Biopolymer composition, its manufacturing method and bioplastics using the same

Abstract

This application relates to a biopolymer composition containing 83.5% by weight or more of a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); an antioxidant; and a lubricant, and having an elongation of 90% or more and 500% or less, a method for producing the same, and a bioplastic using the same.

Description

[Technical Field]

[0001] This specification claims the benefit of the filing date of Korean Patent Application Nos. 10-2019-0113590 and 10-2019-0113588, filed with the Korean Intellectual Property Office on September 16, 2019, the entire contents of which are incorporated herein by reference. The present invention relates to a biopolymer composition, a method for producing the same, and a bioplastic using the same. [Background technology]

[0002] Conventional plastics are considered to be the main culprits of environmental pollution because they do not decompose within a short period of time. Therefore, research into biodegradable, environmentally friendly biopolymers and bioplastics is being actively conducted.

[0003] Polylactic acid is known as a biopolymer that is biodegradable and has excellent mechanical properties such as tensile strength and elastic modulus. However, it has poor elongation properties and is prone to brittleness, which limits its usefulness as a general-purpose resin.

[0004] In the past, in order to compensate for the elongation characteristics of polylactic acid, two or more resins were mixed using solution polymerization (solution blending), but this had the disadvantage of being limited in terms of mass production and resulting in different physical properties.

[0005] Therefore, there is a demand for a method for producing a biopolymer composition that is advantageous for future mass production, allows stable evaluation of physical properties, and has improved elongation. Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention seeks to provide a biopolymer composition having high elongation properties.

[0007] The present invention seeks to provide biopolymer compositions with improved impact strength.

[0008] The present invention aims to provide a method for producing a biopolymer composition that can mass-produce a biopolymer composition having a high elongation rate and can provide stable evaluation of its physical properties. [Means for solving the problem]

[0009] The present invention provides a biopolymer composition comprising 83.5% by weight or more of a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); an antioxidant; and a lubricant, and having an elongation of 90% or more and 500% or less.

[0010] The present invention also provides a method for producing a biopolymer composition, comprising the steps of: preparing a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); mixing the copolymer resin with an antioxidant and a lubricant to form a mixture; and compounding the mixture in an extrusion process. [Effects of the Invention]

[0011] The biopolymer composition according to one embodiment of the present invention has excellent mechanical properties and a high elongation percentage.

[0012] The biopolymer composition according to one embodiment of the present invention has excellent mechanical properties and high impact strength.

[0013] The method for producing a biopolymer according to one embodiment of the present invention allows mass production of a biopolymer composition with high elongation, and enables stable evaluation of physical properties. DETAILED DESCRIPTION OF THE INVENTION

[0014] The present invention will now be described in more detail.

[0015] In this specification, when a part "comprises" a certain component, this does not mean that it can further include other components, unless otherwise specified.

[0016] As used herein, the term "polymerized" means that the compound to be polymerized is included as a comonomer. The copolymer resin produced by polymerizing the comonomer contains, as a repeating unit, the structure of the comonomer excluding the terminal linking group used in the polymerization.

[0017] In this specification, the elongation, tensile strength and tensile modulus indicate the mechanical properties of plastics, and will be explained in detail below.

[0018] Elongation, also known as breaking elongation, indicates the percentage of elongation of the plastic until it breaks, and is calculated using the following formula in units of %.

number

[0019] Tensile strength refers to the maximum stress when a plastic breaks under a tensile load, and is calculated using the following formula, expressed in units of MPa.

number

[0020] The tensile modulus of elasticity means the ratio of stress to deformation rate in a section where deformation changes linearly with stress, and is calculated by the following formula, and its unit is GPa.

number

[0021] In one embodiment of the present invention, the elongation, tensile strength, and tensile modulus of the biopolymer composition were measured according to ASTM D638, by pelletizing the biopolymer composition, processing it into dog-bone test specimens, and measuring them with a Universal Testing Machine (UTM) at a measurement speed of 10 mm / min.

[0022] Impact strength is the energy required to break a plastic material by an impact load divided by a unit area, and there are various impact strength measurement methods such as Izod, Charpy, falling weight (dart), and tensile impact strength. In this specification, the Izod impact strength measurement method was used.

[0023] In one embodiment of the present invention, the impact strength of a biopolymer composition was measured using an Izod impact strength test. A pelletized biopolymer composition was processed into impact strength test specimens using injection molding, and then the Izod impact was analyzed. Specifically, the Izod impact strength test uses a pendulum of a fixed weight. The impact strength is calculated by striking the test specimen with the pendulum and dividing the absorbed energy obtained from the height of the rotation by the cross-sectional area of ​​the notch in the test specimen. A plastic test specimen is placed vertically, and an impact is applied to the top of the specimen to measure the energy (force) consumed to break the specimen. Therefore, the Izod impact strength increases as the radius of the notch decreases.

[0024] In one embodiment of the present invention, polylactic acid (PLA) is a polymer of lactic acid, a thermoplastic aliphatic polyester extracted from renewable biomass, where biomass refers to plant or animal materials used as raw materials in industrial fields.

[0025] The polylactic acid is a type of biopolymer having biodegradability, and has a repeating unit of the following chemical formula 1, and the number of repeats (n) may be 1 to 5,000. [ka]

[0026] In one embodiment of the present invention, poly 3-hydroxypropionate (P(3HP)) is a polymer of 3-hydroxypropionate and a type of polyhydroxyalkanoate. The polyhydroxyalkanoate is a compound synthesized by a microorganism and is a biodegradable biopolymer.

[0027] The poly3-hydroxypropionate (P(3HP)) has a repeating unit of the following chemical formula 2 as a polyester, and the repeating number (n) may be 1 to 5,000. [ka]

[0028] In one embodiment of the present invention, the copolymer resin is obtained by polymerizing lactic acid (LA) and 3-hydroxypropionate (3HP) at a weight ratio of 1:99 to 99:1, preferably 5:95 to 95:5, and more preferably 10:90 to 90:10.

[0029] In one embodiment of the present invention, the copolymer resin is obtained by polymerizing lactic acid (LA) and 3-hydroxypropionate (3HP) in a ratio of 50:50 to 90:10, or 70:30 to 90:10.

[0030] In one embodiment of the present invention, the copolymer resin is a polymer of polylactic acid (PLA) and poly3-hydroxypropionate (P(3HP)).

[0031] In one embodiment of the present invention, the copolymer resin may be a random copolymer, a block copolymer, or an alternating copolymer.

[0032] In one embodiment of the present invention, the copolymer resin is a block copolymer resin of the lactic acid (LA) and the 3-hydroxypropionate (3HP).

[0033] In one embodiment of the present invention, the copolymer resin can be prepared by a conventional copolymer preparation method that can be directly prepared and used. For example, the copolymer resin can be prepared by solution polymerization.

[0034] In the present invention, lactic acid (LA) and 3-hydroxypropionate (3HP) are polymerized as a copolymer resin, and a single resin is used when included in a biopolymer composition. This eliminates the need to blend the two polymer resins, and therefore eliminates the need to use a dispersant. This provides a biopolymer composition that is advantageous in terms of production cost and manufacturing process, while also improving elongation.

[0035] A biopolymer composition according to one embodiment of the present invention comprises 83.5% by weight or more and less than 100% by weight of the copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP).

[0036] In one embodiment of the present specification, the biopolymer composition can contain the copolymer resin in an amount of 99% by weight or more but less than 100% by weight. A biopolymer composition containing 99% by weight or more of the copolymer resin has excellent biodegradability, thereby providing environmentally friendly products using the biopolymer composition.

[0037] In one embodiment of the present invention, the biopolymer composition may further contain 0.01 to 0.5 parts by weight, preferably 0.1 to 0.4 parts by weight, of an antioxidant relative to 100 parts by weight of the total biopolymer composition.

[0038] If the antioxidant is contained in an amount less than 0.01 parts by weight, there is a problem that oxidative decomposition occurs due to heat during the extrusion process, and if it is contained in an amount more than 0.5 parts by weight, there is a problem that the biodegradability of the biopolymer composition decreases.

[0039] In one embodiment of the present specification, the biopolymer composition may further contain 0.01 to 0.5 parts by weight, and preferably 0.1 to 0.3 parts by weight, of a lubricant relative to 100 parts by weight of the total biopolymer composition.

[0040] When the lubricant is contained within the above range, extrusion processing becomes easy and uniform physical properties can be obtained after extrusion. On the other hand, when the lubricant is contained in an amount of less than 0.01 parts by weight, extrusion processability decreases, and when the lubricant is contained in an amount of more than 0.5 parts by weight, the biodegradability of the biopolymer composition decreases.

[0041] The antioxidants include, but are not limited to, hindered phenol antioxidants, amine antioxidants, thio antioxidants, and phosphine antioxidants, which may be used alone or in combination. Specific examples include phosphoric acid-based heat stabilizers such as phosphoric acid, trimethyl phosphate, and triethyl phosphate; 2,6-di-t-butyl-p-cresol, octadecyl-3-(4-hydroxy-3,5-di-t-butylphenyl)propionate, tetrabis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, and 3,5-di-t-butyl-4-hydroxybenzyl phosphite. Sulfite diethyl ester, 2,2-thiobis(4-methyl-6-t-butylphenol), 2,6-g,t-butylphenol, 4,4'-butylidene-bis(3-methyl-6-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), bis[3,3-bis-(4'-hydroxy-3'-tert-butylphenyl)butanoic acid] glycol ester (Bis[3,3-bis-(4'-hydroxy-3'-tert-butylphenyl)butanoic acid]glycol hindered phenol primary antioxidants such as pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) (or 2,2-bis(((3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoyl)oxy)methyl)propane-1,3-diyl bis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate)); amine secondary antioxidants such as phenyl-α-naphthylamine, phenyl-β-naphthylamine, N,N'-diphenyl-p-phenylenediamine, or N,N'-di-β-naphthyl-p-phenylenediamine;Thio-based secondary antioxidants such as dilauryl disulfide, dilauryl thiopropionate, distearyl thiopropionate, mercaptobenzothiazole, or tetramethylthiuram disulfide tetrabis[methylene-3-(laurylthio)propionate]methane; or triphenyl phosphite, tris(nonylphenyl) phosphite, triisodecyl phosphite, bis(2,4-dibutylphenyl)pentaerythritol diphosphite phosphite-based secondary antioxidants such as tris-(2,4-di-tert-butylphenyl)phosphite, tris-(2,4-di-tert-butylphenyl)phosphite, or (1,1'-Biphenyl)-4,4'-Diylbisphosphonous acid tetrakis[2,4-bis(1,1-dimethylethyl)phenyl]ester;

[0042] In one embodiment of the present invention, the antioxidant may be a hindered phenol antioxidant.

[0043] The lubricant may be a mixture of any one external lubricant selected from the group consisting of low molecular weight polyethylene oxide, wax, polyethylene, stearic acid oxide, and stearic acid, and any one internal lubricant selected from the group consisting of aromatic alcohol, low fatty acid, and metal stearic acid, but is not limited thereto.

[0044] In one embodiment of the present invention, the lubricant includes a secondary antioxidant, preferably a phosphite-based secondary antioxidant.

[0045] In one embodiment of the present invention, the secondary antioxidant may be tris-(2,4-di-tert-butylphenyl)phosphite.

[0046] In one embodiment of the present invention, the elongation of the biopolymer composition is 90% or more and 500% or less, preferably 95% or more and 500% or less, more preferably 100% or more and 500% or less.

[0047] When existing compounding resins, such as PBAT (poly(butylene adipate terephthalate)) or PBS (poly(butylene succinate)), are used to increase the low elongation of polylactic acid, the elongation increases but the tensile properties become relatively low. In contrast, the biopolymer composition of the present invention can have a high elongation while maintaining tensile strength, making it usable as a material in the packaging field.

[0048] In one embodiment of the present invention, the tensile strength of the biopolymer composition may be 40 MPa to 70 MPa, or 50 MPa to 70 MPa, and the tensile modulus may be 2.5 GPa to 5 GPa, or 3 GPa to 5 GPa.

[0049] In one embodiment of the present invention, the impact strength of the biopolymer composition may be 60 J / m or more and 200 J / m or less.

[0050] In another embodiment, the biopolymer composition comprises 83.5% by weight or more and 94.5% by weight or less of the copolymer resin, an antioxidant, and a lubricant, and may further comprise a strength additive and a dispersant. When the strength additive and dispersant are included, the impact strength of the biopolymer composition may be 100 J / m or more and 200 J / m or less.

[0051] In one embodiment of the present invention, the biopolymer composition may comprise from 83.5 to 94.5 wt %, preferably from 87 to 94.5 wt %, more preferably from 87 to 90 wt %, of the copolymer resin.

[0052] The strength reinforcing agent may be, but is not limited to, a silicone-based strength reinforcing agent, an acrylic-based strength reinforcing agent, a butadiene-based strength reinforcing agent, or a silicone-acrylic strength reinforcing agent. A person skilled in the art to which the present invention pertains may select and use an appropriate strength reinforcing agent.

[0053] In one embodiment of the present invention, the reinforcing agent is a silicone-acrylic reinforcing agent, and the biopolymer composition containing the silicone-acrylic reinforcing agent has the advantage of being excellent in low-temperature impact strength and chemical impact resistance.

[0054] The dispersant may be a polymeric, nonionic, anionic, or cationic dispersant. Specific examples include, but are not limited to, one or more selected from the group consisting of polyalkylene glycols and esters thereof, polyoxyalkylene polyalcohols, ester alkylene oxide adducts, alcohol alkylene oxide adducts, sulfonate esters, sulfonate salts, carboxylate esters, carboxylate salts, alkylamide alkylene oxide adducts, and alkylamines.

[0055] In one embodiment of the present invention, the biopolymer composition may contain 5 to 15 parts by weight of a strength reinforcement agent and 0.5 to 1.5 parts by weight of a dispersant, relative to 100 parts by weight of the total biopolymer composition. The inclusion of the strength reinforcement agent and dispersant can provide a biopolymer composition with improved impact strength. If the strength reinforcement agent and dispersant are present in amounts less than the above ranges, the tensile properties of the biopolymer composition, i.e., elongation, tensile strength, and tensile modulus, may decrease. If the amounts are greater than the above ranges, the biopolymer composition may contain less biopolymer, resulting in a problem of reduced biodegradability.

[0056] In one embodiment of the present invention, the biopolymer composition comprising the strength enhancing agent and the dispersing agent may have a tensile strength of 40 MPa or more and 60 MPa or less, and a tensile modulus of elasticity of 2.5 GPa or more and 4.5 GPa or less.

[0057] In one embodiment of the present invention, the impact strength of the biopolymer composition containing the strength enhancing agent and the dispersant may be 100 J / m or more and 200 J / m or less, preferably 120 J / m or more and 200 J / m or less. The impact strength is measured using an Izod impact strength measurement method, in which the biopolymer composition prepared in pellet form is processed into an impact strength test piece using injection molding, and then the Izod impact is analyzed.

[0058] In one embodiment of the present invention, the biopolymer composition is prepared by an extrusion process. Biopolymer compositions prepared by an extrusion process have a higher elongation than biopolymer compositions prepared by a solution blending process.

[0059] In another embodiment, the biopolymer composition comprising the strength enhancing agent and dispersing agent is produced by an extrusion process and can provide superior impact strength to biopolymer compositions produced by solution blending.

[0060] In one embodiment of the present invention, there is provided a method for producing the aforementioned biopolymer composition, comprising the steps of: providing a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); mixing the copolymer resin with an antioxidant and a lubricant to form a mixture; and compounding the mixture in an extrusion process.

[0061] The method for producing a biopolymer composition according to one embodiment of the present invention may further comprise the step of adding a strength enhancing agent and a dispersing agent to the mixture prior to the compounding step in the extrusion process.

[0062] In one embodiment of the present invention, the compounding step in the extrusion process uses an extruder, and the extruder may be a water-cooled twin-screw extruder.

[0063] In one embodiment of the present invention, the extrusion screw speed of the water-cooled twin-screw extruder is 100 rpm to 200 rpm, preferably 100 rpm to 150 rpm, and more preferably 100 rpm to 120 rpm.

[0064] In one embodiment of the present invention, the pelletizer speed of the water-cooled twin-screw extruder is 100 rpm to 500 rpm, preferably 200 rpm to 500 rpm, and more preferably 300 rpm to 400 rpm.

[0065] In one embodiment of the present invention, the extruder may be a co-rotating twin screw extruder, and the screw speed and pelletizer speed in the extruder may be adjusted to facilitate compounding.

[0066] In one embodiment of the present invention, the temperature of the final discharge portion of the screw of the water-cooled twin-screw extruder is 170°C to 250°C, preferably 190°C to 250°C, and more preferably 200°C to 230°C. The final discharge portion of the screw may refer to a portion corresponding to 1 / 20 of the total length of the screw. If the temperature at the final discharge portion is too low, the resin may not be discharged smoothly, and if the temperature is too high, the physical properties of the polymer may deteriorate and discoloration may occur.

[0067] In one embodiment of the present invention, the temperature of the remaining screw portion excluding the final discharge portion of the water-cooled twin-screw extruder is 160°C to 220°C, preferably 180°C to 220°C, and more preferably 180°C to 200°C.

[0068] In one embodiment of the present invention, the temperature of the main hopper of the water-cooled twin-screw extruder is 130°C to 200°C, preferably 150°C to 200°C, and more preferably 150°C to 170°C.

[0069] In one embodiment of the present invention, a bioplastic is provided that comprises the biopolymer composition described above.

[0070] In one embodiment of the present specification, the method for producing a bioplastic using the biopolymer composition is not particularly limited as long as it is a method used in the technical field.

[0071] The bioplastics can be used for, but are not limited to, packaging materials, films, fibers, medical devices, or containers. [Example]

[0072] The present invention will be described in more detail with reference to the following examples, which are merely for illustrative purposes and are not intended to limit the scope of the present invention.

[0073] [Experimental Example 1] Preparation of biopolymer composition Example 1 99.5 wt% of copolymer resin (PLH, weight ratio of PLA to P(3HP): 90:10), 0.3 wt% of antioxidant (Irganox 1010), and 0.2 wt% of lubricant (Irgafos 168, containing a secondary antioxidant) were added to a water-cooled twin-screw extruder, and then compounded and pelletized under the following conditions: extrusion screw speed (100 rpm), pelletizer speed (400 rpm), temperature of the final screw discharge section (210°C), temperature of the remaining screw section (190°C), and temperature of the main hopper (160°C).

[0074] <Example 2> The same procedure as in Example 1 was repeated, except that 88 wt% of copolymer resin (PLH), 10 wt% of strength enhancer (Biostrength-150), and 1.5 wt% of dispersant (BYK-P-401) were added instead of 99.5 wt% of copolymer resin (PLH).

[0075] <Comparative Example 1> 100% by weight of copolymer resin (PLH, weight ratio of PLA and P(3HP): 90:10) was added to a water-cooled twin-screw extruder, and then compounded and pelletized under the following conditions: extrusion screw speed (100 rpm), pelletizer speed (400 rpm), temperature of the final screw discharge part (210°C), temperature of the remaining screw parts (190°C), and temperature of the main hopper (160°C).

[0076] <Comparative Example 2> 89.5 wt% of polylactic acid (PLA), 10 wt% of poly3-hydroxypropionate (P(3HP)), 0.3 wt% of antioxidant (Irganox1010), and 0.2 wt% of lubricant (Irgafos168) were mixed in chloroform and then dried at room temperature.

[0077] <Comparative Example 3> The same procedure as in Example 1 was repeated, except that 89.5 wt% of polylactic acid (PLA) and 10 wt% of poly(butylene adipate terephthalate) (PBAT) were added instead of 99.5 wt% of copolymer resin (PLH).

[0078] <Comparative Example 4> The same procedure as in Example 1 was repeated, except that 79.2 wt% of polylactic acid (PLA) and 8.8 wt% of poly(butylene adipate terephthalate) (PBAT) were added instead of 99.5 wt% of copolymer resin (PLH), 10 wt% of strength reinforcing agent, and 1.5 wt% of dispersing agent.

[0079] <Comparative Example 5> The same procedure as in Example 1 was repeated, except that 89.5 wt% of polylactic acid (PLA) and 10 wt% of poly(butylene succinate) (PBS) were added instead of 99.5 wt% of copolymer resin (PLH).

[0080] <Comparative Example 6> The same procedure as in Example 1 was repeated, except that 79.2 wt% of polylactic acid (PLA) and 8.8 wt% of poly(butylene succinate) (PBS) were added instead of 99.5 wt% of copolymer resin (PLH), 10 wt% of strength reinforcing agent, and 1.5 wt% of dispersing agent.

[0081] [Experimental Example 2] Measurement of mechanical properties of biopolymer composition Examples 1 and 2 and Comparative Examples 1 to 6 were processed into dog-bone test specimens using a compression method, and then the elongation, tensile strength, and tensile modulus were measured using a UTM (Universal Testing Machine) (measurement speed: 10 mm / min).

[0082] Furthermore, the pelletized Examples 1 and 2 and Comparative Examples 1 to 6 were processed into impact strength test pieces using injection molding, and Izod impact was analyzed.

[0083] The results of the measurements are shown in Table 1 below, where the parts by weight of the biopolymer are based on the total weight of the biopolymer composition.

[0084] [Table 1]

[0085] From the results in Table 1, it can be seen that the biopolymer composition of Example 1 according to the present invention has similar levels of tensile strength and tensile modulus to those of Comparative Examples 2, 3, and 5, which do not contain the copolymer resin (PLH) of the present invention, and also has elongations of approximately 1.7 times, 32 times, and 29 times.

[0086] In addition, Example 1, which was extrusion compounded using an antioxidant and a lubricant according to the present invention, had higher tensile strength and tensile modulus than Comparative Example 1, which was extrusion compounded without an antioxidant or a lubricant. This indicates that an antioxidant and a lubricant must be included in the composition as essential components for compounding using an extrusion process.

[0087] Comparative Example 2 was compounded by a solution blending process rather than extrusion compounding, and compared to Example 1 according to the present invention, it had lower tensile strength, tensile modulus, and impact strength, and was particularly inferior in terms of elongation.

[0088] In the case of Example 2, in which a strength enhancer and a dispersant were further added, the impact strength was twice that of Example 1. When compared with Comparative Examples 4 and 6, which do not contain the copolymer resin (PLH) of the present invention, it can be seen that Comparative Examples 4 and 6 contain a strength enhancer and a dispersant, but their impact strength is more than twice that of Example 2.

Claims

1. 83.5% by weight or more of a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); a hindered phenolic primary antioxidant; and Lubricants containing phosphite-based secondary antioxidants Including, The elongation measured in accordance with ASTM D638 is 90% or more and 500% or less, The copolymer resin has a repeating unit of lactic acid represented by the following chemical formula 1 and a repeating unit of 3-hydroxypropionate represented by the following chemical formula 2: A biopolymer composition, wherein the copolymer resin is a block copolymer of lactic acid and 3-hydroxypropionate (3HP) polymerized in a weight ratio of 70:30 to 90:10: 【Chemical 1】 【Chemistry 2】 In Chemical Formulas 1 and 2, n is a repeating number ranging from 1 to 5,000.

2. 2. The biopolymer composition of claim 1, comprising at least 99% by weight of the copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP).

3. 2. The biopolymer composition of claim 1, wherein the copolymer resin is obtained by polymerizing lactic acid (LA) and 3-hydroxypropionate (3HP) in a weight ratio of 1:99 to 99:

1.

4. 2. The biopolymer composition of claim 1, wherein the copolymer resin is a polymer of polylactic acid (PLA) and poly3-hydroxypropionate (P(3HP)).

5. 2. The biopolymer composition of claim 1, wherein the copolymer resin is a block copolymer of the lactic acid (LA) and the 3-hydroxypropionate (3HP).

6. The biopolymer composition of claim 1, wherein the primary antioxidant and the lubricant are each present in an amount of 0.01 to 0.5 parts by weight per 100 parts by weight of the total biopolymer composition.

7. The biopolymer composition comprises: The tensile strength measured in accordance with ASTM D638 is 40 MPa or more and 70 MPa or less, 10. The biopolymer composition of claim 1, having a tensile modulus, measured according to ASTM D638, of 2.5 GPa or greater and 5 GPa or less.

8. The biopolymer composition comprises: The copolymer resin is contained in an amount of 83.5% by weight or more and 94.5% by weight or less, a strength enhancing agent; and a dispersant, 2. The biopolymer composition of claim 1, having an impact strength of 100 J / m or more and 200 J / m or less, measured according to an Izod impact strength measurement method.

9. 9. The biopolymer composition of claim 8, wherein the strength enhancing agent is selected from silicone-based, acrylic-based, butadiene-based, and silicone-acrylic-based strength enhancing agents.

10. The biopolymer composition of claim 8, wherein the strength enhancing agent is contained in an amount of 5% to 15% by weight and the dispersing agent is contained in an amount of 0.5% to 1.5% by weight, based on 100% by weight of the total biopolymer composition.

11. The biopolymer composition comprises: The tensile strength measured in accordance with ASTM D638 is 40 MPa or more and 60 MPa or less, 9. The biopolymer composition of claim 8, having a tensile modulus measured according to ASTM D638 of 2.5 GPa or greater and 4.5 GPa or less.

12. Providing a copolymer resin of lactic acid (LA) and 3-hydroxypropionate (3HP); mixing the copolymer resin with a primary antioxidant and a lubricant to form a mixture; compounding the mixture in an extrusion process; A method for producing the biopolymer composition of any one of claims 1 to 11, comprising:

13. 13. The method of claim 12, further comprising adding a strength enhancing agent and a dispersing agent to the mixture prior to compounding in the extrusion process.

14. A bioplastic comprising the biopolymer composition of any one of claims 1 to 11.

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