KR20210111185A - Biodegradable resin composition, biodegradable molded articles using same, and preperation method thereof - Google Patents

Abstract

The present invention relates to a biodegradable resin composition including a polyhydroxyalkanoate (PHA) resin and polybutylene succinate (PBS) resin, wherein the polyhydroxyalkanoate (PHA) resin is present in an amount of 40-99 wt%, and the polybutylene succinate (PBS) resin is present in an amount of 1-60 wt%, based on the total weight of the biodegradable resin composition. The present invention also relates to a biodegradable molded article obtained by using the composition and a method for manufacturing the same. The biodegradable resin composition having such a specific composition according to the present invention can improve the mechanical properties and optical properties of the biodegradable molded article formed from the composition at the same time and can be biodegraded in both soil and sea, and thus can be applied to various industrial fields, realizing excellent properties.

Description

Biodegradable resin composition, biodegradable molded article using same, and manufacturing method thereof

The present invention relates to a biodegradable resin composition, a biodegradable molded article using the same, and a method for manufacturing the same.

Currently commercialized general-purpose plastics have excellent physical properties, and demand is on the rise due to stable supply and price. It has become a factor causing serious environmental pollution problems.

In order to solve these environmental pollution problems, research on biodegradable plastics is being actively conducted in recent years.

Biodegradable plastic refers to a material that is decomposed into low-molecular substances by microorganisms in nature and finally decomposed into water and carbon dioxide, or water and methane gas.

Examples of this include polylactic acid (PLA), polybutyleneadipate terephthalate (PBAT), and polybutylene succinate (PBS), but it is difficult to actually biodegrade in various natural environments. Or, it must take a long time to be decomposed, and in particular, there is a limit to being completely biodegradable in the natural state of the sea and soil, and there is a need for research on biodegradable resins that can be applied to various fields by solving these problems.

For example, with the recent spread of delivery culture such as untact, disposable products such as containers for eating, straws, or cold cups; Electronic trays used for packaging as demand for electronic products increases; The use of biodegradable resins is required in various fields, such as fishing nets lost from fishing activities that account for more than half of marine debris.

However, in order to be applied to the above various uses, it must have excellent biodegradability in the sea and soil, as well as implement satisfactory flexibility, impact resistance and strength, and in particular, in order to be used as a food container or straw Excellent transparency is also required.

To this end, a film using a mixture of polylactic acid and polybutyleneadipate terephthalate (PBAT) is disclosed. However, in this case, since the compatibility of the two materials is insufficient, transparency is lowered, thermal properties are reduced, and it is difficult to simultaneously implement satisfactory flexibility, impact resistance, and strength.

Korean Patent Publication No. 2012-0103158

The present invention is devised to solve the problems of the prior art described above.

According to one embodiment, the present invention is to provide a biodegradable resin composition that is excellent in mechanical properties of tensile strength, elongation, flexibility and impact resistance and optical properties of light transmittance, and is biodegradable in both soil and sea at the same time.

According to another embodiment, the present invention is to provide a biodegradable molded article formed from the biodegradable resin composition and a method for manufacturing the same.

In order to achieve the above object, an embodiment is a biodegradable resin composition comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin, based on the total weight of the biodegradable resin composition , A biodegradable resin composition comprising 40 wt% to 99 wt% of the polyhydroxyalkanoate (PHA) resin, and 1 wt% to 60 wt% of the polybutylene succinate (PBS) resin do.

Another embodiment is a biodegradable molded article comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin, based on the total weight of the biodegradable molded article, the polyhydroxyal It provides a biodegradable molded article comprising 40 wt% to 99 wt% of canoate (PHA) resin, and 1 wt% to 60 wt% of the polybutylene succinate (PBS) resin.

Another embodiment comprises the steps of: 1) preparing a biodegradable pellet comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin; And 2) forming the biodegradable pellet; as a method for producing a biodegradable molded article comprising; based on the total weight of the biodegradable molded article, the polyhydroxyalkanoate (PHA) resin 40% by weight to It provides a method for producing a biodegradable molded article, including 99% by weight, including 1% to 60% by weight of the polybutylene succinate (PBS) resin.

The biodegradable resin composition according to an embodiment includes a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin, thereby providing optical properties of tensile strength, elongation, flexibility and impact resistance and optical transmittance. It is possible to provide a biodegradable sheet, film or molded article having excellent properties and biodegradable in both soil and sea.

Therefore, the biodegradable sheet, film or molded article formed from the biodegradable resin composition according to another embodiment can be variously applied to straws, eating containers, electronic product trays, fishing nets, and cold cups, and to preserve the environment with excellent physical properties. can work effectively on

1 is a flowchart illustrating a manufacturing process of a biodegradable molded article according to an embodiment of the present invention.

Hereinafter, the invention will be described in detail through embodiments. The embodiments are not limited to the contents 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.

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

In this specification, terms such as first, second, 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.

[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 succinate (PBS) resin, the total weight of the biodegradable resin composition Based on the polyhydroxyalkanoate (PHA) resin containing 40% to 99% by weight, and the polybutylene succinate (PBS) resin is included in 1% to 60% by weight.

As the biodegradable resin composition has the above specific composition, the mechanical properties of tensile strength, elongation, flexibility and impact resistance and optical properties of light transmittance can be simultaneously improved, and the biodegradable molded article formed therefrom is biodegradable in both soil and sea. As a result, it can be applied to more diverse fields and exhibit excellent properties.

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

Polyhydroxyalkanoate (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), polybutylene succinate adipate (PBSA) derived from conventional petroleum. ), etc., with similar physical properties to synthetic polymers, complete biodegradability, and excellent biocompatibility.

Specifically, the PHA resin is a thermoplastic natural polyester polymer that accumulates in microbial cells, can be composted into 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 biodegradable in soil and sea, when the biodegradable resin composition includes the PHA resin, it is biodegradable in any environmental conditions, such as soil and sea, and has environmentally friendly properties. Therefore, the biodegradable molded article formed by using the biodegradable resin composition including the PHA resin can be utilized in various fields as an eco-friendly product.

The PHA resin may be formed by enzymatically polymerizing one or more repeating monomer units in living cells.

The PHA resin may be a copolymerized polyhydroxyalkanoate resin (hereinafter referred to as a PHA copolymer), 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 the repeating unit 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 Roxydecanoate (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 them.

Specifically, the PHA resin comprises at least one repeating unit 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 a 4-HB repeating unit. That is, the PHA resin may be a PHA copolymer 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 PHA copolymer further comprising a repeating unit.

According to an embodiment of the present invention, the PHA resin is at least one repeating unit 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 comprising a 4-HB repeating unit.

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, 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 PHA resin may be a copolymerized polyhydroxyalkanoate resin including 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 an 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 enhance biodegradability of soil and sea, and to realize excellent physical properties of improved optical properties, thermal properties, and mechanical properties, the 4- The content of HB repeat units can be important.

More specifically, the PHA copolymer may include 0.1 wt% to 60 wt% of the 4-HB repeating unit based on the total weight of the PHA copolymer. For example, the content of the 4-HB repeating unit may be, 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 enhanced, excellent optical properties are maintained, thermal properties of the material are improved, and mechanical properties such as flexibility and strength are further improved. can be improved

In addition, 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. That is, the PHA resin may be a PHA copolymer with controlled crystallinity.

The crystallinity-controlled PHA resin may have crystallinity and amorphous properties adjusted by increasing molecular structure irregularities, specifically, by controlling the type of monomer, the ratio of the monomer, or the type and/or content of the isomer. can

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

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.

On the other hand, the PHA copolymer may contain, for example, 20 wt% or more, 35 wt% or more, 40 wt% or more, 50 wt% or more, 60 wt% or more of 3-HB repeating units based on the total weight of the PHA copolymer. , 70 wt% 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% 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.

Meanwhile, 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. °C, -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 PHA resin may have, for example, a crystallization temperature (Tc) that cannot be measured, 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 It may be 110°C.

The PHA resin may have, for example, a melting temperature (Tm) that cannot be measured, or may be, for example, 100°C to 170°C, such as 110°C to 150°C, or for example 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 content of the 4-HB repeating unit, the glass transition temperature (Tg), the crystallization temperature (Tc), and the melting temperature (Tm) of the first PHA resin and the second PHA resin may be different from each other.

Specifically, the first PHA resin comprises, for example, 15 wt% to 60 wt%, 15 wt% to 55 wt%, 20 wt% to 55 wt%, 25 wt% to 55 wt% of the 4-HB repeating unit. wt%, 30 wt% to 55 wt%, 35 wt% to 55 wt%, 20 wt% to 50 wt%, 25 wt% to 50 wt%, 30 wt% to 50 wt%, 35 wt% to 50 wt% Or 20 wt% to 40 wt% may be included.

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 - It may be 30 °C to -20 °C.

The first PHA resin may have, for example, a crystallization temperature (Tc) that cannot be measured, 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 cannot be measured, 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, 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 wt% to 30 wt%. For example, the second PHA resin may contain, for example, 0.1 wt% to 30 wt%, 0.5 wt% to 30 wt%, 1 wt% to 30 wt%, 3 wt% to 30 wt% of the 4-HB repeating unit. , 1% to 28%, 1% to 25%, 1% to 24%, 1% to 20%, 1% to 15%, 2% to 25%, 3 wt% to 25 wt%, 3 wt% to 24 wt%, 5 wt% to 24 wt%, 5 wt% to 20 wt%, greater than 5 wt% to less than 20 wt%, 7 wt% to 20 wt%, 10 It may be included in an amount of 20 wt% to 20 wt%, 15 wt% to 25 wt% or 15 wt% to 24 wt%.

The content of the 4-HB repeating unit may be different in the first PHA resin and the second PHA resin.

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.

A glass transition temperature (Tg) of the first PHA resin and a 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, or, for example, 75°C to 115°C, or, for example, may not be 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 or, for example, 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, may be.

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 At least one characteristic selected from a crystallization temperature (Tc) of °C and a melting temperature (Tm) of 120 °C to 160 °C is satisfied, and the glass transition temperature (Tg) of the first PHA resin and the glass of the second PHA resin The transition temperatures Tg may be different from each other. In addition, the crystallization temperature (Tc) and the 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 of a 4-HB repeating unit, a glass transition temperature (Tg), a crystallization temperature (Tc), and a melting temperature (Tm) in the above ranges, 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 be PHA resins having a degree of crystallinity (crystallinity) adjusted.

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 an scPHA resin). can

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

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

The glass transition temperature (Tg) of the aPHA resin may be, for example, -35° 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, for example, 1 to 25% by weight of less than 1 to 25% by weight based on the total weight of the PHA resin.

The glass transition temperature (Tg) of the scPHA resin may be -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 may include, for example, 40 to 99% by weight of the PHA resin based on the total weight of the biodegradable resin composition. For example, 50 to 95% by weight, 40 to 80% by weight, 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 or more. and 99 wt% or less, 95 wt% or less, 90 wt% or less, 85 wt% or less, or 80 wt% or less.

The PHA resin included in the biodegradable resin composition may be selected within the above range depending on the intended use. For example, when the biodegradable resin is applied to disposable products such as straws or containers for eating, the The PHA resin may include 40 wt% or more, specifically 50 wt% or more, and in this case, it is advantageous in terms of biodegradability. As another example, when the biodegradable resin is applied to a fishing net, the PHA resin may be included in 70 wt% or more, and in this case, the biodegradation effect is very good in both soil and the sea, and in particular, the marine biodegradability is excellent. .

On the other hand, when the PHA resin includes the first PHA resin, for example, 1 wt% to 95 wt% 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, for example, in an amount of 5 to 80% by weight. Specifically, the first PHA resin may be included in an amount of 10 wt% or more and 40 wt% or less.

In another example, when the first PHA resin is mixed with the second PHA resin, the first PHA resin is, for example, 1 to 50% by weight, for example 10 to 40% by weight, or, for example, For example, it may be included in an amount of 20 to 40% by weight.

When the PHA resin includes the second PHA resin, for example, 1 wt% to 95 wt% may be used, and when the second PHA resin is used alone, based on the total weight of the biodegradable resin composition, The second PHA resin may be included, for example, in an amount of 50 to 95% by weight. Specifically, the second PHA resin may include 50 wt% or more, 55 wt% or more, 60 wt% or more, 65 wt% or more, or 70 wt% or more, 95 wt% or less, 90 wt% or less, 85 wt% or more It may contain less than or equal to 80% by weight, or less than or equal to 80% by weight.

As another example, when the second PHA resin is mixed with the first PHA resin and used, the second PHA resin may include, for example, 20 to 80% by weight, or, for example, 30 to 70% by weight. can

For example, the biodegradable resin composition may include 1 wt% to 50 wt% of the first PHA resin, 20 wt% to 80 wt% of the second PHA resin, and the poly Butylenesuccinate (PBS) resin may include 1% to 50% by weight.

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 from 1:0.5 to 4, or for example from 1:1.2 to 4.

When each content of the PHA resin, or the first PHA resin and the second PHA resin, and their content ratios are satisfied within the above ranges, optical properties, thermal properties, and mechanical properties can be further improved, and biodegradation When manufacturing a cast molded article, moldability, processability, and productivity can also be improved.

polybutylene succinate ( PBS ) profit

The biodegradable resin composition according to an embodiment of the present invention includes polybutylene succinate (hereinafter referred to as PBS) resin.

The PBS resin is a representative polycondensation aliphatic polyester, and the PBS is a heat-resistant polymer having a relatively higher melting point than other polyesters synthesized from dihydric alcohols and dihydric acids.

Specifically, the PBS resin is biodegradable, synthesized by polycondensation by esterification of 1,4-butanediol (1,4-BDO) with succinic acid, and transesterification of the oligomers thus generated. It is bioplastic.

By including the PBS resin in the biodegradable resin composition according to an embodiment of the present invention, it is environmentally friendly because it can be naturally decomposed by microorganisms, etc., and the breaking strength, tensile strength, elongation (elongation), optical properties, hardness, melting Mechanical properties such as melt strength and water resistance may be improved, and in particular, tensile strength and elongation (elongation) may be improved to improve flexibility while maintaining appropriate strength.

If the PHA resin is used alone, since the PHA resin has low crystallinity and can be given softness, mechanical properties such as tensile strength and hardness are lowered due to the limitations of these physical properties, and, thereby, the product Its use may be very limited because it is not suitable for molding or the productivity is very low.

In addition, the PBS 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 PBS resin has this molecular weight range, compatibility and processability with the PHA resin may be more excellent, and the biodegradable resin composition of one embodiment may exhibit improved mechanical properties, etc. according to a relatively high molecular weight. . In addition, by this molecular weight range, transparency of the resin composition and the sheet/film or biodegradable molded article formed therefrom may also be excellently maintained.

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

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

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

Meanwhile, the biodegradable composition according to an embodiment of the present invention may include the PHA resin and the PBS resin in a weight ratio of 1: 0.01 to 1, 1: 0.10 to 0.6, or 1: 0.01 to 0.4 by weight.

When the weight ratio of the PHA resin and the PBS resin satisfies the content ratio, optical properties, molding properties, and mechanical properties can be further improved, and biodegradability, processability and productivity can also be improved when manufacturing a molded article.

biodegradable 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 molded article or article manufactured using the same, and 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 biodegradable resin is not particularly limited as long as it is commonly used, and representative biodegradable resins are polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene adipate (PBA). , polybutylene succinate-adipate (PBSA), polybutylene succinate-terephthalate (PBST), polyhydroxybutylate-valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate It may include at least one selected from the group consisting of pate terephthalate (PBSAT) and thermoplastic starch (TPS). Specifically, the biodegradable resin may include at least one selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), and thermoplastic starch (TPS). More specifically, the biodegradable resin may include at least one selected from the group consisting of polybutylene adipate terephthalate (PBAT) 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, mechanical properties can be achieved to be suitable for various uses of the biodegradable molded article, and thus there is an advantage that it can be used in various ways. That is, since the biodegradable resin composition further includes the biodegradable resin, tensile strength and elongation may be further improved.

additive

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

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

The additive may be 0.1 wt% or more, 0.5 wt% or more, 1 wt% or more, 1.5 wt% or more, or 2 wt% or more. 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 to prevent decomposition by ozone or oxygen or to prevent oxidation during storage, and to prevent deterioration of physical properties of a sheet/film or biodegradable molded article formed from the biodegradable resin composition.

As long as the antioxidant does not impair the effects of the present invention, a commonly used antioxidant may be used.

Specifically, the antioxidant may include at least one selected from the group consisting of hindered phenolic 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 It may include one or more selected.

The phosphite-based (phosphorus-based) 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 may include one or more selected from the group consisting of.

The antioxidant may be included in an amount of 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 content range, the physical properties of the sheet/film or biodegradable molded article formed from the biodegradable composition may be improved, and it may be more advantageous to achieve the desired effect in the present invention.

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

As long as the compatibilizer does not impair the effects of the present invention, a commonly used compatibilizer may be used.

Specifically, the compatibilizer is made of polyvinyl acetate (PVAc), isocyanate, polypropylene carbonate, glycidyl methacrylate, ethylene vinyl alcohol, polyvinyl alcohol (PVA), ethylene vinyl acetate, and maleic anhydride. It may include 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, 0.01 to 5% by weight, for example, 0.1 to 4.5% by weight, for example, 0.1 to 3% by weight, or, for example, may be included in 0.1 to 2% by weight.

When the compatibilizer satisfies the above content range, it is possible to improve the physical properties of the sheet/film or biodegradable molded article formed from the biodegradable composition by increasing the compatibility between the resins used, and to achieve the desired effect in the present invention. may be more advantageous for

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

As long as the weight agent does not impair the effects of the present invention, a commonly used inorganic material may be used.

Specifically, the weight 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 fiber. may include.

The weight agent may have an average particle size of 0.5 μm to 10 μm. When the average particle size of the weight agent is less than 0.5 μm, dispersion of the particles becomes difficult, and when it exceeds 10 μm, the size of the particles becomes excessively large, which may impair the effects of the present invention.

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

When the weight 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 to aid or change the crystallization morphology of the polymer when the polymer melt is cooled and to improve the solidification rate. 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 in the present invention can be efficiently achieved.

As long as the nucleating agent does not impair the effects of the present invention, a conventionally used nucleating agent may be used.

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 salt, 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, organic phosphorus metal salts and boron nitride; Low molecular weight organic compounds having a metal carboxylate group, for example, 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 of phthalic acid monomethyl ester; Polymeric organic compounds having metal carboxylate groups, for example, carboxyl group-containing polyethylene obtained by oxidation of polyethylene, carboxyl group-containing polypropylene obtained by oxidation of polypropylene, acrylic acid or methacrylic acid and olefins ( For example, a copolymer of ethylene, propylene and butene-1), a copolymer of acrylic acid or methacrylic acid and styrene, a copolymer of olefin and maleic anhydride, and a copolymer of styrene and maleic anhydride; metal salts of each; Polymeric organic compounds, for example, alpha-olefins branched to the third carbon atom and having 5 or more carbon atoms (eg, 3,3 dimethylbutene-1,3-methylbutene-1,3-methylpentene-1) ,3-methylhexene-1 and 3,5,5-trimethylhexene-1), polymers of vinylcycloalkanes (such as vinylcyclopentane, vinylcyclohexane and vinylnorbornane), polyalkylene glycols (such as polyethylene glycol) and polypropylene glycol), poly(glycolic acid), cellulose, cellulose esters and cellulose ethers; Phosphoric or phosphorous acid and metal salts thereof, such as metal salts of diphenyl phosphate, diphenyl phosphite, 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. The nucleating agents may be used alone or in combination with each other.

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

When the nucleating agent satisfies the content range, the solidification rate is improved to improve the moldability, and for example, when cutting for pellet production, or in the manufacturing process, the solidification rate is improved to improve productivity and Processability can be further improved.

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

As long as the melt strength enhancer does not impair the effects of the present invention, a conventionally used melt strength enhancer may be used.

Specifically, the melt strength enhancer is polyester, styrenic polymer (such as acrylonitrile butadiene styrene and polystyrene), polysiloxane, organomodified 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 may be included in an amount of 0.01 to 10% by weight, 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.

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 the slip property (slippery property) during extrusion and preventing the sheet or film surfaces from sticking together during the process.

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

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, such as 0.01 to 5% by weight, such as 0.2 to 4.5% by weight, such as 0.2 to 3% by weight, or for example 0.2 to 1% by weight.

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

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

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

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

The crosslinking 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, for example, based on the total weight of the biodegradable resin composition For example, 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, may be included in 0.05 to 1% by weight.

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 one selected from the group consisting of trimethyl phosphate, triphenyl phosphate, trimethyl phosphine, 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, 0.01 to 8% by weight, such as 0.01 to 5% by weight, such as 0.01 to 3% by weight, such as 0.01 to 2% by weight, or for example 0.05 to 1% by weight.

[Biodegradable molded article and manufacturing method thereof]

According to an embodiment of the present invention, there is provided a biodegradable molded article formed from the biodegradable resin composition.

Specifically, the biodegradable molded article is a biodegradable molded article comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin, based on the total weight of the biodegradable molded article, the polyhydroxy 40 wt% to 99 wt% of the alkanoate (PHA) resin, and 1 wt% to 60 wt% of the polybutylene succinate (PBS) resin.

The PHA resin and the PBS resin are the same as described above.

On the other hand, according to an embodiment of the present invention, 1) preparing a biodegradable pellet (pellet) comprising a PHA resin and a PBS resin; And 2) forming the biodegradable pellet; as a method for producing a biodegradable molded article comprising; based on the total weight of the biodegradable molded article, the polyhydroxyalkanoate (PHA) resin 40% by weight to It provides a method for producing a biodegradable molded article, including 99% by weight, including 1% to 60% by weight of the polybutylene succinate (PBS) resin.

Referring to Figure 1, the manufacturing method (S100) of the biodegradable molded article includes a step (S110) of preparing a biodegradable pellet comprising a PHA resin and a PBS resin.

The PHA resin and the PBS resin are the same as described above, respectively.

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

That is, the biodegradable resin composition according to the present invention is preferably in the form of a pellet, considering that it is used as a master batch when manufacturing a biodegradable sheet/film or a biodegradable molded article. The biodegradable resin composition in the form of pellets can be prepared by mixing and melting the components constituting the same, and then pelletizing the extrudate while extruding, for example, through a twin-screw extruder.

Specifically, the biodegradable pellet is the PHA resin and the PBS It can be prepared by melt-extruding the resin at 120°C to 200°C or 140°C to 180°C.

In addition, depending on the intended use and design of physical properties, the PHA resin and the PBS The biodegradable pellets comprising the resin may further contain additives and/or biodegradable resins. The additive and the biodegradable resin are the same as described above.

In this case, the biodegradable pellet is the PHA resin, the PBS It may be prepared by melt-extruding the resin, additive and/or biodegradable resin at 120°C to 200°C or 140°C to 180°C.

The cutting step may be performed without limitation as long as it is a pellet cutter used in the art, and the pellets may have various shapes.

In addition, it may further include the step of drying after preparing the pellet. 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 the same as described above.

According to an embodiment of the present invention, when a mixed resin of the first PHA resin and the second PHA resin is included as the PHA resin, the first PHA resin, the second PHA resin, and the PBS resin are melt-extruded and biodegradable. Pellets can be formed.

Melt extrusion temperatures of the PHA resin and the PBS may be adjusted, respectively.

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

The extrusion temperature of the PHA resin may be, for example, 120°C to 180°C, for example 120°C to 160°C, or, for example, 125°C to 155°C.

The extrusion temperature of the PBS resin may be, for example, 120 °C to 180 °C, for example 120 °C to 160 °C, or, for example, 125 °C to 155 °C.

When the extrusion temperature of the PHA resin and the PBS is different from each other, the extrusion temperature difference may be 20° C. or less, 15° C. or less, or 10° C. or less.

In addition, after the melt extrusion, heat treatment (heat setting) and/or drying step may be further included. As long as these process conditions do not impair the desired effect in the present invention, the process conditions used in this field may be used.

Referring back to FIG. 1 , the manufacturing method ( S100 ) of the biodegradable molded article includes the step ( S120 ) of molding the biodegradable pellets.

The molding process the biodegradable pellets into a desired shape and then cools them, so that the shape hardens and crystallization can be induced. Such shapes include, but are not limited to, fibers, filaments, films, sheets, rods, or other shapes. Such molding may include extrusion molding, injection molding, compression molding, air pressure molding, blowing or blow molding (eg blown film, blowing of foam), calendering, rotational molding, casting (eg cast sheet, cast film) or thermoforming. It can be performed using any method known in the art, such as (thermoforming).

For example, the extrusion molding conditions may vary depending on the use of the biodegradable molded article, and the extrusion may be performed by a commonly used process. For example, extrusion may be performed at 130 to 180° C. using a twin-screw extruder, and extrusion may be performed at 140 to 160° C. using a single-screw extruder.

Specifically, when the biodegradable molded article is a straw, the difference between the inner diameter and the outer diameter of the die is measured, for example, 0.1 to 3 mm using a ring die after manufacturing in a biodegradable sheet form using the biodegradable resin composition. can be extrusion-molded. In addition, in order to provide various functions, for example, a molding and post-processing process such as a wrinkle or a periwinkle shape may be further added.

For example, the injection molding conditions may vary depending on the use of the biodegradable molded article, and the injection molding may be performed by a commonly used process. For example, injection molding may be performed at 160 to 180°C.

The biodegradable molded article may be applied in various ways, for example, the biodegradable molded article may include at least one selected from the group consisting of straws, eating containers, electronic product trays, fishing nets, and cold cups.

Specifically, the biodegradable article may include at least one selected from the group consisting of straws, containers, cups, cold cups, spoons, forks, knives, electronic product trays, fishing nets, and bottles.

In addition, the biodegradable resin composition according to an embodiment of the present invention may be provided in a form suitable for a desired use. For example, after providing the biodegradable resin composition in the form of pellets, a sheet, film, coating, molded article or biodegradable article is prepared, or a sheet, film, coating, molded article and biodegradable article are prepared immediately using the composition. can be manufactured.

[Physical properties of biodegradable molded products]

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

Specifically, the biodegradable molded article may have a tensile strength of, for example, 5 to 40 Mpa, 10 to 35 Mpa, or 10 to 30 Mpa.

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

In addition, the biodegradable molded article may have an elongation (elongation) of, for example, 100% to 600%, such as 100% to 500%, such as 120% to 450%, or, for example, 150% to 450%. The elongation was measured by cutting the biodegradable molded article (film specimen) into 4 cm in width and 1 cm in length, and using a universal testing machine (4206-001, manufacturer: UTM) of INSTRON at a speed of 50 mm/min. After measuring the maximum amount of deformation immediately before fracture, the ratio of the maximum amount of deformation to the initial length was calculated as the elongation.

On the other hand, the biodegradable molded article may have a Rockwell hardness (R-hardness) of, for example, 80 to 120HRC, such as 90 to 120HRC, such as 90 to 10HRC, or, for example, 90 to 100HRC.

On the other hand, the biodegradable molded article may have excellent optical properties.

Specifically, the biodegradable molded article may have a haze of 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 molded product is significantly reduced, and there may be a limitation in using it for packaging purposes in which the contents inside are visible.

In addition, the biodegradable molded article may have a light transmittance of 80% or more, 90% or more, 92% or more, or 93% or more.

The biodegradable molded article is characterized in that it has excellent mechanical properties, particularly strength and flexibility, and has a biodegradability of 90% or more for soil and sea.

The biodegradability indicates the ratio of decomposition compared to the standard material (eg, cellulose) in the same period, and the Ministry of Environment of the Republic of Korea defines it as a biodegradable material when the biodegradability is 90% or more compared to the standard material. Specifically, the marine biodegradability measured according to the EL 724 standard is 90% or more.

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>

Example 1

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

After drying the pellets at about 60° C. for about 8 hours, extrusion molding was performed at about 170° C. using a twin-screw T-die extruder to prepare a biodegradable molded article.

Example 2

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

Example 3

As shown in Table 1 below, the second PHA resin (3-HB-co-4-HB, scPHA) was not used, and only the first PHA resin (3-HB-co-4-HB, aPHA) and PBS resin were used. Except that, a biodegradable molded article was prepared in the same manner as in Example 2.

Example 4

A biodegradable molded article was prepared in the same manner as in Example 1, except that the content of PHA and PBS resin was changed as shown in Table 1 below.

Comparative Example 1

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

Comparative Example 2

A biodegradable molded article 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 PBS resin were changed as shown in Table 1 below.

Experimental example

Experimental Example 1: Tensile Strength

After cutting the biodegradable molded article specimen (film specimen) prepared in the Examples and Comparative Examples to a length of 100 mm and a width of 15 mm, according to ASTM D 882, INSTRON’s universal testing machine (4206-001, manufacturer: UTM) was used to install the chuck so that the distance between chucks was 50 mm, and after testing at a room temperature of 25°C at a tensile rate of 200 mm/min, the tensile strength was measured with a program built into the facility.

Experimental Example 2: Elongation

The biodegradable molded product specimen (film specimen) prepared in the Examples and Comparative Examples was cut into 4 cm in width and 1 cm in length, and 50 using a universal tester (4206-001, manufacturer: UTM) of INSTRON. After measuring the maximum amount of deformation just before fracture at a speed of mm/min, the ratio of the maximum amount of deformation to the initial length was calculated as the elongation.

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

As can be seen in Table 1, the biodegradable molded articles of Examples 1 to 4 were very excellent in elongation and tensile strength compared to the molded articles of Comparative Examples 1 and 2. Furthermore, the biodegradable films of Examples 1 to 4 had excellent light transmittance and exhibited biodegradability in both soil and sea.

Specifically, the biodegradable molded articles of Examples 1 to 4 contain 40% to 70% by weight of PHA resin and 28 to 58% by weight of PBS resin, so that the tensile strength is about 9 to about 22.6 Mpa, and the elongation is It exhibited excellent flexibility while maintaining an appropriate strength at about 121.3 to 262.3%.

On the other hand, the molded article of Comparative Example 1 did not contain the PBS resin but contained 100% by weight of the PHA resin, so that the elongation was about 28.7%, and the flexibility was significantly reduced.

In addition, it is predicted that the molded article of Comparative Example 2 has poor biodegradability in soil and sea compared to the molded articles of Examples 1 to 4 or requires a long time to be biodegradable.

On the other hand, in the case of the biodegradable molded articles of Examples 1 and 2 containing the same amount of the PHA resin, it was confirmed that the physical properties were changed according to the use of the additive.

Specifically, the biodegradable molded article of Example 1 using the polyvinyl acetate-based additive has higher tensile strength and elongation compared to the biodegradable molded article of Example 2 that does not use the polyvinyl acetate-based additive, so that it has adequate strength and flexibility This was further improved.

Claims (16)

A biodegradable resin composition comprising a polyhydroxyalkanoate (PHA) resin and a polybutylenesuccinate (PBS) resin, comprising:
Based on the total weight of the biodegradable resin composition, 40 to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 60% by weight of the polybutylene succinate (PBS) resin % comprising, a biodegradable resin composition.
The method of 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 biodegradable resin composition, which is a copolymerized polyhydroxyalkanoate resin comprising one or more repeating units selected from, and 4-hydroxybutyrate (4-HB) repeating units.
The method of claim 1,
The weight ratio of the polyhydroxyalkanoate (PHA) resin and the polybutylenesuccinate (PBS) resin is 1: 0.01 to 1, the biodegradable resin composition.
The method of claim 1,
The polyhydroxyalkanoate (PHA) resin comprises 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 comprises 15 to 60% by weight of 4-hydroxybutyrate (4-HB) repeating unit based on the total weight of the first PHA resin,
The second PHA resin contains 4-hydroxybutyrate (4-HB) repeating units in an amount of 0.1 wt% to 30 wt% based on the total weight of the second PHA resin,
The first PHA resin and the second PHA resin have a content of 4-HB repeating unit different from each other, biodegradable resin composition.
5. The method of 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
The polybutylene succinate (PBS) resin of 1% to 50% by weight, biodegradable resin composition.
5. The method of 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.
5. The method of claim 4,
The first PHA resin has a glass transition temperature (Tg) of -45 ℃ to -10 ℃,
The second PHA resin has at least one property 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. satisfied with
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.
The method of claim 1,
The biodegradable resin composition is polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene adipate (PBA), polybutylene succinate-adipate (PBSA), polybutylene succinate- One selected from the group consisting of terephthalate (PBST), polyhydroxybutylate-valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT) and thermoplastic starch (TPS) A biodegradable resin composition further comprising the above biodegradable resin.
The method of claim 1,
The biodegradable resin composition further comprises one or more additives selected from the group consisting of antioxidants, compatibilizers, weight agents, nucleating agents, melt strength enhancers, and slip agents,
The additive is included in an amount of 0.1% to 30% by weight based on the total weight of the biodegradable resin composition, biodegradable resin composition.
A biodegradable molded article comprising a polyhydroxyalkanoate (PHA) resin and a polybutylenesuccinate (PBS) resin,
Based on the total weight of the biodegradable molded article, 40 to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 60% by weight of the polybutylenesuccinate (PBS) resin comprising, a biodegradable molded article.
11. The method of claim 10,
In accordance with ASTM D 882, the tensile strength measured using a universal testing machine (UTM) is 5 to 40 MPa, and the elongation is 100 to 600%, a biodegradable molded article.
11. The method of claim 10,
The biodegradable molded article comprising at least one selected from the group consisting of straws, eating containers, electronic product trays, fishing nets, and cold cups, biodegradable molded articles.
1) preparing a biodegradable pellet comprising a polyhydroxyalkanoate (PHA) resin and a polybutylene succinate (PBS) resin; and
2) forming the biodegradable pellet; as a method for producing a biodegradable molded article comprising,
Based on the total weight of the biodegradable molded article, 40 to 99% by weight of the polyhydroxyalkanoate (PHA) resin, and 1% to 60% by weight of the polybutylenesuccinate (PBS) resin Including, a method for producing a biodegradable molded article.
14. The method of claim 13,
The biodegradable pellets are produced by melt-extruding the polyhydroxyalkanoate (PHA) resin, the polybutylene succinate (PBS) resin, and additives at 120°C to 200°C, a method of manufacturing a biodegradable molded article.
14. The method of claim 13,
Wherein the molding comprises at least one molding process selected from the group consisting of extrusion molding, injection molding, compression molding, air pressure molding, blowing or blow molding, and thermoforming, a method for producing a biodegradable molded article.
14. The method of claim 13,
The polyhydroxyalkanoate (PHA) resin comprises 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 comprises 15 to 60% by weight of 4-hydroxybutyrate (4-HB) repeating unit based on the total weight of the first PHA resin,
The second PHA resin contains 4-hydroxybutyrate (4-HB) repeating units in an amount of 0.1 wt% or more to 30 wt% based on the total weight of the second PHA resin,
A method for producing a biodegradable molded article, wherein the content of the 4-HB repeating unit of the first PHA resin and the content of the 4-HB repeating unit of the second PHA resin are different from each other

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