WO2023008902A1

WO2023008902A1 - Biodegradable resin composition, and biodegradable film and biodegradable product using same

Info

Publication number: WO2023008902A1
Application number: PCT/KR2022/011026
Authority: WO
Inventors: 여준석; 정민호; 김정수; 박정일; 윤기철
Original assignee: 씨제이제일제당(주)
Priority date: 2021-07-30
Filing date: 2022-07-27
Publication date: 2023-02-02
Also published as: KR20210111186A

Abstract

The present invention relates to a biodegradable resin composition including a polyhydroxyalkanoate (PHA) resin and a polybutyleneadipate terephthalate (PBAT) resin. The biodegradable resin composition, which includes, based on the total weight of the biodegradable resin composition, 40 wt% to 99 wt% of the PHA resin and 1 wt% to 60 wt% of the PBAT resin, and a biodegradable film and a biodegradable product that use same are provided. By having the specific compositions, the biodegradable resin composition according to an embodiment may be able to improve the mechanical characteristics and optical characteristics of a biodegradable film formed therefrom simultaneously, may enable biodegradation both in the soil and the ocean, and thus may exhibit excellent characteristics when applied to more diverse fields.

Description

Biodegradable resin composition, and biodegradable film and biodegradable product using the same

The present invention relates to a biodegradable resin composition, and a biodegradable film and biodegradable product using the same.

Demand for currently commercialized general-purpose plastics is on the rise due to their excellent physical properties, stable supply and price. However, due to this, the waste plastic treatment problem is emerging throughout life, and it is not decomposed in a natural state such as the ocean and soil, which causes serious environmental pollution problems.

On the other hand, methods such as landfill, incineration, and recycling have been mainly used for the treatment of waste plastics that do not decompose. Among them, recycling has been considered as the most effective way to solve environmental problems and resource depletion. This is not done, and there is a limit to solving the environmental pollution problem.

In order to solve this problem, polylactic acid (PLA), polybutylene adipate terephthalate (polybutylene adipate terephthalate , PBAT), polybutylene succinate (PBS), etc., studies using various biodegradable resins have been actively conducted. However, it is difficult to actually biodegrade, or it takes a long time to decompose, and in particular, there is a limit to complete biodegradation in the natural state of the ocean and soil.

In addition, when the biodegradable resin is applied to a bag, excellent biodegradability as well as excellent mechanical properties are required.

For example, a pay-as-you-go bag requires excellent mechanical properties such as strength and flexibility to handle the weight of various wastes, and also requires excellent optical transparency to check the contents.

To this end, PLA was applied to the envelope, but the PLA is biodegradable, but has a problem of insufficient resistance to tearing (tear) due to low flexibility.

Accordingly, although the PLA and PBAT were mixed and applied, there is a limit to implementing excellent biodegradability in both marine and soil, and there is a problem in that it is difficult to check the contents of the bag due to low optical properties.

[Prior art literature]

[Patent Literature]

(Patent Document 1) Korean Patent Publication No. 2006-0039967

An object of the present invention is to provide a biodegradable resin composition that is biodegradable in both soil and sea while having excellent mechanical properties such as tensile strength, elongation, flexibility and impact resistance and optical properties of light transmittance.

Another object of the present invention is to provide a biodegradable film formed from the biodegradable resin composition and a manufacturing method thereof.

Another object of the present invention is to provide a biodegradable product formed from the biodegradable resin composition and biodegradable in both soil and ocean.

The present invention is a biodegradable resin composition comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin, based on the total weight of the biodegradable resin composition, the polyhydroxyal It provides a biodegradable resin composition comprising 40% to 99% by weight of a carnoate (PHA) resin and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin.

In addition, the present invention is a biodegradable film comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin, based on the total weight of the biodegradable film, the polyhydroxyal A biodegradable film comprising 40% to 99% by weight of a carnoate (PHA) resin and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin is provided.

In addition, the present invention 1) preparing a biodegradable pellet (pellet) containing a polyhydroxyalkanoate (PHA) resin and polybutylene adipate terephthalate (PBAT) resin; And 2) a method for producing a biodegradable film comprising the step of molding the biodegradable pellets, based on the total weight of the biodegradable film, the polyhydroxyalkanoate (PHA) resin in an amount of 40% to 99% by weight It provides a method for producing a biodegradable film comprising 1 wt% to 60 wt% of the polybutylene adipate terephthalate (PBAT) resin.

Furthermore, the present invention provides a biodegradable product formed from the biodegradable resin composition.

The biodegradable resin composition according to an embodiment includes a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin in specific amounts, thereby improving mechanical properties of tensile strength, elongation, flexibility and impact resistance. And it is possible to provide a biodegradable film that has excellent optical properties of light transmittance and is biodegradable in both soil and ocean.

Therefore, the biodegradable film formed from the biodegradable resin composition according to another embodiment is a variety of biodegradable products such as biodegradable bags, biodegradable volume-rate bags, biodegradable shopping bags, biodegradable plastic bags, biodegradable zipper bags, and biodegradable garbage bags. It can be applied to, and can effectively act on environmental preservation with excellent physical properties.

1 shows a flow chart of a manufacturing process of a biodegradable film according to an embodiment of the present invention.

Hereinafter, the present invention will be described in more detail.

Embodiments are not limited to the contents disclosed below, and may be modified in various forms unless the gist of the invention is changed.

In this specification, when a certain component is said to "include", this means that it may further include other components, not excluding other components, unless otherwise stated.

In addition, it should be understood that all numerical ranges representing physical property values, dimensions, etc. of components described in this specification are modified by the term "about" in all cases unless otherwise specified.

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

[생분해성 수지 조성물][Biodegradable Resin Composition]

The biodegradable resin composition according to an embodiment of the present invention is a biodegradable resin composition comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin, the biodegradable resin composition Based on the total weight, including 40% to 99% by weight of the polyhydroxyalkanoate (PHA) resin and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin .

By having the specific composition, the biodegradable resin composition can simultaneously improve mechanical properties such as tensile strength, elongation, flexibility and impact resistance, and optical properties such as light transmittance. In addition, the biodegradable film formed therefrom can be biodegraded in both soil and ocean, and can be applied to more diverse fields to exhibit excellent properties.

Hereinafter, each component of the biodegradable resin composition will be described in detail.

폴리하이드록시알카노에이트(PHA) 수지Polyhydroxyalkanoate (PHA) resin

The biodegradable resin composition according to an embodiment of the present invention includes a polyhydroxyalkanoate (hereinafter referred to as PHA) resin.

The PHA resin is polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA) derived from conventional petroleum. ), while having properties similar to those of synthetic polymers, it exhibits complete biodegradability and excellent biocompatibility.

Specifically, the PHA resin is a thermoplastic natural polyester polymer that accumulates in microbial cells, and can be composted as a biodegradable material and can be finally decomposed into carbon dioxide, water, and organic waste without generating toxic waste. In particular, since the PHA resin can be biodegraded in soil and ocean, when the biodegradable resin composition includes the PHA resin, it is biodegradable in any environmental conditions such as soil and ocean and has environmentally friendly characteristics. Therefore, the biodegradable film formed using the biodegradable resin composition containing the PHA resin can be used in various fields as an eco-friendly product.

The PHA resin may be formed by enzyme-catalyzed polymerization of one or more monomer repeating units in living cells.

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

Examples of repeating units that can be incorporated into the PHA include 2-hydroxybutyrate, lactic acid, glycolic acid, 3-hydroxybutyrate (hereinafter referred to as 3-HB), 3-hydroxypropionate (hereinafter, 3-HP), 3-hydroxyvalerate (hereinafter referred to as 3-HV), 3-hydroxyhexanoate (hereinafter referred to as 3-HH), 3-hydroxyheptanoate (hereinafter referred to as 3-HHep), 3-hydroxyoctanoate (hereinafter referred to as 3-HO), 3-hydroxynonanoate (hereinafter referred to as 3-HN), 3-hydroxy 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) There may be, and the PHA resin may contain one or more repeating units selected from these.

Specifically, the PHA resin includes one or more repeating units selected from the group consisting of 3-HB, 4-HB, 3-HP, 3-HH, 3-HV, 4-HV, 5-HV and 6-HH. can do.

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

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, while the PHA resin includes a 4-HB repeating unit, it further includes one repeating unit different from the 4-HB, or two, three, four, five, six or more different from each other. It may be a PHA copolymer further comprising a repeating unit.

According to one embodiment of the present invention, the PHA resin contains one or more repeating units selected from the group consisting of 3-HB, 3-HP, 3-HH, 3-HV, 4-HV, 5-HV and 6-HH. , and a copolymerized polyhydroxyalkanoate resin containing 4-HB repeating units.

Specifically, the PHA copolymer 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, 5-HV 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 PHA resin may be a copolymerized polyhydroxyalkanoate resin containing 3-HB repeating units and 4-HB repeating units.

For example, the PHA resin may be poly 3-hydroxybutyrate-co-4-hydroxybutyrate (hereinafter referred to as 3HB-co-4HB).

According to one embodiment of the present invention, it is important to control the content of the 4-HB repeating unit in the PHA copolymer.

That is, in order to implement the physical properties desired in the present invention, in particular, to improve the biodegradability of soil and ocean, and to implement excellent physical properties such as improved optical properties, thermal properties, and mechanical properties, the 4- The content of HB repeat units may be important.

More specifically, the PHA copolymer may include 0.1% to 60% by weight of 4-HB repeating units based on the total weight of the PHA copolymer. For example, the content of the 4-HB repeating unit is, for example, 0.1 to 55% by weight, 0.5 to 60% by weight, 0.5 to 55% by weight, 1% to 60% by weight based on the total weight of the PHA copolymer. %, 1% to 55%, 1% to 50%, 2% to 55%, 3% to 55%, 3% to 50%, 5% to 55%, 5% to 50% by weight, 10% to 55% by weight, 10% to 50% by weight, 1% to 40% by weight, 1% to 30% by weight, 1% to 29% by weight, 1% by weight % to 25 wt%, 1 wt% to 24 wt%, 2 wt% to 20 wt%, 2 wt% to 23 wt%, 3 wt% to 20 wt%, 3 wt% to 15 wt%, 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% to 50%, 25% to 55%, 25% to 50%, 35% to 60%, 40% to 55% or 45% to 55% can

When the content of the 4-HB repeating unit satisfies the above range, biodegradability of soil and sea is improved, excellent optical properties are maintained, thermal properties of the material are improved, and mechanical properties such as flexibility and strength are further improved. can improve

In addition, the PHA resin may include at least one 4-HB repeating unit, and the crystallinity of the PHA resin may be adjusted by controlling the content of the 4-HB repeating unit. That is, the PHA resin may be a PHA copolymer having controlled crystallinity.

The PHA resin (PHA copolymer) having controlled crystallinity may have crystallinity and amorphousness controlled by increasing irregularity in molecular structure, specifically, the type of monomer, the ratio of monomers or the type of isomer and/or The content may have been adjusted.

The PHA resin may include a combination of two or more PHA resins having different crystallinity. That is, the PHA resin may be adjusted to have a content of 4-HB repeating units within the specific range by mixing two or more types of PHA resins having different crystallinity.

For example, the PHA resin includes a mixed resin of a first PHA resin and a second PHA resin having different contents of 4-HB repeating units, and the PHA resin has 4-HB repeating units based on the total weight of the PHA resin. It may be adjusted to be 0.1 to 60% by weight. Specific characteristics of the first PHA resin and the second PHA resin may be referred to below.

Meanwhile, the PHA copolymer contains, for example, 20% by weight or more, 35% by weight or more, 40% by weight or more, 50% by weight or more, 60% by weight or more of 3-HB repeating units based on the total weight of the PHA copolymer. , 70% by weight or more, or may include 75% by weight or more, 99% by weight or less, 98% by weight or less, 97% by weight or less, 96% by weight or less, 95% by weight or less, 93% by weight or less, 91% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, 60% by weight or less, or 55% by weight or less.

On the other hand, the PHA resin has a glass transition temperature (Tg) of, for example, -45 ° C to 80 ° C, -35 ° C to 80 ° C, -30 ° C to 80 ° C, -25 ° C to 75 ° C, -20 ° C to 70 ° C ℃, -35 ℃ to 5 ℃, -25 ℃ to 5 ℃, -35 ℃ to 0 ℃, -25 ℃ to 0 ℃, -45 ℃ to -10 ℃, -30 ℃ to -10 ℃, -35 ℃ 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 PHA resin may have a crystallization temperature (Tc) of, for example, unmeasured, or may be, for example, 70°C to 120°C, 75°C to 120°C, 75°C to 115°C, 75°C to 110°C, or 90°C. to 110 °C.

The PHA resin may have a melting temperature (Tm), for example, which may not be measured, or may be, for example, 100 ° C to 170 ° C, eg 110 ° C to 150 ° C, or eg 120 ° C to 140 ° C. .

The PHA resin may have a weight average molecular weight (Mw) of, for example, 10,000 g/mol to 1,200,000 g/mol. For example, the weight average molecular weight of the PHA 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 , 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 , 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 , 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, or 600,000 g/mol to 900,000 g/mol.

The PHA resin may include a first PHA resin, a second PHA resin, or a mixed resin of the first PHA resin and the second PHA resin.

The first PHA resin and the second PHA resin may have different 4-HB repeating unit content, glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm).

Specifically, the first PHA resin contains the 4-HB repeating unit in an amount of, for example, 15% to 60% by weight, 15% to 55% by weight, or 20% by weight based on the total weight of the first PHA resin. to 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 % by weight, 35% to 50% by weight, or 20% to 40% by weight.

The first PHA resin has a glass transition temperature (Tg) of, for example, -45 ° C to -10 ° C, -35 ° C to -10 ° C, -35 ° C to -15 ° C, -35 ° C to -20 ° C, or -30°C to -20°C.

The first PHA resin may have a crystallization temperature (Tc), for example, may not be measured, or may be, for example, 60 ° C to 120 ° C, 60 ° C to 110 ° C, 70 ° C to 120 ° C, or 75 ° C to 115 ° C. can

The first PHA resin may have, for example, a melting temperature (Tm) that may not be measured, or may be, for example, 100°C to 170°C, 100°C to 160°C, 110°C to 160°C, or 120°C to 150°C. can

The first PHA resin has a weight average molecular weight (Mw) of, for example, 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, 50,000 g/mol to 1,200,000 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.

Meanwhile, the second PHA resin may include the 4-HB repeating unit in an amount of 0.1% to 30% by weight based on the total weight of the second PHA resin. For example, the second PHA resin includes 0.1% to 30% by weight, 0.5% to 30% by weight, 1% to 30% by weight, 3% to 30% by weight of the 4-HB repeating unit, for example. , 1% to 28% by weight, 1% to 25% by weight, 1% to 24% by weight, 1% to 20% by weight, 1% to 15% by weight, 2% to 25% by weight, 3 % to 25%, 3% to 24%, 5% to 24%, 5% to 20%, greater than 5% to less than 20%, 7% to 20%, 10 It may be included at 20% by weight, 15% by weight to 25% by weight, or 15% by weight to 24% by weight.

The first PHA resin and the second PHA resin may have different 4-HB repeating unit contents.

The second PHA resin has a glass transition temperature (Tg) of, for example, -30 ° C to 80 ° C, for example -30 ° C to 10 ° C, for example -25 ° C to 5 ° C, for example -25 ° C to 0°C, for example -20°C to 0°C, or for example -15°C to 0°C.

The glass transition temperature (Tg) of the first PHA resin and the glass transition temperature (Tg) of the second PHA resin may be different from each other.

The second PHA resin may have a crystallization temperature (Tc) of, for example, 70 ° C to 120 ° C, 75 ° C to 115 ° C, or 80 ° C to 110 ° C, or, for example, not measured.

The second PHA resin has a melting temperature (Tm) of, for example, 100 ° C to 170 ° C, for example 105 ° C to 165 ° C, for example 110 ° C to 160 ° C, for example 100 ° C to 150 ° C, for example For example, it may be 115 ° C to 155 ° C, eg 120 ° C to 160 ° C, or eg 120 ° C to 150 ° C.

The second PHA resin has a weight average molecular weight (Mw) of 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, 300,000 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, 200,000 g/mol to 400,000 g/mol, or 400,000 g/mol to 700,000 g/mol.

Specifically, the first PHA resin has a glass transition temperature (Tg) of -35 ° C to -15 ° C, and the second PHA resin has a glass transition temperature (Tg) of -15 ° C to 0 ° C, 80 ° C to 110 ° C It satisfies at least one characteristic selected from a crystallization temperature (Tc) of ° C and a melting temperature (Tm) of 120 ° C to 160 ° C, and the glass transition temperature (Tg) of the first PHA resin and the glass transition temperature (Tg) of the second PHA resin Transition temperatures (Tg) may be different from each other. In addition, the crystallization temperature (Tc) and melting temperature (Tm) of the first PHA resin may not be measured.

When the first PHA resin and the second PHA resin each satisfy at least one or more of the 4-HB repeating unit, glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm) in the above range, It may be more advantageous to achieve the desired effect in the present invention.

In addition, the first PHA resin and the second PHA resin may each be a PHA resin having an adjusted crystallinity (crystallinity).

For example, the first PHA resin may include an amorphous PHA resin (hereinafter referred to as aPHA resin), and the second PHA resin may include a semi-crystalline PHA resin (hereinafter referred to as scPHA resin). can

The "aPHA" resin and the "scPHA" resin may be distinguished according to the content of "4-HB" repeating unit, "glass transition temperature (Tg)," "crystallization temperature (Tc)," and "melting temperature (Tm)".

The "aPHA" resin may include "4-HB" repeating units, for example, 25 to "50% by weight" based on the total weight of the "PHA" resin.

The aPHA resin may have a glass transition temperature (Tg) of, for example, -35°C to -20°C.

The crystallization temperature (Tc) of the "aPHA" resin may not be measured.

The melting temperature (Tm) of the "aPHA" resin may not be measured.

The "scPHA" resin may include "4-HB" repeating units in an amount of, for example, less than 1 to "25% by weight" based on the total weight of the "PHA" resin.

The "scPHA" resin may have a glass transition temperature (Tg) of -20°C to "0°C.

The crystallization temperature (Tc) of the “scPHA” resin may be 75° C. to 115° C.

The melting temperature (Tm) of the scPHA resin may be, for example, 110°C to 160°C.

On the other hand, in order to achieve the effect according to an embodiment of the present invention, the content of the PHA resin included in the biodegradable resin composition is important.

The biodegradable resin composition contains the PHA resin in an amount of 40% by weight or more, 50% by weight or more, 55% by weight or more, 60% by weight or more, 65% by weight or more, or 70% by weight based on the total weight of the biodegradable resin composition. It may contain more than 99% by weight, 95% by weight or less, 90% by weight or less, 85% by weight or less, or 80% by weight or less.

The biodegradable resin composition may include, for example, 40 to 99% by weight, 50 to 95% by weight, or 40% to 80% by weight of the PHA resin based on the total weight of the biodegradable resin composition.

The PHA resin included in the biodegradable resin composition may be selected within the above range depending on the intended use. In this case, the biodegradation effect is very excellent in both soil and marine, and in particular, the marine biodegradability is excellent, and the optical properties are excellent. this can be improved.

Meanwhile, when the PHA resin includes the first PHA resin, for example, 1% to 95% by weight may be used, and when the first PHA resin is used alone, based on the total weight of the biodegradable resin composition. As such, the first PHA resin may be included in an amount of, for example, 5 to 80% by weight. Specifically, the first PHA resin may be included in an amount of 10% by weight or more and 70% by weight or less.

As another example, when the first PHA resin is mixed with the second PHA resin and used, the first PHA resin is used in an amount of, for example, 1 to 50% by weight, based on the total weight of the biodegradable resin composition. For example, it may include 10 to 40% by weight, or, for example, 20 to 40% by weight.

When the PHA resin includes the second PHA resin, based on the total weight of the biodegradable resin composition, for example, 1% to 95% by weight of the second PHA resin may be used, and the second PHA resin When used alone, based on the total weight of the biodegradable resin composition, the second PHA resin may comprise 50% by weight or more, 55% by weight or more, 60% by weight or more, 65% by weight or more, or 70% by weight or more. 95% by weight or less, 90% by weight or less, 85% by weight or less, or 80% by weight or less. When the second PHA resin is used alone, for example, 50 to 95% by weight of the second PHA resin may be included based on the total weight of the biodegradable resin composition.

As another example, when the second PHA resin is mixed with the first PHA resin and used, the second PHA resin is used in an amount of, for example, 20 to 80% by weight, based on the total weight of the biodegradable resin composition. For example, it may be included in 30 to 70% by weight, or, for example, 30 to 50% by weight.

For example, the biodegradable resin composition may include 1% to 50% by weight of the first PHA resin, 20% to 80% by weight of the second PHA resin, and the poly, based on the total weight of the biodegradable resin composition. It may include 1 wt % to 50 wt % of butylene adipate terephthalate (PBAT) resin.

According to another embodiment of the present invention, when the PHA resin includes a mixed resin of the first PHA resin and the second PHA resin, the weight ratio of the first PHA resin to the second PHA resin is, for example, 1:0.05. to 5, for example 1:0.5 to 4, or for example 1:1.2 to 4.

When the contents of the PHA resin, or the first PHA resin and the second PHA resin, and their content ratios are within the above range, the optical properties, thermal properties, and mechanical properties can be further improved and biodegradable. Formability, processability, and productivity can also be improved when producing a film or molded product.

폴리부틸렌아디페이트 테레프탈레이트(PBAT) 수지Polybutylene adipate terephthalate (PBAT) resin

The biodegradable resin composition according to an embodiment of the present invention includes a polybutylene adipate terephthalate (hereinafter referred to as PBAT) resin.

The PBAT resin is a biodegradable polyester resin that is decomposed into carbon dioxide and water by microorganisms in the soil by hydrolysis.

According to an embodiment of the present invention, by including the PBAT resin in the biodegradable resin composition, it can be naturally degraded by microorganisms, etc., which is environmentally friendly, and has properties such as breaking strength, tensile strength, elongation (elongation), optical properties, hardness, melting Mechanical properties such as melt strength and water resistance can be improved, and in particular, flexibility can be improved while maintaining appropriate strength by improving tensile strength and elongation (elongation). In particular, the PBAT resin has advantages of higher strength and elasticity and higher elongation than other biodegradable polyester resins, such as PLA resin or PBS resin. For this reason, by using the PBAT resin together with the PHA resin, it can be used in various biodegradable products, in particular, biodegradable bags, biodegradable volume-based bags, and biodegradable shopping bags that require strength, elasticity, and elongation (flexibility) characteristics. , biodegradable plastic bags, biodegradable zipper bags, and biodegradable garbage bags.

If the PHA resin is used alone, since the PHA resin may be soft due to its low crystallinity, mechanical properties such as tensile strength and hardness may be lowered due to the limitations of these physical properties, and as a result, the product may be deteriorated. It is unsuitable for molding or has very low productivity, so its use may be very limited.

In the biodegradable resin composition of one embodiment of the present invention, the PBAT resin is an aliphatic-aromatic polyester copolymer, which can be obtained by condensation polymerization of 1,4-butanediol, adipic acid, and terephthalic acid according to a generally known method.

In addition, the PBAT resin may have a weight average molecular weight (Mw) of about 100,000 to 500,000 g/mol or about 150,000 to 400,000 g/mol. As the PBAT resin has such a molecular weight range, compatibility and processability with the PHA resin may be further improved, and the resin composition of one embodiment may exhibit improved mechanical properties and the like according to a relatively high molecular weight. In addition, by this molecular weight range, the transparency of the resin composition and the film formed therefrom may also be maintained excellently.

The biodegradable resin composition according to an embodiment of the present invention may include 1% to 60% by weight of the PBAT resin based on the total weight of the biodegradable resin composition.

Specifically, the content of the PBAT resin is, for example, 1% to 50% by weight, for example 5% to 40% by weight, for example 10% to 40% by weight, or for example 10% to 40% by weight. 30% by weight.

When the content of the PBAT resin satisfies the above range, the fracture strength, for example, low and room temperature impact strength is excellent, and physical properties such as tensile strength, elongation, hardness, flow properties, solidification rate, optical properties, barrier properties, and melt tension can be improved, and in particular, the tensile strength and elongation are excellent, so that appropriate strength and flexibility can be satisfied at the same time.

On the other hand, the biodegradable composition according to an embodiment of the present invention may include the PHA resin and the PBAT resin in a weight basis (weight ratio) of 1: 0.01 to 1, 1: 0.10 to 0.6, or 1: 0.01 to 0.4. can

When the weight ratio of the PHA resin and the PBAT resin satisfies the above content ratio, optical properties, molding properties, and mechanical properties can be further improved, and biodegradability, processability, and productivity can be improved when manufacturing a biodegradable film. there is.

생분해성 수지biodegradable resin

The biodegradable resin composition according to an embodiment of the present invention is a component that provides biodegradability while securing mechanical properties suitable for the use of a biodegradable film or product manufactured using the same, and includes an aliphatic polyester-based biodegradable resin, and It may further include at least one selected from the group consisting of aliphatic/aromatic copolyester-based biodegradable resins.

Specifically, the type of the biodegradable resin is not particularly limited as long as it is commonly used, and representative biodegradable resins include polybutylene succinate (PBS), polylactic acid (PLA), polybutylene adipate (PBA), polybutylene adipate (PBA), Butylenesuccinate-adipate (PBSA), polybutylenesuccinate-terephthalate (PBST), polyhydroxybutylate-valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate tere It may include at least one selected from the group consisting of phthalate (PBSAT) and thermoplastic starch (TPS). Specifically, the biodegradable resin may include at least one selected from the group consisting of polybutylene succinate (PBS), polylactic acid (PLA), and thermoplastic starch (TPS). More specifically, the biodegradable resin may include at least one selected from the group consisting of polybutylene succinate (PBS) and polylactic acid (PLA).

The biodegradable resin is based on the total weight of the biodegradable resin composition, 45% by weight or less, specifically for example 0.01% to 40% by weight, for example 1% to 40% by weight, or for example 5 to 30% by weight.

When the biodegradable resin composition includes the biodegradable resin in the above range, it is possible to achieve mechanical properties suitable for various uses of the biodegradable film, so there is an advantage that it can be used in various ways. That is, by further including the biodegradable resin in the biodegradable resin composition, tensile strength and elongation can be further improved.

첨가제additive

The biodegradable resin composition may further include one or more additives selected from the group consisting of antioxidants, compatibilizers, weighting agents, nucleating agents, melt strength enhancing agents, and slip agents.

The additive may be included in an amount of 0.1% to 30% by weight based on the total weight of the biodegradable resin composition.

The additive may be at least 0.1%, at least 0.5%, at least 1%, at least 1.5%, or at least 2% by weight. The additive may be 30 wt% or less, 28 wt% or less, 25 wt% or less, 20 wt% or less, 15 wt% or less, 10 wt% or less, 8 wt% or less, or 5 wt% or less.

The antioxidant is an additive for preventing decomposition by ozone or oxygen, preventing oxidation during storage, and preventing deterioration of physical properties of a biodegradable film formed from the biodegradable resin composition.

As the antioxidant, any commonly used antioxidant may be used as long as the effect of the present invention is not impaired.

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

The hindered phenolic antioxidant is, for example, 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), 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 One or more selected species may be included.

The phosphite-based (phosphorus) antioxidant is, for example, tris-(2,4-di-t-butylphenyl) phosphite, bis-(2,4-di-t-butylphenyl)pentaerythritol-dipo Spite, 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]deoxyphosphepin-6-yl]oxy]-ethyl]ethanamine.

The antioxidant may be included in, for example, 0.01 to 10% by weight, for example, 0.01 to 5% by weight, for example, 0.01 to 3% by weight based on the total weight of the biodegradable resin composition.

When the antioxidant satisfies the above content range, physical properties of a biodegradable film formed from the biodegradable composition may be improved, and it may be more advantageous to achieve desired effects in the present invention.

The compatibilizer is an additive for imparting compatibility by removing releasability of the PHA resin, the PBAT resin, and/or the biodegradable resin.

As the compatibilizer, a commonly used compatibilizer may be used as long as the effect of the present invention is not impaired.

Specifically, the compatibilizer is composed of polyvinyl acetate (PVAc), isocyanate, polypropylene carbonate, glycidyl methacrylate, ethylene vinyl alcohol, polyvinyl alcohol (PVA), ethylene vinyl acetate, and maleic anhydride. It may contain one or more selected from the group.

The compatibilizer is, for example, 0.01 to 20% by weight, for example 0.01 to 15% by weight, for example 0.01 to 12% by weight, for example 0.01 to 10% by weight based on the total weight of the biodegradable resin composition, For example, 0.01 to 8% by weight, eg 0.01 to 5% by weight, eg 0.1 to 4.5% by weight, eg 0.1 to 3% by weight, or eg 0.1 to 2% by weight.

When the compatibilizer satisfies the content range, the compatibility between the resins used can be increased to improve the physical properties of the biodegradable film formed from the biodegradable composition, and it will be more advantageous to achieve desired effects in the present invention. can

The weighting agent is an inorganic material, and is an additive added to increase moldability by increasing the crystallization rate in the molding process and to reduce the problem of cost increase due to the use of a biodegradable resin.

As long as the weighting agent does not impair the effects of the present invention, commonly used inorganic materials may be used.

Specifically, the weighting agent is at least one selected from the group consisting of calcium carbonate, such as light or heavy calcium carbonate, silica, talc, kaolin, barium sulfate, clay, calcium oxide, magnesium hydroxide, titanium oxide, carbon black, and glass fibers can include

The weighting agent may have an average particle size of 0.5 μm to 10 μm. If the average particle size of the weighting agent is less than 0.5 μm, it becomes difficult to disperse the particles, and if it exceeds 10 μm, the size of the particles becomes excessively large, which may hinder the effect of the present invention.

The weighting agent may be included in, for example, 0.01 to 30% by weight, for example, 3 to 25% by weight, for example, 3 to 20% by weight based on the total weight of the biodegradable resin composition.

When the weighting agent satisfies the above content range, it may be more advantageous to achieve the desired effect in the present invention.

The nucleating agent is an additive for assisting or changing the crystallization form of the polymer and improving the solidification rate when the polymer melt is cooled. In particular, since the PHA resin used in the present invention has a low solidification rate, process suitability as a soft material may not be easy. When the nucleating agent is used, the solidification rate can be improved to further improve processability, moldability and productivity, and the desired physical properties can be efficiently achieved in the present invention.

As the nucleating agent, any commonly used nucleating agent may be used as long as the effect of the present invention is not impaired.

Specifically, the nucleating agent is a single element material (pure material), a metal compound including a complex oxide, for example, carbon black, calcium carbonate, synthetic silicic acid and salts, silica, zinc white, clay, kaolin, basic magnesium carbonate, mica, talc, quartz powder, diatomite, dolomite powder, titanium oxide, zinc oxide, antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, metal salts of organic phosphorus and boron nitride; Low molecular weight organic compounds having metal carboxylate groups, such as octylic acid, toluic acid, heptanoic acid, pelargonic acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, cerotic acid, montanic acid, melissic acid, benzene acid, p-tert-butylbenzene acid, terephthalic acid, terephthalic acid monomethyl ester, isophthalic acid and iso metal salts of each phthalic acid monomethyl ester; A polymer organic compound having a metal carboxylate group, for example, a carboxyl group-containing polyethylene obtained by oxidation of polyethylene, a carboxyl group-containing polypropylene obtained by oxidation of polypropylene, acrylic acid or methacrylic acid and an olefin ( For example, metal salts of copolymers of ethylene, propylene and butene-1), copolymers of acrylic acid or methacrylic acid and styrene, copolymers of olefin and maleic anhydride, and copolymers of styrene and maleic anhydride; A polymeric organic compound, for example, an alpha-olefin having 5 or more carbon atoms branched to a carbon atom in position 3 (e.g., 3,3 dimethylbutene-1,3-methylbutene-1,3-methylpentene-1 ,3-methylhexene-1 and 3,5,5-trimethylhexene-1), polymers of vinylcycloalkanes (eg vinylcyclopentane, vinylcyclohexane and vinylnorbornane), polyalkylene glycols (eg polyethylene glycol and polypropylene glycol), poly(glycolic acid), cellulose, cellulose esters and cellulose ethers; Phosphoric acid or phosphorous acid and metal salts thereof, such as diphenyl phosphate, diphenyl phosphite, metal salts of bis(4-tert-butylphenyl)phosphate and methylene bis-(2,4-tert-butylphenyl) phosphate; sorbitol derivatives such as bis(p-methylbenzylidene) sorbitol and bis(p-ethylbenzylidene) sorbitol; and thioglycolic anhydride, p-toluenesulfonic acid and metal salts thereof. These nucleating agents may be used alone or in combination with each other.

The nucleating agent may be included in, for example, 0.01 to 10% by weight, for example, 0.01 to 8% by weight, or, for example, 0.1 to 3% by weight, based on the total weight of the biodegradable resin composition.

When the nucleating agent satisfies the above content range, solidification is improved to improve formability, for example, when cutting for pellet production or in the manufacturing process, productivity is improved by improving solidification and Machinability can be further improved.

The melt strength enhancer is an additive for improving the reactive melt strength.

As the melt strength enhancer, any commonly used melt strength enhancer may be used as long as the effects of the present invention are not impaired.

Specifically, the melt strength enhancer is polyester, styrene-based polymers (eg, acrylonitrile butadiene styrene and polystyrene), polysiloxane, organo-modified siloxane polymer, polyester, and maleic anhydride grafted ethylene propylene diene monomer (MAH-g -EPDM) may include one or more selected from the group consisting of.

The melt strength enhancer is, for example, 0.01 to 10% by weight, for example 0.01 to 8% by weight, for example 0.1 to 5% by weight, or for example 0.1 to 3% by weight based on the total weight of the biodegradable resin composition. % can be included.

When the melt strength enhancer satisfies the above content range, it may be more advantageous to achieve the desired effect in the present invention.

The slip agent is an additive for improving slip properties (slipperiness) during extrusion and preventing film surfaces from sticking together during a process.

As long as the slip agent does not impair the effects of the present invention, commonly used slip agents may be used. For example, at least one selected from erucamide, oliamide, and stearamide may be used as the slip agent.

The slip agent is, for example, 0.01 to 20% by weight, for example 0.01 to 15% by weight, for example 0.01 to 12% by weight, for example 0.01 to 10% by weight based on the total weight of the biodegradable resin composition, For example, 0.01 to 8% by weight, eg 0.01 to 5% by weight, eg 0.2 to 4.5% by weight, eg 0.2 to 3% by weight, or eg 0.2 to 1% by weight.

When the slip agent satisfies the above content range, processability, productivity, and moldability may be further improved, and it may be more advantageous to achieve desired effects in the present invention.

As other additives, the biodegradable resin composition may also include a crosslinking agent and/or a stabilizer.

The crosslinking agent is an additive for modifying the properties of PHA and increasing the molecular weight of the resin, and any commonly used crosslinking agent may be used as long as the effect of the present invention is not impaired.

For example, the crosslinking agent is a fatty acid ester, or natural oil containing an epoxy group (epoxylated), diallylphthalate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaeryth At least one selected from the group consisting of litol pentaacrylate, diethylene glycol dimethacrylate, and bis(2-methacryloxyethyl)phosphate may be used.

For example, 0.01 to 20% by weight, for example 0.01 to 15% by weight, for example 0.01 to 12% by weight, for example 0.01 to 10% by weight, for example, based on the total weight of the biodegradable resin composition. For example, 0.01 to 8% by weight, eg 0.01 to 5% by weight, eg 0.01 to 3% by weight, eg 0.01 to 2% by weight, or eg 0.05 to 1% by weight.

The stabilizer is an additive for protecting against oxidation and heat and preventing color change. As the stabilizer, a commonly used stabilizer may be used as long as the effect of the present invention is not impaired.

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

The stabilizer is, for example, 0.01 to 20% by weight, for example 0.01 to 15% by weight, for example 0.01 to 12% by weight, for example 0.01 to 10% by weight based on the total weight of the biodegradable resin composition, For example, it may be included in 0.01 to 8% by weight, for example 0.01 to 5% by weight, for example 0.01 to 3% by weight, for example 0.01 to 2% by weight, or for example 0.05 to 1% by weight.

[생분해성 필름 및 이의 제조 방법][Biodegradable film and its manufacturing method]

According to one embodiment of the present invention, a biodegradable film formed from the biodegradable resin composition is provided.

Specifically, the biodegradable film is a biodegradable film containing a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin, based on the total weight of the biodegradable film, the poly It includes 40% to 99% by weight of a hydroxyalkanoate (PHA) resin and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin.

The PHA resin and the PBAT resin are as described above.

On the other hand, according to an embodiment of the present invention, 1) preparing a biodegradable pellet (pellet) containing a PHA resin and a PBAT resin; And 2) molding the biodegradable pellets; as a method for producing a biodegradable film, including, based on the total weight of the biodegradable film, the polyhydroxyalkanoate (PHA) resin in an amount of 40% to 40% by weight It provides a method for producing a biodegradable film comprising 99% by weight and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin.

Referring to FIG. 1 , the method of manufacturing the biodegradable film (S100) includes preparing a biodegradable pellet containing a PHA resin and a PBAT resin (S110).

The PHA resin and the PBAT resin are each as described above.

Meanwhile, the PHA resin and the PBAT resin may be mixed in the form of powder, granules, or pellets, respectively. Specifically, the PHA resin and the PBAT resin may each be in the form of pellets, and the biodegradable resin composition including them may also be in the form of pellets, biodegradable pellets.

That is, considering that the biodegradable resin composition according to the present invention is used as a masterbatch when preparing a biodegradable film, it is preferable to have a pellet form. The biodegradable resin composition in the form of a pellet may be prepared by mixing and melting the components constituting the same, and then pelletizing the extrudate while extruding through a twin screw extruder or the like.

Specifically, the biodegradable pellets are the PHA resin and the PBAT It can be prepared by melt-extruding a resin at 120°C to 200°C, or 140°C to 180°C.

In addition, according to the intended use and physical property design, the PHA resin and the PBAT The biodegradable pellets containing the resin may further include additives and/or biodegradable resins. The additive and the biodegradable resin are as described above.

In this case, the biodegradable pellets are the PHA resin, the PBAT It can be prepared by melt-extruding the resin, additives and/or biodegradable resin at 120°C to 200°C, or 140°C to 180°C.

The cutting step may be performed using any pellet cutting machine used in the art without limitation, and the pellets may have various shapes.

In addition, a step of drying the pellets may be further included. The drying may be performed at 40° C. to 100° C. for 2 hours to 12 hours. Specifically, the drying may be performed at 40 °C to 80 °C, or 50 °C to 90 °C for 3 hours to 10 hours or 4 hours to 8 hours. When the drying process conditions of the pellets satisfy the above range, the quality can be further improved.

Meanwhile, according to an embodiment of the present invention, the PHA resin may include a first PHA resin, a second PHA resin, or a mixed resin of the first PHA resin and the second PHA resin.

The types and specific characteristics of the first PHA resin and the second PHA resin are as described above.

According to an embodiment of the present invention, when the PHA resin includes a mixed resin of the first PHA resin and the second PHA resin, the first PHA resin, the second PHA resin, and the PBAT resin are melt-extruded to achieve biodegradability. Pellets can be formed.

The melt extrusion temperature of the PHA resin and the PBAT may be adjusted respectively.

Specifically, the extrusion temperature of the PHA resin and the extrusion temperature of the PBAT may be the same or different.

The extrusion temperature of the PHA resin may be, for example, 120 °C to 180 °C, eg 120 °C to 170 °C, or eg 125 °C to 160 °C.

The extrusion temperature of the PBAT resin may be, for example, 120°C to 180°C, 120°C to 170°C, or 125°C to 160°C.

When the extrusion temperatures of the PHA resin and the PBAT resin are different from each other, the extrusion temperature difference between them may be 20°C or less, 15°C or less, or 10°C or less.

In addition, after the melt extrusion, a heat treatment (heat setting) and/or drying step may be further included. As these process conditions, process conditions used in the present field can be used as long as the desired effects in the present invention are not impaired.

Referring back to FIG. 1 , the method of manufacturing the biodegradable film (S100) includes forming the biodegradable pellets (S120).

The molding may be performed by processing the biodegradable pellets into a desired shape and then cooling them to harden the shape and induce crystallization. Such shapes include, but are not limited to, fibers, filaments, films, sheets, rods, or other shapes. Such shaping may be extrusion molding, injection molding, compression molding, pressure molding, blowing or blow molding (eg blown film, blowing of foam), calendering, rotomolding, casting (eg cast sheet, cast film) or thermoforming. It may be performed using any method known in the art, such as (thermoforming).

In particular, according to an embodiment of the present invention, using the biodegradable composition is selected from the group consisting of a biodegradable bag, a biodegradable volume-based bag, a biodegradable shopping bag, a biodegradable plastic bag, a biodegradable zipper bag, and a biodegradable garbage bag When applied to biodegradable products containing one or more, the molding may be performed by blow molding.

Specifically, in the case of performing the blow molding, the blow molding conditions may vary depending on the use of the biodegradable product, and may be performed by various commonly used processes. For example, the biodegradable resin pellets may be blow molded at 120° C. to 150° C. using a blown film extruder.

In addition, the extrusion molding, injection molding, compression molding, pressure molding, or thermoforming may also be applied as needed.

In addition, the biodegradable resin composition according to an embodiment of the present invention can be provided in a form suitable for the intended use. For example, after providing the biodegradable resin composition in a pellet form, a sheet, film, coating, molded product, or biodegradable product is prepared, or a sheet, film, coating, molded product, or biodegradable product is directly prepared using the present composition. can be manufactured

[생분해성 필름의 물성][Physical properties of biodegradable film]

The biodegradable film according to an embodiment of the present invention can be biodegraded by any one of microorganisms, moisture, oxygen, light, and heat, and has excellent mechanical properties.

Specifically, the biodegradable film may have a tensile strength of, for example, 5 to 30 Mpa, 5 to 25 Mpa, 6 to 20 Mpa, or 6 to 15 Mpa, for example.

The tensile strength was measured by cutting the biodegradable film into a length of 100 mm and a width of 15 mm, and then using an INSTRON universal testing machine (4206-001, manufacturer: UTM) according to ASTM D 882 so that the gap between chucks was 50 mm, and tested at a room temperature of 25° C. at a tensile rate of 200 mm/min, and then the tensile strength was measured using a program built into the facility. When the tensile strength satisfies the above range, productivity, processability and formability of the biodegradable film may be simultaneously improved.

In addition, the biodegradable film may have elongation (elongation) of, for example, 100% to 600%, for example, 100% to 500%, for example, 150% to 450%, 200% to 450%, or, for example, 200% to 400%. The elongation was measured by cutting the biodegradable film into 4 cm in width and 1 cm in length, and using an INSTRON company's universal testing machine (4206-001, manufacturer: UTM) at a speed of 50 mm/min to the maximum immediately before breakage. After measuring the amount of deformation, the ratio of the maximum amount of deformation to the initial length was calculated as elongation.

Meanwhile, the biodegradable film may have a Rockwell hardness (R-hardness) of, for example, 80 to 120 HRC, for example, 90 to 120 HRC, for example, 90 to 10 HRC, or, for example, 90 to 100 HRC. The Rockwell hardness is a method of applying a certain force to the surface of the biodegradable film (sample) using an indenter, and then measuring the depth at which the indenter penetrates the surface of the biodegradable film and converting it into hardness. A diamond cone indenter may be used, and the final indentation depth due to permanent deformation may be measured by calculating the difference between the indentation depth by the initial load from the measured indentation depth.

Meanwhile, the biodegradable film may have excellent optical properties.

Specifically, the biodegradable film may have a haze of 20% or less, 15% or less, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, or 5% or less. If the haze exceeds the above-mentioned range, the transparency of the biodegradable film is significantly reduced, so there may be limitations in using it for packaging purposes in which the contents inside are visible. The haze is measured using a total light transmittance measurement method. The total light transmittance measurement method is a method of measuring both the diffuse transmittance due to diffusion and scattered transmission generated while a light source passes through a sample and the linear transmittance measured from parallel rays, and calculating the haze value by the difference in transmittance. It is a method.

In addition, the biodegradable film may have a light transmittance of 80% or more, 90% or more, 92% or more, or 93% or more. The light transmittance can be measured by the total light transmittance measurement method, and when using an ultraviolet spectrometer, the resultant value can be obtained from the transmittance at a wavelength of 550 nm.

The biodegradable film is characterized by excellent mechanical properties, particularly excellent strength and flexibility, and biodegradability to soil and ocean of 90% or more. The biodegradability is measured by collecting and continuously analyzing carbon dioxide generated under composting conditions and comparing the relative amount of carbon dioxide generated by decomposition of a standard material. Typically, cellulose is used as a standard material.

The biodegradability indicates the rate of decomposition compared to the standard material (eg, cellulose) in the same period. Specifically, the marine biodegradability measured according to the EL 724 standard is 90% or more.

The present invention will be described in more detail by the following examples. The following examples are merely illustrative of the present invention, and the scope of the present invention is not limited thereto.

<실시예><Example>

실시예 1Example 1

As shown in Table 1 below, the first PHA resin (3-HB-co-4-HB, aPHA) (CJ, Korea), the second PHA resin (3-HB-co-4-HB, scPHA) (CJ, Korea), polybutylene adipate terephthalate (PBAT) resin (Ankor bioplastics), and polyvinyl acetate-based additives were melt-extruded to obtain pellets. The melt extrusion was performed at about 160° C., and then cooled and cut with a pellet cutter to prepare pellets.

After drying the pellets at about 60° C. for about 8 hours, a biodegradable film was prepared by blow molding at a die temperature of about 130° C. under an extrusion speed of 200 rpm.

실시예 2Example 2

As shown in Table 1 below, a biodegradable film was prepared in the same manner as in Example 1, except that the polyvinyl acetate-based additive was not used.

실시예 3Example 3

As shown in Table 1 below, the first PHA resin (3-HB-co-4-HB, aPHA) and the PBAT resin were used without using the second PHA resin (3-HB-co-4-HB, scPHA). Except, a biodegradable film was prepared in the same manner as in Example 2.

실시예 4 Example 4

A biodegradable film was prepared in the same manner as in Example 1, except that the contents of the PHA and PBAT resins were changed as shown in Table 1 below.

비교예 1 Comparative Example 1

As shown in Table 1 below, the first PHA resin (3-HB-co-4-HB, aPHA) (CJ, Korea) and the second PHA resin (3-HB-co-4-HB, scPHA) (CJ, Korea) and a biodegradable film was prepared in the same manner as in Example 2, except that the PBAT resin was not used.

비교예 2 Comparative Example 2

A biodegradable film was prepared in the same manner as in Example 3, except that the contents of the first PHA resin (3-HB-co-4-HB, aPHA) and the PBAT resin were changed as shown in Table 1 below.

비교예 3Comparative Example 3

As shown in Table 1 below, a biodegradable film was prepared in the same manner as in Example 2, except that only the PBAT resin was used.

실험예Experimental example

실험예 1: 인장강도 Experimental Example 1: Tensile strength

After cutting the biodegradable film specimens prepared in the above Examples and Comparative Examples into 100 mm in length and 15 mm in width, in accordance with ASTM D 882, INSTRON's universal testing machine (4206-001, manufacturer: UTM) was used. After the test was performed at a room temperature of 25°C at a tensile speed of 200 mm/min, the tensile strength was measured using a program built into the equipment.

실험예 2: 신율 Experimental Example 2: Elongation

The biodegradable film specimens prepared in the above Examples and Comparative Examples were cut into 4 cm in width and 1 cm in length, and using an INSTRON universal testing machine (4206-001, manufacturer: UTM) at 50 mm/min After measuring the maximum strain immediately before fracture at the speed, the ratio of the maximum strain to the initial length was calculated as the elongation.

The tensile strength and elongation of the biodegradable films obtained in the above Examples and Comparative Examples are summarized in Table 1 below.

As can be seen in Table 1, the biodegradable films of Examples 1 to 4 were excellent in elongation and tensile strength. Furthermore, the biodegradable films of Examples 1 to 4 had excellent light transmittance and exhibited biodegradability in both soil and ocean.

Specifically, the biodegradable films of Examples 1 to 4 include 40 to 70% by weight of the PHA resin and 28 to 58% by weight of the PBAT resin, so that the tensile strength is about 6.02 to about 18.7 Mpa, and the elongation is about 6.02 to about 18.7 Mpa. It exhibited excellent flexibility while maintaining appropriate strength at about 230.1 to 400%.

On the other hand, since the film of Comparative Example 1 did not contain the PBAT resin and contained 100% by weight of the PHA resin, the elongation was about 28.7%, and the flexibility was significantly reduced.

In addition, the films of Comparative Examples 2 and 3 contain 70% to 100% by weight of the PBAT resin, so the elongation is significantly increased, but the biodegradability in soil and sea is poor or biodegradable compared to the films of Examples 1 to 4. is expected to take a long time.

On the other hand, in the case of the biodegradable films of Examples 1 and 2 containing the same amount of the PHA resin, it was confirmed that the physical properties were slightly different depending on the use of additives.

Specifically, the biodegradable film of Example 1 using the polyvinyl acetate-based additive had improved mechanical properties due to a higher increase in tensile strength and elongation compared to the biodegradable film of Example 2 without using the polyvinyl acetate-based additive.

Claims

A biodegradable resin composition comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin,

Based on the total weight of the biodegradable resin composition, 40% to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 1% by weight of the polybutylene adipate terephthalate (PBAT) resin A biodegradable resin composition containing 60% by weight.
According to claim 1,

The polyhydroxyalkanoate (PHA) resin is 3-hydroxybutyrate (3-HB), 3-hydroxypropionate (3-HP), 3-hydroxyvalerate (3-HV), 3- The group consisting of hydroxyhexanoate (3-HH), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV) and 6-hydroxyhexanoate (6-HH) A copolymerized polyhydroxyalkanoate resin comprising at least one repeating unit selected from, and a 4-hydroxybutyrate (4-HB) repeating unit, a biodegradable resin composition.
According to claim 1,

The weight ratio of the polyhydroxyalkanoate (PHA) resin and the polybutylene adipate terephthalate (PBAT) resin is 1: 0.01 to 1, the biodegradable resin composition.
According to claim 1,

The polyhydroxyalkanoate (PHA) resin includes a first PHA resin, a second PHA resin, or a mixed resin of the first PHA resin and the second PHA resin,

The first PHA resin includes 15% to 60% by weight of 4-hydroxybutyrate (4-HB) repeating units based on the total weight of the first PHA resin,

The second PHA resin contains 0.1% to 30% by weight of 4-hydroxybutyrate (4-HB) repeating units based on the total weight of the second PHA resin,

The first PHA resin and the second PHA resin have different contents of 4-HB repeating units, biodegradable resin composition.
According to claim 4,

Based on the total weight of the biodegradable resin composition,

1% to 50% by weight of the first PHA resin,

20% to 80% by weight of the second PHA resin, and

1% to 50% by weight of the polybutylene adipate terephthalate (PBAT) resin, a biodegradable resin composition.
According to claim 4,

The weight ratio of the first PHA resin and the second PHA resin is 1: 0.05 to 5, the biodegradable resin composition.
According to claim 4,

The first PHA resin has a glass transition temperature (Tg) of -45 ° C to -10 ° C,

The second PHA resin has at least one characteristic selected from a glass transition temperature (Tg) of -30 ° C to 80 ° C, a crystallization temperature (Tc) of 70 ° C to 120 ° C, and a melting temperature (Tm) of 100 ° C to 170 ° C satisfies,

The glass transition temperature (Tg) of the first PHA resin and the glass transition temperature (Tg) of the second PHA resin are different from each other, biodegradable resin composition.
According to claim 1,

The biodegradable resin composition is polybutylene succinate (PBS), polylactic acid (PLA), polybutylene adipate (PBA), polybutylene succinate-adipate (PBSA), polybutylene succinate-terephthalate (PBST), polyhydroxybutylate-valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT) and thermoplastic starch (TPS). A biodegradable resin composition further comprising a sexual resin.
According to claim 1,

The biodegradable resin composition further comprises at least one additive selected from the group consisting of an antioxidant, a compatibilizer, a weighting agent, a nucleating agent, a melt strength enhancer, and a slip agent,

The additive is contained in 0.1% to 30% by weight based on the total weight of the biodegradable resin composition, biodegradable resin composition.
A biodegradable film comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin,

Based on the total weight of the biodegradable film, 40% to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin A biodegradable film containing weight percent.
According to claim 10,

According to ASTM D 882, the tensile strength measured using a universal testing machine (UTM) is 5 to 30 MPa, and the elongation is 100 to 600%, a biodegradable film.
1) preparing a biodegradable pellet containing a polyhydroxyalkanoate (PHA) resin and a polybutylene adipate terephthalate (PBAT) resin; and

2) a method for producing a biodegradable film comprising the step of molding the biodegradable pellets,

Based on the total weight of the biodegradable film, 40% to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 60% by weight of the polybutylene adipate terephthalate (PBAT) resin Method for producing a biodegradable film containing weight percent.
According to claim 12,

The biodegradable pellets are prepared by melt-extruding the polyhydroxyalkanoate (PHA) resin, the polybutylene adipate terephthalate (PBAT) resin, and additives at 120 ° C to 200 ° C. Preparation of a biodegradable film method.
According to claim 12,

The polyhydroxyalkanoate (PHA) resin includes a first PHA resin, a second PHA resin, or a mixed resin of the first PHA resin and the second PHA resin,

The first PHA resin includes 15% to 60% by weight of 4-hydroxybutyrate (4-HB) repeating units based on the total weight of the first PHA resin,

The second PHA resin contains 0.1% by weight or more to 30% by weight of 4-hydroxybutyrate (4-HB) repeating units based on the total weight of the second PHA resin,

A method for producing a biodegradable film in which the content of 4-HB repeating units of the first PHA resin and the content of 4-HB repeating units of the second PHA resin are different from each other.
A biodegradable product formed from the biodegradable resin composition according to any one of claims 1 to 9.
According to claim 15,

The biodegradable product includes at least one selected from the group consisting of a biodegradable bag, a biodegradable volume-based bag, a biodegradable shopping bag, a biodegradable plastic bag, a biodegradable zipper bag, and a biodegradable garbage bag. Biodegradable product.