KR20150068236A - Biodegradable copolymer for biodegradable sealant film preparation of low-temperature sealing and easy peeling, and biodegradable sealant film using the same - Google Patents

Abstract

The present invention relates to a copolymer for preparing a biodegradable sealant film having a low-temperature sealing and an easy peel and a biodegradable sealant film having a low-temperature sealing and an easy peel using the same wherein the copolymer is biodegradable and has a low-temperature sealing and an easy peel and further has superior seal strength, peel strength, tensile strength, elongation, coefficient of friction, oxygen permeability and moisture permeability, and safety against toxicity and thus can be suitably used as a packaging material.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a biodegradable copolymer and a biodegradable sealant film for use in the production of a biodegradable sealant film,

The present invention is not only capable of biodegradability, low temperature sealing and easy peel, but also excellent in sealing strength, peel strength, tensile strength, elongation, friction coefficient, oxygen permeability, water permeability and toxicity, The present invention relates to a low temperature sealing and a biodegradable sealant film for use in the production of a biodegradable sealant film.

The packaging used for wrapping or packing goods is out of the functional aspect for conventional distribution, and packaging of various types of sub-types according to the diversified lifestyle changes is increasing, and convenience and aesthetics according to packaging are also required have. Paper and plastics are representative examples of packaging materials that can meet these demands, and the share of plastic packaging materials with a wide range of applications is expanding. Looking at the composition of raw materials for packaging containers in the global packaging market, plastic accounts for 30%, followed by paper products (39%).

Plastics are used in a variety of industries as well as packaging materials. The demand for plastics has increased by an average of 5.5% per year since 1990, and this trend is expected to continue until 2015, with Asia accounting for 15 kg of plastic per capita Has become the center of growth. Korea uses 80 kg of plastic per person per year, so it is an advanced country in terms of plastic use.

However, recently, the problem of environmental pollution due to the use of plastics has been rising, and there is an increasing awareness of recycling of plastics, and legal regulations and technological developments have been made nationwide. As the use of plastics increases, the issue of wastes is being socially sought, and it is necessary to recover and recycle used plastic waste. However, plastic film waste used as a packaging material is difficult to recover and recycle. Therefore, most of it is depended on disposal such as landfill or incineration, and environmental pollution problems such as air pollution, dioxin detection and environmental hormone leakage due to incomplete combustion of waste .

To solve this problem, the development of a biodegradable sealant film having the same physical properties as those of a conventional sealant film by using biodegradable materials decomposed into water and carbon dioxide by microorganisms at the time of embedding or disposing a plastic film used as a packaging material Is required.

Such a biodegradable sealant film should have the same function as that of ordinary plastics in use and have a property of being decomposed by microorganisms in the soil after use. Generally, a film is composed of multiple layers such as a coating layer, a printing layer, a barrier layer, and a sealing layer. If the film is not made into a biodegradable film while maintaining the function of each layer, biodegradability of the entire film composed of each layer is achieved It is very difficult to manufacture each of the biodegradable sealant films.

The purpose of the packaging material is to preserve the quality and safety of the contents during the entire process from the producer to the consumer. Especially, in case of flexible packaging materials, the sealing material . Such sealing generally means wrapping the contents with the packaging material and sealing it, wherein the packaging material is applied in a sealed manner by applying a high temperature. However, since such a high temperature is usually required to be 180 DEG C or higher, a large amount of energy is used when a high-speed packaging system is applied, which is not preferable from the packaging cost standpoint.

EJUIL PACKING MATERIAL is made of polymers with different compatibility and shows the characteristics of EZIPHIL with appropriate adhesive strength by proper balance of compatibility / non-compatibility between substrate and film when heat-sealing to adhesive base material. The selection of polymers with different compatibility, and the control of the morphology of the continuous phase and dispersed phase between them. Particularly, when the sealing temperature of the packaging material is high, since the packaging material can be deformed, the lower the sealing temperature is, the better, and the packaging is performed in the form of an automatic packaging, so the productivity depends on the characteristics of the adhesive film.

Therefore, it is urgently required to develop a packaging material having a low sealing temperature and an easy paper property while maintaining the characteristics of the conventional biodegradable sealant film.

Accordingly, the inventors of the present invention completed the present invention by studying various packaging materials, confirming that the copolymer according to the specification of the present invention improves the properties of the required packaging material, in particular, has a low sealing temperature and an easy paper property .

The present invention relates to a low-temperature sealing material which can be used as a packaging material because of its excellent biodegradability, low temperature sealing and easiness, and excellent sealing strength, peel strength, tensile strength, elongation, friction coefficient, oxygen permeability, water permeability, And to provide a copolymer for the production of the biodegradable sealant film of the present invention and a low temperature sealing and biodegradable sealant film using the same.

In order to solve the above problems, the present invention provides a copolymer for producing low-temperature sealing and an easy-to-use biodegradable sealant film prepared by copolymerizing the following components.

i) polylactic acid (PLA); ii) 1 to 3 kinds of acrylic monomers; And iii) a first copolymer prepared by copolymerizing an acrylic monomer having a multifunctional group (component A);

Polybutylene succinate (PBS); Polybutylene adipate terephthalate (PBAT); Or a mixture thereof (component B);

Polycaprolactone (PCL) (component C); And

Diisocyanate; Maleic anhydride (MAH); Maleic acid (MA); Fumaric acid (FA); Or a mixture thereof (component D).

The term "sealant film" used in the present invention means a film which is placed in the innermost layer of the packaging material for packaging contents and sealed by heat. Particularly, the sealant film of the present invention is capable of low-temperature sealing, and is characterized in that sealing is possible even at 150 DEG C or lower, more preferably 140 DEG C or lower. Since the low-temperature sealing is possible, it is characterized by using less energy than a conventional packaging system requiring a high temperature.

In addition, the sealant film according to the present invention has biodegradable properties, which is achieved by the first copolymer (component A). Said first copolymer comprising: i) polylactic acid (PLA); ii) 1 to 3 kinds of acrylic monomers; And iii) an acrylic monomer having a multifunctional group.

The acrylic monomers having one to three kinds of acrylic monomers and polyfunctional groups prevent the lowering of the melt viscosity due to the decrease in the molecular weight accompanied by the copolymerization process and maintain the proper viscosity required for processing.

The type of the acrylic monomer used in the first copolymer is not particularly limited, but polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT) and polycaprolactone (PCL) The acrylic monomer is appropriately selected to improve compatibility with the polymers to be copolymerized with each other, and is blended with a proper fraction to copolymerize with polylactic acid (PLA).

Preferably, the acrylic monomer is selected from the group consisting of acrylic acid (AA), methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), methyl methacrylate (MMA), hydroxyethyl acrylate ) Or ethylhexyl acrylate (EHA) can be used. Preferably, the acrylic monomer is ethylhexyl acrylate (EHA), hydroxyethyl acrylate (HEA) or butyl acrylate (BA). More preferably, ethylhexyl acrylate (EHA) is used alone, or ethylhexyl acrylate (EHA) and hydroxyethyl acrylate (HEA); Ethylhexyl acrylate (EHA) and butyl acrylate (BA); Or ethylhexyl acrylate (EHA), hydroxyethyl acrylate (HEA) and butyl acrylate (BA) can be used.

The acrylic monomer having a polyfunctional group may be an acrylic acid alkyl ester monomer, a urethane acrylate monomer, an acrylamide monomer, a styrene monomer or an N-vinylamide monomer. Preferably, glycidyl acrylate (GA), glycidyl methacrylate (GMA) or glycidyl butylate (GBA) can be used, and more preferably glycidyl methacrylate (GMA) Can be used.

As used herein, the term " poly (lactic acid), PLA) " means a polymer comprising lactic acid units. Specifically, the lactic acid may be L-lactic acid, D-lactic acid, or a combination thereof. In the present invention, the polylactic acid may contain 50 mol% or more, preferably 50 to 80 mol%, of the lactic acid unit. The polylactic acid may contain, in addition to the lactic acid unit,? -Hydroxy acid (i.e., glycolic acid), 3-hydroxybutyric acid, 3-hydroxyvaleric acid, 3-hydroxycaproic acid, Is not limited.

The molecular weight of the polylactic acid (PLA) is 100,000-200,000 g / mol, preferably 120,000-150,000 g / mol, and more preferably 130,000-140,000 g / mol.

Due to the structural and crystallization characteristics of linearity, high processing temperature, low melt viscosity and weak melt strength, polylactic acid can not be produced by general inflation or blown processes, In the case of sheet production using the die method, the produced sheet is brittle and easily broken, and there is a limitation in processing sheets or films using poly (lactic acid).

Therefore, it is necessary to modify the polylactic acid in order to overcome such disadvantages. In the present invention, it is modified by using one to three types of acrylic monomers and acrylic monomers having polyfunctional groups.

By using the acrylic monomers having one to three types of acrylic monomers and polyfunctional groups, the melt index (MI) of the resin composition is lowered to remarkably increase the melt viscosity of the poly (lactic acid) (MI 5 or less, g / 10 min 占 200 占 폚, 2.16 kg) It is possible to improve film processability. The poly (lactic acid) used in the preparation of the first copolymer is modified as described above under melt kneading in a twin screw extruder to exhibit improved properties and a film can be produced by the inflation method.

For the preferred melting characteristics of the first copolymer, the weight ratio of the one to three kinds of acrylic monomers and polyfunctional acrylic monomers is preferably 10: 1 to 10: 3. The weight ratio (PLA: AMM + MFM) of polylactic acid (PLA), 1 to 3 kinds of acrylic monomer (AMM) and polyfunctional acrylic monomer (MFM) is preferably 50-95: 50-5, -95: 15-5 is more preferable.

The first copolymer may be prepared by a commonly used copolymerization method, for example, by melt-kneading in a twin screw extruder. Specifically, the melt-kneading is preferably performed by connecting a vacuum pump to a barrel of a biaxial screw extruder and performing melt-kneading under a vacuum of -1 kgf / cm 2 or less. The biaxial screw may be used by mixing and arranging a metering section, a compression section, and a mixing section. Preferably, the biaxial screw may be composed of a first metering section, a compression section, a mixing section, a second metering section, a compression section, Part, and compression section.

In the preparation of the first copolymer, polylactic acid (PLA) is passed through a first metering section to melt a mixture of one to three kinds of acrylic monomers (AMM) and an acrylic monomer (MFM) It is preferable to inject the solution through the portion. In addition, the above-mentioned one to three kinds of acrylic monomer (AMM) and the acrylic monomer (MFM) having a polyfunctional group can be injected by using a liquid injection pump, preferably a high pressure metering pump capable of injecting up to 10 bar have. The melt-kneading may be carried out at 160 to 230 ° C, preferably 200 ° C.

In the preparation of the first copolymer, when a highly reactive acrylic monomer (AMM) and an acrylic monomer (MFM) having a multifunctional group are used, a copolymer can be produced without addition of a peroxide initiator, A peroxide initiator may be further used to facilitate the modification of the catalyst. Examples of the peroxide initiator include di-t-butyl peroxide, dicumyl peroxide, di-t-amyl peroxide, 2,5-dimethyl-2,5-di (t- butylperoxy) Peroxybenzoate, and the like can be used alone or in combination. In the present invention, the content of the peroxide initiator may be 0.01 to 5 parts by weight based on 100 parts by weight of the total of the poly (lactic acid) and the monomers.

The first copolymer prepared as described above is used for the production of a copolymer for the production of a low-temperature sealing and an urethane biodegradable sealant film (second copolymer), which will be described below, without further processing.

A second copolymer for producing a low-temperature sealing and an easy-to-use biodegradable sealant film is prepared by adding a component having a low melting point and copolymerizing the first copolymer in such a manner that not only low- (PBS), polybutylene adipate terephthalate (PBAT), or a mixture thereof (component B); Polycaprolactone (PCL) (component C); And a diisocyanate, maleic anhydride (MAH), maleic acid (MA), fumaric acid (FA), or a mixture thereof (component D). The diisocyanate may be toluene diisocyanate (TDI), 1,4-phenylene diisocyanate (PDI), or methylene diisocyanate (MDI). In place of the diisocyanate, maleic anhydride (MAH), maleic acid (MA), and fumaric acid (FA) may be used. Also, diisocyanate, maleic anhydride (MAH), maleic acid (MA) and fumaric acid (FA) may be used in combination, but they are preferably used alone or as a mixture of one or two kinds. .

(PBS) and / or polybutylene adipate terephthalate (PBAT) and polycaprolactone (PCL) to a main chain of the first copolymer with diisocyanate, maleic anhydride (MAH), maleic anhydride The copolymer can be prepared through the chemical bonding of polylactic acid (PLA) with a waxy acid (MA), a fumaric acid (FA), or a mixture thereof, and a low-temperature sealing and an isophilic character can be given according to an appropriate blend ratio.

In the above, the molecular weight of polybutylene succinate (PBS) is 2,000-40,000 g / mol, preferably 2,200-20,000 g / mol. The molecular weight of polybutylene adipate terephthalate (PBAT) is 70,000-200,000 g / mol, preferably 100,000-150,000 g / mol. The molecular weight of polycaprolactone (PCL) is 7,000-15,000 g / mol, preferably 8,000-10,000 g / mol.

The polymer main chain, which is the base of the polylactic acid (PLA; Tm 152 ° C, Tg 58 ° C), is relatively low in polycaprolactone (PCL) having a low melting temperature or a low glass transition temperature (PBT; Tm 110-115 ° C, Tg-30 ° C) and polybutylene stearate (PBS; Tm 114 ° C, Tg -45 ° C) or polybutylene adipate terephthalate (PCL) and polybutylenesuccinate (PBS) at a relatively low temperature when heat is applied for adhesion, because the polymer is randomly distributed in the polylactic acid (PLA) (PLA) at the lower temperature by weakening the intermolecular force between the main chain polylactic acid (PLA) and the polymer chain movement of polybutylene adipate terephthalate (PBAT) and / or polybutylene adipate terephthalate (heat sealing) becomes possible.

 Further, when a suitable ratio of the copolymerization of polycaprolactone (PCL), polybutylene succinate (PBS) and / or polybutylene adipate terephthalate (PBAT) is applied to a continuous phase polylactic acid (PLA) matrix (PLA) molecules having a structure in which discontinuous phase polycaprolactone (PCL), polybutylene succinate (PBS) and / or polybutylene adipate terephthalate (PBAT) But the molecular chains of the polymer having a low compatibility with each other are not bonded to each other, so that a copolymer resin having an interfacial failure type isomer function can be obtained.

In addition, the peeling force required for peeling from each other is the same as that of the base polymer (PLA), the combination of polycaprolactone (PCL), polybutylene succinate (PBS) and / or polybutylene adipate terephthalate Adjustable by adjusting the ratio. The mixing ratio of the components A, B, D and C is preferably 60-90: 4-28: 0.2-0.5: 1-15.

The copolymer for the low-temperature sealing and the preparation of the biodegradable sealant film of the present invention may be prepared by a commonly used copolymerization method. For example, the first copolymer may be mixed with polybutylene succinate (PBS) and polycaprolactone (PCL) may be mixed first, and 1,4-phenylenediisocyanate (PDI) may be mixed and extruded. Like the first copolymer, melt-kneading in a twin-screw extruder. In this case, unlike the preparation of the first copolymer, it is preferable not to use a peroxide as a catalyst.

The melt-kneading may be carried out at 160 to 230 ° C, preferably 200 ° C. Further, it is more preferable that the vacuum pump is connected to the barrel of the biaxial screw extruder and the melt-kneading is performed in a vacuum state of -1 kgf / cm 2 or less.

In addition, a film can be produced using the copolymer for low-temperature sealing and the method for producing an ejb-containing biodegradable sealant film (second copolymer). The thickness of the film can be appropriately adjusted according to the application in which the packaging material is used, and preferably, it can be adjusted to 20 to 100 mu m. The production of the film may be performed by a commonly used method, for example, a method using a T-die and a method using blown (or inflation). A blown method is more preferable for producing a film having a thickness of 50 μm or less.

The biodegradable sealant film according to the present invention is characterized by being capable of low-temperature sealing and easy peeling, and excellent in sealing strength, peel strength, tensile strength, elongation, friction coefficient, oxygen permeability, water permeability and toxicity.

First, the sealant film of the present invention has biodegradability, and such biodegradability can be evaluated by biodegradation according to KS M 3100-1 (ISO 14855). In the present invention, the biodegradability is preferably 90% or more

In addition, the sealant film of the present invention is capable of low-temperature sealing, preferably sealing at not more than 150 DEG C, more preferably not more than 140 DEG C, and is capable of sealing at a low temperature, It uses less energy than the system. In one embodiment of the present invention, it was confirmed that the sealant film of the present invention can be sealed even at 140 ° C or lower.

Further, the sealant film of the present invention is characterized in that the sealing strength is excellent. The sealing strength can be measured in accordance with KS M ISO 11339, and preferably has a sealing strength of at least 15 N / 20 mm.

Further, the sealant film of the present invention is characterized in that easy peel is possible. The Izapil can be measured according to KS M ISO 11339, and is characterized by being capable of easy peeling at a rate of 15 N / 20 mm or less, more preferably 12-15 N / 20 mm, So that it can be used for a tray product requiring a conventional ejipil.

Further, the sealant film of the present invention is characterized by being excellent in tensile strength. The tensile strength can be measured according to KS M 3054, and preferably has a tensile strength of 25 MPa or more.

Further, the sealant film of the present invention is characterized in that it has excellent elongation. The elongation percentage can be measured according to KS M 3054, and preferably has an elongation of 120% or more.

Further, the sealant film of the present invention is characterized in that it has excellent friction coefficient. The coefficient of friction can be measured according to ASTM D 1894, and preferably has a coefficient of friction of 0.12 to 0.16.

Further, the sealant film of the present invention is characterized by being excellent in oxygen permeability. The oxygen permeability can be measured according to ASTM D 3985, and preferably has an oxygen permeability of 20 cm < 3 > / mm < 2 >

Further, the sealant film of the present invention is characterized by being excellent in water permeability. The water permeability can be measured according to ASTM F 1249, and preferably has a water permeability of 10 g · mm / m 2 · 24h or less.

Further, the sealant film of the present invention is characterized by being excellent in toxicity safety. Toxicity safety can be measured by the dissolution test according to the standards and standards of the Food and Drug Administration, 7th Agency for Food, Drug, and Health (KFDA), containers and packaging, preferably 0.01 mg / L of lead (Pb) Less evaporation residues less than 2 mg / L in water, less than 4 mg / L evaporation residue in n-heptane, less than 20 mg / L in n-heptane, less than 1 mg / L potassium permanganate consumption, Evaporation residue in ethanol can have up to 2 mg / L.

As described above, the low-temperature sealing and the easy-to-handle biodegradable sealant films according to the present invention are not only biodegradable, low temperature sealing and easy peelable, but also excellent in sealing strength, peel strength, tensile strength, elongation, coefficient of friction, oxygen permeability, And toxicity safety, it can be suitably used as a packaging material.

FIG. 1A shows the 1 H-NMR analysis results of the first copolymer according to one embodiment of the present invention, and FIG. 1B shows the results of ¹³ C-NMR analysis of the first copolymer. FIG. 1C shows the results of ¹ H-NMR analysis of polylactic acid used in one embodiment of the present invention, and FIG. 1D shows the results of ¹³ C-NMR analysis of polylactic acid.
2 shows a DSC analysis result of the copolymer according to an embodiment of the present invention. (A first copolymer) prepared in step 1 of the embodiment; Fig. 2 (c) is a cross-sectional view taken along the line II-II of Fig. 2 The polylactic acid (PLA) used, the polycaprolactone (PCL) used in FIG. 2D, and the polybutylene succinate (PBS) used are shown in DSC analysis.
Figure 3 is an electron microscope (SEM) image of the appearance of a low-temperature sealing and an e-paper biodegradable sealant film according to an embodiment of the present invention. FIG. 3A shows a cross-sectional observation result, and FIG. 3B shows a surface observation result.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided to further understand the present invention, and the present invention is not limited by the examples.

Example : Low temperature sealing and Ezipil ( easy peel ) Preparation of Copolymers for the Preparation of Biodegradable Sealant Films

Step 1) Poly lactic acid ( PLA ), Acrylic Monomer ( AMM ) And Multifunctional  acryl The monomer (MFM) (First copolymer)

90 parts by weight of polylactic acid (PLA, molecular weight 130,000-140,000 g / mol, NatureWorks LLC, USA), and a monomer containing an acrylic monomer (AMM) and a polyfunctional acrylic monomer (MFM) And 10 parts by weight of 0.3 part by weight of melper oxide were extruded from a twin screw extruder (32 mm, L / D 36) at an extrusion bed temperature of 200 캜 and a die outlet temperature of 165 캜 to be cut into pellets to obtain a biodegradable first copolymer resin A composition was obtained.

division Monomer (parts by weight) 2-ethylhexyl acrylate (EHA) 2-hydroxyethyl acrylate (HEA) Butyl acrylate (BA) Glycidyl methacrylate (GMA) Example 1 9.4 0.0 0.0 0.6 Example 2 8.8 0.0 0.0 1.2 Example 3 8.2 0.0 0.0 1.8 Example 4 7.6 0.0 0.0 2.4 Example 5 7.4 2.0 0.0 0.6 Example 6 6.8 2.0 0.0 1.2 Example 7 6.2 2.0 0.0 1.8 Example 8 5.6 2.0 0.0 2.4 Example 9 7.3 1.5 0.0 1.2 Example 10 5.8 3.0 0.0 1.2 Example 11 3.8 5.0 0.0 1.2 Example 12 0.8 8.0 0.0 1.2 Example 13 0.0 8.8 0.0 1.2 Example 14 8.8 0.0 2.0 1.2 Example 15 7.8 1.0 2.0 1.2 Example 16 5.8 3.0 2.0 1.2 Example 17 0.0 2.0 6.2 1.8 Example 18 0.0 6.2 2.0 1.8 Example 19 0.0 4.1 4.1 1.8 Example 20 4.8 3.0 3.0 1.2

Step 2) Low temperature sealing and Ezipil  Preparation of Copolymer (Second Copolymer) for Preparation of Biodegradable Sealant Film

(PBS), polycaprolactone (PCL), and 1,4-phenylenediisocyanate (PDI) in the mixing ratios shown in Table 2 were mixed in a mixture of 79.8 parts by weight of the first copolymer prepared in Step 1, Were extruded from a twin screw extruder (32 mm, L / D 36) at an extrusion bed temperature of 200 ° C and a die exit temperature of 165 ° C and cut into pellets to obtain a biodegradable second copolymer resin A resin for producing a sealant film) composition was obtained.

division Weight portion The first copolymer Polybutylenesulfonate (PBS) Polycaprolactone
(PCL) 1,4-phenylene diisocyanate (PDI) Example 1 79.8 18.9 1.0 0.3 Example 2 79.8 17.9 2.0 0.3 Example 3 79.8 14.9 5.0 0.3 Example 4 79.8 12.9 7.0 0.3 Example 5 79.8 10.9 9.0 0.3 Example 6 79.8 8.9 11.0 0.3 Example 7 79.8 6.9 13.0 0.3 Example 8 79.8 4.9 15.0 0.3 Example 9 79.8 18.7 1.0 0.5 Example 10 79.8 17.7 2.0 0.5 Example 11 79.8 14.7 5.0 0.5 Example 12 79.8 12.7 7.0 0.5 Example 13 79.8 10.7 9.0 0.5 Example 14 79.8 8.7 11.0 0.5 Example 15 79.8 6.7 13.0 0.5 Example 16 79.8 4.7 15.0 0.5

Step 3) Low temperature sealing and Ezipil  Preparation of Biodegradable Sealant Film

1,000 kg of the second copolymer prepared in the step 2 was dried in a tray-form dry chamber set at 60 ° C. for 12 hours or more, and the temperature was adjusted to the temperature shown in Table 3 below. A single screw extruder diameter 50 cm) to obtain a low-temperature sealing and an easy-to-use biodegradable film.

division Extrusion temperature (캜) Extrusion speed (rpm) Resin pressure (bar) Film thickness (탆) cylinder One 2 3 4 Adapter Die Example 1 160 160 170 170 170 170 12 160 28 ± 3 Example 2 160 160 170 170 170 170 12 160 33 ± 2 Example 3 160 160 170 170 170 170 12 170 39 ± 3 Example 4 160 160 170 170 170 170 12 180 45 ± 3

Experimental Example  One

In order to confirm whether or not the first copolymer prepared in step 1 of the above example was prepared, solution NMR analysis was performed using CDCl ₃ as a solvent having a resolution of 500 MHz, and the results are shown in FIG. For comparison, the results were compared with the NMR analysis results of the first copolymer prepared in step 1 of the above example (Figs. 1A and 1B), and the polylactic acid (PLA) used (Figs. 1C and 1D).

¹ H-NMR analysis results, in the Figure 1c on the other hand, only the characteristic peaks of PLA Original _{Methyl group (-CH 3, 1.554 ppm} ) and Methine group (-CH, 5.189 ppm) indicated, in Figure 1a Properties of PLA Original Peak (-CH ₃ , 0.907 ppm), Vinyl group (CH ₂ -CH, 1.839), which are the characteristic peaks of the monomers used, in addition to the methyl group (-CH ₃ , 1.606 ppm) ppm), a methylene group (-CH ₂ , 3.745 ppm), and an epoxy group (5.8-6.36 ppm).

In addition, ¹³ C-NMR analysis of the results, Fig. 1d the characteristic peaks of _{PLA Original Methyl group (-CH 3,} 16.854 ppm), Methine group (-CH, 69.232 ppm) and Carboxyl group (-C = O, 169.802 ppm ), Whereas in Figure 1B, in addition to the characteristic peaks of PLA Original (-CH ₃ , 16.859 ppm), Methine group (-CH, 69.232 ppm) and Carboxyl group (-C═O, 169.798 ppm) It was confirmed that the characteristic peak of the monomer, the methylene group (-CH ₂ , 25.827 ppm, 68.186 ppm) appeared. From the above results, it was confirmed that a copolymer containing a new monomer was formed.

Experimental Example  2

DSC analysis was performed to confirm whether the copolymer for the production of a low-temperature sealing and an easy-to-use biodegradable sealant film (the second copolymer) prepared in the step 2 of the above Example was produced. The results are shown in FIG. 2b) and the polylactic acid (PLA) used (Fig. 2c), polycaprolactone (PCL) (Fig. 1d) and polybutylene succinate PBS) (Figure 1 e).

As can be seen from Figs. 2A to 2E, in the copolymer for producing a low-temperature sealing biodegradable sealant film prepared in step 2 of the above example, the characteristics of PCL and PBS were shown in addition to the copolymer prepared in step 1 of the above example It was confirmed that the components used were copolymerized.

Experimental Example  3

The appearance of the low-temperature sealing biodegradable sealant film produced in the above example was confirmed by an electron microscope (SEM) image, and the results are shown in Fig. 3a (cross-sectional observation result) and Fig. 3b (surface observation result).

Experimental Example  4

The characteristics of the low temperature sealing biodegradable sealant prepared in the above examples were confirmed under the following conditions.

1) Biodegradability test

- Test method: Determination of the Ultimate Aerobic Biodegradability and Disintegration of Plastic Materials Under Controlled Composting Conditions (Part 1: Analysis of Evolved Carbon Dioxide by Titration Method (KS M 3100-1)

- Method of analysis of generated carbon dioxide: titration

- Test vessel volume: 2 L

- Test temperature: 58 ± 2 ℃

- Exam period: 45 days

2) Sealing strength test

- Test method: KS M ISO 11339 (T-type peel test of adhesive-soft-soft material bonded assembly)

- Tester: UTM (WITHLAB company / WL2100)

- Test speed: 50 mm / min

- Load cell: 200 N

- Peeling angle: 180 °

- Sealing temperature: 140 ℃

- Test unit: CGS unit system, SI (MKS) system unit

- Test temperature: 23 ± 2 ℃, 45 ± 5% RH

3) peel strength test

- Test method: KS M ISO 11339 (T-type peel test of adhesive-soft-soft material bonded assembly)

- Tester: UTM (WITHLAB company / WL2100)

- Test speed: 10 mm / min

- Load cell: 200 N

- Peeling angle: 180 °

- Sealing temperature: 140 ℃

- Test unit: CGS unit system, SI (MKS) system unit

- Test temperature: 23 ± 2 ℃, 45 ± 5% RH

- Average peel interval: 7 to 20 mm

4) The tensile strength  And elongation test

- Test method: KS M 3054 (tensile test method of plastic film and sheet)

- Tester: UTM (WITHLAB company / WL2100)

- Test speed: 10 mm / min

- Load cell: 200 N

- Gauge distance: 50 mm

- Test unit: CGS unit system, SI (MKS) system unit

- Test temperature: 23 ± 2 ℃, 45 ± 5% RH

5) Friction test

- Test method: ASTM D 1894 (Standard Test Method for Static and Kinetic Coefficients of Friction of Plastic Film and Sheeting)

- Tester: UTM (WITHLAB company / WL2100)

- Test speed: 150 mm / min

- Load cell: 20 N

- Vertical load: 1.96 N

- Average section: 10 to 50 mm

- Test unit: CGS unit system, SI (MKS) system unit

- Test temperature: 23 ± 2 ℃, 45 ± 5% RH

- friction material and friction material: biodegradable sealant film and biodegradable sealant film

6) Oxygen permeability test

Test Method: ASTM D 3985 (Standard Test Method of Oxygen Gas Transmission Rate Through Plastic Film and Sheeting Using a Coulometric Sensor)

- Tester: OX-TRAN, Model 2/21 (MOCON, USA)

- Test temperature: (25 ± 2) ℃, (50 ± 5)% RH

- Test time: 30 minutes

- Measurement range: 0.01 to 2000 cm3 / m < 2 >, 24 hr-atm)

- N ₂ flow rate: 10 sccm

- Measuring mode: M5

7) Toxicity safety test

- Test method: Food revolution Article 7. Standards and specifications of utensils, containers and packaging

The results measured under the above test conditions are shown in Tables 4 and 5 below.

Evaluation items unit Evaluation results Assessment Methods Biodegradability % 94.5 KS M 3100-1 Sealing temperature ℃ 140 - Sealing strength N / 20 mm 15.0 KS M ISO 11339 Peel strength N / 20 mm 13.5 KS M ISO 11339 The tensile strength MPa 45.0 KS M 3054 Elongation rate % 130 KS M 3054 Coefficient of friction - 0.12 ASTM D 1894 Oxygen permeability cc · mm / ㎡ · day · atm 18 ASTM D 3985 Water permeability g · mm / m 2 · 24 h 10 ASTM F 1249

Evaluation items Test Methods unit Specification standard Test result Toxicity safety Dissolution test Lead (Pb) mg / L 1.0 or less Non-detection
(Detection limit 0.01) Potassium permanganate consumption below 10 One Evaporation residue With 4% acetic acid 30 or less 6 with water 30 or less 2 with n-heptane 30 or less 4 With 20% ethanol 30 or less 2 Test regulations Food revolution 7. Standards and specifications of utensils, containers and packaging

Claims (22)

i) polylactic acid; ii) 1 to 3 kinds of acrylic monomers; And iii) a first copolymer prepared by copolymerizing an acrylic monomer having a multifunctional group (component A);
Polybutylene succinate; Polybutylene adipate terephthalate; Or a mixture thereof (component B);
Polycaprolactone (component C); And
Diisocyanate; Maleic anhydride; Maleic acid; Fumaric acid; Or a mixture thereof (component D)
Copolymer for the manufacture of low temperature sealing biodegradable sealant films.
The process of claim 1, wherein the acrylic monomer is acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, methyl methacrylate, hydroxyethyl acrylate or ethylhexyl acrylate. The low temperature sealing biodegradable sealant Copolymers for making films.
The method according to claim 1, wherein the one to three kinds of acrylic monomers are selected from the group consisting of ethylhexyl acrylate alone; Ethylhexyl acrylate and hydroxyethyl acrylate; Ethylhexyl acrylate and butyl acrylate; Or a copolymer of ethylhexyl acrylate, hydroxyethyl acrylate and butyl acrylate, for producing a low temperature sealing biodegradable sealant film.
The method according to claim 1, wherein the polyfunctional group is an acrylic monomer, an acrylic acid alkyl ester monomer, a urethane acrylate monomer, an acrylamide monomer, a styrene monomer or an N-vinylamide monomer. Copolymers for the manufacture of sealant films.
The copolymer for producing a low-temperature sealing biodegradable sealant film according to claim 1, wherein the polyfunctional group is acrylic monomer, glycidyl acrylate, glycidyl methacrylate or glycidyl butylate.
The copolymer for producing a low-temperature sealing biodegradable sealant film according to claim 1, wherein the weight ratio of the acrylic monomers having 1 to 3 kinds of monomers to the acrylic monomers having polyfunctional groups is 10: 1 to 10: 3.
[2] The method according to claim 1, wherein the weight ratio (PLA: AMM + MFM) of the polylactic acid (PLA) to the acrylic monomer (AMM) having one to three kinds of monomers and the multi- Wherein the low-temperature sealing biodegradable sealant film is a copolymer for producing a low temperature sealing biodegradable sealant film.
[8] The method according to claim 7, wherein the weight ratio (PLA: AMM + MFM) of the polylactic acid (PLA) to the acrylic monomers (MFM) having one to three kinds of acrylic monomers (AMM) Wherein the low-temperature sealing biodegradable sealant film is a copolymer for producing a low temperature sealing biodegradable sealant film.
The copolymer for producing a low temperature sealing biodegradable sealant film according to claim 1, wherein the component D is a diisocyanate, a maleic anhydride, a maleic acid or a fumaric acid, or a mixture of two kinds thereof.
The copolymer according to claim 1, wherein the diisocyanate is toluene diisocyanate, 1,4-phenylene diisocyanate or methylene diisocyanate.
The low temperature sealing biodegradable sealant film according to claim 1, wherein the mixing ratio of the component A, component B, component D and component C is 60-90: 4-28: 0.2-0.5: 1-15. Copolymers for manufacture.
A low temperature sealing biodegradable sealant film comprising a copolymer for producing a low temperature sealing biodegradable sealant film of any one of claims 1 to 11.
The low temperature sealing biodegradable sealant film according to claim 12, wherein the low temperature sealing biodegradable sealant film has a biodegradability measured according to KS M 3100-1 (ISO 14855) of 90% or more.
The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film is capable of sealing at 140 캜 or less.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has a seal strength measured according to KS M ISO 11339 of at least 15 N / 20 mm.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has a peel strength measured according to KS M ISO 11339 of 15 N / 20 mm or less.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has a tensile strength of at least 25 MPa as measured according to KS M 3054.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has an elongation of 120% or more as measured according to KS M 3054.
The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has a coefficient of friction of 0.12 to 0.16 as measured according to ASTM D 1894.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has an oxygen permeability measured according to ASTM D 3985 of 20 cm3 / mm2 24 hratm or less.
13. The low temperature sealing biodegradable sealant film of claim 12, wherein the low temperature sealing biodegradable sealant film has a moisture permeability measured according to ASTM F 1249 of less than or equal to 10 gmm / m < 2 >
13. The method of claim 12, wherein the low-temperature sealing biodegradable sealant film is a polyvinyl alcohol. A low-temperature sealing biodegradable sealant film characterized in that the components in the eluate measured according to the standards and specifications of apparatus, containers and packaging satisfy the following conditions:
Lead (Pb) in the eluate is not more than 0.01 mg / L,
Consumption of potassium permanganate 1 mg / L or less,
4% acetic acid, less than 6 mg / L of evaporation residue,
Evaporation from water 2 mg / L or less,
4 mg / L or less of evaporation residue in n-heptane, and
Evaporation residue in 20% ethanol 2 mg / L or less.

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