Biodegradable resin composition and biodegradable nonwoven fabric

Abstract

The invention relates to a biodegradable resin composition and a biodegradable non-woven fabric. The present invention provides a biodegradable resin composition comprising: a first biodegradable resin comprising a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid; and a crystallization promoter, in which the crystallization promoter is included in a content of 100 ppm to 50,000 ppm, and the isothermal crystallization time at 90 DEG C according to measurement method 1 in the specification is 10 seconds to 900 seconds.

Description

Technical Field

[0001] The present invention relates to a biodegradable resin composition and a biodegradable molded article including the same. Background Art

[0002] Polyethylene, polypropylene, and polyethylene terephthalate have been used as materials for clothing fibers, nonwoven fabrics, etc. In recent years, concerns about environmental problems have been increasing day by day, and thus solutions are needed to solve the problems of waste of short-lived clothing fibers and disposable nonwoven fabrics.

[0003] To solve these problems, research on biodegradable resins is currently being actively carried out. Polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), and polybutylene succinate (PBS) have been introduced as biodegradable resins.

[0004] However, compared with other materials, the spinning ability of biodegradable resins is poor, and thus they are limited in the manufacture of fibers or nonwoven fabrics.

[0005] In addition, in order to improve the spinning ability of biodegradable resins, various biodegradable resins are combined, but the miscibility between biodegradable resins with different properties is reduced, resulting in problems such as fiber-to-fiber fusion or fiber breakage after spinning. Summary of the Invention

[0006] Technical Problem

[0007] Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a biodegradable resin composition having excellent biodegradability, improved spinning ability, injection moldability, and foaming property, and excellent mechanical properties, and a biodegradable molded article including the biodegradable resin composition.

[0008] Another object of the present invention is to provide a biodegradable resin composition having a soft texture and excellent elasticity and being environmentally friendly, and a biodegradable nonwoven fabric including the biodegradable resin composition.

[0009] Technical Solution

[0010] According to one aspect of the present invention, the above and other objects can be achieved by providing a biodegradable resin composition comprising: a first biodegradable resin including a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid; and a crystallization promoter, wherein the crystallization promoter is included in an amount of 100 ppm to 50,000 ppm and has an isothermal crystallization time of 10 seconds to 900 seconds at 90 °C according to Measurement Method 1 below:

[0011] [Measurement Method 1]

[0012] 1) Heat the biodegradable resin composition to 220 °C at a heating rate of 10 °C / min and then hold for 5 minutes;

[0013] 2) Then, cool the biodegradable resin composition to 90 °C at a cooling rate of 100 °C / min and hold in an isothermal state for 100 minutes;

[0014] 3) Using differential scanning calorimetry, measure the time when the total area of the crystallization peak of the biodegradable resin composition is halved.

[0015] In an embodiment of the present invention, the biodegradable resin composition may further include at least one second biodegradable resin selected from the group consisting of: polybutylene succinate, polylactic acid, polybutylene adipate, polybutylene succinate adipate, polybutylene terephthalate succinate, polyhydroxybutyrate-valerate, polycaprolactone, polybutylene adipate-co-butylene terephthalate succinate, and polybutylene adipate terephthalate succinate.

[0016] In an embodiment of the present invention, the crystallization promoter may include at least one of an organic nucleating agent and an inorganic nucleating agent.

[0017] In an embodiment of the present invention, the biodegradable resin composition may include an organic nucleating agent in an amount of 10 ppm to 5,000 ppm.

[0018] In an embodiment of the present invention, the biodegradable resin composition may include an inorganic nucleating agent in an amount of 100 ppm to 10,000 ppm.

[0019] In an embodiment of the present invention, the inorganic nucleating agent may include at least one of rutile phase titanium dioxide and anatase phase titanium dioxide.

[0020] In an embodiment of the present invention, the inorganic nucleating agent may have an average diameter (D 50 ) of 0.1 μm to 0.5 μm.

[0021] In an embodiment of the present invention, the biodegradable resin composition may further include an external lubricant.

[0022] In an embodiment of the present invention, the biodegradable resin composition may include an external lubricant in an amount of 100 ppm to 5,000 ppm.

[0023] In an embodiment of the present invention, the biodegradable resin composition may have a crystallization temperature (Tc) of 35°C to 90°C as measured by differential scanning calorimetry.

[0024] In an embodiment of the present invention, the biodegradable resin composition may have a melt flow rate of 2 g / 10 min to 60 g / 10 min as measured under the conditions of 190°C and 2.16 kg.

[0025] In an embodiment of the present invention, according to Measurement Method 2 below, the biodegradable resin composition may have a tensile strength of 25 MPa or higher:

[0026] [Measurement Method 2]

[0027] 1) Prepare a specimen with a thickness of 300 μm from the biodegradable resin composition;

[0028] 2) For the specimen, measure the tensile strength using a universal testing machine at a rate of 100 mm / min.

[0029] In an embodiment of the present invention, the elongation at break of the specimen measured using a universal testing machine may be 800% to 1,200%.

[0030] In an embodiment of the present invention, the isothermal crystallization time may be 40 seconds to 800 seconds.

[0031] According to another aspect of the present invention, there is provided a biodegradable molded article including a biodegradable resin composition, the biodegradable resin composition including a first biodegradable resin, the first biodegradable resin including a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid, and a crystallization promoter, wherein based on the total weight of the biodegradable resin composition, the crystallization promoter is included in an amount of 100 ppm to 50,000 ppm, and the isothermal crystallization time at 90°C according to Measurement Method 1 below is 10 seconds to 900 seconds:

[0032] [Measurement Method 1]

[0033] 1) Heat the biodegradable resin composition at a heating rate of 10 °C / min to 220 °C, and then hold for 5 minutes;

[0034] 2) Then, cool the biodegradable resin composition at a cooling rate of 100 °C / min to 90 °C, and maintain the isothermal state for 100 minutes;

[0035] 3) Use differential scanning calorimetry to measure the time when the total area of the crystallization peak of the biodegradable resin composition is halved.

[0036] In an embodiment of the present invention, the biodegradable molded article can be a nonwoven fabric, an injection molded article, or a foam molded article.

[0037] According to another aspect of the present invention, there is provided a biodegradable nonwoven fabric comprising: a biodegradable resin composition, the biodegradable resin composition comprising a first biodegradable resin, the first biodegradable resin comprising a diol, an aromatic dicarboxylic acid, and an aliphatic dicarboxylic acid, wherein the biodegradable resin composition has a first irreversible strain rate of less than 30% measured by the following measuring method 3:

[0038] [Measuring method 3]

[0039] 1) While the biodegradable resin composition is placed between a pair of flat stainless steel molds, compress it at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm;

[0040] 2) Cut the biodegradable resin composition sheet to produce a sample, the sample comprising a test part having a width of 3.18 mm and a length of 25 mm;

[0041] 3) Pull the test part in the longitudinal direction at a speed of 10 mm / min at room temperature, where the test part is pulled 40% more than its total length;

[0042] 4) In a state without external force, let the test part recover at room temperature for 5 minutes;

[0043] 5) The first irreversible strain rate is obtained from the following equation 1:

[0044] [Equation 1]

[0045] First irreversible strain rate = (Length of the recovered test segment - 25 mm) / 25 mm.

[0046] In an embodiment of the present invention, the biodegradable resin composition may have a second irreversible strain rate of less than 20% measured by the following measuring method 4:

[0047] [Measuring method 4]

[0048] 1) With the biodegradable resin composition placed between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm;

[0049] 2) The biodegradable resin composition sheet is cut to produce a sample, the sample including a test piece having a width of 3.18 mm and a length of 25 mm;

[0050] 3) The test piece is pulled in the longitudinal direction at a speed of 10 mm / min at room temperature, where the test piece is pulled 30% more than its total length;

[0051] 4) In a state without external force, the test piece is allowed to recover at room temperature for 5 minutes;

[0052] 5) The second irreversible strain rate is obtained from the following equation 2:

[0053] [Equation 2]

[0054] Second irreversible strain rate = (length of the recovered test segment - 25 mm) / 25 mm.

[0055] In an embodiment of the present invention, the biodegradable resin composition may have a third irreversible strain rate of less than 10% measured by the following measuring method 5:

[0056] [Measuring method 5]

[0057] 1) With the biodegradable resin composition placed between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm;

[0058] 2) The biodegradable resin composition sheet is cut to produce a sample, the sample including a test piece having a width of 3.18 mm and a length of 25 mm;

[0059] 3) The test piece is pulled in the longitudinal direction at a speed of 10 mm / min at room temperature, where the test piece is pulled 20% more than its total length;

[0060] 4) Without external force, restore the test part at room temperature for 5 minutes;

[0061] 5) The third irreversible strain rate is obtained from the following Equation 3:

[0062] [Equation 3]

[0063] Third irreversible strain rate = (Length of the restored test segment - 25 mm) / 25 mm.

[0064] In an embodiment of the present invention, the biodegradable resin composition may have a fourth irreversible strain rate of less than 5% measured by the following Measuring Method 6:

[0065] [Measuring Method 6]

[0066] 1) While placing the biodegradable resin composition between a pair of flat stainless steel molds, compress it at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm;

[0067] 2) Cut the biodegradable resin composition sheet to produce a sample, the sample including a test part having a width of 3.18 mm and a length of 25 mm;

[0068] 3) Pull the test part at a speed of 10 mm / min in the longitudinal direction at room temperature, where the test part is pulled 10% more than its total length;

[0069] 4) Without external force, restore the test part at room temperature for 5 minutes;

[0070] 5) The fourth irreversible strain rate is obtained from the following Equation 4:

[0071] [Equation 4]

[0072] Fourth irreversible strain rate = (Length of the restored test segment - 25 mm) / 25 mm.

[0073] According to an embodiment of the present invention, the biodegradable resin composition may further include a second biodegradable resin, wherein the second biodegradable resin includes one or more selected from the group consisting of: polybutylene succinate, polylactic acid, polybutylene adipate, polybutylene adipate-co-succinate, polybutylene terephthalate succinate, polyhydroxybutyrate-valerate, polycaprolactone, and polybutylene adipate-co-terephthalate.

[0074] The biodegradable nonwoven fabric according to the present invention comprises a biodegradable resin composition, comprising: a first biodegradable resin comprising a diol, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid, wherein, in the biodegradable resin composition, the temperature of the maximum loss tangent by dynamic mechanical analysis is from -40°C to 0°C, and the lowest temperature of the rubbery plateau region is lower than 30°C, wherein the rubbery plateau region is higher than the temperature of the maximum loss tangent, and the rate of change of the loss tangent is at a temperature lower than 0.025 / 10°C.

[0075] The biodegradable resin composition according to the present invention comprises a first biodegradable resin, the first biodegradable resin comprising a diol, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid, and having a first irreversible strain rate of less than 30% as measured by the following measuring method 3:

[0076] [Measuring method 3]

[0077] 1) While the biodegradable resin composition is placed between a pair of flat stainless steel molds, it is compressed at 200°C under a pressure of 20 Mpa to produce a sheet of the biodegradable resin composition with a thickness of 300 μm;

[0078] 2) The sheet of the biodegradable resin composition is cut to produce a sample, the sample comprising a test piece having a width of 3.18 mm and a length of 25 mm;

[0079] 3) The test piece is pulled in the longitudinal direction at a speed of 10 mm / min at room temperature, where the test piece is pulled 40% more than its total length,

[0080] 4) In a state without external force, the test piece is restored at room temperature for 5 minutes;

[0081] 5) The first irreversible strain rate is obtained from the following equation 1:

[0082] [Equation 1]

[0083] First irreversible strain rate = (length of the restored test segment - 25 mm) / 25 mm.

[0084] The biodegradable resin composition according to the present invention comprises a first biodegradable resin, the first biodegradable resin comprising a diol, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid, and having a temperature of the maximum loss tangent of from -40°C to 0°C by dynamic mechanical analysis. Here, the lowest temperature of the rubbery plateau region is lower than 30°C, the rubbery plateau region is higher than the maximum loss tangent, and the rate of change of the loss tangent is at a temperature less than 0.025 / 10°C.

[0085] The biodegradable nonwoven fabric according to the present invention comprises a biodegradable resin composition, the biodegradable resin composition comprising a first biodegradable resin, the first biodegradable resin comprising a diol, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid, and having a temperature of the maximum loss tangent from -40 °C to 0 °C as measured by the following measuring method 7. In the biodegradable nonwoven fabric, the lowest temperature of the rubbery plateau region is lower than 30 °C.

[0086] [Measuring method 7]

[0087] 1) While the biodegradable resin composition is placed between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a sheet of the biodegradable resin composition having a thickness of 300 μm;

[0088] 2) The sheet of the biodegradable resin composition is cut to produce a sample, the sample comprising a test piece having a width of 5 mm and a length of 12 mm;

[0089] 3) By dynamic mechanical analysis, the loss tangent of the test piece is measured at the temperature during the temperature rise from -40 °C to 80 °C;

[0090] 4) The temperature having the maximum value of the loss tangent is the temperature of the maximum loss tangent;

[0091] 5) The temperature range in which the rate of change of the loss tangent is less than 0.025 / 10 °C is the rubbery plateau region.

[0092] Advantageous effects

[0093] According to the present invention, the biodegradable resin composition can have such an isothermal crystallization time that allows it to be made into a nonwoven fabric by a spinning process by selecting the type of the biodegradable resin and adjusting the content of the crystallization promoter. Therefore, the biodegradable resin composition has excellent spinning ability, thereby suppressing the fiber breakage phenomenon in the spinning process. In addition, the biodegradable resin composition also has excellent injection moldability, so that during the injection process, the demolding performance is excellent and the shape of the injection molded product can be maintained. In addition, the biodegradable resin composition has excellent foaming properties, so that when manufacturing a molded product, the foaming ratio can be increased and uniform sizes of the foam cells and a uniform thickness of the molded product can be achieved. In addition, the biodegradable molded product made of the biodegradable resin composition has excellent mechanical properties and can be naturally biodegradable, so that there is no need to incinerate or emit harmful substances.

[0094] Since the biodegradable resin composition according to the present invention and the biodegradable nonwoven fabric including the same include a biodegradable resin, when the life of the biodegradable nonwoven fabric ends, it can be naturally biodegradable, thus eliminating the need for incineration or emission of harmful substances. Since the biodegradable resin composition according to the present invention can be made into ultrafine fibers, the biodegradable nonwoven fabric containing ultrafine fibers can have a soft texture. In addition, since the irreversible strain rate of the biodegradable nonwoven fabric is within a certain range or below a certain range and has a rubbery plateau region within the temperature range where nonwoven fabrics generally are, it can have excellent elasticity. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Figure 1 Schematically illustrates an apparatus for preparing a biodegradable resin composition according to an embodiment.

[0096] Figure 2 Schematically illustrates a process for manufacturing a sheet of a biodegradable resin composition according to an embodiment.

[0097] Figure 3 Schematically illustrates a method for measuring the irreversible strain rate of a test piece according to an embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0098] The description of the structure or function of the embodiments disclosed in this specification or this application is merely shown for the purpose of explaining the embodiments according to the technical idea of the present invention. The embodiments according to the technical idea of the present invention can be implemented in various forms other than the embodiments disclosed in this specification or this application, and should not be construed as the technical idea of the present invention being limited to the embodiments described in this specification or this application.

[0099] In this specification or this application, when "comprising" a certain component, this means including only this component, or this component may further include other components, unless there is a different disclosure. In addition, it should be understood that, unless otherwise specified, in all cases, all numerical ranges representing physical property values, dimensions, etc. of the components described in this specification or this application are modified by the term "about". In addition, in this specification or this application, "ppm" is based on weight. In addition, in this specification or this application, "A and / or B" means "A, B, or A and B".

[0100] The biodegradable resin composition according to the present invention includes a first biodegradable resin, and the first biodegradable resin includes a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid.

[0101] The diol can be an aliphatic diol. The diol can be a bio-based diol. The diol can be at least one selected from the group consisting of: ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 2,2-diethyl-1,3-propanediol, 2-ethyl-2-isobutyl-1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,6-hexanediol, 2-ethyl-1,3-hexanediol, 2,4-dimethyl-2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,6-hexanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-octadecanediol and their derivatives.

[0102] The diol can be at least one selected from the group consisting of 1,4-butanediol, 1,2-ethylene glycol, 1,3-propanediol, diethylene glycol, neopentyl glycol or their derivatives.

[0103] The diol can be at least one selected from the group consisting of 1,4-butanediol, 1,2-ethylene glycol, 1,3-propanediol and their derivatives.

[0104] The diol can include 1,4-butanediol or its derivatives.

[0105] The aromatic dicarboxylic acid can be at least one selected from the group consisting of: phthalic acid, terephthalic acid, isophthalic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 4,4'-biphenyldicarboxylic acid, 4,4'-biphenyletherdicarboxylic acid, anthracenedicarboxylic acid, phenanthrenedicarboxylic acid and their derivatives.

[0106] The aromatic dicarboxylic acid can be at least one selected from the group consisting of: terephthalic acid, dimethyl terephthalate, 2,6-naphthalenedicarboxylic acid, isophthalic acid and their derivatives.

[0107] The aromatic dicarboxylic acid can include terephthalic acid, dimethyl terephthalate or their derivatives.

[0108] The aliphatic dicarboxylic acid can be at least one selected from the group consisting of: oxalic acid, malonic acid, succinic acid, maleic acid, fumaric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid and their derivatives.

[0109] The aliphatic dicarboxylic acid can be at least one selected from the group consisting of adipic acid, succinic acid, sebacic acid and their derivatives.

[0110] The aliphatic dicarboxylic acid may include adipic acid or its derivatives.

[0111] The molar ratio of the first repeating unit: the second repeating unit and the third repeating unit may be 1:0.9 to 1:1.1. The molar ratio of the first repeating unit: the second repeating unit and the third repeating unit may be 1:0.95 to 1:1.05. The molar ratio of the first repeating unit: the second repeating unit and the third repeating unit may be 1:0.98 to 1:1.03.

[0112] The molar ratio of the second repeating unit: the third repeating unit may be 3:7 to 7:3. The molar ratio of the second repeating unit: the third repeating unit may be 3.3:6.7 to 6.7:3.3. The molar ratio of the second repeating unit: the third repeating unit may be 4:6 to 6:4. The molar ratio of the second repeating unit: the third repeating unit may be 4.2:5.8 to 5:5.

[0113] When this range is satisfied, the spinning ability of the biodegradable resin composition can be improved.

[0114] The first biodegradable resin may include a first repeating unit derived from 1,4-butanediol in a content of about 90 mol% or more based on the total diol. The first biodegradable resin may include a first repeating unit derived from 1,4-butanediol in a content of about 95 mol% or more based on the total diol. The first biodegradable resin may include a first repeating unit derived from 1,4-butanediol in a content of about 98 mol% or more based on the total diol.

[0115] The first biodegradable resin may include a second repeating unit derived from terephthalic acid or dimethyl terephthalate in a content of about 30 mol% to about 70 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a second repeating unit derived from terephthalic acid or dimethyl terephthalate in a content of about 35 mol% to about 65 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a second repeating unit derived from terephthalic acid or dimethyl terephthalate in a content of about 40 mol% to about 60 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a second repeating unit derived from terephthalic acid or dimethyl terephthalate in a content of about 43 mol% to about 53 mol% based on the total dicarboxylic acid.

[0116] The first biodegradable resin may include a third repeating unit derived from adipic acid in an amount of about 30 mol% to about 70 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a third repeating unit derived from adipic acid in an amount of about 35 mol% to about 65 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a third repeating unit derived from adipic acid in an amount of about 40 mol% to about 60 mol% based on the total dicarboxylic acid. The first biodegradable resin may include a third repeating unit derived from adipic acid in an amount of about 47 mol% to about 57 mol% based on the total dicarboxylic acid.

[0117] The biodegradable resin composition may further include at least one second biodegradable resin selected from the group consisting of: polybutylene succinate, polylactic acid, polybutylene adipate, polybutylene adipate-co-succinate, polybutylene terephthalate succinate, polyhydroxybutyrate-valerate, polycaprolactone, polybutylene adipate-co-butylene terephthalate succinate, and polybutylene adipate terephthalate succinate.

[0118] The weight ratio of the first biodegradable resin to the second biodegradable resin may be 1:99 to 30:70, 2:98 to 30:70, 3:97 to 30:70, 4:96 to 30:70, or 5:95 to 30:70. When within this range, the biodegradable resin composition may have excellent spinning ability during the spinning process, and the produced biodegradable nonwoven fabric may have improved tensile strength and elongation.

[0119] Preferably, the second biodegradable resin may include polylactic acid.

[0120] The polylactic acid may be a high melting point polylactic acid having a stereocomplex crystal. In addition, the polylactic acid may be formed by solution mixing or melt mixing of poly-L-lactic acid and poly-D-lactic acid.

[0121] The polylactic acid may include units represented by the following formula 1:

[0122] [Formula 1]

[0123]

[0124] The polylactic acid may be a polymer including L-lactic acid units and / or D-lactic acid units. The polylactic acid may include poly-L-lactic acid and / or poly-D-lactic acid.

[0125] Poly-L-lactic acid may be a polymer mainly comprising L-lactic acid units. Poly-L-lactic acid may include L-lactic acid units in an amount of about 90 mol% to about 100 mol%, about 95 mol% to about 100 mol%, or about 97 mol% to about 100 mol%. Poly-L-lactic acid may include D-lactic acid units and / or units other than lactic acid. Poly-L-lactic acid may include D-lactic acid units and / or units other than lactic acid in an amount of about 0 mol% to about 10 mol%, about 0 mol% to about 5 mol%, or about 0 mol% to about 3 mol%.

[0126] Poly-D-lactic acid may be a polymer mainly comprising D-lactic acid units. Poly-D-lactic acid may include D-lactic acid units in an amount of about 90 mol% to about 100 mol%, about 95 mol% to about 100 mol%, or about 97 mol% to about 100 mol%. Poly-D-lactic acid may include L-lactic acid units and / or units other than lactic acid. Poly-D-lactic acid may include L-lactic acid units and / or units other than lactic acid in an amount of about 0 mol% to about 10 mol%, about 0 mol% to about 5 mol%, or about 0 mol% to about 3 mol%.

[0127] Units other than lactic acid may include units derived from dicarboxylic acids, polyols, hydroxycarboxylic acids, and lactones, which have functional groups capable of forming two or more ester bonds, and units derived from various polyesters, various polyethers, and various polycarbonates composed of these various components.

[0128] For example, dicarboxylic acids may include succinic acid, adipic acid, azelaic acid, sebacic acid, terephthalic acid, isophthalic acid, etc. Polyols may include aliphatic polyols such as ethylene glycol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, octylene glycol, glycerol, sorbitol, neopentyl glycol, diethylene glycol, triethylene glycol, polyethylene glycol, and polypropylene glycol, and aromatic polyols obtained by adding ethylene oxide to bisphenol, etc.

[0129] Hydroxycarboxylic acids may include glycolic acid, hydroxybutyric acid, etc. For example, lactones may include glycolide, ε-caprolactone glycolide, ε-caprolactone, β-propiolactone, δ-butyrolactone, β- or γ-butyrolactone, neopentyl lactone, δ-valerolactone, etc.

[0130] Poly-lactic acid can be commercially obtained from Biomer under the name BIOMER TM L9000. In addition, poly-lactic acid can be obtained from Natureworks LLC or Mitsui Chemical (LACEA TM)Commercially obtained. In addition, polylactic acid can be found in U.S. Patent Nos. 4,797,468; 5,470,944; 5,770,682; 5,821,327; 5,880,254; and 6,326,458, the entire contents of which are hereby incorporated by reference for all purposes into the present invention.

[0131] The melting temperature (Tm) of polylactic acid can be from about 100 °C to about 240 °C. The melting temperature of polylactic acid can be from about 120 °C to about 220 °C. The melting temperature of polylactic acid can be from about 140 °C to about 200 °C. The melting temperature of polylactic acid can be from about 140 °C to about 180 °C.

[0132] The crystallization temperature (Tc) of polylactic acid can be from about 50 °C to about 80 °C. The crystallization temperature of polylactic acid can be from about 55 °C to about 75 °C.

[0133] The glass transition temperature (Tg) of polylactic acid can be from about 20 °C to about 80 °C. The glass transition temperature of polylactic acid can be from about 30 °C to about 70 °C. The glass transition temperature of polylactic acid can be from about 40 °C to about 65 °C. The melting temperature and the glass transition temperature can be measured by differential scanning calorimetry (DSC) according to ASTM D - 3417.

[0134] When polylactic acid has a melting temperature and a glass transition temperature within this range, it can be easily extruded. In addition, when polylactic acid has a melting temperature and a glass transition temperature within this range, the biodegradable non - woven fabric made therefrom can have improved mechanical properties.

[0135] The biodegradable resin composition according to the present invention can include a crystallization promoter, and based on the total weight of the biodegradable resin composition, it can include a crystallization promoter in an amount of 100 ppm to 50,000 ppm. Based on the total weight of the biodegradable resin composition, it can include a crystallization promoter in the following amounts: 100 ppm to 50,000 ppm, 100 ppm to 40,000 ppm, 100 ppm to 30,000 ppm, 100 ppm to 10,000 ppm, or 100 ppm to 6,000 ppm.

[0136] The crystallization promoter can be mixed during the polymerization reaction of the first biodegradable resin and / or during the compounding process with the first biodegradable resin.

[0137] In addition, when the biodegradable resin composition includes a crystallization promoter within the content range, it can have an appropriate isothermal crystallization time so that it can be made into a non - woven fabric by a spinning process.

[0138] Therefore, the biodegradable resin composition has excellent spinning ability, thereby suppressing fiber breakage in the spinning process.

[0139] In addition, the biodegradable resin composition also has excellent injection moldability. Therefore, during the injection process, the demolding performance is excellent, and the shape of the injection molded product can be maintained.

[0140] In addition, the biodegradable resin composition has excellent foaming properties. Therefore, when manufacturing biodegradable molded products, the foaming ratio can be increased, and uniform cell sizes of the foam and uniform thickness of the molded product can be achieved.

[0141] The crystallization promoter may include at least one of an organic nucleating agent and an inorganic nucleating agent.

[0142] The organic nucleating agent may refer to a nucleating agent composed of organic compounds.

[0143] The content of the organic nucleating agent that the biodegradable resin composition may include is 10 ppm to 5,000 ppm, 10 ppm to 3,000 ppm, 10 ppm to 1,000 ppm, or 100 ppm to 500 ppm.

[0144] The organic nucleating agent may include nanocellulose with an average length of 10 nm to 300 nm, 10 nm to 200 nm, 20 nm to 200 nm, or 30 nm to 200 nm.

[0145] Based on the total weight of the biodegradable resin composition, the content of nanocellulose may be 10 ppm to 500 ppm, 50 ppm to 500 ppm, 50 ppm to 300 ppm, or 50 ppm to 200 ppm. When this range is satisfied, the crystallization rate can be increased so that fiber-to-fiber fusion can be suppressed in the spinning process, thereby enabling denier control. In addition, during the injection process, the demolding performance is excellent, and the shape of the injection molded product can be maintained. In addition, during the foaming process, the foaming ratio can be increased, and uniform cell sizes of the foam and uniform thickness of the molded product can be achieved.

[0146] The nanocellulose can be pretreated by a bead mill or ultrasonically. The nanocellulose can be pretreated by a bead mill and ultrasonically. The nanocellulose is preferably ultrasonically pretreated after being pretreated by a bead mill, which can prevent re-agglomeration and thus improve the dispersibility.

[0147] A vertical mill or a horizontal mill can be used as a wet grinding device for bead mill pretreatment. The horizontal mill is preferred because it can fill a larger amount of beads inside the chamber, reduce uneven wear of the machine, reduce bead wear, and make maintenance easier, but the present invention is not limited thereto.

[0148] The bead mill pretreatment can be carried out using beads made of one or more selected from the group consisting of zircon, zirconia, quartz, and alumina.

[0149] The bead mill pretreatment can be carried out using beads with a diameter of about 0.3 mm to about 1 mm. For example, the diameter of the beads can be about 0.3 mm to about 0.9 mm, about 0.4 mm to about 0.8 mm, about 0.45 mm to about 0.7 mm, or about 0.45 mm to about 0.6 mm. When this range is satisfied, the nanocellulose can have improved dispersibility.

[0150] Ultrasonic pretreatment is a method of physically breaking or pulverizing nanoparticles by waves generated by emitting 20 kHz ultrasonic waves into a solution.

[0151] The ultrasonic pretreatment can be carried out for less than 30 minutes at an output of 30,000 J / s or less. For example, the ultrasonic pretreatment can be carried out for 25 minutes or less, 20 minutes or less, or 18 minutes or less at an output of 25,000 J / s or less or 22,000 J / s or less. When this range is satisfied, the ultrasonic pretreatment effect, i.e., the improvement of dispersibility, can be maximized.

[0152] The inorganic nucleating agent can refer to a nucleating agent composed of inorganic compounds.

[0153] The content of the inorganic nucleating agent that the biodegradable resin composition can include is 100 ppm to 10,000 ppm, 100 ppm to 8,000 ppm, 300 ppm to 8,000 ppm, 500 ppm to 8,000 ppm, or 500 ppm to 6,000 ppm. When this range is satisfied, the fiber breakage phenomenon during the spinning process can be inhibited, and the spinning process can proceed smoothly. In addition, during the injection process, the demolding performance is excellent, and the shape of the injection molded product can be maintained. In addition, during the foaming process, the foaming ratio can be increased, and a uniform cell size of the foam and a uniform thickness of the molded product can be achieved.

[0154] The inorganic nucleating agent can include one or more selected from the group consisting of titanium dioxide, talc, kaolinite, montmorillonite, mica, clay, zeolite, silica, graphite, carbon black, mica, barium sulfate, calcium silicate, calcium carbonate, calcium sulfide, calcium titanate, zinc oxide, alumina, magnesia, neodymium oxide, and boron nitride.

[0155] The inorganic nucleating agent may include at least one of rutile-phase titanium dioxide and anatase-phase titanium dioxide.

[0156] Preferably, the inorganic nucleating agent may include anatase-phase titanium dioxide. Anatase-phase titanium dioxide exhibits high photoactivity and thus can further improve biodegradability.

[0157] The inorganic nucleating agent may have an average diameter (D 50 ) of 0.1 μm to 0.5 μm, 0.1 μm to 0.4 μm, 0.15 μm to 0.4 μm, 0.15 μm to 0.3 μm, or 0.15 μm to 0.25 μm. When within this range, the kneading characteristics of the first biodegradable resin and the mechanical strength of the biodegradable resin composition can be improved.

[0158] The biodegradable resin composition may further include an external lubricant.

[0159] The external lubricant reduces the heat generated by friction during mixing, melting, and processing of the raw materials, has an excellent dispersion effect on the first biodegradable resin, and has an excellent lubricating effect, thereby improving manufacturing efficiency.

[0160] The external lubricant may be selected from the group consisting of carbodiimide-based lubricants, ester-based lubricants, amide-based lubricants, paraffin-based lubricants, and stearic acid-based lubricants.

[0161] The external lubricant may include a stearic acid-based lubricant.

[0162] As the external lubricant, calcium stearate and / or octadecyl stearate may be used.

[0163] The content of the external lubricant that the biodegradable resin composition may include is 100 ppm to 5,000 ppm, 200 ppm to 5,000 ppm, 200 ppm to 4,000 ppm, 200 ppm to 3,000 ppm, 200 ppm to 2,000 ppm, 300 ppm to 2,000 ppm, 400 ppm to 2,000 ppm, or 500 ppm to 2,000 ppm. When within this range, manufacturing efficiency can be improved without deteriorating the mechanical properties of the biodegradable resin composition.

[0164] The biodegradable resin composition may include a branching agent, which includes at least one of a trivalent or higher-valent alcohol and a trivalent or higher-valent carboxylic acid. The branching agent can react with diols, aliphatic dicarboxylic acids, and / or aromatic dicarboxylic acids. The branching agent may be included as part of the molecular structure of the first biodegradable resin.

[0165] The trivalent or higher alcohol may be at least one selected from the group consisting of glycerol, pentaerythritol, and trimethylolpropane.

[0166] The trivalent or higher carboxylic acid may be at least one selected from the group consisting of: methane tricarboxylic acid, ethane tricarboxylic acid, citric acid, benzene-1,3,5-tricarboxylic acid, 5-sulfo-1,2,4-benzenetricarboxylic acid, ethane-1,1,2,2-tetracarboxylic acid, propane-1,1,2,3-tetracarboxylic acid, butane-1,2,3,4-tetracarboxylic acid, cyclopentane-1,2,3,4-tetracarboxylic acid, and benzene-1,2,4,5-tetracarboxylic acid.

[0167] The branching agent may include glycerol.

[0168] Based on the total weight of the biodegradable resin composition, the content of the branching agent may be 500 ppm to 3,000 ppm, 700 ppm to 3,000 ppm, 700 ppm to 2,500 ppm, or 1,000 ppm to 2,000 ppm. When this range is satisfied, the nonwoven fabric made from the biodegradable resin composition may have appropriate biodegradability and improved mechanical properties.

[0169] The biodegradable resin composition may include a heat stabilizer. The heat stabilizer may be at least one selected from the group consisting of: phosphorus / amine-based high-temperature heat stabilizers such as tetraethylenepentamine, triethyl phosphonoacetate, phosphoric acid, phosphorous acid, polyphosphoric acid, trimethyl phosphate (TMP), triethyl phosphate, trimethylphosphine, triphenylphosphine, etc.

[0170] The heat stabilizer may include triethyl phosphonoacetate.

[0171] Based on the total weight of the biodegradable resin composition, the content of the heat stabilizer may be 10 ppm to 3,000 ppm, 20 ppm to 2,000 ppm, 20 ppm to 1,500 ppm, or 20 ppm to 1,000 ppm. When this range is satisfied, the polymer degradation caused by high temperature during the reaction can be controlled so that the end groups of the polymer can be reduced and the color can be improved.

[0172] According to the following Measuring Method 1, the isothermal crystallization time of the biodegradable resin composition at 90 °C is 10 seconds to 900 seconds:

[0173] [Measuring Method 1]

[0174] 1) Heat the biodegradable resin composition to 220 °C at a heating rate of 10 °C / min, and then hold for 5 minutes;

[0175] 2) Next, the biodegradable resin composition was cooled to 90°C at a cooling rate of 100°C / min and then held isothermally for 100 minutes;

[0176] 3) The half-time of the total area of the crystallization peak of the biodegradable resin composition was measured using differential scanning calorimetry.

[0177] The isothermal crystallization time refers to the time required to rapidly cool the biodegradable resin composition in a molten state and evaluate it until crystallization occurs.

[0178] A short isothermal crystallization time indicates that crystallization proceeds rapidly. Rapid crystallization may mean that molecular motion is inhibited and crystals are formed in a rapid stage after cooling.

[0179] The isothermal crystallization time can be adjusted according to the presence or absence of the above-mentioned crystallization promoter and its content.

[0180] When the biodegradable resin composition has an isothermal crystallization time according to Measuring Method 1, this means that the biodegradable resin composition has a crystallization rate that enables it to be produced into a nonwoven fabric by a spinning process, and at the same time, fiber-to-fiber fusion and fiber breakage phenomena during the spinning process can be inhibited.

[0181] Furthermore, when the biodegradable resin composition has an isothermal crystallization time according to Measuring Method 1, this means that the biodegradable resin composition has a crystallization rate that enables it to be produced into an injection-molded product by an injection molding process, and at the same time, the demolding property in the injection molding process is excellent, and the shape of the injection-molded product can be maintained.

[0182] Furthermore, when the biodegradable resin composition has an isothermal crystallization time according to Measuring Method 1, this means that the biodegradable resin composition has a crystallization rate that enables it to be produced into a foam-molded product by a foaming process, and at the same time, the foaming ratio can be increased, and uniform cell sizes of the foam and a uniform thickness of the molded product can be achieved.

[0183] Furthermore, when the biodegradable resin composition has an isothermal crystallization time according to Measuring Method 1, this means that the nonwoven fabric, injection-molded product, and foam-molded product made of the biodegradable resin composition have improved mechanical properties.

[0184] According to Measuring Method 1, the isothermal crystallization time of the biodegradable resin composition at 90°C can be from 40 seconds to 800 seconds. Preferably, according to Measuring Method 1, the isothermal crystallization time of the biodegradable resin composition at 90°C can be from 41 seconds to 795 seconds, from 40 seconds to 790 seconds, from 40 seconds to 785 seconds, or from 41 seconds to 784 seconds. When this range is satisfied, the biodegradable resin composition has excellent spinning ability, thereby suppressing fiber breakage during the spinning process. In addition, the biodegradable resin composition also has excellent injection moldability. Therefore, during the injection process, the demolding performance is excellent, and the shape of the injection-molded product can be maintained. In addition, the biodegradable resin composition has excellent foaming properties. Therefore, when manufacturing biodegradable molded products, the foaming ratio can be increased, and uniform cell sizes of the foam and uniform thickness of the molded product can be achieved. In addition, the biodegradable molded products made from the biodegradable resin composition can have improved mechanical properties.

[0185] According to Measuring Method 1, when the biodegradable resin composition is cooled to 70°C (instead of 90°C), the isothermal crystallization time can be 240 seconds or shorter, 200 seconds or shorter, 180 seconds or shorter, or 130 seconds or shorter.

[0186] According to Measuring Method 1, when the biodegradable resin composition is cooled to 50°C (instead of 90°C), the isothermal crystallization time can be 120 seconds or shorter, 100 seconds or shorter, 80 seconds or shorter, or 60 seconds or shorter.

[0187] When this range is satisfied, non-woven fabrics, injection-molded products, and foam-molded products can be made from the biodegradable resin composition, and the mechanical properties can be improved.

[0188] As measured by differential scanning calorimetry, the biodegradable resin composition can have a crystallization temperature (Tc) of 35°C to 90°C, 40°C to 90°C, 45°C to 90°C, 45°C to 85°C, or 50°C to 83°C.

[0189] The biodegradable resin composition can have a melting temperature (Tm). The melting temperature can be measured by differential scanning calorimetry. The biodegradable resin composition can have a melting temperature of 100°C to 180°C, 100°C to 150°C, 110°C to 130°C, or 119°C to 124°C.

[0190] The biodegradable resin composition can have a glass transition temperature (Tg). The glass transition temperature can be measured by differential scanning calorimetry. The biodegradable resin composition can have a glass transition temperature of -50°C to 0°C, -40°C to 0°C, -40°C to -20°C, or -33°C to -28°C.

[0191] The biodegradable resin composition, as measured at 190 °C and 2.16 kg, may have a melt flow rate of 2 g / 10 min to 60 g / 10 min, 2 g / 10 min to 50 g / 10 min, 3 g / 10 min to 50 g / 10 min, or 4 g / 10 min to 45 g / 10 min.

[0192] When the crystallization temperature range, melting temperature range, and glass transition temperature range are satisfied, the discharge amount of the biodegradable resin composition is uniform during the spinning process, exhibiting excellent spinning ability, having excellent mold release properties during the injection molding process, and the cell pores formed during the foaming process may have a uniform size.

[0193] According to Measurement Method 2 below, the biodegradable resin composition may have a tensile strength of 25 MPa or greater, 27 MPa or greater, 29 MPa or greater, 31 MPa or greater, or 31 MPa or greater to 50 MPa or less:

[0194] [Measurement Method 2]

[0195] 1) Prepare a specimen with a thickness of 300 μm from the biodegradable resin composition;

[0196] 2) Measure the tensile strength of the specimen using a universal testing machine at a rate of 100 mm / min.

[0197] The elongation at break of the specimen measured using a universal testing machine may be 800% to 1,200%, 800% to 1,100%, 800% to 1,000%, 800% to 950%, or 805% to 940%.

[0198] The tensile strength and elongation at break of the biodegradable resin composition may be indicators representing the mechanical properties of the biodegradable resin composition. The tensile strength and elongation at break of the biodegradable resin composition may depend on the presence or absence and content of the above-mentioned crystallization promoter. When this range is satisfied, bead formation in the biodegradable molded article can be suppressed, and the biodegradable molded article can have appropriate mechanical strength.

[0199] Figure 1 Schematically illustrates an apparatus for manufacturing a biodegradable resin composition according to an embodiment. Refer to Figure 1 , the apparatus may include a slurry stirrer 100, an esterification reaction section 200, a polycondensation reaction section 300, a post-treatment section 400, a first recovery section 510, and a second recovery section 520.

[0200] The step of preparing the biodegradable resin composition may include the step of preparing a slurry including a diol and an aromatic dicarboxylic acid.

[0201] This step may include the step of mixing and processing the diol and the aromatic dicarboxylic acid.

[0202] This step may be a pretreatment step before the esterification reaction and the step of mixing and pulping the diol and the aromatic dicarboxylic acid. Here, the diol may include a biomass-based diol component.

[0203] The diol and the aromatic dicarboxylic acid may be fed into the slurry stirrer 100 and stirred therein to produce a slurry. By mixing and pretreating the diol and the aromatic dicarboxylic acid to form a slurry, the diol and the aromatic dicarboxylic acid can react uniformly, and this is effective in accelerating the esterification reaction, thereby improving the reaction efficiency. In particular, when an aromatic dicarboxylic acid such as terephthalic acid has complete crystallinity and is in powder form, its solubility in the diol is extremely low, making it difficult to occur a homogeneous reaction. Therefore, the pretreatment process of pulping can play a very important role in achieving the excellent physical properties of the biodegradable nonwoven fabric according to the present invention.

[0204] When the aromatic dicarboxylic acid is terephthalic acid, terephthalic acid has perfect crystallinity and is a white crystal, which sublimes at about 300 °C under normal pressure without a melting point, so its solubility in the diol is extremely low, making it difficult to occur a homogeneous reaction. Therefore, when the pretreatment process is carried out before esterification, a uniform reaction can be induced by increasing the surface area for reacting with the diol in the solid matrix of terephthalic acid.

[0205] When the aromatic dicarboxylic acid is dimethyl terephthalate, dimethyl terephthalate can be made into a molten state at about 142 °C to 170 °C by the pretreatment process and react with the diol, so that the esterification can proceed faster and more effectively.

[0206] Meanwhile, in the pretreatment step of preparing the slurry, the structure and properties of the biodegradable resin composition may vary according to the particle size, particle size distribution, pretreatment reaction conditions, etc. of the aromatic dicarboxylic acid.

[0207] The aromatic dicarboxylic acid may include terephthalic acid. In the particle size distribution (PSD), the terephthalic acid may have an average particle size (D50) of 10 μm to 400 μm, measured by a particle size analyzer Microtrac S3500, and may have a standard deviation of 100 or less for the average particle size (D50). The standard deviation means the square root of the variance. The average particle size (D50) of terephthalic acid may be 20 μm to 200 μm, 30 μm to 180 μm, or 50 μm to 150 μm. When the average particle size (D50) of terephthalic acid satisfies these ranges, it may be more advantageous in terms of improving the solubility and reaction rate in diol.

[0208] In the pretreatment process, the diol and the aromatic dicarboxylic acid can be mixed and fed into the slurry stirrer (tank) 100.

[0209] The slurry stirrer 100 may have an anchor - type bottom and a height of 20 mm or more from the stirrer. In addition, the slurry stirrer 100 may be equipped with two or more rotating blades, which may be more advantageous in achieving an effective stirring effect.

[0210] The height from the slurry stirrer 100 may be 20 mm or more, that is, the supply line and the bottom of the stirrer can be almost connected to each other. In this case, the slurry can be obtained without precipitation. If the shape, form, and rotating blades of the stirrer do not meet the above conditions, the aromatic dicarboxylic acid may deposit on the bottom when the diol and the aromatic dicarboxylic acid are initially mixed. In this case, phase separation may occur.

[0211] The pretreatment process for preparing the slurry may include the following steps: mixing the diol and the aromatic dicarboxylic acid, and stirring at about 30 °C to about 100 °C at about 50 rpm to about 200 rpm for 10 minutes or longer, or 10 minutes to 200 minutes.

[0212] The diol may have the above - mentioned characteristics.

[0213] The diol can be added in batches or portions.

[0214] The diol can be added in portions when mixing with the aromatic dicarboxylic acid and when mixing with the aliphatic dicarboxylic acid. The aromatic dicarboxylic acid may have the above - mentioned characteristics. In the pretreatment step of preparing the slurry, the molar ratio of the diol to the aromatic dicarboxylic acid may be about 0.8:1 to about 1.2:1. In the pretreatment step of preparing the slurry, the molar ratio of the diol to the aromatic dicarboxylic acid may be about 0.9:1 to about 1.1:1. When the diol is added in an amount greater than that of the aromatic dicarboxylic acid, the aromatic dicarboxylic acid can be easily dispersed.

[0215] This step may include the step of esterifying a slurry and an aliphatic dicarboxylic acid to prepare a prepolymer. The slurry and the aliphatic dicarboxylic acid may react in an esterification reaction section 200. In the esterification, the reaction time may be shortened by using the slurry.

[0216] The slurry obtained from the pretreatment step may shorten the reaction time of esterification by 1.5 times or more. The esterification may be carried out at least twice. The prepolymer to be added to the polycondensation process may be formed by esterification.

[0217] For example, esterification may be carried out immediately after adding an aliphatic dicarboxylic acid or a glycol and an aliphatic dicarboxylic acid to the slurry. That is, esterification may be carried out when the slurry is fed into the esterification reactor, and when only the aliphatic dicarboxylic acid or the aliphatic dicarboxylic acid and the glycol are fed into the esterification reactor.

[0218] The esterification may be carried out at about 250 °C or lower for about 0.5 hour to about 5 hours. In particular, the esterification may be carried out at normal pressure or reduced pressure at about 180 °C to about 250 °C, about 185 °C to about 240 °C or about 200 °C to about 240 °C until the theoretical amount of water as a by-product reaches 95%. For example, the esterification may be carried out for 0.5 hour to 5.5 hours, 0.5 hour to 4.5 hours or 1 hour to 4 hours, but is not limited thereto.

[0219] The slurry may be mixed with at least one of a polycarbonate diol and a polyether polyol to carry out a first esterification reaction. Alternatively, the polycarbonate diol and the polyether polyol may be introduced into a second esterification.

[0220] In addition, after the first esterification, a mixture of an aliphatic dicarboxylic acid and a glycol may be fed into the esterification reaction section 200 and may be subjected to a second esterification together with the first esterification product. In addition, at least one of a polycarbonate diol and a polyether polyol may be added to the second esterification.

[0221] The first esterification reaction may be carried out at 250 °C or lower for 1.25 hours to 4 hours. In particular, the first esterification reaction may be carried out at normal pressure or reduced pressure until the water as a by-product theoretically reaches 95% at 180 °C to 250 °C, 185 °C to 240 °C or 200 °C to 240 °C. For example, the first esterification reaction may be carried out for 1.25 hours to 4 hours, 1.25 hours to 3.5 hours or 2.5 hours to 3 hours, but the present invention is not limited thereto.

[0222] The second esterification reaction can be carried out at about 250 °C or lower for 0.25 hours to 3.5 hours. In particular, the second esterification reaction can be carried out under normal pressure or reduced pressure until the water as a by-product theoretically reaches 95% at 180 °C to 250 °C, 185 °C to 240 °C or 200 °C to 240 °C. For example, the second esterification reaction can be carried out for 0.5 hours to 3 hours, 1 hour to 2.5 hours or 1.5 hours to 2.5 hours, but the present invention is not limited thereto.

[0223] When the esterification is divided into a first esterification and a second esterification, the total esterification can be precisely controlled. Therefore, when the esterification is carried out in a divided manner, the reaction stability and reaction uniformity of the esterification can be improved.

[0224] Through the esterification reaction, a prepolymer can be formed.

[0225] The number average molecular weight of the prepolymer can be about 500 g / mol to about 10,000 g / mol. For example, the number average molecular weight of the prepolymer can be about 500 g / mol to about 8,500 g / mol, about 500 g / mol to about 8,000 g / mol, about 500 g / mol to about 7,000 g / mol, about 500 g / mol to about 5,000 g / mol or about 800 g / mol to about 3,000 g / mol. When the number average molecular weight of the prepolymer satisfies this range, the molecular weight of the polymer can be effectively increased in the polycondensation reaction.

[0226] The number average molecular weight can be measured using gel permeation chromatography (GPC). In particular, the data generated by gel permeation chromatography includes several items such as Mn, Mw and Mp, but the molecular weight can be measured based on the number average molecular weight (Mn).

[0227] Before the esterification reaction, a crystallization promoter can be added together with the slurry.

[0228] The crystallization promoter can be fed into the esterification reaction section 200 during the esterification reaction.

[0229] After the esterification reaction, the crystallization promoter can be added to the product of the esterification reaction.

[0230] The crystallization promoter can be added together with the aliphatic dicarboxylic acid.

[0231] After the first esterification reaction and before the second esterification reaction, the crystallization promoter can be fed into the esterification reaction section 200. When the crystallization promoter is added to the esterification reaction, the crystallization promoter can be uniformly dispersed in the first biodegradable resin. The crystallization promoter can have the above characteristics.

[0232] In the esterification reaction, a titanium-based catalyst and / or a germanium-based catalyst can be used. In particular, the titanium-based catalyst and / or the germanium-based catalyst can be added to the slurry, and the esterification reaction can be carried out.

[0233] Before the first esterification reaction, the titanium-based catalyst and / or the germanium-based catalyst can be added to the slurry, and the titanium-based catalyst and / or the germanium-based catalyst can be further added to the product of the first esterification reaction.

[0234] Based on the total weight of the diol, the aromatic dicarboxylic acid, and the aliphatic dicarboxylic acid, the content of the catalyst can be about 100 ppm to 2,000 ppm. For example, the content of the included titanium-based catalyst or germanium-based catalyst can be about 100 ppm to about 1,600 ppm, about 150 ppm to about 1,400 ppm, about 200 ppm to about 1,200 ppm, or about 250 ppm to about 1,100 ppm. When the content of the catalyst satisfies this range, the performance can be further improved.

[0235] Before esterification, a heat stabilizer can be added together with the slurry. The heat stabilizer can be fed into the esterification section 200 in the middle stage of esterification. The heat stabilizer can be added to the esterification product after esterification. In addition, the heat stabilizer can be added together with the aliphatic dicarboxylic acid. In addition, the heat stabilizer can be fed into the esterification section 200 after the first esterification and before the second esterification.

[0236] The characteristics of the heat stabilizer can be as described above.

[0237] Based on the total weight of the diol, the aromatic dicarboxylic acid, and the aliphatic dicarboxylic acid, the content of the heat stabilizer can be 3,000 ppm or less. In particular, based on the total weight of the diol, the aromatic dicarboxylic acid, and the aliphatic dicarboxylic acid, the content of the heat stabilizer can be 10 ppm to 3,000 ppm, 20 ppm to 2,000 ppm, 20 ppm to 1,500 ppm, or 20 ppm to 1,000 ppm. When the content of the heat stabilizer satisfies this range, the deterioration of the polymer caused by high temperature during the reaction can be controlled, so the end groups of the polymer can be reduced and the color can be improved.

[0238] After the completion of esterification, one or more selected from the group consisting of additives such as silica, potassium, or magnesium and color correctors such as cobalt acetate can be further added to the esterification product. That is, after the completion of esterification, the additive and / or the color corrector can be added and stabilized, and then the polycondensation reaction can be carried out. The additive and / or the color corrector can be added after the completion of the esterification reaction and can be fed into the polycondensation reaction section 300 together with the prepolymer.

[0239] After the esterification reaction is completed, a crystallization promoter can be added to the product of the esterification reaction. After the esterification reaction is completed, a polycondensation reaction can be carried out after adding and stabilizing the crystallization promoter. The crystallization promoter can be fed together with the prepolymer into the polycondensation reaction section 300, and the polycondensation process can be carried out. Accordingly, the crystallization promoter can be uniformly dispersed in the first biodegradable resin.

[0240] The first recovery section 510 can recover by-products such as water from the esterification reaction section 200. The first recovery section 510 can recover the by-products generated by esterification by applying a vacuum pressure to the esterification reaction section 200 or by performing reflux.

[0241] This step can include a step of carrying out a polycondensation reaction of the prepolymer. The step of carrying out the polycondensation reaction can be carried out as follows. The prepolymer can be fed into the polycondensation reaction section 300. In addition, the crystallization promoter can be fed together with the prepolymer into the polycondensation reaction section 300.

[0242] Next, the polycondensation reaction can be carried out at about 180°C to about 280°C and at about 10 Torr or less for about 1 hour to about 5 hours. For example, the polycondensation reaction can be carried out at about 190°C to about 270°C, about 210°C to about 260°C, or about 230°C to about 255°C, at about 0.9 Torr or lower, about 0.7 Torr or lower, about 0.2 Torr to about 10 Torr, about 0.3 Torr to about 0.9 Torr, or about 0.2 Torr to about 0.6 Torr for about 1.5 hours to about 5 hours, about 2 hours to about 4.5 hours, or about 2 hours to about 4 hours.

[0243] The polycondensation reaction can include a first polycondensation and a second polycondensation.

[0244] For example, the first polycondensation can be carried out at about 260°C or lower, about 250°C or lower, about 215°C to about 250°C, about 215°C to about 245°C, or about 230°C to about 245°C at about 1 Torr to about 200 Torr, about 2 Torr to about 100 Torr, about 4 Torr to about 50 Torr, about 5 Torr to about 45 Torr, or about 8 Torr to about 32 Torr for about 0.5 hours to about 3.5 hours, about 0.5 hours to about 3.0 hours, or about 0.5 hours to about 2.8 hours.

[0245] The second polycondensation can be carried out at about 220°C to about 265°C, about 230°C to about 260°C, or about 235°C to about 255°C at about 1 Torr or less, about 0.8 Torr or less, about 0.6 Torr or less, about 0.1 Torr to about 1 Torr, about 0.2 Torr to about 0.8 Torr, or about 0.2 Torr to about 0.6 Torr for about 0.5 hours to about 4 hours, about 1 hour to about 3.5 hours, or about 1.5 hours to about 3.5 hours.

[0246] Before the polycondensation reaction, a titanium-based catalyst or a germanium-based catalyst can be further added to the prepolymer. In addition, before the polycondensation reaction, one or more selected from the group consisting of additives such as silica, potassium or magnesium; phosphorus / amine stabilizers such as trimethyl phosphate, triphenyl phosphate, trimethylphosphine, phosphoric acid, phosphorous acid or tetraethylenepentamine; and polymerization catalysts such as antimony trioxide or tetrabutyl titanate can be further added to the prepolymer.

[0247] The number average molecular weight of the polymer can be about 20,000 g / mol or more. For example, the number average molecular weight of the polymer can be about 20,000 g / mol or more, about 30,000 g / mol or more, about 40,000 g / mol or more, about 43,000 g / mol or more, about 45,000 g / mol or more, or about 50,000 g / mol to about 70,000 g / mol. When the number average molecular weight of the polymer satisfies this range, the physical properties, impact resistance, durability and moldability can be further improved.

[0248] The second recovery unit 520 can recover by-products such as water from the polycondensation reaction unit 300. The second recovery unit 520 can apply a vacuum pressure to the polycondensation reaction unit 300 and can recover the by-products generated in the polycondensation reaction.

[0249] The second recovery unit 520 can apply a vacuum pressure of about 0.1 Torr to about 1 Torr to the inside of the polycondensation reaction unit 300. The second recovery unit 520 can apply a vacuum pressure of about 0.1 Torr to about 0.9 Torr to the inside of the polycondensation reaction unit 300.

[0250] A chain extender can be added to the polymer. The polymer and the chain extender can be uniformly mixed and held at about 200 °C to about 260 °C for about 1 minute to about 15 minutes.

[0251] This step may include the step of manufacturing pellets from a polymer. In particular, the polymer may be cooled at about 15 °C or lower, about 10 °C or lower, or about 6 °C or lower, and then the cooled polymer may be cut to produce pellets. The cutting step may be carried out using any pellet cutting machine used in the art without limitation, and the pellets may have various shapes. As a pellet cutting method, an underwater cutting method or a strand cutting method may be used. The pellets may undergo an additional post-treatment process. The pellets may be fed into the post-treatment unit 400 and a post-treatment process may be carried out. The post-treatment process may be carried out in the post-treatment unit 400. The pellets may be fed into the post-treatment unit 400. Next, the post-treatment unit 400 may melt and re-extrude the fed pellets by frictional heat. That is, the post-treatment unit 400 may include an extruder such as a twin-screw extruder. The temperature of the post-treatment process may be about 230 °C to about 270 °C. The temperature of the post-treatment process may be about 230 °C to about 260 °C. The temperature of the post-treatment process may be about 240 °C to about 265 °C. The temperature of the post-treatment process may be about 240 °C to about 260 °C. The post-treatment process time may be about 30 seconds to about 3 minutes. The post-treatment process time may be about 50 seconds to about 2 minutes. The post-treatment process time may be about 1 minute to about 2 minutes. Next, the resin extruded from the extruder may be cooled, cut, and processed into post-treated pellets. That is, the resin extruded from the extruder may be reprocessed into pellets through the above-mentioned cutting step. During the post-treatment process, the crystallinity of the pellets may be improved. In addition, the content of the residues included in the pellets may be adjusted during the post-treatment process. In particular, the content of the oligomers included in the pellets may be controlled through the post-treatment process. The amount of the residual solvent included in the pellets may be controlled through the post-treatment process.

[0252] During the post-treatment process, the crystallinity and mechanical properties of the biodegradable resin composition may be appropriately controlled.

[0253] After the production of the pellets, the first biodegradable resin may be compounded with the above-mentioned second biodegradable resin. In addition, a crystallization promoter may be compounded together with the first biodegradable resin and the second biodegradable resin.

[0254] The biodegradable molded article according to the present invention includes a biodegradable resin composition, the biodegradable resin composition including a first biodegradable resin, the first biodegradable resin including a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid, and a crystallization promoter, wherein based on the total weight of the biodegradable resin composition, a crystallization promoter may be included in an amount of 100 ppm to 50,000 ppm, and the isothermal crystallization time at 90 °C is 10 seconds to 900 seconds according to the following measurement method 1:

[0255] [Measurement Method 1]

[0256] 1) Heat the biodegradable resin composition to 220 °C at a heating rate of 10 °C / min and then hold for 5 minutes;

[0257] 2) Then, cool the biodegradable resin composition to 90 °C at a cooling rate of 100 °C / min and maintain the isothermal state for 100 minutes;

[0258] 3) Using differential scanning calorimetry, measure the time when the total area of the crystallization peak of the biodegradable resin composition is halved.

[0259] The biodegradable molded article can be a nonwoven fabric, an injection molded article, or a foam molded article.

[0260] The method for manufacturing a nonwoven fabric may include steps of manufacturing the biodegradable resin composition into biodegradable yarns through a spinning process, cooling the biodegradable yarns, stretching the biodegradable yarns, and combining the cooled biodegradable yarns to form a biodegradable yarn web.

[0261] The spinning process may include the process of melting the biodegradable resin composition and introducing it into a spinning assembly. In the spinning assembly, the molten biodegradable resin composition can be spun from the nozzles of an extruder. Through the spinning assembly, filaments of the biodegradable resin composition can be formed. The filaments can be cooled, solidified, and crystallized to produce unstretched biodegradable yarns.

[0262] Multiple nozzles can be provided. The number of nozzles can be 2 to 30, 10 to 30, or 18 to 30. Through multiple nozzles, multiple filaments can be produced from the biodegradable resin composition. The pressure of the nozzles can be about 80 kg / cm² to 120 kg / cm² 2 to 120 kg / cm² 2 90 kg / cm² 2 to 120 kg / cm² 2 90 kg / cm² 2 to 110 kg / cm² 2 or 95 kg / cm² 2 to 105 kg / cm² 2 . The spinning temperature in the spinning assembly can be 180 °C to 250 °C, 190 °C to 250 °C, 190 °C to 240 °C, or 190 °C to 230 °C.

[0263] The biodegradable resin composition in the spinning process can have a melt flow rate within a specific range.

[0264] The biodegradable resin composition can have a melt flow rate of 2 g / 10 min to 60 g / 10 min, 2 g / 10 min to 50 g / 10 min, 3 g / 10 min to 50 g / 10 min, or 4 g / 10 min to 45 g / 10 min, as measured at 190 °C and 2.16 kg.

[0265] When these ranges are satisfied, the amount of the biodegradable resin composition discharged during the spinning process is uniform, so that excellent spinning ability can be provided. The yarns of the biodegradable nonwoven fabric made from the biodegradable resin composition can be unbroken, and the tensile strength and elongation can be improved.

[0266] This step may include the step of cooling the biodegradable yarn.

[0267] The biodegradable yarn can be an unstretched biodegradable yarn produced from the biodegradable resin composition.

[0268] The cooling can be carried out at about 1 °C to 15 °C, 1 °C to 13 °C, 2 °C to 13 °C, or 5 °C to 13 °C. The cooling can be carried out in a quenching chamber. The length of the quenching chamber can be about 1 m to 5 m, about 1 m to 4 m, about 1 m to 3 m, or about 1 m to 2 m.

[0269] When this range is satisfied, the phenomenon that adjacent unstretched biodegradable yarns fuse together can be suppressed.

[0270] This step may include the step of stretching the cooled biodegradable yarn.

[0271] Through the stretching process, compared with the unstretched biodegradable yarn, biodegradable yarns stretched 1.1 times to 3 times, 1.2 times to 3 times, 1.2 times to 2.7 times, 1.2 times to 2.6 times, or 1.2 times to 2.5 times can be produced.

[0272] The stretched biodegradable yarn can be heat-treated at an appropriate temperature.

[0273] The stretched biodegradable yarn can be wound. The stretched biodegradable yarn can be wound by a winder. The winding speed of the winder can be 300 m / min to 3,000 m / min, 300 m / min to 2,500 m / min, 400 m / min to 2,500 m / min, 500 m / min to 2,500 m / min, or 250 m / min to 2,000 m / min. When this range is satisfied, the phenomenon that the biodegradable yarns fuse or break from each other can be suppressed.

[0274] The tensile strength of the biodegradable yarn can be 0.5 g / de to 5.0 g / de, 0.5 g / de to 4.0 g / de, 0.5 g / de to 4.0 g / de, 1.0 g / de to 4.0 g / de, or 1.0 g / de to 3.0 g / de. The elongation at break of the biodegradable yarn can be 20% to 400%, 20% to 300%, 25% to 300%, 25% to 250%, 30% to 250%, or 35% to 200%. The tensile strength of the biodegradable yarn can be 1.0 g / de to 3.0 g / de, and its elongation at break can be 35% to 200%. When within this range, the biodegradable yarns can be easily compressed together, so they can be easily applied to biodegradable nonwoven fabrics, and the mechanical strength of the biodegradable nonwoven fabrics can be improved.

[0275] The average diameter of the biodegradable yarn can be 1 μm to 500 μm, 1 μm to 400 μm, 1 μm to 300 μm, 1 μm to 200 μm, or 10 μm to 100 μm. When within this range, the biodegradable yarns can be easily pressed together and can be easily used as biodegradable nonwoven fabrics, and the mechanical strength of the biodegradable nonwoven fabrics can be improved.

[0276] This step may include the step of combining the cooled biodegradable yarns to form a biodegradable yarn web.

[0277] The method of combining the biodegradable yarns can be a carding, air-laying, aqueous suspension, or spunbond process.

[0278] The carding process may refer to a process of stacking the biodegradable yarns on a collector using a device including multiple gears to form a biodegradable yarn web.

[0279] The air-laying process may refer to a process of arranging the biodegradable yarns on a collector using a device pushed by an air current to form a biodegradable yarn web.

[0280] The aqueous suspension process may refer to a process of dispersing the biodegradable yarns in water, conveying them on a wire mesh sieve or a perforated drum, and then sucking, pressing, and drying the residual moisture of the transferred biodegradable yarns to form a biodegradable yarn web.

[0281] The spunbond process may refer to a process of forming a Venturiweb of the biodegradable yarns on a collector and then forming a biodegradable yarn web.

[0282] This step may further include the step of combining the biodegradable yarn webs by at least one of the processes of needling, hydroentangling, stitch bonding, calendering, and air-through bonding.

[0283] Through this process, the bonding strength between the biodegradable yarn webs can be enhanced, the tensile strength and elongation can be improved, and the biodegradable nonwoven fabric can be prevented from fuzzing.

[0284] The needling process may refer to a process in which needles penetrate the biodegradable yarn webs and the biodegradable yarns are entangled with each other through the barbs of the needles.

[0285] The hydroentangling process may refer to a process of combining the biodegradable yarn webs by spraying high-pressure water jets on one side and absorbing the high-pressure water jets on the other side.

[0286] The stitch bonding process may refer to a process of connecting the biodegradable yarn webs by sewing threads and needles.

[0287] The calendering process may refer to a process of pressing the biodegradable yarn webs and then thermally curing them.

[0288] The air-through bonding process may refer to a process of bonding the biodegradable yarn webs by high-temperature hot air.

[0289] The biodegradable nonwoven fabric according to the present invention can be manufactured by these processes.

[0290] The biodegradable nonwoven fabric is lightweight and has excellent strength, a high surface area, and porosity, so it can be applied to products that require moisture absorption.

[0291] The biodegradable nonwoven fabric may include yarns having an average diameter of 1 μm to 500 μm, 1 μm to 400 μm, 1 μm to 300 μm, 1 μm to 200 μm, or 10 μm to 100 μm.

[0292] The biodegradable nonwoven fabric can be treated. The biodegradable nonwoven fabric can be treated with an antistatic agent to prevent static electricity. The biodegradable nonwoven fabric can be waterproofed with a hydrophobic material. The biodegradable nonwoven fabric can be antibacterial-treated with an antibacterial material.

[0293] The biodegradable nonwoven fabric can be embossed. The biodegradable nonwoven fabric can be printed. The biodegradable nonwoven fabric can be embossed or printed to a thickness and size suitable for the article to which it is applied.

[0294] The biodegradable resin composition can be manufactured into an injection-molded article by an injection molding process.

[0295] The biodegradable resin composition can be a granulated biodegradable resin composition.

[0296] The granulated biodegradable resin composition can be made into an injection-molded article using an injection molding machine at an injection molding barrel temperature of 150°C to 250°C, 160°C to 250°C, 160°C to 240°C, or 160°C to 230°C.

[0297] The injection molding process can be carried out by injection molding methods such as injection compression molding, injection stamping molding, gas-assisted injection molding, foam molding, insert molding, in-mold coating molding, insulated mold molding, rapid heating and cooling mold molding, two-color molding, sandwich molding, or ultra-high-speed injection molding.

[0298] The biodegradable resin composition also has excellent injectability, so during the injection process, the demolding performance is excellent and it can maintain the shape of the injection-molded article.

[0299] The biodegradable resin composition can be made into a foam-molded article through a foaming process.

[0300] The biodegradable resin composition can include a foaming agent.

[0301] The foaming agent can undergo a phase change from solid to gas or from liquid to gas by mixing with the molten biodegradable resin composition or injecting it under pressure, or it can be a gas itself, and can be used to control the foaming ratio (foaming density) of the foamed sheet.

[0302] The foaming agent can include at least one selected from the group consisting of aliphatic hydrocarbons, alicyclic hydrocarbons, halogenated hydrocarbons, inorganic gases, and water.

[0303] The biodegradable resin composition has excellent foaming properties, so when made into a molded article, the foaming ratio can be increased, and uniform cell sizes of the foam and a uniform thickness of the molded article can be achieved.

[0304] The biodegradable nonwoven fabric according to the present invention includes a biodegradable resin composition. The biodegradable resin composition includes a first biodegradable resin. The first biodegradable resin can be the same as the above-mentioned first biodegradable resin.

[0305] The biodegradable resin composition can also include a second biodegradable resin. The second biodegradable resin can be the same as the above-mentioned second biodegradable resin.

[0306] Based on the total weight of the biodegradable resin composition, a second biodegradable resin may be included in the following content: less than 95%, 90% or less, 85% or less, 80% or less, greater than 0 wt% and 80% or less. When this range is satisfied, the biodegradable nonwoven fabric made from the biodegradable resin composition may have a soft texture, and the mechanical properties can be improved without deteriorating the elasticity.

[0307] The second biodegradable resin may include polylactic acid. The polylactic acid may be the same as the above-mentioned polylactic acid.

[0308] The biodegradable resin composition may include an inorganic filler.

[0309] The inorganic filler may be at least one selected from the group consisting of: calcium sulfate, barium sulfate, talc, talcum powder, bentonite, kaolin, chalk powder, calcium carbonate, graphite, gypsum, conductive carbon black, calcium chloride, iron oxide, alumina, potassium oxide, dolomite, silica, wollastonite, titanium dioxide, silicate, mica, glass fiber, mineral fiber, etc.

[0310] Preferably, the inorganic filler may include titanium dioxide (TiO 2 ). Titanium dioxide may act as a nucleating agent for the first biodegradable resin and / or the second biodegradable resin, thereby improving the crystallization rate. In addition, the adhesion phenomenon of the biodegradable yarn made from the biodegradable resin composition can be suppressed.

[0311] In the particle size distribution of the inorganic filler obtained by the laser diffraction method, the cumulative D 50 may be about 100 μm or less, about 85 μm or less, about 70 μm or less, about 50 μm or less, about 25 μm or less, about 10 μm or less, about 5 μm or less, about 3 μm or less or about 1 μm or less.

[0312] The specific surface area of the inorganic filler may be about 100 m 2 / g or greater. For example, the specific surface area of the inorganic filler may be about 100 m 2 / g or greater, about 105 m 2 / g or greater or about 110 m 2 / g or greater.

[0313] Based on the total weight of the biodegradable resin composition, an inorganic filler may be included in an amount of 0.01 wt% to 5 wt%, 0.01 wt% to 4 wt%, 0.01 wt% to 3 wt%, 0.01 wt% to 2 wt%, 0.05 wt% to 2 wt%, or 0.05 wt% to 1 wt%. When this range is satisfied, the weight increase of the biodegradable nonwoven fabric can be minimized and an appropriate biodegradation rate can be provided.

[0314] The biodegradable resin composition may include an elongation improver.

[0315] As the elongation improver, an oil such as paraffin oil, naphthenic oil, or aromatic oil, or an adipate such as dibutyl adipate, diethylhexyl adipate, dioctyl adipate, or diisopropyl adipate may be used.

[0316] Based on the total weight of the biodegradable resin composition, an elongation improver may be included in an amount of 0.001 wt% to 1 wt%, 0.005 wt% to 1 wt%, 0.01 wt% to 1 wt%, 0.01 wt% to 0.8 wt%, or 0.01 wt% to 0.5 wt%. When this range is satisfied, the elongation of the biodegradable nonwoven fabric can be improved.

[0317] The biodegradable resin composition may include a metal salt.

[0318] Based on the total weight of the biodegradable resin composition, the content of the included metal salt may be about 0.1 ppm to about 1,000 ppm. Based on the total weight of the biodegradable resin composition, the content of the included metal salt may be about 1 ppm to about 500 ppm. Based on the total weight of the biodegradable resin composition, the content of the included metal salt may be about 1 ppm to about 100 ppm. Based on the total weight of the biodegradable resin composition, the content of the included metal salt may be about 1 ppm to about 50 ppm. When this range is satisfied, the biodegradation rate of the biodegradable nonwoven fabric can be appropriately controlled.

[0319] The biodegradable resin composition may include a chain extender.

[0320] The chain extender may include isocyanates. The chain extender may be at least one selected from the group consisting of monofunctional isocyanates and polyfunctional isocyanates. The chain extender may be at least one selected from the group consisting of: toluene 2,4-diisocyanate, toluene 2,6-diisocyanate, diphenylmethane 4,4'-diisocyanate and 2,4'-diisocyanate, naphthalene 1,5-diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, isophorone diisocyanate, and methylenebis(4-isocyanatocyclohexane). The chain extender may include triisocyanates. The chain extender may include tris(4-isocyanatophenyl)methane. The chain extender may be chemically bonded to the first biodegradable resin and / or the second biodegradable resin. The chain extender may be chemically bonded to the polymer contained in the first biodegradable resin and / or the second biodegradable resin. The chain extender may be bonded to the ends of the polymer contained in the first biodegradable resin and / or the second biodegradable resin. In addition, the chain extender may be bonded to the ends of three polymers contained in the first biodegradable resin and / or the second biodegradable resin.

[0321] Based on the total weight of the biodegradable resin composition, the chain extender may be included in an amount of: 0.1 wt% to 10 wt%, 0.1 wt% to 5 wt%, 0.1 wt% to 3 wt%, 0.1 wt% to 1 wt%, or 0.1 wt% to 0.5 wt%. When this range is satisfied, the biodegradable nonwoven fabric may have improved mechanical properties. When this range is satisfied, the biodegradable nonwoven fabric may have suitable biodegradability. The chain extender may react with the terminal carboxyl groups or unreacted carboxyl groups contained in the biodegradable resin composition. Therefore, the biodegradable resin composition may have a low acid value. In addition, the chain extender may couple the polymers contained in the biodegradable resin, thereby increasing the ratio of high molecular weight polymers contained in the biodegradable resin composition. Therefore, the mechanical properties of the biodegradable nonwoven fabric may be improved.

[0322] The biodegradable resin composition may include a heat stabilizer. The heat stabilizer may be the same as the above-mentioned heat stabilizer.

[0323] The biodegradable resin composition may include a reinforcing material.

[0324] The reinforcing material may improve the mechanical properties of the biodegradable resin composition and the biodegradable nonwoven fabric made therefrom. In addition, the reinforcing material may control the deformation characteristics of the biodegradable nonwoven fabric caused by ultraviolet light. In addition, the reinforcing material may control the biodegradability of the biodegradable nonwoven fabric.

[0325] The reinforcing material may be fibers derived from biomass. The reinforcing material may be fibers made of organic materials. The reinforcing material may be nanocellulose.

[0326] The nanocellulose may be one or more selected from the group consisting of: nanocrystalline cellulose, cellulose nanofibers, microfibrillated cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, cellulose acetate, methyl cellulose, ethyl cellulose, propyl cellulose, butyl cellulose, amyl cellulose, hexyl cellulose, and cyclohexyl cellulose.

[0327] The nanocellulose may include ionically bonded metals. The nanocrystalline cellulose may include elemental sodium, sodium carboxylate salts, etc. In addition, the nanocrystalline cellulose may include sulfates. The nanocrystalline cellulose may include sodium cellulose sulfate hydrogen.

[0328] The nanocellulose may be represented by the following formula 2:

[0329] [Formula 2]

[0330] [(C 6 O 5 H 10 ) x SO 3 Na] y

[0331] In formula 2, x may be from 15 to 35, and y may be from 1 to 10. The specific surface area of the nanocellulose may be about 200 m 2 / g to about 600 m 2 / g. The specific surface area of the nanocellulose may be about 300 m 2 / g to about 500 m 2 / g. The weight-average molecular weight of the nanocellulose may be about 10,000 g / mol to about 40,000 g / mol. The weight-average molecular weight of the nanocrystalline cellulose may be about 11,000 g / mol to about 35,000 g / mol.

[0332] The average diameter of the nanocellulose may be about 0.5 nm to about 10 nm. The average diameter of the nanocellulose may be about 1 nm to about 8 nm. The average diameter of the nanocellulose may be about 1.5 nm to about 7 nm.

[0333] The average length of the nanocellulose can be from about 20 nm to about 200 nm. The average length of the nanocellulose can be from about 30 nm to about 180 nm. The average length of the nanocellulose can be from about 35 nm to about 150 nm. When the diameter and length of the nanocellulose satisfy this range, the performance of the biodegradable resin composition and the biodegradable nonwoven fabric obtained using the same can be further improved. The diameter and length of the nanocellulose can be measured by atomic force microscopy in a state of being dispersed in water.

[0334] Based on the entire nanocrystalline cellulose, the content of sulfate in the nanocellulose can be from about 0.6% by weight to about 1.2% by weight. Based on the entire nanocellulose, the content of sulfate in the nanocrystalline cellulose can be from about 0.75% by weight to about 1.1% by weight.

[0335] The pH of the nanocellulose can be 5 to 7. The pH of the nanocellulose can be 6 to 7.

[0336] The ζ potential of the nanocellulose can be from about -25 mV to about -50 mV. The ζ potential of the nanocellulose can be from about -30 mV to about -45 mV.

[0337] Based on 100 parts by weight of the biodegradable resin composition, the content of the included nanocellulose can be from about 0.1 part by weight to about 2 parts by weight. Based on 100 parts by weight of the biodegradable resin composition, the content of the included nanocellulose can be from about 0.3 part by weight to about 1.5 parts by weight. Based on 100 parts by weight of the biodegradable resin composition, the content of the included nanocellulose can be from about 0.5 part by weight to about 1.2 parts by weight. Based on 100 parts by weight of the biodegradable resin composition, the content of the included nanocellulose can be from about 0.6 part by weight to about 1 part by weight.

[0338] Since the nanocellulose has the above characteristics, it can be uniformly dispersed in the biodegradable resin composition. Since the nanocellulose has the above characteristics, the biodegradable nonwoven fabric made from the biodegradable resin composition can have improved mechanical properties. Since the nanocellulose has the above characteristics, the biodegradable nonwoven fabric made from the biodegradable resin composition can have appropriate UV resistance. Since the nanocellulose has the above characteristics, the biodegradable nonwoven fabric made from the biodegradable resin composition can have an appropriate biodegradation rate.

[0339] The biodegradable resin composition can include a plasticizer.

[0340] Plasticizers can impart processability or flexibility to the biodegradable nonwoven fabric to be manufactured. The plasticizer can be glycerol, acrylate, glycerin, glyceryl monostearate (GMS), sorbitol, or a mixture thereof. Based on the total weight of the biodegradable resin composition, the content of the plasticizer can be 0.1 wt% to 2 wt% or less, 0.1 wt% to 1.5 wt% or less, 0.1 wt% to 1.2 wt% or less, or 0.1 wt% to 1 wt% or less. When this range is satisfied, the biodegradable nonwoven fabric made from the biodegradable resin composition can provide flexibility and maintain a certain degree of water resistance during the normal usage period of the user.

[0341] In addition to the first biodegradable resin and the second biodegradable resin, the biodegradable resin composition can include a heterogeneous biodegradable resin.

[0342] The heterogeneous biodegradable resin can be at least one selected from the group consisting of poly(butylene adipate-co-terephthalate) (PBAzT), polyhydroxybutyrate (PHB), poly(butylene succinate) (PBS), poly(butylene sebacate-co-terephthalate) (PBSeT), poly(butylene succinate-co-terephthalate) (PBST), and polyhydroxyalkanoate (PHA).

[0343] Based on 100 parts by weight of the first and second biodegradable resins, the content of the included heterogeneous biodegradable resin can be about 10 parts by weight to about 100 parts by weight. Based on 100 parts by weight of the first and second biodegradable resins, the content of the included heterogeneous biodegradable resin can be about 10 parts by weight to about 60 parts by weight. Based on 100 parts by weight of the first and second biodegradable resins, the content of the included heterogeneous biodegradable resin can be about 20 parts by weight to about 50 parts by weight. When this range is satisfied, the mechanical, optical, and chemical properties of the biodegradable resin can be supplemented, so that the biodegradable nonwoven fabric made from the biodegradable resin composition can have appropriate UV resistance and an appropriate biodegradation rate.

[0344] The biodegradable nonwoven fabric can include the biodegradable resin composition, and the biodegradable resin composition can have a first irreversible strain rate of less than 30% measured by the following Measuring Method 3:

[0345] [Measuring Method 3]

[0346] 1) While the biodegradable resin composition is placed between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet with a thickness of 300 μm;

[0347] 2) The biodegradable resin composition sheet is cut to produce samples, and the samples include test components with a width of 3.18 mm and a length of 25 mm;

[0348] 3) The test component is pulled in the longitudinal direction at a speed of 10 mm / min at room temperature. Here, the test component is pulled 40% more than its total length.

[0349] 4) In a state without external force, the test component is restored at room temperature for 5 minutes;

[0350] 5) The first irreversible strain rate is obtained from the following Equation 1:

[0351] [Equation 1]

[0352] The first irreversible strain rate = (the length of the test segment after restoration - 25 mm) / 25 mm.

[0353] The length of the test component in Equation 1 refers to the length of the test component restored after pulling 40% of the total length of the pulled test component.

[0354] The biodegradable resin composition may have a second irreversible strain rate of less than 20% as measured by the following Measuring Method 4:

[0355] [Measuring Method 4]

[0356] 1) While the biodegradable resin composition is placed between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet with a thickness of 300 μm;

[0357] 2) The biodegradable resin composition sheet is cut to produce samples, and the samples include test components with a width of 3.18 mm and a length of 25 mm;

[0358] 3) The test component is pulled in the longitudinal direction at a speed of 10 mm / min at room temperature. Here, the test component is pulled 30% more than its total length;

[0359] 4) In a state without external force, the test component is restored at room temperature for 5 minutes;

[0360] 5) The second irreversible strain rate is obtained from the following Equation 2:

[0361] [Equation 2]

[0362] Second irreversible strain rate = (Length of the tested segment after recovery - 25 mm) / 25 mm

[0363] The length of the tested component in Equation 2 refers to the length of the tested component after recovery when 30% of the total length of the tested component is pulled.

[0364] The biodegradable resin composition may have a third irreversible strain rate of less than 10% as measured by the following Measuring Method 5:

[0365] [Measuring Method 5]

[0366] 1) While the biodegradable resin composition is placed between a pair of flat stainless - steel molds, compress it at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet with a thickness of 300 μm;

[0367] 2) Cut the biodegradable resin composition sheet to produce a sample that includes a tested component with a width of 3.18 mm and a length of 25 mm;

[0368] 3) Pull the tested component at a speed of 10 mm / min in the longitudinal direction at room temperature, where the tested component is pulled 20% more than its total length;

[0369] 4) Without external force, let the tested component recover at room temperature for 5 minutes;

[0370] 5) The third irreversible strain rate is obtained from the following Equation 3:

[0371] [Equation 3]

[0372] Third irreversible strain rate = (Length of the tested segment after recovery - 25 mm) / 25 mm

[0373] The length of the tested component in Equation 3 refers to the length of the tested component after recovery when 20% of the total length of the tested component is pulled.

[0374] The biodegradable resin composition may have a fourth irreversible strain rate of less than 5% as measured by the following Measuring Method 6:

[0375] [Measuring Method 6]

[0376] 1) While the biodegradable resin composition is placed between a pair of flat stainless - steel molds, compress it at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet with a thickness of 300 μm;

[0377] 2) Cut the biodegradable resin composition sheet to fabricate a sample, which includes a test piece having a width of 3.18 mm and a length of 25 mm;

[0378] 3) Pull the test piece at a speed of 10 mm / min in the longitudinal direction at room temperature, where the test piece is pulled 10% more than its total length;

[0379] 4) Without external force, let the test piece recover at room temperature for 5 minutes;

[0380] 5) The fourth irreversible strain rate is obtained from the following Equation 4:

[0381] [Equation 4]

[0382] Fourth irreversible strain rate = (Length of the recovered test piece - 25 mm) / 25 mm

[0383] The length of the test piece in Equation 4 refers to the length of the test piece recovered after being pulled 10% of its total length.

[0384] The irreversible strain rate can be used as an index representing the elastic recovery and stretchability of the biodegradable nonwoven fabric without external force. In addition, an irreversible strain rate below a specific range can be an index representing that the biodegradable resin composition can be made into ultrafine fibers with a diameter less than 3 μm by the meltblowing process, and thus the manufactured biodegradable nonwoven fabric can have a soft texture. In addition, an irreversible strain rate below a specific range can be an index representing that even if the biodegradable resin composition is made into single fibers with a diameter of 10 μm to 15 μm by the spinning process, the manufactured biodegradable nonwoven fabric can have a soft texture. In addition, an irreversible strain rate below a specific range can be an index representing that the manufactured biodegradable nonwoven fabric exhibits a soft texture, and at the same time, within the temperature range of about 15°C to 40°C commonly used, the nonwoven fabric can exhibit elasticity.

[0385] Specifically, reference can be made to Figure 2 and Figure 3 to obtain the irreversible strain rate. Figure 2 Schematically illustrates the process for manufacturing a biodegradable resin composition sheet according to an embodiment. Figure 3 Schematically illustrates the method for measuring the irreversible strain rate of a test piece according to an embodiment.

[0386] Refer to Figure 2 and Figure 3, The biodegradable resin composition can be placed between a pair of flat stainless steel molds 100 and 200. Next, a pressure of 20 Mpa can be applied to the pair of flat stainless steel molds 100 and 200 at 200 °C. Under the action of the pressure, the biodegradable resin composition is compressed, thereby manufacturing a biodegradable resin composition sheet 300 with a thickness of 300 μm.

[0387] The biodegradable resin composition sheet 300 can be manufactured into a sample 400, which includes a test component 500 with a width of 3.18 mm and a length of 25 mm according to ASTM318 standard.

[0388] At room temperature, the relative end 600 of the sample 400 except the test component 500 can be pulled longitudinally at a speed of 10 mm / min by a fixing element (not shown), so as to pull 40%, 30%, 20% or 10% more than the total length (L) of the test component 500.

[0389] Then, at room temperature, the test component 500 is restored for 5 minutes in a state without external force, and then the strain rate of the total length (L) of the test component 500 in the irreversible state is obtained according to Equations 1 to 4.

[0390] The biodegradable nonwoven fabric includes a biodegradable resin composition, and through dynamic mechanical analysis, the biodegradable resin composition has a temperature of the maximum loss tangent angle from -40 °C to 0 °C. In the biodegradable nonwoven fabric, the lowest temperature of the rubbery plateau region is lower than 30 °C, the rubbery plateau region is higher than the temperature of the maximum loss tangent angle, and the rate of change of the loss tangent angle is at a temperature less than 0.025 / 10 °C.

[0391] In particular, the maximum loss tangent angle temperature and the lowest temperature of the rubbery plateau region can be obtained through dynamic mechanical analysis under the following conditions:

[0392] - Measuring device: Dynamic Mechanical Analyzer (DMA) TA 2980 / Q800

[0393] - Heating temperature: -40 °C to 80 °C

[0394] - Heating rate: 10 °C / min

[0395] The loss tangent angle (tanδ) can be calculated by the equation expressed as tanδ = (G") / (G') after measuring the storage modulus (G') and the loss modulus (G") at a measurement frequency of 1 Hz through dynamic mechanical analysis.

[0396] The temperature of the maximum loss tangent angle can refer to the peak temperature determined by the spectrum of the loss tangent angle in the heating temperature range of -40 °C to 80 °C of the dynamic mechanical analysis.

[0397] The rubbery plateau region is defined by the plateau modulus and can refer to a region where the storage modulus and the loss modulus are almost constant after rapidly decreasing in the glass transition region, and in particular can refer to a temperature range where the rate of change of the loss tangent is less than 0.025 / 10 °C. The lowest temperature of the rubbery plateau region can refer to the lowest temperature value within the temperature range of the rubbery plateau region.

[0398] The temperature range of the maximum loss tangent and the minimum temperature range of the rubbery plateau region can be an index indicating that the nonwoven fabric can have elastic recovery within the temperature range of use, such that the nonwoven fabric can be stretched by an external force but does not break and can return to its original length.

[0399] For the biodegradable resin composition, the temperature of the maximum loss tangent according to dynamic mechanical analysis is from -40 °C to 0 °C, the lowest temperature of its rubbery plateau region is below 30 °C, the rubbery plateau region is higher than the temperature of the maximum loss tangent angle, and the rate of change of the loss tangent angle is in a temperature range less than 0.025 / 10 °C.

[0400] In addition, as measured according to the following Measuring Method 7, the biodegradable resin composition has a temperature of the maximum loss tangent from -40 °C to 0 °C, and the lowest temperature of the rubbery plateau region is below 30 °C:

[0401] [Measuring Method 7]

[0402] 1) While placing the biodegradable resin composition between a pair of flat stainless steel molds, it is compressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm;

[0403] 2) The biodegradable resin composition sheet is cut to produce a sample, and the sample includes a test part having a width of 5 mm and a length of 12 mm;

[0404] 3) By dynamic mechanical analysis, the loss tangent of the test part is measured at the temperature during the temperature rise from -40 °C to 80 °C;

[0405] 4) The temperature having the maximum value of the loss tangent is the temperature of the maximum loss tangent;

[0406] 5) The temperature range where the rate of change of the loss tangent is in a temperature range less than 0.025 / 10 °C is the rubbery plateau region.

[0407] In the biodegradable resin composition, the maximum loss tangent temperature measured by measuring method 5 can be from -40°C to -5°C, and the lowest temperature of the rubbery plateau region can be lower than 28°C. In the biodegradable resin composition, the maximum loss tangent temperature measured by measuring method 5 can be from -40°C to -10°C, and the lowest temperature of the rubbery plateau region can be lower than 26°C. In the biodegradable resin composition, the maximum loss tangent temperature measured by measuring method 5 can be from -40°C to -15°C, and the lowest temperature of the rubbery plateau region can be 15°C or higher and 25°C or lower. When this range is satisfied, the biodegradable nonwoven fabric made from the biodegradable resin composition can exhibit excellent elasticity and have a soft texture.

[0408] The crystallization temperature of the biodegradable resin composition can be 20°C to 130°C, 30°C to 130°C, 30°C to 100°C, 30°C to 90°C, 30°C to 80°C, or 30°C to 70°C. When the biodegradable resin composition has a crystallization temperature within this range, the biodegradable resin composition can be extruded and rapidly crystallized when manufacturing the biodegradable nonwoven fabric. Therefore, breakage of the manufactured biodegradable yarn can be prevented, and entanglement of the biodegradable yarn can be suppressed due to an appropriate crystallization rate. Therefore, the biodegradable resin composition having this crystallization temperature can be an index indicating that the tensile strength and elongation can be improved.

[0409] The crystallization temperature can be measured according to ASTM D3417. In particular, the crystallization temperature can be measured as follows: using differential scanning calorimetry (DSC), heating from 40°C to 200°C at a rate of 10°C / min, then performing a first heat history removal process of isothermal heating for 5 minutes, and then performing a second cooling process of cooling from 200°C to -50°C at a rate of 10°C / min and isothermal heating for 5 minutes.

[0410] The biodegradable resin composition can have a melt index.

[0411] According to ASTM D1238, after pressing the biodegradable resin composition with a weight of about 2.16 kg at about 190°C, the discharge amount in 10 minutes can be 5 g / 10 min to 50 g / 10 min, 10 g / 10 min to 50 g / 10 min, 15 g / 10 min to 50 g / 10 min, 20 g / 10 min to 50 g / 10 min, or 22 g / 10 min to 50 g / 10 min.

[0412] According to ASTM D1238, after pressing the biodegradable resin composition at about 230 °C using a weight of about 2.16 kg, the discharge amount in 10 minutes can be 50 g / 10 min to 130 g / 10 min, 55 g / 10 min to 130 g / 10 min, 60 g / 10 min to 130 g / 10 min, 60 g / 10 min to 125 g / 10 min, or 60 g / 10 min to 120 g / 10 min.

[0413] According to ASTM D1238, after pressing the biodegradable resin composition at about 250 °C using a weight of about 2.16 kg, the discharge amount in 10 minutes can be 100 g / 10 min to 200 g / 10 min, 100 g / 10 min to 190 g / 10 min, 100 g / 10 min to 180 g / 10 min, 110 g / 10 min to 180 g / 10 min, or 110 g / 10 min to 170 g / 10 min.

[0414] When this range is satisfied, the discharge amount of the biodegradable resin composition during the spinning process is uniform, so that it can have excellent spinning ability, the yarns formed by the biodegradable nonwoven fabric made of the biodegradable resin composition will not break, and it shows improved tensile strength and elongation.

[0415] The biodegradable resin composition can be made into a biodegradable nonwoven fabric by a dry-laying method, a wet-laying method or a direct-spinning and laying method.

[0416] The dry-laying method can be a carding process, in which a single-fiber raw material layer made of the biodegradable resin composition is laminated on a collector by a device including a plurality of gears; or it can be an air-laying process, in which a single-fiber raw material made of the biodegradable resin composition is arranged on a collector by a device moved by an air flow.

[0417] The wet-laying method can be a water suspension process, in which a single-fiber raw material made of the biodegradable resin composition is dispersed in water, transferred to a wire mesh or a perforated drum, and then the residual moisture is sucked away, pressed and dried.

[0418] The direct-spinning and laying method can be a spunbond process, in which a long-fiber raw material made of the biodegradable resin composition forms a Venturi net on a collector; a meltblown process, in which the biodegradable resin composition is made into ultrafine fibers by high-temperature air; or an electrospinning process, in which the biodegradable resin composition is made into ultrafine fibers by electrospinning.

[0419] The biodegradable resin composition according to the present invention can be made into a biodegradable nonwoven fabric not only by a dry-laid method or a wet-laid method, but also by a direct spinning and laying process, so that the biodegradable nonwoven fabric can include ultrafine fibers, thereby showing a soft texture.

[0420] After the dry-laid method, the wet-laid method or the direct spinning and laying process, the biodegradable resin composition can be subjected to at least one of a needling process, a hydroentangling process, a stitch-bonding process, calendering and air-through bonding.

[0421] Through these processes, the binding force between the yarns of the biodegradable nonwoven fabric can be enhanced, the tensile strength and elongation can be improved, and the biodegradable nonwoven fabric can be prevented from fuzzing.

[0422] The needling process can refer to a process in which needles penetrate a biodegradable yarn web so that the biodegradable yarns are entangled with each other through the barbs of the needles.

[0423] The hydroentangling process can refer to a process of combining a biodegradable yarn web by spraying high-pressure water flow on one side and absorbing the high-pressure water flow on the other side.

[0424] The stitch-bonding process can refer to a process of connecting a biodegradable yarn web by sewing threads and needles.

[0425] The calendering process can refer to a process of pressing a biodegradable yarn web and then thermally fusing it.

[0426] The air-through bonding process can refer to a process of bonding a biodegradable yarn web with high-temperature hot air.

[0427] The biodegradable nonwoven fabric can be treated. The biodegradable nonwoven fabric can be treated with an antistatic agent to prevent static electricity. The biodegradable nonwoven fabric can be waterproofed with a hydrophobic material. The biodegradable nonwoven fabric can be antibacterial-treated with an antibacterial agent.

[0428] The biodegradable nonwoven fabric can be embossed. The biodegradable nonwoven fabric can be printed. The biodegradable nonwoven fabric can be embossed or printed to have a thickness and size suitable for the article to which it is applied.

[0429] Hereinafter, the present invention will be described in more detail based on the following examples and comparative examples. However, the examples and comparative examples are only provided as examples for more detailed explanation of the present invention, and the present invention is not limited to the following examples and comparative examples.

[0430] First Preparation Example

[0431] Preparation Example 1-1 - Preparation of Nano-Cellulose Crystallization Promoter

[0432] Cellulose nanocrystals in the form of a dry powder having a particle size of about 1 μm to about 50 μm (NVC-100, manufacturer: Celluforce) were dispersed in water at 1 wt%, and then sonicated for 2 minutes using a tip-type sonicator at an output of 20,000 J / s to prepare a nanocellulose crystallization promoter.

[0433] Preparation Example 1-2 - Preparation of Titanium Dioxide Crystallization Promoter

[0434] Titanium dioxide (TiO 2 ) having a particle size of about 0.2 μm and anatase phase was dispersed in 1,4-butanediol (1,4-BDO) at 5 wt% to produce a slurry. Then, the slurry was stirred at a speed of 1,000 rpm for 2 hours and then filtered through a 500-mesh filter to prepare a titanium dioxide crystallization promoter.

[0435] First Example - Preparation of Biodegradable Resin Composition

[0436] Example 1-1

[0437] - First step: Obtain a prepolymer

[0438] 1,4-Butanediol (1,4-BDO) and terephthalic acid (TPA) were fed into a 5 kg esterification reactor equipped with a nitrogen inlet and a stirrer to prepare a slurry. Here, the molar ratio of 1,4-butanediol (1,4-BDO) to terephthalic acid (TPA) was 1.4:1, and the D 50 of terephthalic acid (TPA) was 130 μm.

[0439] The slurry was fed into the reactor through a feed line, and tetrabutyl titanate (Dupont, produced by Tyzor TnBT) at 250 ppm was fed therein as a titanium-based catalyst. Then, the slurry was heated to 210 °C and the esterification reaction was carried out until about 90% or more of the by-product water was discharged to prepare a first prepolymer.

[0440] To the first esterification reaction product, 53 mol% of 1,4-butanediol (1,4-BDO) based on the total moles of the diol component was added, 53 mol% of adipic acid (AA) based on the total moles of the dicarboxylic acid component was added, and 200 ppm of a titanium-based catalyst tetrabutyl titanate (Dupont, produced by Tyzor TnBT) based on the total weight of the diol component and the dicarboxylic acid component was added. In addition, 100 ppm of the nanocellulose crystallization promoter according to Preparation Example 1 was added to the first esterification reaction product. Next, the second esterification reaction was carried out at 220 °C and atmospheric pressure for about 2 hours and 30 minutes until 95% of the by-product water was discharged, thereby preparing a second prepolymer having a number-average molecular weight of 5,500 g / mol.

[0441] - Step 2: Polycondensation reaction

[0442] The second prepolymer was transferred to a 5 kg-sized polycondensation reactor. 150 ppm of a titanium-based catalyst tetrabutyl titanate (Dupont, manufactured by Tyzor TnBT) and 500 ppm of a triethyl phosphate stabilizer based on the total weight of the second prepolymer were added, and then it was stabilized for about 10 minutes.

[0443] Then, after heating to 240 °C, the polycondensation reaction was carried out at 0.5 Torr for 2 hours, thereby preparing a biodegradable resin composition.

[0444] Example 1-2

[0445] A biodegradable resin composition was prepared in the same manner as the preparation process of Example 1-1, except that 500 ppm of the nanocellulose crystallization promoter according to Preparation Example 1-1 was added instead of 100 ppm of the nanocellulose crystallization promoter according to Preparation Example 1-1 added to the first esterification reaction product in Example 1-1.

[0446] Example 1-3

[0447] A biodegradable resin composition was prepared in the same manner as the preparation process of Example 1-1, except that 200 ppm of the nanocellulose crystallization promoter according to Preparation Example 1-1 and 3,000 ppm of the titanium dioxide crystallization promoter according to Preparation Example 2 were added instead of 100 ppm of the nanocellulose crystallization promoter according to Preparation Example 1-1 added to the first esterification reaction product in Example 1-1, and 1,000 ppm of an external lubricant calcium stearate was added in the polycondensation reaction.

[0448] Example 1-4

[0449] The biodegradable resin composition according to Example 1-1, 500 ppm of the titanium dioxide crystal growth promoter according to Preparation Example 1-2, and 2,000 ppm of the external lubricant calcium stearate were fed into an extrusion molding machine (Toyo Seiki Seisaku-sho, Ltd.) equipped with a twin screw and a T-die extrusion molding device ( L / D = 25), and kneaded at about 140 °C to prepare a biodegradable resin composition.

[0450] Example 1-5

[0451] A biodegradable resin composition was prepared in the same manner as in the preparation process of Example 1-4, except that 6,000 ppm of the titanium dioxide crystal growth promoter according to Preparation Example 1-2 and 500 ppm of the external lubricant calcium stearate were added, instead of 500 ppm of the titanium dioxide crystal growth promoter according to Preparation Example 1-2 and 2,000 ppm of the external lubricant calcium stearate as in Example 1-4.

[0452] Example 1-6

[0453] A composition containing the biodegradable resin composition according to Example 1-1 and PLA (L130, Corbion Total) in a weight ratio of 8:2, 500 ppm of the titanium dioxide crystal growth promoter according to Preparation Example 1-2, and 2,000 ppm of the external lubricant calcium stearate was fed into an extrusion molding machine (Toyo Seiki Seisaku-sho, Ltd.) equipped with a twin screw and a T-die extrusion molding device ( L / D = 25), and kneaded at about 140 °C to prepare a biodegradable resin composition.

[0454] Comparative Example 1-1

[0455] A biodegradable resin composition was prepared in the same manner as in the preparation process of Example 1-1, except that the nanocellulose crystal growth promoter according to Preparation Example 1-1 was not added to the first esterification product.

[0456] Comparative Example 1-2

[0457] The biodegradable resin composition according to Example 1-1 and 8,000 ppm of the nanocellulose crystal growth promoter according to Preparation Example 1-1 were fed into an extrusion molding machine (Toyo Seiki Seisaku-sho, Ltd.) equipped with a twin screw and a T-die extrusion molding device ( L / D = 25), and kneaded at about 140 °C to prepare a biodegradable resin composition.

[0458] Comparative Examples 1-3

[0459] The biodegradable resin composition according to Example 1-1 and 63,000 ppm of the titanium dioxide crystallization promoter according to Preparation Example 1-2 were fed into an extrusion molding machine equipped with a twin screw (Toyo Seiki Seisaku-sho, Ltd.) T-die extrusion molding apparatus ( L / D = 25), and kneaded at about 140 °C to prepare a biodegradable resin composition.

[0460] Comparative Example 1-4

[0461] A composition containing the biodegradable resin composition according to Example 1-1 and PLA (L130, Corbion Total) in a weight ratio of 8:2, 63,000 ppm of the titanium dioxide crystallization promoter according to Preparation Example 1-2, and 2,000 ppm of the external lubricant calcium stearate was fed into an extrusion molding machine equipped with a twin screw (Toyo Seiki Seisaku-sho, Ltd.) T-die extrusion molding apparatus ( L / D = 25), and kneaded at about 140 °C to prepare a biodegradable resin composition.

[0462] First Experimental Example

[0463] Experimental Example 1-1 - Isothermal Crystallization Time

[0464] The biodegradable resin compositions of each of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 were heated at a heating rate of 10 °C / min until 220 °C, and then held for 5 minutes. Subsequently, the temperature was lowered to 70 °C at a cooling rate of 100 °C / min, and then held in an isothermal state for 100 minutes.

[0465] Subsequently, using differential scanning calorimetry, the time when the total area of the crystallization peak of the biodegradable resin composition was halved was measured. The results are shown in Table 1 below.

[0466] Experimental Example 1-2 - Glass Transition Temperature, Crystallization Temperature, Melting Temperature

[0467] According to Experimental Example 1-1, using differential scanning calorimetry, the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm) of the biodegradable resin compositions of each of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 were measured. The results are shown in Table 1 below.

[0468] Experimental Example 1-3 - Melt Flow Rate

[0469] According to ASTM D1238, the biodegradable resin compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 were pressed at 190 °C using a 2.16 kg weight, and then the discharge amount for 10 minutes was measured. The results are shown in Table 1 below.

[0470] Experimental Example 1-4 - Tensile Strength, Elongation at Break

[0471] The biodegradable resin compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 were made into specimens with a thickness of 300 μm according to KSM6518. Then, according to ASTM D638, using a universal testing machine (UTM, model: 4206-001) produced by INSTRON Corporation, the tensile strength (kgf / mm 2 = 9.8 MPa) and elongation at break of the specimens were measured at a rate of 100 mm / min. The results are shown in Table 1 below.

[0472] Experimental Example 1-5 - Evaluation of Spinning Ability

[0473] Using a melt spinning (filament) device, under conditions such as a spinning speed of 24 g / min, a melting temperature of 210 °C, a winder draw ratio of 2.2, and a quench air temperature of 10 °C, the spinning ability of the biodegradable resin compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 was evaluated according to the following criteria. The results are shown in Table 1 below.

[0474] - ◎: The nozzle spinning is smooth, and no fiber breakage or coalescence occurs.

[0475] - △: The nozzle spinning is smooth, but fiber breakage or coalescence occurs

[0476] - ×: The nozzle is clogged, so spinning cannot be performed.

[0477] Experimental Example 1-6 - Evaluation of Injection Moldability

[0478] The biodegradable resin compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 were held in a mold at 200 °C for 5 minutes, and then their injection moldability was evaluated according to the following criteria. The results are shown in Table 1 below.

[0479] - ◎: The demolding property is excellent, and the shape of the injection molded product is maintained.

[0480] - △: No residue appears in the mold, but flow marks appear on the injection molded product.

[0481] - ×: Residue appears in the mold, or carbon marks appear on the injection molded product.

[0482] Experimental Example 1-7 - Foaming Evaluation

[0483] A mixture of the biodegradable resin compositions of each of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4, which were mixed at a weight ratio of 3:7, and PLA (4032D, Nature Works) was fed into a gas foaming apparatus, and then its foaming property was evaluated according to the following criteria. The results are shown in Table 1 below.

[0484] - ◎: The maximum foaming ratio is 5 times or higher.

[0485] - ○: The maximum foaming ratio is 3 times or higher and less than 5 times.

[0486] - △: The maximum foaming ratio is 1 time or higher and less than 3 times.

[0487] - ×: No foaming

[0488] Experimental Example 1-8 - Biodegradability

[0489] For the biodegradable resin compositions of each of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4, the aerobic biodegradability was measured for 6 months under composting conditions according to ISO 14855. The results are shown in Table 1 below.

[0490] [Table 1]

[0491]

[0492]

[0493] As shown in Table 1, it was confirmed that the biodegradable resin compositions of Examples 1-1 to 1-6 exhibited biodegradability equal to or superior to that of the biodegradable resin compositions of Comparative Examples 1-1 to 1-4.

[0494] Furthermore, it was confirmed that since the biodegradable resin compositions of Examples 1-1 to 1-6 contained a crystal growth promoter in an amount of 100 ppm to 50,000 ppm and satisfied the isothermal crystallization time at 90 °C of 10 seconds to 900 seconds, the spinning ability, injection moldability, foaming property, and mechanical properties were all excellent.

[0495] Second Preparation Example

[0496] Preparation of Pretreated Nanocellulose

[0497] Cellulose nanocrystals in the form of a dry powder with a particle size of about 1 μm to about 50 μm (NVC-100, manufacturer: Celluforce) were dispersed in water at 1% by weight, and then sonicated for 1 minute using a tip-type sonicator at an output of 20,000 J / s to produce pretreated nanocellulose.

[0498] Preparation of PBAT resin

[0499] Preparation of PBAT resin #1

[0500] - First step: Pretreatment to obtain a slurry

[0501] In the absence of a catalyst, the nanocellulose pretreated according to the preparation example, 1,4-butanediol (1,4-BDO), and terephthalic acid (TPA) were mixed and fed into a slurry tank (the bottom of the slurry tank was anchor-shaped, the height from the stirrer was 40 mm, and three rotating blades were provided). Here, the molar ratio of 1,4-butanediol (1,4-BDO) to terephthalic acid (TPA) was 1.4:1, and the D 50 of terephthalic acid (TPA) was 130 μm. The mixture fed into the slurry tank was stirred at 60 °C and 100 rpm for 1 hour to obtain a slurry without phase separation.

[0502] - Second step: Obtain a prepolymer

[0503] The slurry obtained in the first step was fed into a reactor through a supply line. Tetrabutyl titanate (Dupont, manufactured by Tyzor TnBT), a titanium-based catalyst at 250 ppm based on the total weight of the slurry, was fed into the reactor, and then the first esterification was carried out at 220 °C under atmospheric pressure for about 1 hour and 30 minutes until 95% of the by-product water was discharged.

[0504] To the first esterification reaction product, 53 mol% of 1,4-butanediol (1,4-BDO) based on the total molar amount of the diol component, 53 mol% of adipic acid (AA) based on the total molar amount of the dicarboxylic acid component, and 200 ppm of tetrabutyl titanate (Dupont, manufactured by Tyzor TnBT), a titanium-based catalyst, were added. Next, the second esterification reaction was carried out at 220 °C and atmospheric pressure for about 2 hours and 30 minutes until 95% of the by-product water was discharged, thereby producing a prepolymer with a number average molecular weight of 5,500 g / mol.

[0505] - Third step: Carry out a polycondensation reaction

[0506] Based on the total weight of the prepolymer produced in the second step, 150 ppm of the titanium-based catalyst tetrabutyl titanate (Dupont, manufactured by Tyzor TnBT) and 500 ppm of the triethyl phosphate stabilizer were added, and then it was stabilized for about 10 minutes. Next, after raising the temperature to 240 °C, a polycondensation reaction was carried out at 0.5 torr for 2 hours, thereby producing a polymer with a number average molecular weight of 34,000 g / mol. Next, the polymer was cooled to 5 °C and cut with a pelletizer to obtain PBAT resin #1 pellets.

[0507] Production of PBAT Resins #2 to #5

[0508] PBAT resin pellets #2 to #5 were manufactured in the same manner as the production method of PBAT resin #1, except that the components and contents shown in Table 2 below and the temperatures and times of the first and second esterification reactions and the polycondensation reaction shown in Table 3 below were used.

[0509] [Table 2]

[0510]

[0511] [Table 3]

[0512]

[0513] Preparation of Biodegradable Resin Composition

[0514] Preparation of Biodegradable Resin Composition #1

[0515] A raw material composition was prepared using the components and contents shown in Table 4 below. Next, the raw material composition was fed into a T-die extrusion molding device (20 mm, L / D = 25, manufactured by Toyo Seiki Seisaku-sho, Ltd.) equipped with a twin-screw as an extrusion molding machine and kneaded at 160 °C to produce pelletized biodegradable resin composition #1.

[0516] Preparation of Biodegradable Resin Compositions #2 to #9

[0517] Biodegradable resin compositions #2 to #9 were prepared in the same manner as the preparation method of biodegradable resin composition #1, except that the components and contents shown in Table 4 below were used.

[0518] [Table 4]

[0519]

[0520] Second Example

[0521] Example 2-1

[0522] The biodegradable resin composition #1 was supplied into the die of the meltblowing manufacturing apparatus. The die temperature was set at 230 °C. Using a meltblowing nozzle ( Distance between each nozzle hole: 0.20 mm), the biodegradable resin composition #1 was discharged together with high-temperature and high-speed air (250 °C, air volume: 600 m 3 / hr) blown from both sides of the nozzle, and the discharge amount was 0.52 g / min per single hole of each nozzle. Then, cooling and dispersion treatment was performed with cooling air (15 °C, air flow rate: 6,000 m 3 / hr), and then the meltblown nonwoven fabric was blown onto the carrier film so that the weight of the meltblown nonwoven fabric was 70 g / m when the distance from the spinneret surface to the collector (DCD) was 120 mm 2 , thereby manufacturing a meltblown nonwoven fabric.

[0523] Example 2-2

[0524] A meltblown nonwoven fabric was manufactured in the same manner as in Example 2-1, except that the biodegradable resin composition #2 was used instead of the biodegradable resin composition #1 in Example 2-1.

[0525] Example 2-3

[0526] A meltblown nonwoven fabric was manufactured in the same manner as in Example 2-1, except that the biodegradable resin composition #3 was used instead of the biodegradable resin composition #1 in Example 2-1.

[0527] Example 2-4

[0528] A meltblown nonwoven fabric was manufactured in the same manner as in Example 2-1, except that the biodegradable resin composition #4 was used instead of the biodegradable resin composition #1 in Example 2-1.

[0529] Example 2-5

[0530] A meltblown nonwoven fabric was manufactured in the same manner as in Example 2-1, except that the biodegradable resin composition #5 was used instead of the biodegradable resin composition #1 in Example 2-1.

[0531] Example 2-6

[0532] A meltblown nonwoven fabric was manufactured in the same manner as in Example 2-1, except that the biodegradable resin composition #6 was used instead of the biodegradable resin composition #1 in Example 2-1.

[0533] Comparative Example 2-1

[0534] A meltblown nonwoven fabric was produced in the same manner as in Example 2-1, except that the biodegradable resin composition #7 was used instead of the biodegradable resin composition #1 of Example 2-1.

[0535] Comparative Example 2-2

[0536] A meltblown nonwoven fabric was produced in the same manner as in Example 2-1, except that the biodegradable resin composition #8 was used instead of the biodegradable resin composition #1 of Example 2-1.

[0537] Comparative Example 2-3

[0538] A meltblown nonwoven fabric was produced in the same manner as in Example 2-1, except that the biodegradable resin composition #9 was used instead of the biodegradable resin composition #1 of Example 2-1.

[0539] Comparative Example 2-4

[0540] A meltblown nonwoven fabric was produced in the same manner as in Example 2-1, except that the biodegradable resin composition #10 was used instead of the biodegradable resin composition #1 of Example 2-1.

[0541] Second Experimental Example

[0542] Experimental Example 2-1 - Irreversible Strain Rate

[0543] Each of the biodegradable resin compositions #1 to #10 was placed between a pair of flat stainless steel molds and pressed at 200 °C under a pressure of 20 MPa to produce a biodegradable resin composition sheet having a thickness of 300 μm.

[0544] Next, the biodegradable resin composition sheet was cut to produce a sample that included a test piece having a width of 3.18 mm and a length of 25 mm.

[0545] Next, the test piece was pulled in the longitudinal direction at a rate of 10 mm / min at room temperature. Here, the test piece was pulled 40%, 30%, 20%, or 10% more than its total length.

[0546] Next, the test piece was allowed to recover at room temperature for 5 minutes without an external force, and then the first to fourth irreversible strain rates were obtained using a universal testing machine (UTM, model: 4206-001) manufactured by INSTRON Corporation according to the following Equations 1 to 4. The results are shown in Table 5 below:

[0547] [Equation 1]

[0548] The first irreversible strain rate = (the length of the tested segment after recovery - 25 mm) / 25 mm.

[0549] The length of the tested component in Equation 1 refers to the length of the tested component after recovery when 40% of the total length of the tested component is pulled.

[0550] [Equation 2]

[0551] The second irreversible strain rate = (the length of the tested segment after recovery - 25 mm) / 25 mm

[0552] The length of the tested component in Equation 2 refers to the length of the tested component after recovery when 30% of the total length of the tested component is pulled.

[0553] [Equation 3]

[0554] The third irreversible strain rate = (the length of the tested segment after recovery - 25 mm) / 25 mm

[0555] The length of the tested component in Equation 3 refers to the length of the tested component after recovery when 20% of the total length of the tested component is pulled.

[0556] [Equation 4]

[0557] The fourth irreversible strain rate = (the length of the tested segment after recovery - 25 mm) / 25 mm

[0558] The length of the tested component in Equation 4 refers to the length of the tested component after recovery when 10% of the total length of the tested component is pulled.

[0559] Experimental Example 2-2 - Dynamic Mechanical Analysis

[0560] Each of the biodegradable resin compositions #1 to #10 was placed between a pair of flat stainless steel molds and pressed at 200 °C under a pressure of 20 Mpa to produce a biodegradable resin composition sheet having a thickness of 300 μm.

[0561] Next, the biodegradable resin composition sheet was cut to produce a sample that included a tested component having a width of 5 mm and a length of 12 mm.

[0562] Next, for the tested component, the maximum loss tangent temperature and the lowest temperature of the rubbery plateau region were obtained by dynamic mechanical analysis under the following conditions. The rubbery plateau region is above the maximum loss tangent temperature, and the loss tangent change rate was obtained in a temperature range less than 0.025 / 10 °C. The results are shown in Table 5 below:

[0563] - Measuring device: Dynamic Mechanical Analyzer (DMA) TA 2980 / Q800

[0564] - Heating temperature: -40°C to 80°C

[0565] - Heating rate: 10°C / min

[0566] Experimental Example 2-3 - Crystallization Temperature

[0567] The crystallization temperature and melting temperature of each of the biodegradable resin compositions #1 to #10 were measured according to ASTM D3417. Specifically, a first thermal history removal process was carried out by heating from 40°C to 220°C at a rate of 10°C / min and holding isothermally for 5 minutes using differential scanning calorimetry (DSC), and a second cooling process was carried out by cooling from 200°C to -50°C at a rate of 10°C / min and holding isothermally for 5 minutes. Again, a process of heating from -50°C to 220°C at a rate of 10°C / min was carried out. Through these processes, the crystallization temperature and melting temperature were determined. The results are shown in Table 5 below.

[0568] Experimental Example 2-4 - Melt Index

[0569] According to ASTM D1238, each of the biodegradable resin compositions #1 to #10 was pressed using a 2.16 kg weight at temperature conditions of 190°C, 230°C, and 250°C, and then the discharge amount for 10 minutes was measured. The results are shown in Table 5 below.

[0570] Experimental Example 2-5 - Biodegradability

[0571] For each nonwoven fabric manufactured in Examples 2-1 to 2-6 and Comparative Examples 2-1 to 2-4, the amount of carbon dioxide generated was measured according to KSM3100-1 to evaluate biodegradability. Specifically, an inoculation container containing only compost manufactured in a composting plant was prepared, and a test container was prepared in which a nonwoven fabric in an amount of 5 wt% of the dry weight of the compost was fed into the compost. Next, cultivation was carried out for 180 days under conditions of a temperature of about 58 ± 2°C, a moisture content of 50%, and an oxygen concentration of 6% or higher, and the carbon dioxide generated from each test container was captured and titrated with an aqueous phenolphthalein solution to measure the amount of carbon dioxide generated from each test container. The biodegradability was calculated using the following calculation formula 1 based on the measured carbon dioxide generation amount. The results are shown in Table 5 below:

[0572] [Calculation Formula 1]

[0573]

[0574] Experimental Example 2-6 - Texture

[0575] The texture of each nonwoven fabric produced in Examples 2-1 to 2-6 and Comparative Examples 2-1 to 2-4 was manually evaluated by 10 users. Each user scored from 1 to 10, and the softer the touch, the higher the score. The average score results of the 10 users are shown in Table 5 below.

[0576] [Table 5]

[0577]

[0578] As shown in Table 5, it has been confirmed that, compared with the biodegradable nonwoven fabrics of Comparative Examples 2-1 to 2-4, the biodegradable nonwoven fabrics of Examples 2-1 to 2-6 have an irreversible strain rate within a specific range or lower, and a rubbery plateau region in the temperature range of about 15°C to 40°C at which nonwoven fabrics are generally used. Therefore, they have excellent elasticity and a soft texture. Accordingly, the biodegradable nonwoven fabrics of Examples 2-1 to 2-6 are not only environmentally friendly, but also provide improved wearing comfort when used as sanitary materials in direct contact with the human body.

[0579] Industrial Applicability

[0580] The embodiments can be applied to biodegradable resin compositions and biodegradable molded articles including the same.

Claims

1. A biodegradable resin composition comprising: a first biodegradable resin comprising a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid; and Crystallization accelerator, wherein the crystallization promoter is included in an amount of 100 ppm to 50,000 ppm, and The isothermal crystallization time at 90°C is between 10 seconds and 900 seconds according to the following measurement method 1: [Measurement method 1] 1) heating the biodegradable resin composition to 220° C. at a heating rate of 10° C. / min, and then maintaining the temperature for 5 minutes; 2) Next, cooling the biodegradable resin composition to 90° C. at a cooling rate of 100° C. / min, and maintaining the isothermal state for 100 minutes; 3) Using differential scanning calorimetry, the time for the total area of ​​the crystallization peak of the biodegradable resin composition to be reduced by half is measured.

2. The biodegradable resin composition according to claim 1, wherein The crystallization accelerator includes at least one of an organic nucleating agent and an inorganic nucleating agent.

3. The biodegradable resin composition according to claim 2, wherein The biodegradable resin composition includes the organic nucleating agent in an amount of about 10 ppm to about 5,000 ppm.

4. The biodegradable resin composition according to claim 2, wherein The biodegradable resin composition includes the inorganic nucleating agent in an amount of about 100 ppm to about 10,000 ppm.

5. The biodegradable resin composition according to claim 1, wherein The biodegradable resin composition further includes an external lubricant.

6. The biodegradable resin composition according to claim 1, wherein The biodegradable resin composition has a tensile strength of 25 MPa or more according to the following measurement method 2: [Measurement method 2] 1) preparing the biodegradable resin composition into a sample having a thickness of 300 μm; 2) For the specimen, the tensile strength was measured at a rate of 100 mm / min using a universal testing machine.

7. A biodegradable nonwoven fabric comprising: A biodegradable resin composition, the biodegradable resin composition comprising a first biodegradable resin, the first biodegradable resin comprising a diol, an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid, Wherein, the biodegradable resin composition has a first irreversible strain rate of less than 30% measured by the following test method 3: [Measurement method 3] 1) compressing the biodegradable resin composition at 200° C. under a pressure of 20 MPa while placing the biodegradable resin composition between a pair of flat stainless steel molds to produce a biodegradable resin composition sheet having a thickness of 300 μm; 2) cutting the biodegradable resin composition sheet to produce a sample including a test part having a width of 3.18 mm and a length of 25 mm; 3) pulling the test component in the longitudinal direction at a speed of 10 mm / min at room temperature, wherein the test component is pulled 40% more than its total length; 4) In the absence of external force, the test component is allowed to recover at room temperature for 5 minutes; 5) The first irreversible strain rate is obtained by the following equation 1: [Equation 1] The first irreversible strain rate=(length of the test segment after recovery-25 mm) / 25 mm.

8. The biodegradable nonwoven fabric according to claim 7, wherein: The biodegradable resin composition has a second irreversible strain rate of less than 20% measured by the following Test Method 4: [Measurement method 4] 1) compressing the biodegradable resin composition at 200° C. under a pressure of 20 MPa while placing the biodegradable resin composition between a pair of flat stainless steel molds to produce a biodegradable resin composition sheet having a thickness of 300 μm; 2) cutting the biodegradable resin composition sheet to produce a sample including a test part having a width of 3.18 mm and a length of 25 mm; 3) pulling the test component in the longitudinal direction at a speed of 10 mm / min at room temperature, wherein the test component is pulled 30% more than its total length; 4) In the absence of external force, the test component is allowed to recover at room temperature for 5 minutes; 5) The second irreversible strain rate is obtained by the following equation 2: [Equation 2] The second irreversible strain rate=(length of the test segment after recovery-25 mm) / 25 mm.

9. The biodegradable nonwoven fabric according to claim 7, wherein: The biodegradable resin composition has a third irreversible strain rate of less than 10% measured by the following measurement method 5: [Measurement method 5] 1) compressing the biodegradable resin composition at 200° C. under a pressure of 20 MPa while placing the biodegradable resin composition between a pair of flat stainless steel molds to produce a biodegradable resin composition sheet having a thickness of 300 μm; 2) cutting the biodegradable resin composition sheet to produce a sample including a test part having a width of 3.18 mm and a length of 25 mm; 3) pulling the test component in the longitudinal direction at a speed of 10 mm / min at room temperature, wherein the test component is pulled 20% more than its total length; 4) In the absence of external force, the test component is allowed to recover at room temperature for 5 minutes; 5) The third irreversible strain rate is obtained by the following equation 3: [Equation 3] The third irreversible strain rate=(length of the test segment after recovery-25 mm) / 25 mm.

10. The biodegradable nonwoven fabric according to claim 7, wherein: The biodegradable resin composition has a fourth irreversible strain rate of less than 5% measured by the following Measurement Method 6: [Measurement method 6] 1) compressing the biodegradable resin composition at 200° C. under a pressure of 20 MPa while placing the biodegradable resin composition between a pair of flat stainless steel molds to produce a biodegradable resin composition sheet having a thickness of 300 μm; 2) cutting the biodegradable resin composition sheet to produce a sample including a test part having a width of 3.18 mm and a length of 25 mm; 3) pulling the test component in the longitudinal direction at a speed of 10 mm / min at room temperature, wherein the test component is pulled 10% more than its total length; 4) In the absence of external force, the test component is allowed to recover at room temperature for 5 minutes; 5) The fourth irreversible strain rate is obtained by the following equation 4: [Equation 4] The fourth irreversible strain rate=(length of the test segment after recovery-25 mm) / 25 mm.

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