determining whether it is a biodegradable resin in a short-term measurement, while satisfying the requirement of a biodegradability of 90% or more.

[0110] According to one embodiment, when the biodegradable resin molded article is measured at 190 °C and a load of 2.16 kg according to ASTM D1238, the melt index can be 0.01 g / 10 min to 10 g / 10 min. In an embodiment of the present invention, the melt index of the biodegradable resin molded article can be 0.1 g / 10 min to 8 g / 10 min, 0.1 g / 10 min to 5 g / 10 min, 0.1 g / 10 min to 3 g / 10 min, 0.1 g / 10 min to 2 g / 10 min, 0.1 g / 10 min to 1.5 g / 10 min.

[0111] According to one embodiment, the biodegradable resin molded article can have a melt index ratio (MFR) of 20 to 100 between the melt index measured at 190°C under a load of 21.6 kg and the melt index measured at 190°C under a load of 2.16 kg in accordance with ASTM D1238. In an embodiment of the present invention, the MFR of the biodegradable resin molded article can be 20 to 80, 20 to 70, 30 to 100, 30 to 80, or 30 to 70.

[0112] According to one embodiment, the biodegradable resin molded article is a film having a thickness of 20 μm to 50 μm, preferably about 30 μm, and this film has a tensile strength in the machine direction (MD) of 100 kgf / cm 2 ~300 kgf / cm 2 and a tensile strength in the transverse direction (TD) of 100 kgf / cm 2 ~450 kgf / cm 2 According to one embodiment, the film can have a tensile strength in the machine direction of 100 kgf / cm 2 ~250 kgf / cm 2 and a tensile strength in the transverse direction of 100 kgf / cm 2 ~350 kgf / cm 2

[0113] According to one embodiment, the biodegradable resin molded article is a film having a thickness of 20 μm to 50 μm, preferably about 30 μm, and this film can have a machine direction Elmendorf tear strength of 200 g to 600 g and a transverse direction Elmendorf tear strength of 200 g to 1,000 g. In a preferred embodiment of the present invention, the film can have a machine direction Elmendorf tear strength of 200 g to 500 g and a transverse direction Elmendorf tear strength of 200 g to 800 g.

[0114] According to one embodiment, the biodegradable resin molded article is a film having a thickness of 20 μm to 50 μm, preferably about 30 μm, and this film can have an elongation rate in the machine direction of 200% to 600% and an elongation rate in the width direction of 200% to 800%. In a preferred embodiment of the present invention, the film can have an elongation rate in the machine direction of 200% to 500% and an elongation rate in the width direction of 300% to 700%.

[0115] According to one embodiment, the biodegradable resin molded article is a film having a thickness of 20 μm to 50 μm, preferably about 30 μm, and this film can have a drop impact strength of 190 g to 1,000 g. In a preferred embodiment of the present invention, the film can have a drop impact strength of 300 g to 800 g, 600 g to 800 g.

[0116] According to one embodiment, the biodegradable resin molded article is a film having a thickness of 20 μm to 50 μm, preferably about 30 μm, and this film has a tensile strength in the machine direction of 100 kgf / cm 2 ~300 kgf / cm 2 and a tensile strength in the width direction of 100 kgf / cm 2 ~450 kgf / cm 2 a Elmendorf tear strength in the machine direction of 200 g to 600 g, and a Elmendorf tear strength in the width direction of 200 g to 1,000 g, an elongation rate in the machine direction of 200% to 600%, and an elongation rate in the width direction of 200% to 800%, and a drop impact strength of 190 g to 1,000 g.

[0117] According to one embodiment, there is provided a method for manufacturing a biodegradable resin molded article, including the steps of obtaining the biodegradable resin composition and molding the biodegradable resin composition.

[0118] According to one embodiment, a method for manufacturing a biodegradable resin molded article includes: (1) a step of mixing and melt-blending a polyolefin-based compound (A), a biodegradable resin (B), an aliphatic-aromatic copolyester-based compound (C), and a modified polyolefin-based compound (D) so that (A) the polyolefin-based compound is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D) to obtain a biodegradable resin composition; and (2) a step of molding the biodegradable resin composition.

[0119] In the above step (1), the specific details regarding the polyolefin-based compound, the biodegradable resin, the aliphatic-aromatic copolyester-based compound, and the modified polyolefin-based compound are as described in the item of the method for manufacturing the above biodegradable resin composition, and these melt-blending methods are as described in the item of the method for manufacturing the above biodegradable resin composition.

[0120] In the above step (2), the method of molding the biodegradable resin composition is as described in the item of the above biodegradable molded article.

[0121] According to one embodiment, a method for imparting biodegradability to a polyolefin molded article that is not biodegradable by itself includes: (1) a step of providing a polyolefin-based compound that is not biodegradable by itself; (2) a step of providing a biodegradable resin, an aliphatic-aromatic copolyester-based compound, and a modified polyolefin-based compound; (3) a step of melt-blending the polyolefin-based compound, the biodegradable resin, the aliphatic-aromatic copolyester-based compound, and the modified polyolefin-based compound to obtain a resin composition; and (4) a step of molding the resin composition to obtain a resin molded article. When the biodegradability of the resin molded article obtained in step (4) and that of cellulose are measured according to the ISO 14855-1 standard, the biodegradability of the resin molded article is 60% or more compared to that of cellulose based on a 45-day standard.

[0122] In an embodiment of the present invention, when measured according to the ISO 14855-1 standard, the biodegradability of the biodegradable resin molded article can be 65% or more, 70% or more, 72% or more, 75% or more, 77% or more, 80% or more, 85% or more, or 90% or more compared to the biodegradability of cellulose on a 45-day basis.

[0123] Here, the specific details regarding the polyolefin-based compound, biodegradable resin, aliphatic-aromatic copolyester-based compound, and modified polyolefin-based compound are as described in the above item on the biodegradable resin composition, and these melt blending methods are as described in the above item on the manufacturing method of the biodegradable resin composition, and the method of molding the resin composition is as described in the above item on the biodegradable molded article.

[0124] [Examples] Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited only to these.

[0125] The components used in the following examples and comparative examples are as follows.

[0126] A1: LLDPE (linear low-density polyethylene, MI: 20 g / 10 min, density: 0.924 g / cm 3 , weight average molecular weight: 61000 g / mol)

[0127] A2: LPDE (low-density polyethylene, MI: 0.8 g / 10 min, density: 0.923 g / cm 3 )

[0128] B1: TPS (thermoplastic starch, Hanfa TPS, containing 25% by weight of plasticizer, average particle size (D50) of thermoplastic starch: 500 nm to 600 nm)

[0129] C1: PBAT (GIOSOLTEC SOLPOL-1000N, weight average molecular weight: 21,000 g / mol)

[0130] D1: MA-g-PE (DuPont, Fusabond(R) E588, polyethylene grafted with maleic anhydride)

[0131] [Production Example] The following components were mixed at the contents (unit: parts by weight) shown in Table 1 below to produce a biodegradable resin composition, and the produced composition was melt-blended at a temperature of 160°C to 210°C using a twin-screw extruder and pelletized. The obtained pellets were supplied to an extruder, heated at a mixing zone temperature of 190°C, and extruded to process a blown film. The blown film processing conditions were as follows: the screw was 40 mmφ, the die was 75 mmφ, the die gap was 2 mm, and the screw rotation speed was 180 rpm. The thickness of the finally produced film was about 30 μm.

[0132] [Test Example] The resin compositions obtained in each example and comparative example, and the film specimens formed therefrom were tested by the following methods. The results are shown in Table 1 and Figure 1 below.

[0133] (1) Melt index (MI) (unit: g / 10 min) and melt flow ratio (MFR) For the produced film, the melt index was measured at 190°C under a load of 2.16 kg according to ASTM D1238.

[0134] For the produced film, the melt index was measured at 190°C under a load of 2.16 kg and at 190°C under a load of 21.6 kg respectively according to ASTM D1238, and the ratio (MI 21.6 / MI 2.16 ) was determined.

[0135] (2) Absolute biodegradability (unit: %) and relative biodegradability (unit: %) To confirm the biodegradability of the resin composition based on 45 days and its subsequent trend, the biodegradability was measured for 48 days according to ISO 14855-1. The biodegradability of the resin composition was measured after pulverizing the pellets produced as described above to an average particle size (D50) of about 250 μm. The biodegradability of the molded product was measured after pulverizing the film produced as described above to an average particle size (D50) of about 250 μm. The biodegradability of cellulose was measured in the same manner as a reference example 1. The biodegradability measured above is described in Table 1 as the absolute biodegradability, and the absolute biodegradability in Table 1 is the biodegradability of the resin composition. The percentage of the biodegradability of the resin composition with respect to the biodegradability of cellulose was calculated as the relative biodegradability.

[0136] (3) Tensile strength (unit: kgf / cm 2 ) and elongation rate (unit: %) For the film produced as described above, it was measured in both the MD (machine direction) and TD (transverse direction) of the film according to ASTM D882.

[0137] (4) Elmendorf tear strength (unit: g) For the film produced as described above, it was measured in both the MD and TD of the film according to ASTM D1004.

[0138] (5) Drop impact strength (unit: g) For the film produced as described above, it was measured according to ASTM D1709.

[0139]

Table 1

[0140] As shown in Table 1 above, Specific Examples 1 to 7 of one embodiment provided excellent biodegradability even when including a hardly decomposable polyolefin-based compound, and it was confirmed that the drop impact strength was significantly improved, and mechanical properties such as tensile strength, elongation at break, and Elmendorf tear strength were also improved.

[0141] On the other hand, Comparative Examples that did not satisfy the configuration of one embodiment could not exhibit all of the above-described effects of the present application. In particular, even when including the aliphatic-aromatic copolyester-based compound and the modified polyolefin-based compound of the present application, Comparative Examples 1 and 4 in which the content of the polyolefin-based compound was outside the scope of the present application had extremely low drop impact strength, so that it could be difficult to use even when formed into a molded article.

[0142] As shown in FIG. 1, it was confirmed that Specific Examples 1, 2, 6 to 7 of one embodiment had significantly higher biodegradability compared to cellulose (Reference Example 1).

[0143] Simple modifications or changes of the present invention can be easily implemented by those having ordinary knowledge in the art, and all such modifications and changes can be regarded as being included in the scope of the present invention.

[0144] [Appendix] [Appendix 1] A biodegradable resin composition comprising (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound, wherein (A) the polyolefin-based compound is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D).

[0145] [Appendix 2] The biodegradable resin composition according to Appendix 1, wherein (A) the polyolefin-based compound is contained in an amount of 9% by weight to 20% by weight in the total of (A) to (D).

[0146] [Appendix 3] (C) The aliphatic-aromatic copolymer polyester compound and (D) the modified polyolefin compound are contained in a total of 55% by weight to 80% by weight in the total of (A) to (D), and the biodegradable resin composition according to Appendix 1.

[0147] [Appendix 4] In the mixture, the aliphatic-aromatic copolymer polyester compound and the modified polyolefin compound are contained in a weight ratio of the aliphatic-aromatic copolymer polyester compound: the modified polyolefin compound of 5:1 to 15:1, and the biodegradable resin composition according to Appendix 1.

[0148] [Appendix 5] In the total of (A) to (D), (A) is contained in 7% by weight to 30% by weight, (B) is contained in 20% by weight to 35% by weight, (C) is contained in 35% by weight to 70% by weight, and (D) is contained in 1% by weight to 10% by weight, and the biodegradable resin composition according to Appendix 1.

[0149] [Appendix 6] The polyolefin compound contains one or more selected from the group consisting of ultra-low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, and combinations thereof, and the biodegradable resin composition according to Appendix 1.

[0150] [Appendix 7] The polyolefin compound has a melt index (MI) of 0.1 g / 10 min to 50 g / 10 min, a density of 0.900 g / cm3 to 0.930 g / cm3, and a weight average molecular weight of 50,000 g / mol to 1,000,000 g / mol, measured according to ASTM D1238 at 190 °C under a load of 2.16 kg, and measured according to ASTM D1505, and the biodegradable resin composition according to Appendix 1.

[0151] [Appendix 8] The biodegradable resin composition according to Appendix 1 contains one or more selected from the group consisting of thermoplastic starch, poly(lactic acid), polycaprolactone, poly(butylene succinate), poly(glycolic acid), polyhydroxyalkanoate, cellulose, chitin, and mixtures thereof.

[0152] [Appendix 9] The biodegradable resin composition according to Appendix 8, wherein the thermoplastic starch has an average particle size (D50) of 100 nm to 600 nm.

[0153] [Appendix 10] The biodegradable resin composition according to Appendix 8, wherein the thermoplastic starch further contains a plasticizer.

[0154] [Appendix 11] The biodegradable resin composition according to Appendix 1, wherein the aliphatic-aromatic copolyester compound contains one or more selected from the group consisting of poly(butylene adipate / terephthalate) and poly(butylene succinate / terephthalate).

[0155] [Appendix 12] The biodegradable resin composition according to Appendix 1, wherein the modified polyolefin compound contains one or more selected from the group consisting of polyethylene grafted with maleic anhydride and polypropylene grafted with maleic anhydride.

[0156] [Appendix 13] The biodegradable resin composition according to Appendix 1, wherein the total of (A) to (D) in the biodegradable resin composition is contained at 95% by weight or more.

[0157] [Appendix 14] The biodegradable resin composition according to Appendix 1, wherein the biodegradability is 60% or more compared to the biodegradability of cellulose when measured according to the ISO 14855-1 standard on a 45-day basis.

[0158] [Appendix 15] A biodegradable resin molded article manufactured by molding the biodegradable resin composition according to any one of Appendices 1 to 14.

[0159] [Appendix 16] The biodegradable resin molded article has an impact strength of 190 g to 1000 g as measured by ASTM D1790, and is the biodegradable resin molded article according to Appendix 15.

[0160] [Appendix 17] (1) A step of mixing and melt-blending (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound so that (A) the polyolefin-based compound is contained in an amount of 7% to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% to 80% by weight in the total of (A) to (D) to obtain a biodegradable resin composition; (2) A step of molding the biodegradable resin composition; A method for manufacturing a biodegradable resin molded article, comprising:

Claims

1. A biodegradable resin composition comprising (A) a polyolefin-based compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester-based compound, and (D) a modified polyolefin-based compound, wherein (A) the polyolefin-based compound is contained in an amount of 7% to 30% by weight based on the total of (A) to (D), and (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 45% to 80% by weight based on the total of (A) to (D).

2. The biodegradable resin composition according to claim 1, wherein (A) the polyolefin-based compound is contained in an amount of 9% to 20% by weight based on the total of (A) to (D).

3. The biodegradable resin composition according to claim 1, wherein (C) the aliphatic-aromatic copolyester-based compound and (D) the modified polyolefin-based compound are contained in a total amount of 55% to 80% by weight based on the total of (A) to (D).

4. In the mixture, the aliphatic-aromatic copolyester-based compound and the modified polyolefin-based compound are contained in a weight ratio of the aliphatic-aromatic copolyester-based compound: the modified polyolefin-based compound of 5:1 to 15:

1. The biodegradable resin composition according to claim 1.

5. In the total of (A) to (D), (A) is contained in an amount of 7% to 30% by weight, (B) is contained in an amount of 20% to 35% by weight, (C) is contained in an amount of 35% to 70% by weight, and (D) is contained in an amount of 1% to 10% by weight. The biodegradable resin composition according to claim 1.

6. The polyolefin-based compound according to claim 1, comprising at least one selected from the group consisting of ultra-low density polyethylene, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, and combinations thereof.

7. The polyolefin-based compound has a melt index (MI) of 0.1 g / 10 min to 50 g / 10 min as measured according to ASTM D1238 at 190°C under a load of 2.16 kg, a density of 0.900 g / cm ３ to 0.930 g / cm ３ and a weight average molecular weight of 50,000 g / mol to 1,000,000 g / mol, and the biodegradable resin composition according to claim 1.

8. The biodegradable resin according to claim 1, comprising at least one selected from the group consisting of thermoplastic starch, poly(lactic acid), polycaprolactone, poly(butylene succinate), poly(glycolic acid), polyhydroxyalkanoate, cellulose, chitin, and mixtures thereof.

9. The biodegradable resin composition according to claim 8, wherein the thermoplastic starch has an average particle size (D50) of 100 nm to 600 nm.

10. The biodegradable resin composition according to claim 8, wherein the thermoplastic starch further contains a plasticizer.

11. The biodegradable resin composition according to claim 1, wherein the aliphatic-aromatic copolyester compound contains one or more selected from the group consisting of poly(butylene adipate / terephthalate) and poly(butylene succinate / terephthalate).

12. The biodegradable resin composition according to claim 1, wherein the modified polyolefin compound contains one or more selected from the group consisting of polyethylene grafted with maleic anhydride and polypropylene grafted with maleic anhydride.

13. The biodegradable resin composition according to claim 1, wherein the total of (A) to (D) is contained in an amount of 95% by weight or more in the biodegradable resin composition.

14. The biodegradable resin composition according to claim 1, wherein the biodegradability is 60% or more compared to the biodegradability of cellulose when measured according to the ISO 14855-1 standard on a 45-day basis.

15. A biodegradable resin molded article produced by molding the biodegradable resin composition according to any one of claims 1 to 14.

16. The biodegradable resin molded article according to claim 15, having a drop impact strength of 190 g to 1000 g as measured by ASTM D1790.

17. (1) A step of mixing and melt-blending (A) a polyolefin compound, (B) a biodegradable resin, (C) an aliphatic-aromatic copolyester compound, and (D) a modified polyolefin compound so that (A) the polyolefin compound is contained in an amount of 7% by weight to 30% by weight in the total of (A) to (D), and (C) the aliphatic-aromatic copolyester compound and (D) the modified polyolefin compound are contained in a total amount of 45% by weight to 80% by weight in the total of (A) to (D) to obtain a biodegradable resin composition; (2) A step of molding the biodegradable resin composition; A method for producing a biodegradable resin molded article, comprising the above steps.

Images