Vaporization promoter for polylactic acid resin and composition containing said promoter

Abstract

One embodiment of the present disclosure is a composition comprising at least 10% by weight to less than 100% by weight of a polylactic acid (PLA) resin based on the total weight of the composition, and having a vaporization degree (V) of 50% or more obtained by measuring the cumulative amount of carbon dioxide (CO2) generated over 10 weeks at 30°C. 10w The present invention relates to a composition having the above-mentioned amine group and a vaporization promoter for polylactic acid (PLA) resin for promoting the vaporization of polylactic acid (PLA) resin. The vaporization promoter for polylactic acid (PLA) resin can significantly accelerate the vaporization of polylactic acid (PLA) resin, which has a low vaporization degree at room temperature of 30°C, and therefore improves the biodegradation effect of polylactic acid (PLA).

Description

[Technical field]

[0001] The present disclosure relates to a vaporization promoter that promotes the vaporization of a polylactic acid resin, and a composition containing the vaporization promoter. [Background technology]

[0002] The demand for currently commercialized general-purpose plastics is increasing due to their excellent physical properties and stable supply and price. However, the problem of disposing of waste plastics occurs throughout our lives. Because waste plastics do not decompose under natural conditions such as in the ocean and soil, they are a factor that causes serious environmental pollution problems.

[0003] In order to solve these environmental pollution problems, biodegradable plastics have been actively researched in recent years.

[0004] Biodegradable plastics are materials that can be broken down by microorganisms present in nature into low molecular weight substances and ultimately into water and carbon dioxide, or water and methane gas.

[0005] Polylactic acid resin, which is usually used as such a biodegradable plastic, is a biodegradable thermoplastic polyester that has great potential to replace conventional petrochemical polymers. It is the most researched renewable polymer material to date, and its applications are being actively developed.

[0006] Polylactic acid resin has the property of being able to decompose rapidly under certain composting conditions to regenerate carbon dioxide (CO2), but the specific composting conditions required for polylactic acid resin to decompose and generate carbon dioxide are very harsh.

[0007] Specifically, polylactic acid resin naturally decomposes in soil containing many microorganisms at high temperatures of 50°C or higher and high humidity of about 40%, eventually generating carbon dioxide. It is problematic in that it is hardly biodegradable at room temperature and takes a long time to decompose under natural conditions such as in the ocean or soil.

[0008] To solve this problem, an artificial biodegradation environment can be created, but maintaining certain composting (biodegradation) conditions requires high costs and sufficient oxygen supply, so there is still a significant limit to increasing the decomposition rate of polylactic acid resin.

[0009] [Prior art document] [Patent documents] (Patent Document 1) Korean Patent Application Publication No. 2014-0112200 Summary of the Invention [Problem to be solved by the invention]

[0010] The present disclosure has been devised to solve the problems of the prior art discussed above.

[0011] The present disclosure aims to provide a vaporization promoter for polylactic acid resin (PLA) that increases the vaporization degree of polylactic acid resin (PLA), which has a low vaporization degree at room temperature of 30°C, thereby accelerating the biodegradation effect (speed) of polylactic acid resin (PLA) even at room temperature, and a composition containing the promoter. [Means for solving the problem]

[0012] According to one embodiment of the present disclosure, a composition includes a polylactic acid (PLA) resin in an amount ranging from 10% by weight to less than 100% by weight based on the total weight of the composition, and when a cumulative amount of carbon dioxide (CO2) generated over a period of 10 weeks at 30°C is measured according to ISO14855, the degree of vaporization (V) represented by the following formula 1 is obtained. 10w ) is 50% or more: [Formula 1]

number

[0013] In formula 1, (CO2) Sis the cumulative amount (g) of carbon dioxide (CO2) generated in the test vessel containing the compost and the sample in an amount of 14.3% by weight based on the total dry weight of the sample and compost, and (CO2) B is the cumulative amount of carbon dioxide (CO2) generated in the inoculation vessel containing only compost (g), and (CO2) THV is the theoretical cumulative amount of carbon dioxide (CO2) generated in the test vessel and is expressed by the following Equation 2. [Formula 2]

number

[0014] In Equation 2, Cw is the mass of organic carbon (g) contained in the sample.

[0015] In one embodiment, the composition may further comprise a vaporization enhancer for the polylactic acid (PLA) resin.

[0016] In another embodiment, the weight ratio of the polylactic acid (PLA) resin to the vaporization promoter for the polylactic acid (PLA) resin may be 10:90 to 90:10.

[0017] In another embodiment, the composition has an improvement in vaporization facilitation (ΔVID 10W ) may be 1% or more: [Formula 3] ΔVID 10W (%)=V 10w -V THV10w

[0018] In Equation 3, V 10W is as defined above, and V THV10W is expressed by the following Equation 4. [Formula 4]

number

[0019] In Formula 4, x is the weight percent of polylactic acid (PLA) resin contained in the composition, based on the total weight of the composition.

[0020] In another embodiment, the vaporization promoter for polylactic acid (PLA) resin can satisfy at least one of the following properties: a glass transition temperature (Tg) of -45°C to 80°C, a crystallization temperature (Tc) of 60°C to 120°C, and a melting temperature (Tm) of 100°C to 170°C.

[0021] In another embodiment, a vaporization enhancer for polylactic acid (PLA) resin may include a resin including repeat units derived from 3-hydroxybutyrate (3-HB) monomers and repeat units derived from 4-hydroxybutyrate (4-HB) monomers.

[0022] In another embodiment, the vaporization promoter for polylactic acid (PLA) resin may contain repeat units derived from 4-hydroxybutyrate (4-HB) monomers in an amount ranging from 1 mol % to 80 mol % based on the total moles of repeat units derived from 3-hydroxybutyrate (3-HB) monomers and repeat units derived from 4-hydroxybutyrate (4-HB) monomers.

[0023] According to another aspect of the present disclosure, there is provided a vaporization enhancer for polylactic acid (PLA) resin, comprising a resin including repeat units derived from 3-hydroxybutyrate (3-HB) monomers and repeat units derived from 4-hydroxybutyrate (4-HB) monomers.

[0024] In one embodiment, the molar ratio of repeat units derived from 3-hydroxybutyrate (3-HB) monomers to repeat units derived from 4-hydroxybutyrate (4-HB) monomers may be from 40:60 to 99:1.

[0025] Advantageous Effects of the Invention A composition according to one embodiment of the present disclosure includes a polylactic acid (PLA) resin that has a low vaporization degree at a room temperature of 30° C., and when the cumulative amount of carbon dioxide (CO2) generated over a 10-week period is measured, the vaporization degree is high above a certain level, thereby achieving excellent biodegradation effects at room temperature.

[0026] In addition, the vaporization accelerator for polylactic acid (PLA) resin can significantly accelerate the vaporization of polylactic acid (PLA) resin, which has a low vaporization degree at room temperature of 30°C.

[0027] Therefore, the composition and vaporization promoter for polylactic acid (PLA) resin can be used in various fields to effectively protect the environment while providing excellent physical properties. [Brief description of the drawings]

[0028] [Figure 1] 1 is a graph showing the degree of vaporization (V10W) over time at room temperature of 30° C. for compositions of Examples 1 and 2 and Comparative Examples 1 and 2 of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, the present disclosure will be described in detail with reference to the embodiments. Hereinafter, the embodiments are not limited to those described below. Rather, they can be modified in various forms without changing the spirit of the present invention.

[0030] Throughout this specification, when a part is described as "comprising" elements, it is understood that other elements may be included rather than excluding other elements, unless specifically stated otherwise.

[0031] Additionally, all numbers expressing physical properties, dimensions, and the like of elements used herein are understood to be modified by the term "about" unless otherwise specified.

[0032] The present disclosure relates to a composition (a vaporizable composition or a biodegradable composition) that has a vaporization degree (V) calculated by applying the cumulative amount of carbon dioxide (CO2) generated under aerobic composting conditions. 10W ) is controlled to within a specific range, so even if the composition contains a polylactic acid (PLA) resin that is not easily biodegradable at room temperature (e.g., 25±5°C), the composition is easily biodegradable at room temperature (e.g., 25±5°C), and the vaporization promoter for the polylactic acid resin contained in the composition will be described in detail below.

[0033] [Composition] The composition according to one embodiment of the present disclosure includes a polylactic acid (PLA) resin in an amount ranging from 10% by weight to less than 100% by weight based on the total weight of the composition, and when the cumulative amount of carbon dioxide (CO2) generated over 10 weeks at 30°C is measured in accordance with ISO14855, the vaporization degree (V) represented by the following formula 1 is 0.01 to 0.15. 10w ) is 50% or more: [Formula 1]

number

[0034] In formula 1, (CO2) S is the cumulative amount (g) of carbon dioxide (CO2) generated in a test vessel containing compost and a sample (composition sample) in an amount of 14.3% by weight based on the total dry weight of the sample and compost, and (CO2) B is the cumulative amount of carbon dioxide (CO2) generated in the inoculation vessel containing only compost (g), and (CO2) THV is the theoretical cumulative amount (g) of carbon dioxide (CO2) generated in the test vessel (test vessel (a+b) containing compost (a) and sample (b) in an amount of 14.3% by weight based on the total dry weight of the sample and compost), and is expressed by the following Equation 2. [Formula 2]

number

[0035] In Equation 2, Cw is the mass (g) of organic carbon (carbon element) contained in the sample (a sample with an amount of 14.3% by weight of the total weight (x+y) of the dry weight of sample (x) and the dry weight of compost (y)). Specifically, Cw refers to the carbon element content (g) measured when elemental analysis of the sample was performed.

[0036] (CO2) S and (CO2) B The weight of the compost used to measure the moisture content may be the same. In addition, the dry weight of the compost may be calculated by loss on drying (LOD), which is a thermogravimetric principle for moisture content. That is, when the compost is dried, the difference in weight loss is measured and the dry weight is calculated by moisture analysis using a drying oven or a halogen moisture analyzer (HMA).

[0037] Degree of evaporation (V 10W ) is a value measured when a composition is broken down into low molecular weight substances and eventually completely decomposed into carbon dioxide and vaporized, rather than the degree of biodegradation (biodegradation effect) in which the composition breaks down into small pieces or molecules.

[0038] Specifically, the degree of vaporization (V 10W ) is a value obtained by measuring the cumulative amount of carbon dioxide (CO2) generated, which is the final decomposition product of the composition, in accordance with the provisions of the ISO 14855 notification (specifically, the aerobic biodegradability evaluation method of ISO 14855-1), and applying the measured cumulative amount of carbon dioxide (CO2) to Equation 1 and Equation 2, and can be an index of the biodegradability of the composition at room temperature of 30°C.

[0039] The composition according to one embodiment of the present disclosure may further include a vaporization promoter for polylactic acid (PLA) resin. Specifically, the composition further including a vaporization promoter for polylactic acid (PLA) resin has a vaporization degree (V) represented by Formula 1 of 50% or more. 10W More specifically, the vaporization degree (V 10W ) can be an indicator of the biodegradability of a composition including a polylactic acid (PLA) resin and a vaporization enhancer for a polylactic acid (PLA) resin.

[0040] That is, the degree of vaporization (V 10W ) can be a value obtained by the following procedure: as an evaluation group, a composition sample containing a polylactic acid (PLA) resin and a vaporization promoter for polylactic acid (PLA) resin at a specific content is mixed with compost and placed in a test container, and then the cumulative amount (g) of carbon dioxide (CO2) generated from the composition sample ((CO2) S ) is measured using a measuring and evaluating device (ECHO Respirometer device) under aerobic composting conditions at 30°C for 10 weeks; as a control, the cumulative amount (g) of carbon dioxide (CO2) generated in an inoculation vessel containing only compost without the composition sample ((CO2) B ) is obtained under the same conditions as the evaluation group; the cumulative amount (g) of carbon dioxide (CO2) generated in the evaluation group and the control group, respectively (CO2) S and (CO2) B The difference between the two is measured; and the theoretical cumulative amount (g) of generated carbon dioxide (CO2) is calculated as shown in Equation 2 ((CO2) THV ) to convert it to a percentage.

[0041] A composition according to one embodiment of the present disclosure includes a polylactic acid (PLA) resin and has a vaporization rate (V) above a certain level when measuring the cumulative amount of carbon dioxide (CO) generated over a 10-week period. 10W ), even if the composition contains a polylactic acid (PLA) resin with a low vaporization degree, it can produce an excellent biodegradation effect under aerobic composting conditions at a room temperature of 30° C. The pressure condition under aerobic composting conditions may be normal pressure.

[0042] Specifically, the vaporization degree (V 10W ) can be, for example, 50.1% or more, 50.2% or more, 50.4% or more, 55% or more, 60% or more, 63% or more, 65% or more, 70% or more, 72% or more, or 75% or more.

[0043] On the other hand, (CO2) in Eq. Scan be, for example, 35 g or more, 40 g or more, 45 g or more, 50 g or more, 55 g or more, or 60 g or more.

[0044] In formula 1 (CO2) S and (CO2) B The difference refers to the actual cumulative amount of carbon dioxide (CO2) generated by the sample (composition sample) itself, and can be, for example, 5 g or more, 10 g or more, 10 g to 60 g, 15 g to 50 g, or 15 g to 40 g.

[0045] (CO2) in Equation 1 THV refers to the theoretical maximum cumulative amount (g) of carbon dioxide (CO2) generated when the sample (composition sample) is completely oxidized (when 100% of the organic carbon contained in the sample is converted to carbon dioxide (CO2) in the test container containing the compost and the sample), and can be expressed by Equation 2. That is, (CO2) THV can be calculated as the product of the mass of organic carbon (carbon atoms) contained in the sample (Cw) and the ratio (44 / 12) of the molecular weight of carbon dioxide (44) to the atomic weight of carbon atom (12). (CO2) THV can be, for example, 10 g or more, 15 g or more, 20 g or more, 20 g to 60 g, 25 g to 50 g, or 30 g to 45 g.

[0046] On the other hand, the composition according to one embodiment of the present disclosure has an improvement in vaporization promotion (ΔVID 10W ) may have 1% or more: [Formula 3] ΔVID 10W (%)=V 10w -V THV10w

[0047] In Equation 3, V 10W is as defined above, and V THV10W is expressed by the following Equation 4. [Formula 4]

number

[0048] In Formula 4, x is the weight percent of polylactic acid (PLA) resin contained in the composition, based on the total weight of the composition.

[0049] In formula 4, 3.6% is the vaporization degree (V) calculated by formula 1 when a cumulative amount of carbon dioxide (CO2) is generated at 30°C for 10 weeks in accordance with ISO 14855 for a composition consisting of 100% by weight of polylactic acid (PLA) resin (a composition having only PLA resin). 10w ) and 9.5% refers to the vaporization degree (V) calculated by Formula 1 when a cumulative amount of carbon dioxide (CO2) is generated at 30°C for 10 weeks in accordance with ISO14855 for a composition consisting of 100% by weight of a vaporization promoter for polylactic acid (PLA) resin (a composition having only a vaporization promoter for polylactic acid (PLA) resin). 10w )

[0050] Improvement in evaporation promotion (ΔVID 10W ) is the actual vaporization degree of the composition (V 10W ) to the theoretical vaporization degree of the composition (V THV10W ) minus the value (V 10W -V THV10W ) and can be an indicator of the degree to which the vaporization of polylactic acid (PLA) resin is promoted by a vaporization promoter for polylactic acid (PLA) resin.

[0051] Improvement in evaporation promotion (ΔVID 10W ) can be, for example, 2% or more, 3% or more, 5% or more, 10% or more, 15% or more, 20% or more, 22% or more, 23% or more, 24% or more, 25% or more, 26% or more, 28% or more, or 30% or more.

[0052] This improvement in evaporation promotion (ΔVID 10W ) may vary greatly depending on the content or properties of the polylactic acid (PLA) resin contained in the composition, or the degree of improvement in vaporization promotion may vary greatly depending on the content, ingredients, or properties of the vaporization promoter for the polylactic acid (PLA) resin contained in the composition.

[0053] Specifically, when the content (weight ratio) of the polylactic acid (PLA) resin and the vaporization promoter for the polylactic acid (PLA) resin contained in the composition according to one embodiment of the present disclosure is 50:50, the improvement in vaporization promotion (ΔVID 10W ) can be, for example, 25% or more, 26% or more, 27% or more, or 28% or more.

[0054] In addition, when the content (weight ratio) of polylactic acid (PLA) resin and the vaporization promoter for polylactic acid (PLA) resin is 75:25, the improvement in vaporization promotion (ΔVID 10W ) can be, for example, 20% or more, 22% or more, 23% or more, or 24% or more.

[0055] On the other hand, in Equation 3, the theoretical vaporization degree of the composition (V THV10W ) can vary greatly depending on the content (weight) of polylactic acid (PLA) resin and vaporization promoter for polylactic acid (PLA) resin contained in the composition. Specifically, the vaporization degree (V THV10W ) can be, for example, 10% or more, 15% or more, 20% or more, 20% to 60%, 25% to 55%, or 25% to 50%.

[0056] More specifically, when the content (weight ratio) of the polylactic acid (PLA) resin and the vaporization promoter for the polylactic acid (PLA) resin contained in the composition according to one embodiment of the present disclosure is 50:50, the theoretical vaporization degree (V THV10W ) can be, for example, 20% or more, 30% or more, 40% or more, 20% to 60%, 30% to 55%, or 35% to 55%.

[0057] In addition, when the content (weight ratio) of the polylactic acid (PLA) resin and the vaporization promoter for the polylactic acid (PLA) resin is 75:25, the theoretical vaporization degree (V THV10W ) can be, for example, 10% or more, 15% or more, 20% or more, 20% to 60%, 20% to 50%, or 20% to 40%.

[0058] In terms of vaporization rate, when comparing a composition according to an embodiment of the present disclosure with cellulose, a representative standard biodegradable material, the composition according to an embodiment of the present disclosure has a vaporization rate (V) equal to or greater than that of cellulose. 10W ).

[0059] Specifically, a composition according to an embodiment of the present disclosure includes a polylactic acid (PLA) resin having a low vaporization degree at a room temperature of 30° C., and when the cumulative amount of carbon dioxide (CO2) generated over a period of 10 weeks is measured, the vaporization degree (V 10W ) is high above a certain level (e.g., 50% or more), resulting in excellent biodegradation effect at room temperature.

[0060] Therefore, the composition according to an embodiment of the present disclosure has excellent physical properties and can be used in various fields to effectively protect the environment.

[0061] Below, each component of a composition according to one embodiment of the present disclosure will be described in detail.

[0062] Polylactic acid (PLA) resin A composition according to an embodiment of the present disclosure may include polylactic acid (PLA) resin in an amount of 10% by weight to less than 100% by weight, based on the total weight of the composition.

[0063] Unlike petroleum-based resins, polylactic acid (PLA) resin is a biomass-based material, so it can be used as a recyclable resource and has the environmentally friendly property of being biodegraded by moisture and microorganisms when buried.

[0064] The polylactic acid (PLA) resin can be obtained from L-lactic acid, D-lactic acid, D,L-lactic acid, or a combination thereof. Specifically, the polylactic acid (PLA) resin can be a random copolymer of L-lactic acid and D-lactic acid.

[0065] The polylactic acid (PLA) resin can have a weight average molecular weight (Mw) of 10,000 to 1,000,000 g / mol, 30,000 to 500,000 g / mol, 100,000 to 300,000 g / mol, or 100,000 to 200,000 g / mol. The weight average molecular weight (Mw) can be measured by gel permeation chromatography (GPC).

[0066] The polylactic acid (PLA) resin can have a melting temperature (Tm) of 100°C to 300°C, 110°C to 280°C, 120°C to 250°C, or 120°C to 200°C.

[0067] The polylactic acid (PLA) resin can have a glass transition temperature (Tg) of 30°C to 100°C, 30°C to 80°C, 40°C to 80°C, or 45°C to 70°C.

[0068] The composition according to an embodiment of the present disclosure may contain polylactic acid (PLA) resin in an amount of 10 wt% to less than 100 wt% based on the total weight of the composition. Specifically, the composition may contain polylactic acid (PLA) resin in an amount of 10 wt% or more, 20 wt% or more, 30 wt% or more, 50 wt% or more, or 70 wt% or more and less than 100 wt%, 98 wt% or less, 95 wt% or less, 90 wt% or less, 85 wt% or less, or 80 wt% or less based on the total weight of the composition. For example, the composition may contain polylactic acid (PLA) resin in an amount of 10 wt% to less than 100 wt%, 10 wt% to 95 wt%, 30 wt% to 95 wt%, 40 wt% to 90 wt%, or 50 wt% to 80 wt% based on the total weight of the composition.

[0069] If the content of polylactic acid (PLA) resin in the composition according to one embodiment of the present disclosure is 100% by weight, the degree of vaporization at room temperature of 30° C. is very low; therefore, it may be difficult to achieve the desired biodegradation effect. Specifically, when the cumulative amount of carbon dioxide (CO2) generated at 30° C. for 10 weeks is measured according to ISO 14855 for a composition consisting of 100% by weight of polylactic acid (PLA) resin, the degree of vaporization (V) calculated by Equation 1 is 100% by weight. 10W) may be, for example, 5% or less, 4.5% or less, 4.0% or less, 3.6% or less, 3.0% or less, or 2.7% or less, thereby significantly reducing the biodegradation effect at room temperature.

[0070] Therefore, the composition according to one embodiment of the present disclosure further comprises a vaporization promoter for polylactic acid (PLA) resin, as described below, thereby accelerating the vaporization of polylactic acid (PLA) resin, which has a low vaporization degree at room temperature, and as a result, further enhancing the biodegradation effect.

[0071] Vaporization promoter for polylactic acid (PLA) resin Compositions according to embodiments of the present invention may further include a vaporization enhancer for the polylactic acid (PLA) resin.

[0072] The vaporization accelerator for polylactic acid (PLA) resin can function as an accelerator that can accelerate the vaporization of polylactic acid (PLA) resin, which has a low vaporization degree at room temperature of 30°C.

[0073] The composition according to one embodiment of the present disclosure may include a vaporization promoter for polylactic acid (PLA) resin in an amount of more than 0 wt%, 5 wt% or more, 10 wt% or more, 15 wt% or more, 20 wt% or more, 30 wt% or more, or 40 wt% or more, and less than 100 wt%, 90 wt% or less, 80 wt% or less, 70 wt% or less, 60 wt% or less, or 50 wt% or less, based on the total weight of the composition. For example, the composition may include a vaporization promoter for polylactic acid (PLA) resin in an amount of more than 0 wt% to less than 100 wt%, more than 0 wt% to 90 wt%, more than 0 wt% to 70 wt%, 5 wt% to 90 wt%, 5 wt% to 80 wt%, 10 wt% to 70 wt%, 20 wt% to 60 wt%, 25 wt% to 60 wt%, or 30 wt% to 50 wt%, based on the total weight of the composition.

[0074] When the content of the vaporization promoter for polylactic acid (PLA) resin satisfies the above-mentioned range, the vaporization of polylactic acid (PLA) resin is effectively accelerated, so that even if the composition according to one embodiment of the present disclosure contains polylactic acid (PLA) resin in an amount of 10% by weight or more, 30% by weight or more, 50% by weight or more, or 70% by weight or more, the composition can produce excellent biodegradation effect at room temperature of 30°C.

[0075] The vaporization promoter for polylactic acid (PLA) resin may contain polyhydroxyalkanoate (hereinafter referred to as "PHA") resin. PHA resin has specific physical properties (e.g., specific crystal structure, components derived from specific monomers, etc.), and therefore can effectively promote the vaporization of polylactic acid (PLA) resin.

[0076] PHA resins have physical properties similar to those of petroleum-based synthetic resins such as polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA), and are completely biodegradable and have excellent biocompatibility.

[0077] Specifically, PHA resin is a natural thermoplastic polyester polymer that accumulates in microbial cells. Since PHA resin is biodegradable, it can be composted and ultimately decomposed into carbon dioxide, water, and organic waste that does not generate toxic waste. In particular, PHA resin is biodegradable in soil and sea. Therefore, when a composition according to an embodiment of the present disclosure includes a PHA resin, the composition is biodegradable under any environmental conditions, such as soil and sea, and is environmentally adaptive. For example, when the cumulative amount of carbon dioxide (CO2) generated over 10 weeks at 30°C is measured according to ISO14855 for a composition consisting of 100% by weight of PLA resin, the vaporization degree (V) calculated by Equation 1 is 100% by weight of PLA resin. 10W ) can be, for example, 90% or more, 91% or more, 91.5% or more, or 92% or more, thereby producing a significantly excellent biodegradation effect at room temperature.

[0078] PHA resins may also be formed by the enzyme-catalyzed polymerization of one or more monomers within living cells.

[0079] Specifically, the PHA resin may be a copolymer polyhydroxyalkanoate resin (hereinafter referred to as "PHA copolymer"), more specifically, a copolymer in which repeat units derived from two or more different monomers are randomly distributed within the polymer chain. 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.

[0080] Examples of monomers that may be used in the preparation of PHA include 2-hydroxybutyrate, lactic acid, glycolic acid, 3-hydroxybutyrate (hereinafter referred to as "3-HB"), 3-hydroxypropionate (hereinafter referred to as "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-HV"). Examples of such repeat units include 3-hydroxynonanoate (hereinafter referred to as "3-HN"), 3-hydroxydecanoate (hereinafter referred to as "3-HD"), 3-hydroxydodecanoate (hereinafter referred to as "3-HDd"), 4-hydroxybutyrate (hereinafter referred to as "4-HB"), 4-hydroxyvalerate (hereinafter referred to as "4-HV"), 5-hydroxyvalerate (hereinafter referred to as "5-HV"), and 6-hydroxyhexanoate (hereinafter referred to as "6-HH"). The PHA resin may contain repeat units derived from one or more monomers selected from the above-mentioned monomers.

[0081] Specifically, the PHA resin may include repeat units (at least one repeat unit) derived from one or more monomers selected from the group consisting of 3-HB, 4-HB, 3-HP, 3-HV, 3-HH, 4-HV, 5-HV, and 6-HH.

[0082] More specifically, the PHA resin may include a repeat unit derived from a 4-HB monomer. That is, the PHA resin may be a PHA copolymer that includes a repeat unit derived from a 4-HB monomer. The PHA resin may be a PHA copolymer that includes a repeat unit derived from a 4-HB monomer and further includes a repeat unit derived from a monomer different from the 4-HB monomer, or further includes a repeat unit derived from two, three, four, five, six, or more monomers that are different from one another (two or more repeat units that are different from one another).

[0083] The vaporization accelerator for polylactic acid (PLA) resin according to one embodiment of the present disclosure includes a resin (PHA copolymer) containing a repeat unit derived from a 4-HB monomer, and may also contain a repeat unit (at least one repeat unit) derived from at least one monomer selected from the group consisting of a 3-HB monomer, a 3-HP monomer, a 3-HV monomer, a 3-HH monomer, a 4-HV monomer, a 5-HV monomer, and a 6-HH monomer. More specifically, the vaporization accelerator for polylactic acid (PLA) resin may include a resin (PHA copolymer) containing a repeat unit derived from a 3-HB monomer (hereinafter referred to as a "3-HB repeat unit") and a repeat unit derived from a 4-HB monomer (hereinafter referred to as a "4-HB repeat unit"). For example, the accelerator may include a poly-3-hydroxybutyrate-co-4-hydroxybutyrate (hereinafter referred to as a "P3-HB-co-4-HB") copolymer.

[0084] According to one embodiment of the present disclosure, controlling the content of 3-HB and 4-HB repeat units in the polylactic acid (PLA) resin can be important to facilitate vaporization of the PHA resin while increasing the biodegradability of the composition in soil and ocean.

[0085] For example, in a PHA resin containing 3-HB repeat units and 4-HB repeat units, the molar ratio of 3-HB repeat units to 4-HB repeat units may be 20:80 to 99:1, 30:70 to 99:1, 40:60 to 99:1, 50:50 to 95:5, 50:50 to 94:6, 50:50 to 92:8, 55:45 to 92:8, or 55:45 to 90:10. When the molar ratio of 3-HB repeat units to 4-HB repeat units satisfies the above range, it may be more advantageous to achieve the biodegradation effect desired in the present disclosure.

[0086] Specifically, the content of 4-HB repeat units may be 1 mol % to 80 mol %, 2 mol % to 70 mol %, 3 mol % to 60 mol %, 5 mol % to 50 mol %, 8 mol % to 45 mol %, or 10 mol % to 45 mol % based on the total moles (number of moles) of 3-HB repeat units and 4-HB repeat units.

[0087] Additionally, in PHA resins that contain at least one 4-HB repeat unit, the crystallinity of the PHA resin may be adjusted depending on the content of the 4-HB repeat unit. That is, the PHA resin may be a PHA copolymer with controlled crystallinity. Specifically, PHA resins can be classified as semi-crystalline PHA (scPHA) copolymers or amorphous PHA (aPHA) copolymers depending on the content of the 4-HB repeat unit.

[0088] The crystallinity-adjusted PHA resin may have its crystallinity and amorphousness adjusted as the degree of disorder in the molecular structure increases. Specifically, the crystallinity and amorphousness can be determined by the type of monomer, the ratio of repeating units derived from the monomer, or the type and / or content of isomers.

[0089] Specifically, the PHA resin may be an amorphous PHA (aPHA) copolymer containing 4-HB repeat units. Since the vaporization promoter for polylactic acid (PLA) resin contains such an amorphous PHA (aPHA) copolymer, the vaporization of polylactic acid (PLA) resin can be more effectively promoted.

[0090] On the other hand, the PHA resin can have 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°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.

[0091] The crystallization temperature (Tc) of the PHA resin may not be measured, or may be, for example, 60°C to 120°C, 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.

[0092] The melting temperature (Tm) of the PHA resin may not be measured, for example, or may be, for example, 100°C to 170°C, 105°C to 160°C, 110°C to 150°C, 115°C to 155°C, or 120°C to 140°C.

[0093] The PHA resin may have a weight average molecular weight (Mw) of, for example, 10,000 g / mol to 1,200,000 g / mol. Specifically, the weight average molecular weight of the PHA resin may be 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, or 200,000 g / mol to 1,200,000 g / mol. 00,000 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, 2 00,000g / mol~800,000g / mol, 200,000g / mol~700,000g / mol, 250,000g / mol~650,000g / mol, 200,000g / mol~400,000g / mol, 300,000g / mol~800,000g / mol, 300,000g / mol~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.

[0094] On the other hand, the composition according to one embodiment of the present disclosure may contain a polylactic acid (PLA) resin and a vaporization promoter for polylactic acid (PLA) resin at a specific content ratio. Specifically, the content ratio (weight ratio) of the polylactic acid (PLA) resin and the vaporization promoter for polylactic acid (PLA) resin may be, for example, 10:90 to 90:10, 15:85 to 90:10, 20:80 to 90:10, 25:75 to 90:10, 30:70 to 90:10, 40:60 to 90:10, 45:55 to 85:15, 50:50 to 85:15, 50:50 to 80:20, 50:50 to 75:25, or 50:50 to 70:30. When the content (weight ratio) of the polylactic acid (PLA) resin and the vaporization promoter for the polylactic acid (PLA) resin satisfies the above-mentioned range, the vaporization of the polylactic acid (PLA) resin can be significantly accelerated.

[0095] Additives The composition according to one embodiment of the present disclosure may further comprise at least one additive selected from the group consisting of antioxidants, compatibilizers, bulking agents, nucleating agents, melt strength enhancing agents, and slip agents.

[0096] The content of the additives may be adjusted according to the desired effect and use of the composition. The content of the additives 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, and 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, based on the total weight of the composition.

[0097] The additives may be commonly known additives depending on the desired effect and application.

[0098] Modes of the Invention Hereinafter, the present disclosure will be described in detail with reference to the following examples. However, the following examples are for the purpose of illustrating the present disclosure, and the scope of the embodiments of the present disclosure is not limited thereto. EXAMPLES

[0099] Example 1 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (NatureWorks, 4032D) and polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, aPHA) (CJ Cheil Jedang, Korea) as a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 50:50.

[0100] Example 2 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (NatureWorks, 4032D) and polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, aPHA) (CJ Cheil Jedang, Korea) as a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 75:25.

[0101] Example 3 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (Nature Works, 2003D) and polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, aPHA) (CJ Cheil Jedang, Korea) as a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 50:50.

[0102] Example 4 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (Nature Works, 2003D) and polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, aPHA) (CJ Cheil Jedang, Korea) as a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 70:30.

[0103] Example 5 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (Nature Works, 2003D) and polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, aPHA) (CJ Cheil Jedang, Korea) used as a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 60:40.

[0104] Comparative Example 1 Compositions were prepared consisting of 100% by weight polylactic acid (PLA) resin (NatureWorks, 4032D), as shown in Table 1 below.

[0105] Comparative Example 2 A composition consisting of 100 wt % polyhydroxyalkanoate (PHA) resin (P3-HB-co-4-HB, scPHA) (CJ Cheil Jedang, Korea) was prepared as a vaporization promoter for polylactic acid (PLA) resin, as shown in Table 1 below.

[0106] Comparative Example 3 As shown in Table 1 below, a composition was prepared by mixing polylactic acid (PLA) resin (NatureWorks, 4032D) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) (Tianan, China) as a vaporization enhancer for polylactic acid (PLA) resin in a weight ratio of 50:50.

[0107] Control Example 1 Cellulose, a standard biodegradable material, was used.

[0108] The contents and physical properties of the compositions obtained in the Examples and Comparative Examples are summarized in Table 1 below. Here, in Table 1 below, the Tg and Tm of Comparative Example 1 are the values ​​of Tg and Tm measured for the PLA resin used in Comparative Example 1.

[0109] [Table 1]

[0110] Evaluation example Evaluation example 1: Degree of vaporization The cumulative amount of carbon dioxide generated was measured under aerobic composting conditions in accordance with ISO 14855, and the degree of evaporation (V 10W ) was calculated.

[0111] Specifically, as an evaluation group, 14.3% by weight of each composition sample of the examples and comparative examples was taken based on the total dry weight of the composition sample and compost, and mixed with compost (Abnexo Co., Ltd.) to prepare a test vessel containing the mixture. In such a case, the initial moisture content of the compost was measured by LOD moisture measurement using an HMA or a drying oven. The dry weight was adjusted by adding additional moisture to adjust the final moisture content to 50%. In addition, in accordance with the notification regulations of ISO14855, a mixture was prepared by uniformly mixing 20 g of a dry composition sample (moisture content 0%) with 240 g of compost with a moisture content of 50% (dry weight 120 g) to adjust the ratio of the sample to the compost to 1:6.

[0112] In addition, as a control, an inoculation vessel containing only compost without any composition sample was prepared.

[0113] After that, after 10 weeks at normal pressure and aerobic conditions at 30°C, the carbon dioxide generated in each container was collected using an ECHO Respirometer device and titrated with an NIR (near-infrared sensor) via a system inside the device to measure the cumulative amount of carbon dioxide generated from each container.

[0114] Using the measured cumulative amount of generated carbon dioxide, the degree of vaporization (V 10W ) was calculated: [Formula 1]

number

[0115] In formula 1, (CO2) S is the cumulative amount (g) of carbon dioxide (CO2) evolved in the test vessel containing compost and sample in an amount of 14.3% by weight based on the total dry weight of the sample and compost, and (CO2) B is the cumulative amount of carbon dioxide (CO2) generated in the inoculation vessel containing only compost (g), and (CO2) THVis the theoretical cumulative amount of carbon dioxide (CO2) generated in the test vessel and is expressed by the following Equation 2. [Formula 2]

number

[0116] In Equation 2, Cw is the mass (g) of organic carbon contained in the sample. Specifically, Cw is the content (g) of carbon atoms contained in the sample.

[0117] Evaluation example 2: Improvement in evaporation promotion In order to measure the degree to which the vaporization of polylactic acid (PLA) resin is promoted by the vaporization promoter for polylactic acid (PLA), the degree of improvement in vaporization promotion (ΔVID 10W ) was evaluated.

[0118] Specifically, the degree of vaporization (V 10W ) and theoretical vaporization degree (V THV10W ) to calculate the improvement in vaporization promotion (ΔVID 10W The theoretical degree of vaporization (V THV10W ) was calculated: [Formula 4]

number

[0119] In Formula 4, x is the weight percent of polylactic acid (PLA) resin contained in the composition, based on the total weight of the composition.

[0120] The results obtained in Evaluation Examples 1 and 2 are summarized in Tables 2 and 3 below and in FIG.

[0121] [Table 2]

[0122] [Table 3]

[0123] As can be seen from Table 3 and FIG. 1, when the cumulative amount of carbon dioxide (CO2) generated over 10 weeks at 30° C. was measured, the vaporization degree (V) of the compositions of Examples 1 to 5 actually evaluated was 10w ) are all 50% or more, which indicates that all of them realize the degree of vaporization of cellulose, a representative standard biodegradable material. Specifically, the compositions of Examples 1 to 5 are 50% or more higher than the vaporization degree (V) of Comparative Example 1, which used a composition consisting of 100% by weight of polylactic acid (PLA) resin. 10W Significantly improved vaporization rate (V) 3.6% 10W )

[0124] In particular, in Examples 1 to 5 in which a polylactic acid (PLA) resin and a composition containing a vaporization promoter for polylactic acid (PLA) resin were used, the degree of improvement in vaporization promotion (ΔVID 10W ) is the vaporization degree (V) of Comparative Example 1, which uses a composition made of 100% by weight of polylactic acid (PLA) resin. 10W ), this has improved significantly to more than 5%, specifically to more than 20%.

[0125] In particular, in the composition of Example 1, which employs a polylactic acid (PLA) resin and a vaporization promoter for polylactic acid (PLA) resin in a weight ratio of 50:50, the theoretical cumulative amount of carbon dioxide (CO2) generated ((CO2) THV If the polylactic acid (PLA) resin is completely oxidized (100% conversion), the total amount of carbon dioxide (CO2) generated from the polylactic acid (PLA) resin is 38.8 g. If we assume that the polylactic acid (PLA) resin does not vaporize at room temperature, the cumulative amount of carbon dioxide (CO2) generated from the polylactic acid (PLA) resin is the above (CO2) THV However, after 10 weeks, the actual amount of carbon dioxide (CO2) produced ((CO2) S -(CO2) B ) was 29.7g, which indicates that the vaporization of polylactic acid (PLA) resin was promoted by the vaporization promoter for polylactic acid (PLA) resin, that is, it had a vaporization promotion effect. In other words, the amount of carbon dioxide (CO2) actually generated ((CO2) S -(CO2)B ) and (CO2) THV The excess amount of about 10 g, which is the difference from half of the predicted value, is predicted to be the amount of carbon dioxide (CO2) generated from polylactic acid (PLA) resin whose vaporization was promoted by the vaporization promoter for polylactic acid (PLA) resin.

[0126] It is confirmed from the above results that the vaporization promoter for polylactic acid (PLA) resin not only has a high vaporization degree but also can significantly accelerate the vaporization of polylactic acid (PLA) resin.

[0127] On the other hand, in the composition of Comparative Example 3 in which PHBV as a vaporization promoter for polylactic acid (PLA) resin was mixed with polylactic acid (PLA) resin in a weight ratio of 50:50, no vaporization promotion effect was observed. Therefore, it was confirmed that the PHA resin of the present disclosure having specific physical properties can specifically promote the vaporization of polylactic acid (PLA) resin.

Claims

1. A composition comprising a polylactic acid (PLA) resin in an amount ranging from 10% by weight to less than 100% by weight based on the total weight of the composition, and a carbon dioxide (CO ２ When the cumulative amount of vaporization is measured according to ISO 14855, the vaporization degree (V １０ｗ ) is 50% or more: [Formula 1] [0010] [In formula 1, (CO ２ ) Ｓ is the carbon dioxide (CO) generated in a test vessel containing compost and the sample in an amount of 14.3% by weight based on the total dry weight of the sample and the compost. ２ ) is the cumulative amount (g) of (CO ２ ) Ｂ is the carbon dioxide (CO) generated in an inoculation vessel containing only compost. ２ ) (g) (CO ２ ) ＴＨＶ is the carbon dioxide (CO ２ ) is a theoretical cumulative amount of [Formula 2] [0025] [In Equation 2, Cw is the mass of organic carbon (g) contained in the sample].

2. 10. The composition of claim 1, further comprising a vaporization enhancer for the polylactic acid (PLA) resin.

3. 3. The composition of claim 2, wherein the weight ratio of the polylactic acid (PLA) resin to the vaporization enhancer for the polylactic acid (PLA) resin is from 10:90 to 90:

10.

4. The improvement in vaporization promotion (ΔVID １０Ｗ 3. The composition of claim 2, wherein the content of: [Formula 3] ΔVID １０Ｗ (%)=V １０ｗ -V ＴＨＶ１０ｗ [In formula 3, V １０Ｗ is as defined in claim 1; V ＴＨＶ１０Ｗ is represented by the following formula 4. [Formula 4] [0030] [In Equation 4, x is the weight percent of the polylactic acid (PLA) resin present in the composition based on the total weight of the composition].

5. 3. The composition of claim 2, wherein the vaporization enhancer for polylactic acid (PLA) resin satisfies at least one of the following characteristics: Glass transition temperature (Tg) -45°C to 80°C, Crystallization temperature (Tc) 60°C to 120°C, and Melting temperature (Tm) 100°C to 170°C.

6. 3. The composition of claim 2, wherein the vaporization enhancer for polylactic acid (PLA) resin comprises a resin containing repeat units derived from 4-hydroxybutyrate (4-HB) monomer and at least one monomer selected from the group consisting of 3-hydroxybutyrate (3-HB), 3-hydroxypropionate (3-HP), 3-hydroxyvalerate (3-HV), 3-hydroxyhexanoate (3-HH), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV), and 6-hydroxyhexanoate (6-HH).

7. 7. The composition of claim 6, wherein the vaporization enhancer for the polylactic acid (PLA) resin comprises a resin containing repeat units derived from the 3-hydroxybutyrate (3-HB) monomer and repeat units derived from the 4-hydroxybutyrate (4-HB) monomer.

8. 8. The composition of claim 7, wherein the vaporization enhancer for polylactic acid (PLA) resin comprises repeat units derived from the 4-hydroxybutyrate (4-HB) monomer in an amount ranging from 1 mol % to 80 mol %, based on the total moles of repeat units derived from the 3-hydroxybutyrate (3-HB) monomer and the 4-hydroxybutyrate (4-HB) monomer.

9. A vaporization promoter for polylactic acid (PLA) resin, the vaporization promoter for polylactic acid (PLA) resin comprising a resin containing a repeating unit derived from a 3-hydroxybutyrate (3-HB) monomer and a repeating unit derived from a 4-hydroxybutyrate (4-HB) monomer.

10. The vaporization promoter for polylactic acid (PLA) resin according to claim 9, wherein the molar ratio of repeating units derived from the 3-hydroxybutyrate (3-HB) monomer to repeating units derived from the 4-hydroxybutyrate (4-HB) monomer is from 40:60 to 99:1.

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