KR20210111188A - Preparation method of biodegradable articles - Google Patents

Abstract

The present invention relates to a method for manufacturing biodegradable articles. Specifically, according to one embodiment of the present invention, a method for manufacturing biodegradable articles comprises a step of forming a coating layer on at least one surface of a substrate through a coating process selected from a group consisting of a melt extrusion process, a solvent casting process, a wet coating process, and a lamination process so that an environmentally friendly coating layer with excellent biodegradability and biocompatibility can be effectively formed, thereby manufacturing biodegradable articles with excellent biodegradability, coatability, productivity, and processability.

Description

Method of manufacturing a biodegradable article {PREPARATION METHOD OF BIODEGRADABLE ARTICLES}

The present invention relates to a method for making a biodegradable article.

Recently, as concerns about environmental problems increase, research on the treatment of various household wastes and their recycling is being actively conducted. Specifically, inexpensive polymer materials with excellent processability and other properties are widely used to manufacture various products such as paper, films, fibers, packaging materials, bottles, containers, etc. Substances can be released, and it takes hundreds of years depending on the type to be completely decomposed in nature.

Therefore, it is possible to improve the eco-friendliness by decomposing in a short time, while improving the mechanical properties, oil resistance, water resistance and processability to increase the lifespan of the product itself, thereby reducing the amount of waste or improving recyclability. research is ongoing.

Polyhydroxyalkanoates (PHA) are biodegradable polymers composed of several types of hydroxy carboxylic acids produced by numerous microorganisms and used as intracellular storage materials. Polyhydroxyalkanoate is a conventional petroleum-derived polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (polybutylene succinate) It has properties similar to synthetic polymers such as terephthalate, PBST) and polybutylene succinate adipate (PBSA), and shows complete biodegradability and excellent biocompatibility.

On the other hand, in order to improve the service life and recyclability of various products such as paper, film, fiber, packaging materials, bottles, containers, etc., it is important to improve mechanical properties such as strength or water resistance and oil resistance. In order to improve these properties, a process of forming a coating layer on the surface of a product is used, but there is a problem in that the coatability, productivity and processability of the coating layer forming process are low, or biodegradability or recyclability is reduced due to the coating layer. Therefore, there is a need for the development of a biodegradable article with excellent biodegradability and biocompatibility and excellent coating properties, productivity and processability, and excellent dispersibility, dispersion stability, storage stability and coatability, and a method for effectively manufacturing the same. am.

Korean Patent Publication No. 2012-0103158

Accordingly, an object of the present invention is to provide a method for manufacturing a biodegradable article that is environmentally friendly and can improve coatability, productivity and processability due to excellent biodegradability and biocompatibility.

The method for manufacturing a biodegradable article according to an embodiment of the present invention includes forming a biodegradable coating layer on at least one surface of a substrate through a coating process selected from the group consisting of a melt extrusion process, a solvent casting process, a wet coating process, and a lamination process. includes

The method for manufacturing a biodegradable article according to an embodiment of the present invention includes forming a biodegradable coating layer on at least one surface of a substrate through a coating process selected from the group consisting of a melt extrusion process, a solvent casting process, a wet coating process, and a lamination process. By including, since it is possible to effectively form an eco-friendly coating layer with excellent biodegradability and biocompatibility, it is possible to effectively manufacture a biodegradable article having excellent biodegradability, coating property, productivity and processability.

1 shows a biodegradable article according to an embodiment of the present invention.
Figure 2 shows a biodegradable article according to another embodiment of the present invention.
3 shows a biodegradable article according to another embodiment of the present invention.
4 shows a biodegradable article according to another embodiment of the present invention.

Hereinafter, the present invention will be described in detail. The present invention is not limited to the content disclosed below and may be modified in various forms as long as the gist of the invention is not changed.

In the present specification, when a part "includes" a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

All numbers and expressions indicating amounts of ingredients, reaction conditions, etc. described herein are to be understood as being modified by the term "about" in all cases unless otherwise specified.

In this specification, a component described as being formed above or below another component means that a component is formed directly above or below another component or indirectly through another component. include

In this specification, terms such as first, second, primary, secondary, etc. are used to describe various components, and the components are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

In this specification, the standards for "one side" / "other surface" or "upper" / "lower" of each component are described based on the drawings, and these terms are only terms for distinguishing the components, and actual application may be interchangeable.

In addition, the size of each component in the drawings may be exaggerated for explanation, and does not mean the size actually applied. Also, like reference numerals refer to like elements throughout.

Method for manufacturing biodegradable article

The method for manufacturing a biodegradable article according to an embodiment of the present invention includes forming a biodegradable coating layer on at least one surface of a substrate through a coating process selected from the group consisting of a melt extrusion process, a solvent casting process, a wet coating process, and a lamination process. includes

The substrate is not limited as long as it is an article capable of forming a biodegradable coating layer on the surface of the substrate. For example, the substrate is paper, kraft paper, fabric, nonwoven fabric, polyethylene terephthalate (PET) film, polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene adipate terephthalate ( PBAT), a polyester-based film such as polybutylene succinate terephthalate (PBST), a polypropylene (PP) film, a polyethylene (PE) film, and a polyimide (PI) film may be at least one selected from the group consisting of.

Specifically, the substrate may be preferably a single material substrate in terms of improving the coatability of the substrate, and the substrate may be paper, kraft paper, woven or non-woven fabric, but is not limited thereto. In addition, when the substrate includes paper or kraft paper, it may be more advantageous in providing an eco-friendly packaging material because it has superior biodegradability than other plastic materials.

The thickness of the substrate may be 20 μm or more. For example, the thickness of the substrate may be 20 μm or more, 50 μm or more, 70 μm or more, 100 μm or more, 130 μm or more, 150 μm or more, 200 μm or more, 300 μm or more, or 500 μm or more.

In addition, the basis weight of the substrate may be 30 g/m ² to 500 g/m ² . For example, when the substrate is paper, kraft paper, woven fabric, knitted fabric or nonwoven fabric, the basis weight of the substrate is 30 g/m ² to 500 g/m ² , 30 g/m ² to 350 g/m ² , 30 g/m ² to 200 g/m ² , 50 g/m ² to 200 g/m ² , 80 g/m ² to 200 g/m ² , 100 g/m ² to 200 g/m ² , 130 g/ m ² to 190 g/m ² , 150 g/m ² to 185 g/m ² or 120 g/m ² to 320 g/m ² may be.

On the other hand, a barrier layer may be disposed on at least one surface of the substrate, and an eco-friendly blocking film is coated on the surface of the substrate to have barrier properties of moisture and/or oxygen, or a functional coating layer having antistatic performance or adhesive performance may include more. The functional coating layer may include a primer coating layer and an adhesive coating layer, which may have materials and properties commonly used as long as they do not impair the desired effect in the present invention.

biodegradable coating composition

Polyhydroxyalkanoate (PHA) resins are conventional petroleum-derived polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), polybutylene It has properties similar to synthetic polymers such as lensuccinate adipate (PBSA), and exhibits complete biodegradability and excellent biocompatibility.

Specifically, the PHA resin is a thermoplastic natural polyester polymer that accumulates in microbial cells. Since it is a biodegradable material, it can be composted and finally decomposed into carbon dioxide, water and organic waste without generating toxic waste. In particular, since the PHA resin can be biodegradable in soil and sea, when the biodegradable coating composition and a biodegradable article using the same include the PHA resin, it may have environmentally friendly properties. Accordingly, the biodegradable coating composition and the biodegradable article using the same have excellent biodegradability and are environmentally friendly, and thus have a great advantage in that they can be utilized in various fields.

The biodegradable coating composition according to an embodiment of the present invention may include polyhydroxyalkanoate (PHA) resin, thereby improving biodegradability without deterioration of mechanical properties.

The PHA resin may be formed by polymerizing one or more repeating monomer units in living cells using an enzyme catalyst.

The PHA resin may be a copolymerized polyhydroxyalkanoate resin (hereinafter referred to as a copolymerized PHA resin), and specifically may be a copolymer in which different repeating units are randomly distributed in a polymer chain.

Examples of the repeating unit that can be incorporated into the PHA resin include 2-hydroxybutyrate, lactic acid, glycolic acid, 3-hydroxybutyrate (hereinafter referred to as 3-HB), 3-hydroxypropionate (hereinafter referred to as 3-HB). , 3-HP), 3-hydroxyvalerate (hereinafter referred to as 3-HV), 3-hydroxyhexanoate (hereinafter referred to as 3-HH), 3-hydroxyheptano 8 (hereinafter referred to as 3-HHep), 3-hydroxyoctanoate (hereinafter referred to as 3-HO), 3-hydroxynonanoate (hereinafter referred to as 3-HN), 3- Hydroxydecanoate (hereinafter referred to as 3-HD), 3-hydroxydodecanoate (hereinafter referred to as 3-HDd), 4-hydroxybutyrate (hereinafter referred to as 4-HB), 4-hydroxyvalerate (hereinafter referred to as 4-HV), 5-hydroxyvalerate (hereinafter referred to as 5-HV) and 6-hydroxyhexanoate (hereinafter referred to as 6-HH) ), and the PHA resin may contain one or more repeating units selected from them.

Specifically, the PHA resin is 3-HB, 4-HB, 3-HP, 3-HH. It may include one or more repeating units selected from the group consisting of 3-HV, 4-HV, 5-HV and 6-HH.

More specifically, the PHA resin may include a 4-HB repeating unit. That is, the PHA resin may be a copolymerized PHA resin including a 4-HB repeating unit.

In addition, the PHA resin may include isomers. For example, the PHA resin may include structural isomers, enantiomers or geometric isomers. Specifically, the PHA resin may include structural isomers.

In addition, the PHA resin includes a 4-HB repeating unit, and further includes one repeating unit different from the 4-HB, or 2, 3, 4, 5, 6 or more different from each other. It may be a copolymerized PHA resin further comprising a repeating unit. For example, the PHA resin may be poly 3-hydroxybutyrate-co-4-hydroxybutyrate (hereinafter referred to as 3HB-co-4HB).

According to an embodiment of the present invention, it is important to control the content of the 4-HB repeating unit included in the copolymerized PHA resin.

Specifically, in order to implement the physical properties desired in the present invention, in particular, to enhance biodegradability in soil and sea, dispersibility, dispersion stability, storage stability, coating property, water resistance, processability, productivity, etc. without deterioration of mechanical properties It is very important to control the content of the 4-HB repeating unit included in the copolymerized PHA resin in order to realize excellent physical properties.

More specifically, the copolymerized PHA resin may include 0.1 to 60% by weight of the 4-HB repeating unit based on the total weight of the copolymerized PHA resin. For example, the content of the 4-HB repeating unit may be 0.1 wt% to 60 wt%, 0.1 to 55 wt%, 0.5 to 60 wt%, 0.5 to 55 wt%, 1 wt% based on the total weight of the copolymerized PHA resin % to 60 wt%, 1 wt% to 55 wt%, 1 wt% to 50 wt%, 2 wt% to 55 wt%, 3 wt% to 55 wt%, 3 wt% to 50 wt%, 5 wt% to 55 wt%, 5 wt% to 50 wt%, 10 wt% to 55 wt%, 10 wt% to 50 wt%, 1 wt% to 40 wt%, 1 wt% to 30 wt%, 1 wt% to 29 wt% % 1% to 25%, 1% to 24%, 2% to 20%, 2% to 23%, 3% to 20%, 3% to 15%, 4 wt% to 18 wt%, 5 wt% to 15 wt%, 8 wt% to 12 wt%, 9 wt% to 12 wt%, 15 wt% to 55 wt%, 15 wt% to 50 wt%, 20 wt% to 55 wt%, 20 wt% to 50 wt%, 25 wt% to 55 wt%, 25 wt% to 50 wt%, 35 wt% to 60 wt%, 40 wt% to 55 wt% or 45 wt% to 55 wt% % by weight.

When the content of 4-HB repeating unit satisfies the above range, biodegradability in soil and sea is enhanced, and properties such as dispersibility, dispersion stability, storage stability, coating property, oil resistance, processability and productivity without deterioration of mechanical properties can be further improved.

According to an embodiment of the present invention, the PHA resin may be a copolymerized PHA resin with controlled crystallinity. Specifically, the PHA resin may include at least one 4-HB repeating unit, and the crystallinity of the PHA resin may be controlled by controlling the content of the 4-HB repeating unit.

In addition, the PHA resin is 3-hydroxybutyrate (3-HB), 4-hydroxybutyrate (4-HB), 3-hydroxypropionate (3-HP), 3-hydroxyhexanoate (3 -HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV) and 6-hydroxyhexanoate (6- It may be a copolymerized polyhydroxyalkanoate (PHA) resin including at least one repeating unit selected from the group consisting of HH).

Specifically, the copolymerized PHA resin includes 4-HB repeating units, 3-HB repeating units, 3-HP repeating units, 3-HH repeating units, 3-HV repeating units, 4-HV repeating units, and 5-HV repeating units. It may further include one or more repeating units selected from the group consisting of repeating units and 6-HH repeating units. More specifically, the copolymerized PHA resin may include 4-HB repeating units and 3-HB repeating units.

For example, the copolymerized PHA resin may contain 20 wt% or more, 35 wt% or more, 40 wt% or more, or 50 wt% or more, 60 wt% or more, 70 wt% or more of 3-HB repeating unit based on the total weight of the copolymerized PHA resin It may be included in weight % or more or 75 wt% or more, 99 wt% or less, 98 wt% or less, 97 wt% or less, 96 wt% or less, 95 wt% or less, 93 wt% or less, 91 wt% or less, 90 wt% or less Weight % or less, 80 wt% or less, 70 wt% or less, 60 wt% or less, or 55 wt% or less may be included.

The crystallinity-controlled PHA resin may be one in which crystallinity and amorphous properties are controlled by increasing irregularities in molecular structure, and specifically, the type or ratio of monomers or the type or content of isomers may be adjusted.

According to an embodiment of the present invention, the PHA resin may include two or more kinds of PHA resins having different crystallinities. Specifically, the PHA resin may be prepared by mixing two or more PHA resins having different crystallinities to have the content of the 4-HB repeating unit in the specific range.

Specifically, the PHA resin may include a first PHA resin that is a semi-crystalline PHA resin.

The first PHA resin is a semi-crystalline PHA (hereinafter, referred to as scPHA) resin with controlled crystallinity, and may include a 4-HB repeating unit in an amount of 0.1 wt% to 30 wt%. For example, the first PHA resin may contain the 4-HB repeating unit at 0.1 wt% to 30 wt%, 0.5 wt% to 30 wt%, 1 wt% to 30 wt%, 3 wt% to 30 wt%, 1 wt% % to 28 wt%, 1 wt% to 25 wt%, 1 wt% to 24 wt%, 1 wt% to 15 wt%, 2 wt% to 25 wt%, 3 wt% to 25 wt%, 3 wt% to 24 wt%, 5 wt% to 24 wt%, 7 wt% to 20 wt%, 10 wt% to 20 wt%, 15 wt% to 25 wt% or 15 wt% to 24 wt% may be included.

The glass transition temperature (Tg) of the first PHA resin is -30°C to 80°C, -30°C to 10°C, -25°C to 5°C, -25°C to 0°C, -20°C to 0°C or -15 It may be ℃ to 0 ℃. The crystallization temperature (Tc) of the first PHA resin may be 70°C to 120°C, 75°C to 120°C, or 75°C to 115°C, and the melting temperature (Tm) is 105°C to 165°C, 110°C to 160°C. , 115°C to 155°C or 120°C to 150°C.

The weight average molecular weight of the first PHA resin is 10,000 g/mol to 1,200,000 g/mol, 50,000 g/mol to 1,100,000 g/mol 100,000 g/mol to 1,000,000 g/mol, 100,000 g/mol to 900,000 g/mol, 200,000 g/mol to 800,000 g/mol, 200,000 g/mol to 600,000 g/mol or 200,000 g/mol to 400,000 g/mol.

In addition, the PHA resin may include a second PHA resin, which is an amorphous PHA resin with controlled crystallinity.

The second PHA resin is an amorphous PHA (hereinafter referred to as aPHA) resin with controlled crystallinity, and contains 15 to 60% by weight, 15 to 55% by weight, 20 to 20% by weight of the 4-HB repeating unit. 55% by weight, 25% to 55% by weight, 30% to 55% by weight, 35% to 55% by weight, 20% to 50% by weight, 25% to 50% by weight, 30% to 50% by weight %, 35% to 50% by weight or 20% to 40% by weight.

The glass transition temperature (Tg) of the second PHA resin may be -45°C to -10°C, -35°C to -15°C, -35°C to -20°C, or -30°C to -20°C.

In addition, the crystallization temperature (Tc) of the second PHA may not be measured, or may be 60°C to 120°C, 60°C to 110°C, 70°C to 120°C, or 75°C to 115°C. The melting temperature (Tm) of the second PHA may not be measured, or may be 100°C to 170°C, 100°C to 160°C, 110°C to 160°C, or 120°C to 150°C.

The weight average molecular weight of the second PHA resin is 10,000 g/mol to 1,200,000 g/mol, 10,000 g/mol to 1,000,000 g/mol, 50,000 g/mol to 1,000,000 g/mol, 200,000 g/mol to 1,200,000 g/mol, 300,000 g/mol to 1,000,000 g/mol, 100,000 g/mol to 900,000 g/mol, 500,000 g/mol to 900,000 g/mol, 200,000 g/mol to 800,000 g/mol or 200,000 g/mol to 400,000 g/mol can

The first PHA resin and the second PHA resin may be distinguished according to the content of the 4-HB repeating unit, and the group consisting of the glass transition temperature (Tg), the crystallization temperature (Tc) and the melting temperature (Tm). It may have at least one characteristic selected from Specifically, the first PHA resin and the second PHA resin may be distinguished according to the content of the 4-HB repeating unit, the glass transition temperature (Tg), the crystallization temperature (Tg), the melting temperature (Tm), and the like.

According to an embodiment of the present invention, the PHA resin may include the first PHA resin or both the first PHA resin and the second PHA resin.

Specifically, since the PHA resin includes the first PHA resin that is a semi-crystalline PHA resin, or includes both the first PHA resin that is a semi-crystalline PHA resin and the second PHA resin that is an amorphous PHA resin, more specifically, the first PHA resin By controlling the content of the resin and the second PHA resin, dispersibility, dispersion stability, storage stability, coatability and processability may be further improved.

In addition, the glass transition temperature (Tg) of the PHA resin is -45 ℃ to 80 ℃, -35 ℃ to 80 ℃, -30 ℃ to 80 ℃, -25 ℃ to 75 ℃, -20 ℃ to 70 ℃, -35 °C to 5 °C, -25 °C to 5 °C, -35 °C to 0 °C, -25 °C to 0 °C, -30 °C to -10 °C, -35 °C to -15 °C, -35 °C to -20 °C, -20°C to 0°C, -15°C to 0°C or -15°C to -5°C.

The crystallization temperature (Tc) of the PHA resin is not measured, or is 60°C to 120°C, 60°C to 110°C, 70°C to 120°C, 75°C to 120°C, 75°C to 115°C, 75°C to 110°C or It may be 90 °C to 110 °C.

The melting temperature (Tm) of the PHA resin is not measured, or 100°C to 170°C, 105°C to 170°C, 105°C to 165°C, 110°C to 160°C, 115°C to 155°C, 110°C to 150°C, 120°C to 150°C or 120°C to 140°C.

In addition, the weight average molecular weight of the PHA resin may be 10,000 g/mol to 1,200,000 g/mol. For example, the weight average molecular weight of the PHA resin is 50,000 g/mol to 1,200,000 g/mol, 100,000 g/mol to 1,200,000 g/mol, 50,000 g/mol to 1,000,000 g/mol, 100,000 g/mol to 1,000,000 g/mol mol, 200,000 g/mol to 1,200,000 g/mol, 250,000 g/mol to 1,150,000 g/mol, 300,000 g/mol to 1,100,000 g/mol, 350,000 g/mol to 1,000,000 g/mol, 350,000 g/mol to 950,000 g/mol mol, 100,000 g/mol to 900,000 g/mol, 200,000 g/mol to 800,000 g/mol, 200,000 g/mol to 700,000 g/mol, 250,000 g/mol to 650,000 g/mol, 200,000 g/mol to 400,000 g/mol mol, 300,000 g/mol to 800,000 g/mol, 300,000 g/mol to 600,000 g/mol, 500,000 g/mol to 1,200,000 g/mol, 500,000 g/mol to 1,000,000 g/mol 550,000 g/mol to 1,050,000 g/mol , 550,000 g/mol to 900,000 g/mol, 600,000 g/mol to 900,000 g/mol or 500,000 g/mol to 900,000 g/mol.

The crystallinity of the PHA resin as measured by Differential Scanning Calorimeter (DSC) may be 90% or less. For example, the crystallinity of the PHA resin may be measured by differential scanning calorimetry, and may be 90% or less, 85% or less, 80% or less, 75% or less, or 70% or less.

The average particle size of the PHA resin may be less than 150 μm. For example, the average particle size of the PHA resin is less than 150 µm, 140 µm or less, 130 µm or less, 120 µm or less, 100 µm or less, 90 µm or less, 85 µm or less, 80 µm or less, 60 µm or less, 45 µm or less. or less, 30 μm or less, 10 μm or less, 5 μm or less, 3 μm or less, 0.1 μm or more to less than 150 μm, 0.1 μm to 130 μm, 0.1 μm to 100 μm, 0.1 μm to 85 μm, 0.2 μm to 70 μm, 0.3 μm to 50 μm, 0.5 μm to 35 μm, 0.7 μm to 25 μm, 1 μm to 15 μm, 1 μm to 10 μm, 1.2 μm to 8 μm, 1.2 μm to 6 μm, 1.5 μm to 4 μm or It may be 1.5 μm to 2.5 μm.

The polydispersity index (PDI) of the PHA resin may be less than 3. For example, the polydispersity index of the PHA resin may be less than 3, 2.9 or less, 2.7 or less, 2.65 or less, 2.5 or less, 2.3 or less, or 2 or less.

When the average particle size and polydispersity index of the PHA resin satisfy the above ranges, dispersibility, dispersion stability, storage stability, coatability, and processability can be further improved.

In addition, the PHA may be obtained by cell disruption using a mechanical method or a physical method, or may be obtained by cell disruption using a non-mechanical method or a chemical method. . Specifically, since the PHA is a thermoplastic natural polyester polymer that accumulates in microbial cells and has a relatively large average particle diameter, it may be obtained through a crushing process to improve dispersibility, coating property and processability.

For example, the PHA resin may be in particulate form. Specifically, the PHA resin obtained by disrupting cells using a mechanical method or a physical method, or by disrupting cells using a non-mechanical method or a chemical method may be a powder in the form of fine particles.

Alternatively, the PHA resin obtained by cell disruption using a mechanical or physical method may be in the form of a large average particle diameter such as granules or pellets.

In addition, the PHA resin may be obtained by cell disruption using at least one selected from the group consisting of ultrasonic crushing, high pressure crushing, and milling crushing.

The ultrasonic crushing may be performed for 10 to 60 minutes with an energy amount of 20 Hz or more. For example, the ultrasonic crushing may be performed for 10 minutes to 60 minutes, 15 minutes to 55 minutes, or 20 minutes to 50 minutes with an energy amount of 60 Hz or less, 50 Hz or less, or 40 Hz or less.

The high-pressure crushing may be performed for 1 minute to 60 minutes at a pressure of 10 bar or more. For example, the high-pressure crushing may be performed for 1 minute to 60 minutes, 2 minutes to 60 minutes, or 3 minutes to 60 minutes at a pressure of 10 bar or more, 20 bar or more, or 50 bar or more.

The milling crushing is performed with one or more selected from the group consisting of a colloid mill, a bead mill and a ball mill for 1 minute to 60 minutes, 2 minutes to 60 minutes, or 3 minutes to 60 minutes. can be performed.

The solids content of the biodegradable coating composition may be 10% by weight to 60% by weight. For example, the solids content of the biodegradable coating composition is 10 wt% to 60 wt%, 15 wt% to 55 wt%, 20 wt% to 55 wt%, 25 wt% to 50 wt%, 30 wt% to 45 wt% % by weight or between 35% and 45% by weight.

According to another embodiment of the present invention, the biodegradable coating composition may further include a biodegradable polymer.

Specifically, the biodegradable polymer is polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), thermoplastic starch (TPS), polybutylene succinate terephthalate (PBST) , polyethylene terephthalate (PET), polybutylene succinate adipate (PBSA), polybutylene adipate (PBA), polypropylene (PP), polyethylene (PE) and polycaprolactone (PCL) selected from the group consisting of It may include one or more types. By further including the biodegradable polymer, the biodegradable coating composition may be more advantageous in controlling properties such as mechanical properties.

In addition, the biodegradable coating composition may include 10 wt% to 70 wt% of the PHA resin based on the total weight of the biodegradable coating composition on a solids basis. For example, the content of the PHA resin may be 10 wt% to 70 wt%, 20 wt% to 65 wt%, 25 wt% to 55 wt%, 30 wt% to 45 wt% based on the total weight of the biodegradable coating composition on a solids basis % by weight or between 35% and 40% by weight.

In addition, the biodegradable coating composition may further include at least one additive selected from the group consisting of a surfactant, a rheology control agent, a crosslinking agent, an antioxidant, a stabilizer, and a pH control agent.

The surfactant may be at least one selected from the group consisting of cationic surfactants, anionic surfactants, phosphoric acid surfactants, fatty acid surfactants, acrylic surfactants, urethane surfactants, epoxy surfactants, and nonionic surfactants. and may be a polymer surfactant comprising at least one selected from the group consisting of carboxylic acids, amines, isocyanates, and derivatives thereof.

By including the surfactant in the biodegradable coating composition, dispersibility, dispersion stability, storage stability, coatability and processability may be further improved.

For example, the surfactant may include polyvinyl alcohol, sodium dodecylbenzene sulfonate, polyvinyl pyrrolidone, methyl polyethylene alkyl ether, alkylbenzene sulfonate, nonylphenol ether sulfate, sodium lauryl sulfate, lithium dodecyl sulfate, It may be at least one selected from the group consisting of alkyl phosphates, glyceryl esters and polypropylene glycol esters.

In addition, the biodegradable coating composition may include 0.01 wt% to 30 wt% of the surfactant relative to the total weight of the biodegradable coating composition on a solids basis. For example, the content of the surfactant may be 0.01 wt% to 30 wt%, 0.05 wt% to 25 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 15 wt% based on the total weight of the biodegradable coating composition on a solid basis wt%, 0.1 wt% to 10 wt%, 0.1 wt% to 5 wt%, 0.01 wt% to 5 wt%, 0.05 wt% to 4 wt%, 0.1 wt% to 5 wt%, 1 wt% to 5 wt% , 1.5 wt% to 5 wt%, 0.1 wt% to 3 wt%, or 0.1 wt% to 2.8 wt%.

The biodegradable coating composition has excellent dispersibility, dispersion stability, storage stability, coatability and processability despite including a small amount of surfactant compared to the prior art.

The rheology control agent may be at least one selected from the group consisting of gums, clay minerals, cellulose derivatives, cellulose-based regulators, acrylic-based regulators, and urethane-based regulators. For example, the rheology modifier may be one type of gum, a clay mineral, or a cellulosic modifier, or a mixture of two such as gum and a clay mineral or a gum and a cellulosic modifier.

The biodegradable coating composition may further improve coatability, processability and productivity by including a rheology control agent.

The rheology control agent may be at least one selected from the group consisting of gums, clay minerals, cellulose derivatives, cellulose-based regulators, acrylic-based regulators, and urethane-based regulators. For example, the rheology modifier may be one type of gum, a clay mineral, or a cellulosic modifier, or a mixture of two such as gum and a clay mineral or a gum and a cellulosic modifier.

The gum may be at least one selected from the group consisting of xanthan gum, guar gum, gellan gum, locust gum, xanthan gum, gum arabic, carrageenan, karaya gum, ghati gum, tara gum, tamarind gum and tragacanth gum. . The clay mineral may be at least one selected from the group consisting of bentonite, smectite, eterpulgite, montmorillonite, kaolinite, sericite, and illite.

The cellulose derivative may be at least one selected from the group consisting of casein, sodium caseinate and sodium alginate. The cellulose-based regulator may be at least one selected from the group consisting of methyl cellulose, hydroxypropyl cellulose and methyl hydroxypropyl cellulose.

In addition, the rheology modifier may have a branched, straight, plate, irregular, spherical or rod-shaped shape. By having the rheology control agent as described above, it is possible to further improve coating properties, processability and productivity.

The rheology modifier is 0.01 wt% to 20 wt%, 0.01 wt% to 15 wt%, 0.01 wt% to 12 wt%, 0.01 wt% to 10 wt%, 0.01 to the total weight of the biodegradable coating composition on a solids basis wt% to 8 wt%, 0.01 wt% to 5 wt%, 0.01 wt% to 4 wt%, 0.01 wt% to 3 wt%, 0.02 wt% to 2 wt%, 0.02 wt% to 1.5 wt% or 0.03 wt% to 1% by weight.

The antioxidant is an additive to prevent decomposition by ozone or oxygen, or to prevent oxidation during storage, and to prevent deterioration of physical properties. As long as the effect of the present invention is not impaired, commonly used antioxidants can be used.

Specifically, the antioxidant may include at least one selected from the group consisting of a hindered phenol-based antioxidant and a phosphite-based (phosphorus) antioxidant.

For example, the hindered phenolic antioxidant is 4,4'-methylene-bis(2,6-di-t-butylphenol), octadecyl-3-(3,5-di-t-butyl-4) -hydroxyphenyl)propionate, pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate) and 3,9-bis[2-[3- from the group consisting of (3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane It may include at least one selected type.

In addition, the phosphite-based (phosphorus-based) antioxidant is tris-(2,4-di-t-butylphenyl)phosphite, bis-(2,4-di-t-butylphenyl)pentaerythritol-diphosphite, Bis-(2,6-di-t-butyl-4-methylphenyl)pentaerythritol-diphosphite, distearyl-pentaerythritol-diphosphite, [bis(2,4-di-t-butyl-5- Methylphenoxy)phosphino]biphenyl and N,N-bis[2-[[2,4,8,10-tetrakis(1,1-dimethylethyl)dibenzo[d,f][1,3, 2] It may include at least one selected from the group consisting of deoxyphosphepin-6-yl]oxy]-ethyl]ethanamine.

The antioxidant is 0.01 wt% to 20 wt%, 0.01 wt% to 15 wt%, 0.01 wt% to 12 wt%, 0.01 wt% to 10 wt%, 0.01 wt% based on the total weight of the biodegradable coating composition on a solids basis % to 8 wt%, 0.01 wt% to 5 wt%, 0.2 wt% to 4.5 wt%, 0.2 wt% to 4 wt% or 0.5 wt% to 3 wt%.

The stabilizer is an additive to protect from oxidation and heat, and to prevent color change. As long as the stabilizer does not impair the effects of the present invention, a commonly used stabilizer may be used.

Specifically, the stabilizer may be at least one selected from the group consisting of trimethyl phosphate, triphenyl phosphate, trimethyl phosphine, phosphoric acid and phosphorous acid.

The stabilizer is 0.01 wt% to 20 wt%, 0.01 wt% to 15 wt%, 0.01 wt% to 12 wt%, 0.01 wt% to 10 wt%, 0.01 wt% based on the total weight of the biodegradable coating composition on a solids basis % to 8 wt%, 0.01 wt% to 5 wt%, 0.2 wt% to 4.5 wt%, 0.2 wt% to 4 wt% or 0.5 wt% to 3 wt%.

The antibacterial agent may be at least one natural antibacterial agent selected from the group consisting of organic acids, bacteriocins and calcium agents or a compound containing an element such as colloid or silver, polylysine, benzisothiazolinone, vinegar powder, chitooligosaccharide, hydrogen peroxide, It may be at least one selected from the group consisting of ethylenediaminetetraacetic acid, potassium sorbate, sorbic acid, propionic acid, potassium propionate, sodium benzoate, 1,2-hexanediol, and 1,2-octanediol.

The antimicrobial agent is 0.01 wt% to 5 wt%, 0.01 wt% to 3 wt%, 0.01 wt% to 1 wt%, 0.1 wt% to 1 wt%, 0.2 wt% based on the total weight of the biodegradable coating composition on a solids basis to 1% by weight or 0.3% to 1% by weight.

In addition, the antifoaming agent is an additive for preventing or reducing foaming. As long as the anti-foaming agent does not impair the effects of the present invention, a conventionally used anti-foaming agent may be used.

For example, the anti-foaming agent may be at least one selected from the group consisting of alcohol-based anti-foaming agents, polar compound-based anti-foaming agents, inorganic particle-based anti-foaming agents and silicone-based anti-foaming agents, ethyl alcohol, 2-ethylhexanol, polysiloxane, dimethyl polysiloxane, silicone paste , silicone emulsion, silicone treatment powder, fluorosilicone, distearic acid, ethylene glycol, and may be at least one selected from the group consisting of natural wax.

The antifoaming agent is 0.0001 wt% to 5 wt%, 0.0001 wt% to 3 wt%, 0.0001 wt% to 1 wt%, 0.001 wt% to 1 wt% or 0.001 wt% based on the solids content of the biodegradable coating composition to 0.5% by weight.

In addition, the preservative is at least one natural selected from the group consisting of hydroxyacetophenone, centella asiatica extract, 1,2-hexanediol and 1,3-butanediol extracted from camprina oak tree. It may be a preservative, and may be at least one preservative selected from the group consisting of benzisothiazolin-3-one and potassium benzoate, but is not limited thereto.

The preservative is 0.01% to 20% by weight, 0.01% to 15% by weight, 0.01% to 12% by weight, 0.01% to 10% by weight, 0.01% by weight based on the total weight of the biodegradable coating composition on a solids basis to 8 wt%, 0.01 wt% to 5 wt%, 0.2 wt% to 4.5 wt%, 0.2 wt% to 4 wt% or 0.5 wt% to 3 wt%.

In addition, the pH adjusting agent refers to a material that is added to a solution to adjust the pH, and may include both a pH reducing agent for decreasing pH and a pH increasing agent for increasing pH. Specifically, the pH reducing agent may be a strong acid material such as sulfuric acid or hydrochloric acid, or an aqueous ammonium salt solution, and the pH increasing agent may be a basic material such as aqueous ammonia, sodium hydroxide, lithium hydroxide, potassium hydroxide, or the like, or an aqueous acetate salt solution. , but is not limited thereto.

For example, the pH increasing agent may be at least one selected from the group consisting of acetic acid, lactic acid, hydrochloric acid, phosphoric acid, sodium hydroxide, citric acid, malic acid, fumaric acid, potassium phosphate, sodium hydrogen carbonate and sodium phosphate.

The pH adjuster is 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight or 0.5 to 3% by weight may be included.

The acidity of the biodegradable coating composition may be 3 to 11. For example, the acidity of the biodegradable coating composition may be 3 to 11, 4 to 10, or 4 to 9.

melt extrusion process

According to another embodiment of the present invention, the step of forming the biodegradable coating layer may be performed through a melt extrusion process.

The biodegradable coating layer may be formed from a biodegradable coating composition, and the description of the biodegradable coating composition is as described above.

Alternatively, the biodegradable coating layer may be formed by melt-extruding and cooling a PHA resin, specifically PHA pellets or PHA granules, to form a biodegradable coating layer.

Specifically, the melt extrusion process may include a melt extrusion step and a cooling step. More specifically, it is possible to prepare a biodegradable article having a biodegradable coating layer formed on one surface of the substrate by melt co-extrusion using an extruder with the coating layer formed from the biodegradable coating composition in contact with one surface of the substrate.

The melt extrusion step may be performed at 120 °C to 180 °C. For example, the melt extrusion step may be performed at 120 °C to 180 °C, 125 °C to 175 °C, 130 °C to 170 °C, 135 °C to 165 °C or 140 °C to 160 °C.

In addition, when the melt extrusion step is performed by melt co-extrusion, the temperature at the time of melt co-extrusion of the substrate and the biodegradable coating composition may be different from each other.

The cooling step may be performed at 0 °C to 40 °C. For example, the cooling step may be performed at 3 °C to 40 °C, 5 °C to 35 °C, 5 °C to 30 °C, 5 °C to 25 °C, or 10 °C to 15 °C.

In addition, the cooling step may include a primary cooling step and a secondary cooling step. Specifically, the cooling step may be performed through a cooling roll, but is not limited thereto. For example, the primary cooling step may have a higher temperature than the secondary cooling step, the primary cooling step may be 25°C to 40°C or 25°C to 35°C, and the secondary cooling step is 3 It may be ℃ to 25 ℃, 5 ℃ to 23 ℃, 10 ℃ to 20 ℃ or 10 ℃ to 15 ℃.

The thickness of the biodegradable coating layer prepared by the melt extrusion process is 1 μm to 50 μm, 1 μm to 35 μm, 1.5 μm to 25 μm, 2 μm to 15 μm, 2 μm to 10 μm, 3 μm to 8 μm, 2 μm to 40 μm or 3 μm to 30 μm.

Solvent Casting Process

According to another embodiment of the present invention, forming the biodegradable coating layer may be performed through a solvent casting process.

Specifically, the solvent casting process comprises the steps of: preparing a biodegradable coating solution by dissolving a polyhydroxyalkanoate (PHA) resin in a solvent; applying the biodegradable coating solution on a substrate; and drying.

The description of the PHA resin is the same as described above.

The solvent is chloroform, ethyl acetate, butyl acetate, isobutyl acetate, amyl acetate, isoamyl acetate, isobutyl alcohol, 1-butanol, 1-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol , 3-pentanol, 1-hexanol, cyclohexanol, propyl propionate, butyl propionate, isobutyl propionate, ethyl butyrate, isobutyl isobutyrate, dichloromethane, N,N-dimethylformamide, It may be at least one selected from the group consisting of dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, methylethylketone, methylene chloride, tetrahydrofuran, toluene and acetone.

In addition, the biodegradable coating solution may include 50 wt% to 99 wt% of the solvent based on the total weight of the biodegradable coating solution. For example, the content of the solvent may be 50 wt% to 99 wt%, 60 wt% to 95 wt% to 70 wt% to 90 wt% based on the total weight of the biodegradable coating solution.

The viscosity of the biodegradable coating solution may be 100 cps to 100,000 cps. For example, the viscosity of the biodegradable coating solution is 100 cps to 100,000 cps, 120 cps to 90,000 cps, 150 cps to 80,000 cps, 150 cps to 50,000 cps, 150 cps to 30,000 cps, 150 cps to 10,000 cps, 100 cps to 8,000 cps, 100 cps to 5,000 cps, 100 cps to 3,000 cps, 100 cps to 1,500 cps, 150 cps to 1,000 cps.

The biodegradable coating solution preparation step may further include a stirring step. Specifically, the stirring step is performed using a homogenizer at a rate of 60% to 80%, 65% to 75%, or 60% to 70% of the maximum rotational speed per minute (rpm) for 20 minutes to 60 minutes, 25 It may be carried out by stirring treatment for minutes to 55 minutes, 25 minutes to 45 minutes, or 25 minutes to 40 minutes.

In addition, the application step is spin coating (spin coating), dip coating (dip coating), roll coating (roll coating), screen coating (screen coating), spray coating (spray coating), spin casting (spin casting), flow coating (flow coating), screen printing (screen printing), ink jet (ink jet), and may be performed by at least one method selected from the group consisting of drop casting (drop casting).

The application step may be performed at an application amount of 1 g/m ² to 50 g/m ^{2 .} For example, the application amount is 1 g/m ² to 50 g/m ² , 2 g/m ² to 40 g/m ² , 3 g/m ² to 30 g/m ² or 4 g/m ² to 20 It may be carried out with an application amount of g/m ^{2 .} When the coating amount satisfies the above range, coatability, productivity, and workability can be further improved.

In addition, the drying step may be performed for 10 seconds to 10 minutes at 25 ℃ to 200 ℃ by hot air drying. For example, the drying step may be performed by hot air drying at 25°C to 200°C, 25°C to 150°C, 25°C to 100°C, 50°C to 200°C, 80°C to 200°C, 100°C to 200°C or 125°C to 10 seconds to 10 minutes, 20 seconds to 8 minutes, 30 seconds to 6 minutes, 1 minute to 6 minutes, 2 minutes to 5 minutes, 10 seconds to 5 minutes, 10 seconds to 3 minutes or 20 seconds to 1 minute at 200°C can be performed while

The thickness of the biodegradable coating layer prepared by the solvent casting process is 1 μm to 50 μm, 1 μm to 35 μm, 1.5 μm to 25 μm, 2 μm to 15 μm, 3 μm to 45 μm, 5 μm to 30 μm, 8 μm to 20 μm, 8 μm to 12 μm, 2 μm to 40 μm, or 3 μm to 30 μm.

wet coating process

According to another embodiment of the present invention, the step of forming the biodegradable coating layer may be performed through a wet coating process.

Specifically, the wet coating process comprises the steps of preparing a dispersion comprising a biodegradable coating composition; applying the dispersion on a substrate; and drying.

First, the dispersion preparation step may include mixing and stirring the PHA resin and the surfactant. The description of the PHA and the surfactant is the same as described above.

Specifically, a dispersion including the biodegradable coating composition may be prepared by stirring a mixture of the PHA resin and the surfactant.

The stirring step is performed using a homogenizer at a rate of 60% to 80%, 65% to 75%, or 60% to 70% of the maximum rotational speed per minute (rpm) for 20 minutes to 60 minutes, 25 minutes to 55 minutes. minutes, 25 to 45 minutes or 25 to 40 minutes.

In addition, the stirring step may be performed at 6,000 rpm to 10,000 rpm for 15 minutes to 60 minutes. For example, the stirring step may be performed by centrifugation, an agitator or a homogenizer, 6,000 rpm to 10,000 rpm, 6,500 rpm to 9,500 rpm, 7,000 rpm to 9,000 rpm, or 7,500 rpm to 8,500 rpm 15 minutes to 60 minutes, 20 minutes to 50 minutes, 20 minutes to 40 minutes or 25 minutes to 35 minutes.

In addition, before mixing the PHA resin and the surfactant, a step of stirring the PHA resin may be additionally performed.

Specifically, a primary aqueous dispersion may be prepared by stirring the PHA resin. The stirring may be performed at 1,000 rpm to 6,000 rpm for 5 minutes to 150 minutes. For example, the stirring may be performed using a stirrer (product name: homo-disper, manufacturer: premix, maximum rotational speed per minute: 8,000 rpm) utilizing uniaxial shear stress, 1,000 rpm to 6,000 rpm , 1,000 rpm to 5,000 rpm, 1,200 rpm to 4,500 rpm, 1,500 rpm to 4,000 rpm, 2,000 rpm to 6,000 rpm, 2,500 rpm to 5,500 rpm 5 minutes to 150 minutes, 20 minutes to 130 minutes, 25 minutes to 110 minutes, 30 minutes to 100 minutes, 60 minutes to 120 minutes, 70 minutes to 140 minutes, 5 minutes to 70 minutes, 10 minutes to 60 minutes, 20 minutes to 80 minutes, or 30 minutes to 60 minutes.

In addition, the stirring may be performed in a solvent.

Specifically, the solvent used in the stirring may be water, distilled water, or a hydrophilic solvent. Specifically, the solvent may be water, distilled water, or a hydrophilic solvent, or a mixture of water or distilled water and a hydrophilic solvent. For example, the hydrophilic solvent is methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol It may be at least one selected from the group consisting of alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol.

The solid content of the first aqueous dispersion may be 10 wt% to 60 wt%. For example, the solids content of the first aqueous dispersion may be 10 wt% to 60 wt%, 15 wt% to 55 wt%, 20 wt% to 55 wt%, 25 wt% to 50 wt%, 30 wt% to 45 wt% % by weight or between 35% and 45% by weight.

Thereafter, an additive may be added to the first aqueous dispersion and stirred to prepare a dispersion. The description of the additive and the stirring is the same as described above.

The viscosity of the dispersion may be 100 cps to 1,000 cps. For example, the viscosity of the dispersion may be 110 cps to 900 cps, 120 cps to 800 cps, or 130 cps to 700 cps.

In addition, the coating step is one selected from the group consisting of gravure coating, microgravure coating, capillary coating, slit coating, and bar coating. It can be performed in the above method.

In addition, the drying step may be performed for 10 seconds to 10 minutes at 100 ℃ to 200 ℃ by hot air drying. For example, the drying step is a hot air drying at 100°C to 200°C, 120°C to 180°C, 135°C to 170°C, 140°C to 165°C or 145°C to 155°C for 10 seconds to 10 minutes, 30 seconds to 8 minutes, 20 seconds to 6 minutes, 1 minute to 10 minutes, 2 minutes to 6 minutes, or 5 minutes to 10 minutes.

Alternatively, the drying step may be performed for 10 seconds to 10 minutes using infrared rays having a wavelength of 700 nm to 2,500 nm or ultraviolet rays having a wavelength of 200 nm to 400 nm. For example, the drying step is 700 nm to 2,500 nm, 700 nm to 1,500 nm, 800 nm to 1,200 nm, 1,200 nm to 2,500 nm, 1,500 nm to 2,200 nm infrared or 200 nm to 400 nm, 250 nm to 400 nm Using ultraviolet rays of nm or 250 nm to 350 nm for 10 seconds to 10 minutes, 30 seconds to 5 minutes, 20 seconds to 3 minutes, 1 minute to 3 minutes, 2 minutes to 5 minutes, 3 minutes to 10 minutes, 5 minutes to 10 minutes or from 10 seconds to 1 minute.

The thickness of the biodegradable coating layer prepared by the wet coating process is 1 μm to 50 μm, 1 μm to 35 μm, 1.5 μm to 25 μm, 2 μm to 15 μm, 3 μm to 45 μm, 5 μm to 30 μm, 8 μm to 20 μm, 2 μm to 40 μm, or 3 μm to 30 μm.

lamination process

According to another embodiment of the present invention, the step of forming the biodegradable coating layer may be performed through a lamination process.

Specifically, the lamination process may include laminating a biodegradable film on a substrate.

The biodegradable film is a biodegradable coating composition containing a polyhydroxyalkanoate (PHA) resin melt extrusion process (extrusioion molding), T-die process (T-die), calendar process (calendaring) and stretching process It may be prepared through one or more methods selected from the group consisting of.

For example, the biodegradable film is a biodegradable coating composition comprising a PHA resin is melted at 120 ° C to 180 ° C, 125 ° C to 175 ° C, 130 ° C to 170 ° C, 135 ° C to 165 ° C or 140 ° C to 160 ° C It may be manufactured by extrusion.

The description of the PHA resin is the same as described above.

Specifically, the method for preparing the biodegradable coating composition may include mixing and stirring a PHA resin and a surfactant. More specifically, a primary aqueous dispersion can be prepared by stirring a mixture of PHA resin and surfactant.

The description of the surfactant is the same as described above.

In the mixing step, a solvent may be additionally added. Specifically, a primary aqueous dispersion may be prepared by stirring a mixture of the PHA resin, surfactant, and solvent.

The solvent that may be additionally added in the mixing step may be water, distilled water, or a hydrophilic solvent. Specifically, the solvent may be water, distilled water, or a hydrophilic solvent, or a mixture of water or distilled water and a hydrophilic solvent. For example, the hydrophilic solvent is methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol It may be at least one selected from the group consisting of alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol.

In addition, the stirring step is performed using a homogenizer at a rate of 60% to 80%, 65% to 75%, or 60% to 70% of the maximum rotational speed per minute (rpm) for 20 minutes to 60 minutes, 25 minutes to 55 minutes, 25 to 45 minutes or 25 to 40 minutes.

In addition, the stirring step may be performed for 15 minutes to 60 minutes at 1,000 rpm to 10,000 rpm. For example, the stirring step may be performed by centrifugation, an agitator or a homogenizer, 1,000 rpm to 10,000 rpm, 2,000 rpm to 8,000 rpm, 2,500 rpm to 6,500 rpm, 2,500 rpm to 5,000 rpm , 6,000 rpm to 10,000 rpm, 6,500 rpm to 9,500 rpm, 7,000 rpm to 9,000 rpm or 7,500 rpm to 8,500 rpm for 15 minutes to 60 minutes, 20 minutes to 50 minutes, 20 minutes to 40 minutes or 25 minutes to 35 minutes can be

The solid content of the first aqueous dispersion may be 10 wt% to 60 wt%. For example, the solids content of the first aqueous dispersion may be 10 wt% to 60 wt%, 15 wt% to 55 wt%, 20 wt% to 55 wt%, 25 wt% to 50 wt%, 30 wt% to 45 wt% % by weight or between 35% and 45% by weight.

Thereafter, the first aqueous dispersion may be filtered, washed and redispersed to prepare a biodegradable coating composition.

The filtration step may be performed using a filter medium such as paper, woven fabric, nonwoven fabric, screen, polymer membrane or wedge wire, and may be a suction filter, a pressure filter, a membrane separator, a vacuum filter, a vacuum filter, an industrial filter press, a tube press. , a plate press, a gauge press, a belt press, a screw press, a disc press, a pressing function press or a centrifuge.

The washing step may be performed using a solvent. Specifically, the solvent used in the washing step may be water, distilled water, or a hydrophilic solvent, or a mixture of water or distilled water and a hydrophilic solvent. For example, the hydrophilic solvent is methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol It may be at least one selected from the group consisting of alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol.

The redispersion may be performed at 1,000 rpm to 10,000 rpm for 15 minutes to 60 minutes. For example, the redispersion may be performed by centrifugation, an agitator or a homogenizer, 1,000 rpm to 10,000 rpm, 2,000 rpm to 8,000 rpm, 2,500 rpm to 6,500 rpm, 2,500 rpm to 5,000 rpm , 6,000 rpm to 10,000 rpm, 6,500 rpm to 9,500 rpm, 7,000 rpm to 9,000 rpm or 7,500 rpm to 8,500 rpm for 15 minutes to 60 minutes, 20 minutes to 50 minutes, 20 minutes to 40 minutes or 25 minutes to 35 minutes can be

Before the redispersion step, a solvent may be additionally added. The solvent that may be additionally added before the redispersion step may be the same as the solvent used in the washing step.

The thickness of the biodegradable film is 1 μm to 100 μm, 5 μm to 80 μm, 10 μm to 65 μm, 20 μm to 60 μm, 30 μm to 55 μm, 40 μm to 100 μm, 45 μm to 85 μm, 1 μm to 60 μm, 5 μm to 55 μm, or 15 μm to 50 μm.

The paper is disposed so that the biodegradable film is in contact with the substrate, and at 120° C. to 200° C., 150° C. to 180° C. or 160° C. to 200° C. for 10 seconds to 10 minutes, 20 seconds to 5 minutes, 30 seconds to Lamination may be performed by applying heat for 3 minutes or 40 seconds to 2 minutes.

Alternatively, the lamination may be performed through an adhesive layer.

Specifically, the lamination process may be an adhesive lamination process. Specifically, the adhesive lamination process may be performed using an adhesive or an adhesive layer, and the adhesive may be a water-based adhesive, a water-dispersed adhesive, a hot-melt adhesive, or the like, but is not limited thereto.

The adhesive layer may include at least one selected from the group consisting of polyhydroxyalkanoate (PHA), polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), an acrylic resin, and a urethane-based resin.

Specifically, the adhesive layer is a polyhydroxyalkanoate (PHA) resin, polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), from an adhesive composition comprising at least one selected from the group consisting of an acrylic resin and a urethane-based resin can be formed.

For example, the adhesive composition may be prepared by mixing and stirring polyhydroxyalkanoate (PHA) resin, polyvinyl alcohol (PVA), and ethylene vinyl acetate (EVA).

In addition, the adhesive composition may include the PHA resin in an amount of 40 wt% or more based on the total weight of the adhesive composition. For example, the content of the PHA resin may be 40 wt% or more, 45 wt% or more, 50 wt% or more, 55 wt% or more, 65 wt% or more, 90 wt% or more, or 95 wt% or more based on the total weight of the adhesive composition. % or more.

The adhesive composition may include 0.01 wt% to 30 wt% of the polyvinyl alcohol (PVA) based on the total weight of the adhesive composition. For example, the content of the polyvinyl alcohol (PVA) is 0.01 wt% to 30 wt%, 0.05 wt% to 25 wt%, 0.05 wt% to 20 wt%, 0.1 wt% to 0.1 wt% based on the total weight of the adhesive composition 30 wt%, 0.1 wt% to 10 wt%, 0.1 wt% to 5 wt%, 0.01 wt% to 5 wt%, 0.05 wt% to 4 wt%, 0.1 wt% to 3 wt% or 0.1 wt% to 2.8 wt% It can be %.

The description of the stirring step is the same as described above.

Specifically, in the lamination process, an adhesive layer is formed on at least one surface of the biodegradable film formed from the biodegradable coating composition, and the biodegradable film on which the adhesive layer is formed is laminated on a substrate to manufacture a biodegradable article.

More specifically, the step of forming the adhesive layer includes spin coating, gravure coating, microgravure coating, capillary coating, slit coating, and a bar. After applying the adhesive composition by at least one method selected from the group consisting of coating (bar coating), it may be carried out by drying.

The description of the drying step is the same as described above.

biodegradable products

A biodegradable article according to another embodiment of the present invention includes a substrate; and a biodegradable coating layer on at least one surface of the substrate.

Figure 1 shows a biodegradable article according to an embodiment of the present invention, Figure 2 shows a biodegradable article according to another embodiment of the present invention.

Specifically, FIG. 1 illustrates a biodegradable article 1 having a biodegradable coating layer 200 formed on one side of the substrate 100 , and FIG. 2 is a biodegradable coating layer 200 formed on both sides of the substrate 100 . A biodegradable article (1) is illustrated.

In addition, Figure 3 shows a biodegradable article according to another embodiment of the present invention, Figure 4 shows a biodegradable article according to another embodiment of the present invention.

Specifically, FIG. 3 shows a structure in which an adhesive layer 300 is formed on a substrate 100, a biodegradable coating layer 200 is formed on the adhesive layer, and a substrate, an adhesive layer, and a biodegradable coating layer are sequentially stacked. Biodegradability The item is exemplified.

4 shows that the adhesive layer 300 is formed on both sides of the substrate 100, and the biodegradable coating layer 200 is respectively formed on the other surface of the adhesive layer, so that the biodegradable coating layer, the adhesive layer, the substrate, the adhesive layer and the biodegradable coating layer are sequentially formed. A biodegradable article with a laminated structure is illustrated.

By including a biodegradable coating layer on one or both surfaces of the substrate, the biodegradable article may have excellent biodegradability and biocompatibility, thereby being environmentally friendly and having excellent dispersibility, coatability, productivity and processability.

The description of the description is the same as described above.

The biodegradable article including the biodegradable coating layer may be a packaging material, a corrugated cardboard box, a shopping bag, disposable tableware, a packaging container, or a paper straw, but is not limited thereto.

The above will be described in more detail with reference to the following examples. However, the following examples are only for illustrating the present invention, and the scope of the examples is not limited thereto.

[Example]

Manufacture of biodegradable articles

<Melt extrusion process>

Example 1

Content of polyhydroxyalkanoate (PHA) (4-hydroxybutyrate (4-HB): 10% by weight, weight average molecular weight (Mw): 800,000 g/mol, polydispersity index (PDI): 2.0, manufacturer: CJ) pellets were prepared. The PHA pellets were obtained by physical crushing using a homogenizer (product name: homomixer mark2, manufacturer: primix).

The biodegradable coating layer containing the PHA pellets was disposed on one side of the substrate to be in contact, and melt co-extrusion was performed using an extruder. The temperature of the substrate and the biodegradable coating layer during the melt co-extrusion were set to 120°C and 150°C, respectively. At this time, the base material was uncoated and kraft paper (manufacturer: Hansol Paper) having a basis weight of ^{180 g/m 2 was used.}

Thereafter, a biodegradable article (thickness of the coating layer: 3 μm) was prepared by first cooling at 35° C. and secondary cooling at 15° C.

<Solvent Casting Process>

Example 2

(1) Preparation of biodegradable coating composition

Content of polyhydroxyalkanoate (PHA) (4-hydroxybutyrate (4-HB): 10% by weight, weight average molecular weight (Mw): 800,000 g/mol, polydispersity index (PDI): 2.0, manufacturer: CJ) powder was prepared. The PHA powder was obtained by physical crushing using a homogenizer (product name: homomixer mark2, manufacturer: primix).

10 parts by weight of the PHA powder and 90 parts by weight of a chloroform solvent were placed in a 1L glass beaker, and 10 compared to the maximum rotational speed using a homogenizer (homogenizer, product name: Homomixer mark2, manufacturer: primix, maximum rotational speed: 8,000 rpm) % was stirred for 30 minutes to prepare a biodegradable coating composition in which the PHA powder was completely dissolved.

(2) Manufacture of biodegradable articles

The biodegradable coating composition prepared in step (1) was applied on a substrate using a bar coater (manufacturer: RDS), and then dried at 25° C. for 5 minutes by hot air drying to a biodegradable article (coating layer). thickness: 10 μm) was prepared. At this time, the base material was uncoated and kraft paper (manufacturer: Hansol Paper) having a basis weight of ^{180 g/m 2 was used.}

<Wet coating process>

Example 3

(1) Preparation of a dispersion comprising a biodegradable coating composition

Content of polyhydroxyalkanoate (PHA) (4-hydroxybutyrate (4-HB): 10% by weight, weight average molecular weight (Mw): 800,000 g/mol, polydispersity index (PDI): 2.0, manufacturer: CJ) powder was prepared. The PHA powder was obtained by physical crushing using a homogenizer (product name: homomixer mark2, manufacturer: primix).

The PHA powder was centrifuged in an aqueous system to prepare a primary aqueous dispersion having a solid content of 40 wt%.

Then, 97 parts by weight of the first aqueous dispersion and 1 part by weight of polyvinyl alcohol (PVA, manufacturer: kuraray, hydration rate: 80%) of 10% concentration as a surfactant are placed in a 1L glass beaker, and a stirrer ( Product name: homo-disper, manufacturer: premix, maximum rotational speed per minute: 8,000 rpm) was stirred at 1,500 rpm for 60 minutes.

Thereafter, 1 part by weight of xanthan gum (manufacturer: Dain Material) having a concentration of 5% as a rheology control agent was additionally added, followed by stirring at 600 rpm for 10 minutes to prepare a dispersion.

(2) Manufacture of biodegradable articles

After applying the dispersion prepared in step (1) on the substrate using a mayer bar coater (manufacturer: RDS), it was dried at 150° C. for 5 minutes by hot air drying to a biodegradable article (thickness of the coating layer: 15 μm) was prepared. At this time, the base material was uncoated and kraft paper (manufacturer: Hansol Paper) having a basis weight of ^{180 g/m 2 was used.}

<Lamination process>

Example 4

(1) Preparation of biodegradable film

Content of polyhydroxyalkanoate (PHA) (4-hydroxybutyrate (4-HB): 10% by weight, weight average molecular weight (Mw): 800,000 g/mol, polydispersity index (PDI): 2.0, manufacturer: CJ) powder was prepared. The PHA powder was obtained by physical crushing using a homogenizer (product name: homomixer mark2, manufacturer: primix).

30 parts by weight of the PHA powder, 20 parts by weight of polyvinyl alcohol (PVA, manufacturer: kuraray, hydration rate: 80%) of 10% concentration as a surfactant, and 50 parts by weight of distilled water (DI water) in 1L of glass Put it in a beaker, and use a homogenizer (homogenizer, linear speed: 1,250 cm/sec, product name: Homomixer mark2, manufacturer: primix, maximum revolutions per minute: 12,000 rpm) for 30 minutes at 70% of the maximum revolutions per minute. A first aqueous dispersion was prepared by stirring.

Thereafter, the first aqueous dispersion is filtered using a pressure filter, washed with water, distilled water is further added, and redispersed in water using a homogenizer (product name: homomixer mark2, manufacturer: primix) 40 A biodegradable coating composition having a solids content of weight percent was prepared.

에서 용융 압출하고, 35℃에서 냉각하여 생분해성 필름(두께: 50 ㎛)을 제조하였다. Then, the biodegradable coating composition is 150 using an extruder.

was melt-extruded and cooled at 35° C. to prepare a biodegradable film (thickness: 50 μm).

(3) Manufacture of biodegradable articles

The biodegradable film prepared in step (1) was placed on the substrate to be laminated, and lamination was performed at 170° C. for 1 minute to prepare a biodegradable article. At this time, the base material was uncoated and kraft paper (manufacturer: Hansol Paper) having a basis weight of ^{180 g/m 2 was used.}

1: Biodegradable article
100: description
200: biodegradable coating layer
300: adhesive layer

Claims (25)

A method for producing a biodegradable article, comprising the step of forming a biodegradable coating layer on at least one surface of a substrate through a coating process selected from the group consisting of a melt extrusion process, a solvent casting process, a wet coating process, and a lamination process. The method of claim 1,
The method for producing a biodegradable article, wherein the biodegradable coating layer is formed from a biodegradable coating composition comprising a polyhydroxyalkanoate (PHA) resin. 3. The method of claim 2,
The method for producing a biodegradable article, wherein the polyhydroxyalkanoate (PHA) resin is a copolymerized polyhydroxyalkanoate resin comprising a 4-hydroxybutyrate (4-HB) repeating unit. 4. The method of claim 3,
The copolymer polyhydroxyalkanoate resin comprises a first PHA resin and a second PHA resin,
The first PHA resin comprises 0.1 to 30% by weight of a 4-hydroxybutyrate (4-HB) repeating unit,
The method for producing a biodegradable article, wherein the second PHA resin comprises 15 to 60% by weight of a 4-hydroxybutyrate (4-HB) repeating unit 3. The method of claim 2,
The biodegradable coating composition further comprises a biodegradable polymer,
The biodegradable polymer is polylactic acid (PLA), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), polybutylene succinate adipate ( PBSA), polybutylene adipate (PBA), polycaprolactone (PCL), thermoplastic starch (TPS), polypropylene (PP), at least one selected from the group consisting of polyethylene terephthalate (PET) and polyethylene (PE) A method for producing a biodegradable article comprising a. 3. The method of claim 2,
The method for producing a biodegradable article, wherein the biodegradable coating composition further comprises at least one additive selected from the group consisting of a surfactant, a rheology modifier, a crosslinking agent, an antioxidant, a stabilizer, and a pH adjuster. 7. The method of claim 6,
The surfactant is at least one selected from the group consisting of cationic surfactants, anionic surfactants, phosphoric acid surfactants, fatty acid surfactants, acrylic surfactants, urethane surfactants, epoxy surfactants and nonionic surfactants, or , carboxylic acid, amine, isocyanate, and a polymer surfactant comprising at least one selected from the group consisting of derivatives thereof, a method for producing a biodegradable article. The method of claim 1,
The substrate is paper, kraft paper, fabric, knitted fabric, nonwoven fabric, synthetic leather, glass, metal, plastic, polyethylene terephthalate (PET) film, polyimide (PI) film, polypropylene (PP) film or polyethylene (PE) film Phosphorus, a method for producing a biodegradable article. The method of claim 1,
The method for producing a biodegradable article, wherein the biodegradable article is a packaging material, a cardboard box, a shopping bag, disposable tableware, a packaging container or a paper straw. The method of claim 1,
Forming the biodegradable coating layer is performed through a melt extrusion process,
wherein the melt extrusion process comprises a melt extrusion step and a cooling step. 11. The method of claim 10,
The melt extrusion step is carried out at 120 °C to 180 °C, a method for producing a biodegradable article. 11. The method of claim 10,
The cooling step includes a primary cooling step and a secondary cooling step, and is performed through a cooling roll. The method of claim 1,
Forming the biodegradable coating layer is performed through a solvent casting process,
The solvent casting process comprises dissolving a polyhydroxyalkanoate (PHA) resin in a solvent to prepare a biodegradable coating solution; applying the biodegradable coating solution on a substrate; and drying, a method for producing a biodegradable article. 14. The method of claim 13,
The solvent is chloroform, ethyl acetate, butyl acetate, isobutyl acetate, amyl acetate, isoamyl acetate, isobutyl alcohol, 1-butanol, 1-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol , 3-pentanol, 1-hexanol, cyclohexanol, propyl propionate, butyl propionate, isobutyl propionate, ethyl butyrate, isobutyl isobutyrate, dichloromethane, N,N-dimethylformamide, At least one selected from the group consisting of dimethylacetamide, dimethylsulfoxide, N-methylpyrrolidone, methylethylketone, methylene chloride, tetrahydrofuran, toluene and acetone, a method for producing a biodegradable article. 14. The method of claim 13,
The viscosity of the biodegradable coating solution is 100 cps to 100,000 cps, the method for producing a biodegradable article. 14. The method of claim 13,
The application step is spin coating, dip coating, roll coating, screen coating, spray coating, spin casting, flow coating (flow coating). coating), screen printing, ink jet (ink jet), and a method for producing a biodegradable article is carried out by at least one method selected from the group consisting of drop casting (drop casting). 14. The method of claim 13,
The method for producing a biodegradable article, wherein the drying step is performed for 10 seconds to 10 minutes at 25 ℃ to 200 ℃ by hot air drying. The method of claim 1,
Forming the biodegradable coating layer is performed through a wet coating process,
The wet coating process comprises the steps of preparing a dispersion comprising a biodegradable coating composition; applying the dispersion on a substrate; and drying, a method for producing a biodegradable article. 19. The method of claim 18,
The viscosity of the dispersion is 100 cps to 1000 cps, the method for producing a biodegradable article. 19. The method of claim 18,
At least one method wherein the coating step is selected from the group consisting of gravure coating, microgravure coating, capillary coating, slit coating, and bar coating A method for producing a biodegradable article, which is carried out as 19. The method of claim 18,
The method for producing a biodegradable article, wherein the drying step is performed for 10 seconds to 10 minutes at 100 ° C. to 200 ° C. by hot air drying. 19. The method of claim 18,
The method for producing a biodegradable article, wherein the drying step is performed for 10 seconds to 10 minutes using infrared rays having a wavelength of 700 nm to 2,500 nm or ultraviolet rays having a wavelength of 200 nm to 400 nm. The method of claim 1,
Forming the biodegradable coating layer is performed through a lamination process,
The lamination process comprising the step of laminating a biodegradable film on a substrate, a method of manufacturing a biodegradable article. 24. The method of claim 23,
The lamination is performed through an adhesive layer,
The adhesive layer comprises at least one selected from the group consisting of polyhydroxyalkanoate (PHA) resin, polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), acrylic resin, and urethane-based resin, Manufacturing of a biodegradable article Way. 24. The method of claim 23,
A biodegradable coating composition in which the biodegradable film includes a polyhydroxyalkanoate (PHA) resin is subjected to a melt extrusion process (extrusioion molding), a T-die process (T-die), a calendar process (calendaring) and a stretching process. A method for producing a biodegradable article, which is manufactured through one or more methods selected from the group consisting of.

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