Composition for biodegradable meltblown nonwoven fabric and biodegradable meltblown nonwoven fabric produced using the same

Abstract

The present invention relates to a composition for biodegradable meltblown nonwoven fabrics and biodegradable meltblown nonwoven fabrics produced using the same. Specifically, according to one embodiment of the present invention, the composition for biodegradable meltblown nonwoven fabrics contains a polyhydroxyalkanoate (Pha) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of at least 30 g / 10 min measured at 210°C and 2.16 kg according to ASTM D1238. This makes the composition environmentally friendly, biodegradable, and biocompatible, and it can improve the uniformity of fiber diameter produced under high-temperature and high-pressure conditions, such as the meltblown method, as well as performance such as filtration, moisture permeability, and flexibility.

Description

[Technical Field]

[0001] The present invention relates to a composition for a biodegradable meltblown nonwoven fabric and a meltblown nonwoven fabric prepared using the same. [Background technology]

[0002] In recent years, amid growing concern about environmental issues, active research has been conducted into the treatment and recycling of various household wastes. Specifically, polymeric materials, which are inexpensive and easy to process, are widely used in the manufacture of various products such as paper, film, textiles, packaging materials, bottles, and containers. However, when these products reach the end of their lifespan, incineration can release harmful substances, and natural decomposition can take hundreds of years, depending on the type.

[0003] Therefore, research is ongoing into biodegradable polymers that can decompose in a short period of time, making them environmentally friendly, while also improving mechanical properties such as flexibility and strength, productivity, and processability, thereby extending the life of the product itself, reducing waste, and increasing recyclability.

[0004] Polyhydroxyalkanoates (PHAs) are biodegradable polymers composed of several hydroxylcarboxylic acids that are produced by many microorganisms and used as intracellular storage materials. Polyhydroxyalkanoates have similar physical properties to conventional petroleum-derived synthetic polymers such as polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA), and are completely biodegradable and highly biocompatible.

[0005] Nonwoven fabrics are industrial textile materials used in a variety of fields, for example, as a component material in filtration processes to control suspended particles such as airborne particles and gases, or to control the purity of water used in industrial sites such as food processing. In particular, since the 2000s, there has been growing concern about the harmful effects of yellow sand, fine dust, and ultrafine dust on the human body, and the novel coronavirus outbreak of 2019 has led to increased interest in nonwoven fabrics used as filtration materials, leading to active research into these materials.

[0006] Conventionally, petrochemical polymer materials have been used as materials for nonwoven fabrics. However, because petrochemical polymer materials are difficult to recover and recycle after use, they are left in the soil and ocean, causing serious environmental pollution. Biodegradable polymers that can improve biodegradability have been used, but the raw materials are expensive, and there are limitations to improving the filtration, air permeability, flexibility, and other properties required for nonwoven fabrics.

[0007] Furthermore, nonwoven fabrics are mainly produced by the meltblowing method or the spunbonding method. Meltblown nonwoven fabrics can be produced using ultrafine fibers compared to spunbonded nonwoven fabrics, and therefore have excellent flexibility and are easy to laminate with other nonwoven fabrics. However, because polymers are melt-spun under high temperature and pressure, the diameter of the produced fibers is not uniform. Therefore, there is a demand for the development of biodegradable nonwoven fabrics that are environmentally friendly due to their excellent biodegradability and biocompatibility in addition to properties such as filtering ability, breathability, and flexibility, and that have excellent fiber diameter uniformity produced under high temperature and high pressure conditions such as the meltblown method. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Korean Patent Publication No. 2012-0103158 Summary of the Invention [Problem to be solved by the invention]

[0009] Therefore, an object of the present invention is to provide an environmentally friendly biodegradable nonwoven fabric that has excellent properties such as filtering ability, air permeability, and flexibility, as well as excellent biodegradability and biocompatibility, and has excellent uniformity in the fiber diameter produced under high-temperature and high-pressure conditions such as by the melt-blown method. [Means for solving the problem]

[0010] A composition for biodegradable meltblown nonwoven fabrics according to one embodiment of the present invention comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of 30 g / 10 min or greater, measured at 210°C and 2.16 kg in accordance with ASTM D1238.

[0011] According to one embodiment of the present invention, the PHA resin may contain 0.1% to 60% by weight of 4-hydroxybutyric acid (4-HB) repeat units.

[0012] According to one embodiment of the present invention, the PHA resin may comprise a first PHA resin.

[0013] According to one embodiment of the present invention, the first PHA resin may contain 15% to 60% by weight of 4-hydroxybutyric acid (4-HB) repeating units and have a melt flow index (MFI) of 0.1 g / 10 min to 20 g / 10 min when measured at 165°C and 5 kg in accordance with ASTM D1238.

[0014] According to one embodiment of the present invention, the PHA resin may include a second PHA resin.

[0015] According to one embodiment of the present invention, the second PHA resin may contain 0.1% to 30% by weight of 4-hydroxybutyric acid (4-HB) repeating units and have a melt flow index of 0.1 g / 10 min to 15 g / 10 min when measured at 165°C and 5 kg in accordance with ASTM D1238.

[0016] According to one embodiment of the present invention, the composition for a biodegradable meltblown nonwoven fabric may contain at least one biodegradable resin selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate (PBST), polyhydroxybutyrate valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), and thermoplastic starch (TPS).

[0017] According to one embodiment of the present invention, the weight ratio of the PHA resin to the biodegradable resin may be 1:99 to 99:1.

[0018] According to one embodiment of the present invention, the weight ratio of the PHA resin to the polylactic acid resin may be 20:80 to 70:30.

[0019] According to one embodiment of the present invention, the composition for biodegradable meltblown nonwoven fabrics may further comprise at least one additive selected from the group consisting of pigments, dye absorbers, light absorbers, antioxidants, compatibilizers, bulking agents, nucleating agents, melt strength agents, slip agents, and fluidizing agents.

[0020] According to one embodiment of the present invention, the PHA resin may further comprise at least one repeat unit selected from the group consisting of 3-hydroxybutyric acid (3-HB), 3-hydroxypropionic acid (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV), and 6-hydroxyhexanoate (6-HH).

[0021] According to one embodiment of the present invention, the composition for biodegradable meltblown nonwoven fabrics has a melt flow index of 10 g / 10 min to 30 g / 10 min when measured at 190°C and 2.16 kg according to ASTM D1238, and a weight average molecular weight of 500,000 g / mol or less.

[0022] Another embodiment of the present invention provides a biodegradable meltblown nonwoven fabric comprising biodegradable fibers, the biodegradable fibers comprising a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and the biodegradable fibers have an average diameter of 10 μm or less and a standard deviation of the average diameter of 1.3 or less.

[0023] The biodegradable meltblown nonwoven fabric according to another embodiment of the present invention may have a filtration efficiency of 8% or more at 0.3 μm and 10% or more at 0.5 μm, in accordance with KS K ISO 9073-152007, a total thickness of 0.05 mm to 20 mm, and a basis weight of 10 gsm to 500 gsm.

[0024] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may have a warp strength of 3N or more and a warp elongation of 6% or more for a basis weight of 30 gsm in accordance with K ISO 9073-3:1989.

[0025] According to another embodiment of the present invention, the biodegradable fiber may be a bicomponent fiber with a different cross section, or a bicomponent fiber with two or more components, or three or more components.

[0026] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further have a functional coating layer on at least one surface.

[0027] A method for producing a biodegradable meltblown nonwoven fabric according to another embodiment of the present invention includes melt-extruding a composition for a biodegradable meltblown nonwoven fabric or pellets produced therefrom, followed by spinning, wherein the composition for the biodegradable meltblown nonwoven fabric comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units and has a melt flow index (MFI) of 30 g / 10 min or more, as measured at 210°C and 2.16 kg in accordance with ASTM D1238.

[0028] According to another embodiment of the present invention, the melt extrusion temperature may be 150 to 230°C.

[0029] According to another embodiment of the present invention, the spinning step may be carried out so that the basis weight of the biodegradable meltblown nonwoven fabric to be produced is adjusted to 10 gsm to 500 gsm.

[0030] According to another embodiment of the present invention, the step of spinning the composition for biodegradable meltblown nonwoven fabric may be carried out using a sheath-core composite spinning device.

[0031] According to another embodiment of the present invention, the weight ratio of the raw materials supplied to the core and the sheath may be 5:95 to 95:5.

[0032] According to another embodiment of the present invention, the core may be provided with the composition for a biodegradable meltblown nonwoven fabric. [Effects of the Invention]

[0033] A composition for biodegradable meltblown nonwoven fabrics according to one embodiment of the present invention contains a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of 30 g / 10 min or greater at 210°C and 2.16 kg as measured in accordance with ASTM D1238. Therefore, in addition to excellent properties such as degradability and biocompatibility, the composition also has properties such as filterability, breathability, and flexibility, and can improve the uniformity of the diameter of fibers produced under high-temperature, high-pressure conditions such as the meltblown method, and is environmentally friendly.

[0034] Furthermore, biodegradable meltblown nonwoven fabrics can be produced directly from the composition for biodegradable meltblown nonwoven fabrics, or biodegradable meltblown nonwoven fabrics can be produced using biodegradable pellets obtained from the composition for biodegradable meltblown nonwoven fabrics, which is convenient in that the process can be selected as needed.

[0035] Furthermore, the composition for biodegradable meltblown nonwoven fabrics and the biodegradable meltblown nonwoven fabrics obtained using the same have excellent thermal and mechanical properties, and are biodegradable in both soil and the ocean, so they can be advantageously applied to a wider variety of fields and can exhibit excellent properties. [Brief explanation of the drawings]

[0036] [Figure 1] 1 is a scanning electron microscope (SEM, 100x magnification) image of the biodegradable meltblown nonwoven fabric of Example 14. [Figure 2] 1 is a scanning electron microscope (SEM, 1,000x magnification) image of the biodegradable meltblown nonwoven fabric of Example 14. DETAILED DESCRIPTION OF THE INVENTION

[0037] The present invention will be described in detail below. The present invention is not limited to the disclosure given below, and the invention may be embodied in various forms without departing from the gist of the present invention.

[0038] In this specification, when a part is described as "comprising" an element, it does not mean that the part excludes other elements, but that the part may include other elements, unless otherwise specified.

[0039] Unless otherwise specified, the numerical values ​​and expressions relating to the amounts of components, reaction conditions, etc. used herein can be understood even if modified by the word "approximately."

[0040] In this specification, terms such as "first," "second," etc. are used in describing various components. However, these components should not be bound by these terms. These terms are used simply to distinguish one component from another.

[0041] Biodegradable meltblown nonwoven fabric composition A composition for biodegradable meltblown nonwoven fabrics according to one embodiment of the present invention comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of 30 g / 10 min or greater, measured at 210°C and 2.16 kg in accordance with ASTM D1238.

[0042] Nonwoven fabrics are made by bonding fiber aggregates or films by physical or chemical means, rather than by spinning, weaving, or knitting. They are produced directly from fibers, either by the fusion strength of the fibers themselves or by entanglement of the fibers. Traditionally, nonwoven fabrics have been produced using petrochemical materials such as polypropylene (PP), but their biodegradability is low. For this reason, a method using polylactic acid (PLA) as a nonwoven fabric material has been proposed. However, the degree of improvement in biodegradability is not significant. Due to its low flexibility and rough and stiff texture, PLA has poor usability and wearing comfort, making it difficult to apply to various fields.

[0043] Nonwoven fabrics are mainly produced by the meltblowing method or the spunbonding method. Meltblown nonwoven fabrics can be produced using ultrafine fibers compared to spunbonded nonwoven fabrics, and therefore have superior flexibility and can be easily laminated with other nonwoven fabrics. However, because polymers are melt-spun under high temperature and pressure, the diameter of the produced fibers is not uniform.

[0044] However, the composition for biodegradable meltblown nonwoven fabrics according to an embodiment of the present invention is a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of 30 g / 10 min or more at 210°C and 2.16 kg as measured in accordance with ASTM D1238. As a result, in addition to excellent properties such as degradability and biocompatibility, the composition has properties such as filterability, air permeability, and flexibility, and can improve the uniformity of the diameter of fibers produced under high-temperature and high-pressure conditions such as the meltblown method, and is environmentally friendly.

[0045] A composition for a biodegradable meltblown nonwoven fabric according to an embodiment of the present invention comprises a polyhydroxyalkanoate resin containing 4-hydroxybutyric acid (4-HB) repeat units.

[0046] Specifically, the composition for biodegradable meltblown nonwoven fabrics according to an embodiment of the present invention contains a polyhydroxyalkanoate (PHA) resin, which is a copolymerized polyhydroxyalkanoate resin containing 4-hydroxybutyric acid (4-HB) repeating units, specifically a specific first PHA resin and / or a specific second PHA resin containing 4-HB repeating units. This composition has excellent biodegradability and biocompatibility, making it easy to produce environmentally friendly biodegradable meltblown nonwoven fabrics with excellent properties.

[0047] Furthermore, the composition for biodegradable meltblown nonwoven fabrics and the biodegradable meltblown nonwoven fabrics obtained using the same have excellent thermal and mechanical properties, and are biodegradable in both soil and the ocean, so they can be advantageously applied to a wider variety of fields and can exhibit excellent properties.

[0048] PHA is a natural thermoplastic polyester polymer that accumulates within microbial cells. Because it is a biodegradable material, it can be composted and ultimately decomposes into carbon dioxide, water, and organic waste without producing hazardous waste. In particular, PHA is biodegradable in soil and the ocean, and therefore, biodegradable meltblown nonwoven fabric compositions and biodegradable meltblown nonwoven fabrics made therefrom may possess environmentally friendly characteristics due to the inclusion of PHA resins. Therefore, the biodegradable meltblown nonwoven fabric compositions and biodegradable meltblown nonwoven fabrics made therefrom have the significant advantage of being biodegradable and environmentally friendly, making them applicable in a variety of fields.

[0049] Specifically, PHA is a natural thermoplastic polyester polymer that accumulates within microbial cells. When a bacterium is supplied with nutrients (nitrogen sources, phosphorus, etc.) unevenly, it accumulates PHA within the cell and stores carbon and energy.

[0050] Furthermore, PHA has similar physical properties to conventional petroleum-derived synthetic polymers such as polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA), and is completely biodegradable and has excellent biocompatibility.

[0051] In particular, unlike other environmentally friendly plastic materials such as PBS, PLA, and PTT, PHA can be synthesized from over 150 types of monomers, and depending on the type of monomer, hundreds of different types of PHA can be prepared. Depending on the type of monomer, there are hundreds of different types of PHA, each with completely different structures and properties.

[0052] PHA resins may be composed of a single monomer repeat unit within living cells, or may be formed by polymerizing one or more types of monomer repeat units. Specifically, PHA resins may be homopolyhydroxyalkanoate resins (hereinafter referred to as HOMO PHA resins) or copolymerized polyhydroxyalkanoate resins (hereinafter referred to as copolymerized PHA resins), i.e., copolymers in which different repeat units are randomly distributed in the polymer chain.

[0053] Examples of repeating units that the PHA resin may have include 2-hydroxybutyrate, lactic acid, glycolic acid, 3-hydroxybutyric acid (hereinafter referred to as 3-HB), 3-hydroxypropionic acid (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-HO), 3-hydroxynonanoate (hereinafter referred to as 3-HN), 3-hydroxydecanoate (hereinafter referred to as 3-HD), 3-hydroxydodecanoate (hereinafter referred to as 3-HDd), 4-hydroxybutyric acid (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 one or more repeating units selected from the above.

[0054] Specifically, the PHA resin may contain one or more repeating units selected from the group consisting of 3-HB, 4-HB, 3-HP, 3-HH, 3-HV, 4-HV, 5-HV, and 6-HH.

[0055] That is, the PHA resin may be a HOMO type PHA resin composed only of 4-HB repeating units, or a copolymer type PHA resin containing 4-HB repeating units.

[0056] The PHA resin may be a copolymer PHA resin containing 4-HB repeating units and one other repeating unit different from the 4-HB repeating units, or may be a copolymer PHA resin containing two, three, four, five, six or more different repeating units. For example, the PHA resin may be poly-3-hydroxybutyrate-co-4-hydroxybutyrate (hereinafter referred to as 3HB-co-4HB).

[0057] Furthermore, the PHA resin may contain isomers. For example, the PHA resin may contain structural isomers, enantiomers, or geometric isomers. Specifically, the PHA resin may contain structural isomers.

[0058] The PHA resin may also be a copolymer PHA resin with controlled crystallinity. For example, the PHA resin may contain at least one type of 4-HB repeating unit, and the crystallinity of the PHA resin may be adjusted by controlling the content of the 4-HB repeating unit.

[0059] For example, the PHA resin may be a copolymer PHA resin containing at least one repeating unit selected from the group consisting of 3-hydroxybutyric acid (3-HB), 4-hydroxybutyric acid (4-HB), 3-hydroxypropionic acid (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV), and 6-hydroxyhexanoate (6-HH).

[0060] Specifically, the copolymer PHA resin contains 4-HB repeating units and may further contain one or more repeating units selected from the group consisting of 3-HB repeating units, 3-HP repeating units, 3-HH repeating units, 3-HV repeating units, 4-HV repeating units, 5-HV repeating units, and 6-HH repeating units. More specifically, the PHA resin may have 4-HB repeating units and 3-HB repeating units.

[0061] More specifically, the PHA resin may contain 0.1 to 60% by weight of 4-HB repeating units. For example, the PHA resin may be a copolymer PHA resin containing 4-HB repeating units and 3-HB repeating units, and may contain 0.1 to 60% by weight of 4-HB repeating units.

[0062] The PHA resin may contain 4-HB repeat units in an amount of 0.5% to 50% by weight, 1% to 45% by weight, 5% to 45% by weight, 8% to 40% by weight, 10% to 38% by weight, 15% to 35% by weight, or 20% to 30% by weight.

[0063] The PHA resin may also be a copolymer PHA resin containing 4-HB repeating units and 3-HB repeating units, and may contain 20% or more by weight of 3-HB repeating units. For example, the PHA resin may contain 3-HB repeating units in an amount of 35% or more, 40% or more, 50% or more, 60% or more, 70% or more, or 75% or more to 99% or less, 98% or less, 97% or less, 96% or less, 95% or less, 93% or less, 91% or less, 90% or less, 80% or less, 70% or less, 60% or less, or 55% or less.

[0064] The crystallinity-adjusted PHA resin may be one in which the degree of crystallinity and amorphousness are adjusted as the degree of disorder in the molecular structure increases, specifically by adjusting the type or proportion of monomers or the type or content of isomers.

[0065] According to one embodiment of the present invention, the PHA resin may contain two or more PHA resins with different crystallinity. Specifically, two or more PHA resins with different crystallinity may be mixed together to prepare a resin having a 4-HB repeat unit content within the above-mentioned specific range.

[0066] Specifically, the PHA resin may contain a first PHA, which is an amorphous PHA resin with controlled crystallinity.

[0067] The first PHA resin is an amorphous PHA resin with controlled crystallinity (hereinafter referred to as aPHA resin) and can contain 4-HB repeat units in an amount of 15% to 60% by weight, 15% to 55% by weight, 20% to 55% by weight, 25% to 55% by weight, 30% to 55% by weight, 35% to 55% by weight, 20% to 50% by weight, 25% to 50% by weight, 30% to 50% by weight, 35% to 50% by weight, or 20% to 40% by weight.

[0068] The glass transition temperature (Tg) of the first PHA resin may be −45° C. to −10° C., −35° C. to −15° C., −35° C. to −20° C., or −30° C. to −20° C. The crystallization temperature (Tc) of the first PHA resin may not be measured, or may be 60° C. to 120° C., 60° C. to 110° C., 70° C. to 120° C., or 75° C. to 115° C. The melting temperature (Tm) of the first PHA resin may be unmeasurable, or may be 100° C. to 170° C., 100° C. to 160° C., 110° C. to 160° C., or 120° C. to 150° C.

[0069] In this specification, the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm) can be measured using a differential scanning calorimeter (DSC). Specifically, Tg (glass transition temperature), Tc (crystallization temperature), and Tm (melting temperature) can be measured by performing the first or second scan in the differential scanning calorimetry (DSC) mode, and can be confirmed from the heat flow curve obtained by these scans. More specifically, the glass transition temperature (Tg), crystallization temperature (Tc), and melting temperature (Tm) can be confirmed from the heat flow curve obtained when the temperature is increased from 40°C to 180°C at 10°C / min and then cooled to -50°C at 10°C / min.

[0070] The first PHA resin may have a melt flow index (MFI) of 0.1 g / 10 min to 20 g / 10 min at 165° C. and 5 kg, measured in accordance with ASTM D1238. For example, the melt flow index (MFI) of the first PHA resin measured in accordance with ASTM D1238 at 165°C and 5 kg may be 0.1 g / 10 min to 15 g / 10 min, 0.1 g / 10 min to 12 g / 10 min, 0.1 g / 10 min to 10 g / 10 min, 0.1 g / 10 min to 8 g / 10 min, 0.1 g / 10 min to 6 g / 10 min, 0.1 g / 10 min to 5.5 g / 10 min, 0.5 g / 10 min to 10 g / 10 min, 1 g / 10 min to 10 g / 10 min, 2 g / 10 min to 8 g / 10 min, 3 g / 10 min to 6 g / 10 min, or 3 g / 10 min to 5.5 g / 10 min.

[0071] The weight average molecular weight of the first PHA resin can be 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, 250,000 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 500,000 g / mol.

[0072] The PHA resin may also contain a second PHA resin that is a semi-crystalline PHA resin.

[0073] The second PHA resin may be a semi-crystalline PHA resin with controlled crystallinity (hereinafter referred to as scPHA resin) containing 0.1 to 30% by weight of 4-HB repeat units. For example, the second PHA resin may contain 4-HB repeat units in an amount of 0.1 to 30% by weight, 0.5 to 30% by weight, 1 to 29% by weight, 3 to 29% by weight, 1 to 28% by weight, 1.5 to 25% by weight, 2 to 20% by weight, 2.5 to 15% by weight, 3 to 25% by weight, 5 to 21% by weight, 6 to 18% by weight, 10 to 30% by weight, 10 to 20% by weight, 13 to 23% by weight, or 15 to 20% by weight.

[0074] The glass transition temperature (Tg) of the second PHA resin may be -30°C to 80°C, -30°C to 10°C, -25°C to 5°C, -25°C to 0°C, -20°C to 0°C, or -15°C to 0°C. The crystallization temperature (Tc) of the second PHA resin may be 70°C to 120°C, 75°C to 120°C, or 75°C to 115°C. The melting temperature (Tm) of the second PHA resin may be 105°C to 165°C, 110°C to 160°C, 115°C to 155°C, or 120°C to 150°C.

[0075] The second PHA resin may have a melt flow index of 0.1 g / 10 min to 15 g / 10 min at 165° C. and 5 kg, measured in accordance with ASTM D1238. For example, the melt flow index (MFI) of the second PHA resin at 165°C and 5 kg, measured in accordance with ASTM D1238, may be 0.1 g / 10 min to 10 g / 10 min, 0.2 g / 10 min to 7 g / 10 min, 0.5 g / 10 min to 5.5 g / 10 min, 0.6 g / 10 min to 5 g / 10 min, 0.8 g / 10 min to 5 g / 10 min, 1 g / 10 min to 5 g / 10 min, 0.1 g / 10 min to 5 g / 10 min, 1 g / 10 min to 6.5 g / 10 min, 1.5 g / 10 min to 15 g / 10 min, 3 g / 10 min to 10 g / 10 min, 3.5 g / 10 min to 12 g / 10 min, or 4.5 g / 10 min to 10 g / 10 min.

[0076] The weight average molecular weight of the second PHA resin can be 10,000 g / mol to 1,200,000 g / mol, 50,000 g / mol to 1,100,000 g / mol, 50,000 g / mol to 350,000 g / mol, 100,000 g / mol to 1,000,000 g / mol, 100,000 g / mol to 900,000 g / mol, 200,000 g / mol to 800,000 g / mol, 200,000 g / mol to 600,000 g / mol, 200,000 g / mol to 500,000 g / mol, or 500,000 g / mol to 1,200,000 g / mol.

[0077] The first PHA resin and the second PHA resin may be distinguished by the content of 4-HB repeating units and may have at least one property selected from the group consisting of glass transition temperature (Tg), crystallization temperature (Tc), melting temperature (Tm), and melt flow index. Specifically, the first PHA resin and the second PHA resin may be distinguished by the content of 4-HB repeating units, glass transition temperature (Tg), crystallization temperature (Tg), melting temperature (Tm), and melt flow index. For example, the content of 4-HB repeating units in the first PHA resin may be different from the content of 4-HB repeating units in the second PHA resin.

[0078] According to one embodiment of the present invention, the PHA resin may include either a first PHA resin or a second PHA resin, or may include both a first PHA resin and a second PHA resin.

[0079] Specifically, by having the PHA resin comprise a first PHA resin which is an amorphous PHA resin, or by having both a first PHA resin which is an amorphous PHA resin and a second PHA resin which is a semi-crystalline PHA resin, more specifically by adjusting the contents of the first PHA resin and the second PHA resin, the desired physical properties can be controlled more effectively.

[0080] According to one embodiment of the present invention, the PHA resin may include a first PHA resin or a second PHA resin. Specifically, the PHA resin may be composed solely of the first PHA resin or solely of the second PHA resin.

[0081] According to another embodiment of the present invention, the PHA resin may include a first PHA resin and a second PHA resin. In this case, the weight ratio of the first PHA resin to the second PHA resin may be 1:0.5-5. For example, the weight ratio of the first PHA resin to the second PHA resin may be 1:0.5-4.5, 1:0.6-4.2, or 1:0.7-3.5. When the weight ratio of the first PHA resin to the second PHA resin satisfies the above range, desired physical properties can be more effectively controlled.

[0082] The glass transition temperature (Tg) of the PHA resin may be -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.

[0083] The crystallization temperature (Tc) of the PHA resin may not be measured or may be 60°C to 120°C, 60°C to 110°C, 70°C to 120°C, 75°C to 120°C, 75°C to 115°C, 75°C to 110°C, or 90°C to 110°C.

[0084] The melting temperature (Tm) of the PHA resin may not be measurable, but may be 100°C to 170°C, 105°C to 170°C, 105°C to 165°C, 110°C to 160°C, 115°C to 155°C, 110°C to 150°C, 120°C to 150°C, or 120°C to 140°C.

[0085] The PHA resin may have a decomposition temperature (Td, 5% weight loss) measured by a thermogravimetric analyzer (TGA) of 220°C to 280°C, 245°C to 275°C, 255°C to 270°C, or 260°C to 270°C.

[0086] In this specification, the decomposition temperature (Td) is measured using a thermogravimetric analyzer (TGA). Specifically, the decomposition temperature (Td) of a PHA resin can be determined as the temperature at which the weight decreases by 5% from a weight change curve when the temperature is increased from room temperature to 600°C at a heating rate of 10°C / min using a thermogravimetric analyzer (TGA).

[0087] The weight-average molecular weight of the PHA resin may be 10,000 g / mol to 1,200,000 g / mol. For example, the weight-average molecular weight of the PHA resin may be 50,000 g / mol to 1,200,000 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 950,000 g / mol, 100,000 g / mol to 900,000 g / mol, 200,000 g / mol to 8 ..., 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / mol, 250,000 g / The molecular weight may be 0 g / mol to 650,000 g / mol, 200,000 g / mol to 400,000 g / mol, 300,000 g / mol to 600,000 g / mol, 500,000 g / mol to 1,200,000 g / mol, 500,000 g / mol to 1,000,000 g / mol, 550,000 g / mol to 1,050,000 g / mol, 550,000 g / mol to 900,000 g / mol, 600,000 g / mol to 900,000 g / mol, or 500,000 g / mol to 900,000 g / mol.

[0088] The PHA resin may have a crystallinity of 90% or less as measured by differential scanning calorimetry (DSC). For example, the crystallinity of the PHA resin may be 90% or less, 85% or less, 80% or less, 75% or less, or 70% or less as measured by differential scanning calorimetry.

[0089] The PHA resin may have an average particle size of 0.5 μm to 5 μm. For example, the average particle size of the PHA resin may be 0.7 μm to 4.6 μm, 1.1 μm to 4.5 μm, 1.5 μm to 4.3 μm, 2.2 μm to 4.2 μm, 2.6 μm to 4.0 μm, 2.8 μm to 3.9 μm, or 3.1 μm to 3.8 μm.

[0090] The average particle size of the PHA resin can be measured using a nanoparticle size analyzer (e.g., Zetasizer Nano ZS). Specifically, the average particle size of the PHA is measured by dynamic light scattering (DLS) using a Zetasizer Nano ZS (manufactured by Malvern Instruments) at a temperature of 25°C and a measurement angle of 175°. In this case, the peak value derived from the polydispersion index (PDI) is taken as the particle size with a confidence interval of 0.5.

[0091] The PHA resin may have a polydispersion index (PDI) of less than 2.5. For example, the PHA resin may have a dispersity index of 2.4 or less, 2.3 or less, 2.1 or less, or 2.0 or less.

[0092] Alternatively, the PHA resin may be obtained by cell disruption using a non-mechanical or chemical method. Specifically, since the PHA resin is a natural thermoplastic polyester polymer that accumulates within microbial cells and has a relatively large average particle size, it may be obtained through a disruption process to more effectively control the yield and physical properties of the desired material or to improve process efficiency.

[0093] Meanwhile, a composition for a biodegradable meltblown nonwoven fabric according to another embodiment of the present invention may contain at least one biodegradable resin selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate (PBST), polyhydroxybutyrate valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), and thermoplastic starch (TPS).

[0094] By using a biodegradable resin together with a PHA resin, the composition for biodegradable meltblown nonwoven fabrics can have excellent dispersibility and filtration efficiency in addition to the filterability, air permeability, and flexibility required for nonwoven fabrics.

[0095] The composition for biodegradable meltblown nonwoven fabrics may contain 15% by weight or more of a PHA resin, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. For example, the PHA resin content may be 20% by weight or more, 30% by weight or more, 35% by weight or more, 40% by weight or more, 50% by weight or more, 65% by weight or more, 70% by weight or more, 85% by weight or more, 90% by weight or more, or 100% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics.

[0096] The composition for biodegradable meltblown nonwoven fabrics may contain a biodegradable resin in an amount of less than 90% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. For example, the content of the biodegradable resin may be 85% by weight or less, 80% by weight or less, 70% by weight or less, 60% by weight or less, 45% by weight or less, or 35% by weight or less. Specifically, the content of the biodegradable resin may be 35% by weight to 80% by weight, but is not limited thereto.

[0097] According to another embodiment of the present invention, the weight ratio of PHA resin to biodegradable resin may be 1:99 to 99:1. For example, the weight ratio of PHA resin to biodegradable resin may be 5:95 to 99:5, 10:90 to 90:10, 15:90 to 60:40, 5:95 to 45:55, 10:90 to 40:60, 15:85 to 35:65, or 20:80 to 30:70. When the weight ratio of PHA resin to biodegradable resin satisfies the above range, properties such as filterability, air permeability, and flexibility can be improved without compromising biodegradability and processability, and the uniformity of the diameter of fibers produced under high-temperature, high-pressure conditions such as the meltblown method can be improved.

[0098] Specifically, the biodegradable resin may be polylactic acid (PLA). More specifically, the weight ratio of PHA resin to PLA resin may be 10:90 to 70:30. For example, the weight ratio of PHA resin to PLA resin may be 10:90 to 45:55, 15:85 to 40:60, 15:85 to 35:65, or 20:80 to 30:70. When the weight ratio of PHA resin to PLA resin satisfies the above range, properties such as filterability, air permeability, and flexibility can be improved, as well as the uniformity of the diameter of fibers produced under high-temperature, high-pressure conditions such as a melt-blown method, without compromising biodegradability and processability.

[0099] According to another embodiment of the present invention, the composition for biodegradable meltblown nonwoven fabric may further comprise at least one additive selected from the group consisting of pigments, dye absorbers, light absorbers, antioxidants, compatibilizers, bulking agents, nucleating agents, melt strength agents, slip agents, and fluidizing agents.

[0100] The pigment may include at least one selected from the group consisting of inorganic particles, carbon black, and cobalt green. The inorganic particles may be, but are not limited to, metal particles such as Cu, metal oxides, metalloid oxides, or combinations thereof.

[0101] The pigment may be further blended in an amount of 0.01% by weight to 20% by weight, 0.01% by weight to 15% by weight, 0.01% by weight to 12% by weight, 0.01% by weight to 10% by weight, 0.01% by weight to 8% by weight, 0.01% by weight to 5% by weight, 0.2% by weight to 4.5% by weight, 0.2% by weight to 4% by weight, or 0.5% by weight to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics.

[0102] The antioxidant is an additive for preventing decomposition by ozone or oxygen, preventing oxidation during storage, or preventing deterioration of physical properties. Conventional antioxidants may be used as long as they do not impair the effects of the present invention.

[0103] Specifically, the antioxidant may include at least one selected from the group consisting of hindered phenol-based antioxidants and phosphite (phosphorus-based) antioxidants.

[0104] The hindered phenol-based antioxidant may include, for example, at least one selected from the group consisting of 4,4'-methylenebis(2,6-di-t-butylphenol), octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], and 3,9-bis[2-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane.

[0105] The phosphite (phosphorus) antioxidant may include at least one selected from the group consisting of, for example, tris-(2,4-di-t-butylphenyl)phosphite, bis-(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis-(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, distearyl-pentaerythritol diphosphite, [bis(2,4-di-t-butyl-5-methylphenoxy)phosphino]biphenyl, and N,N-bis[2-[[2,4,8,10-tetrakis(1,1-dimethylethyl)dibenzo[d,f][1,3,2]dioxyphosphepin-6-yl]oxy]-ethyl]ethanamine.

[0106] The antioxidant may be further blended in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. When the content of the antioxidant satisfies the above range, the physical properties of the nonwoven fabric are improved, and the desired effects of the present invention may be more effectively achieved.

[0107] The compatibilizer is an additive that imparts compatibility by eliminating the mold releasability of the biodegradable resin and / or PHA resin. A general compatibilizer may be used as long as it does not impair the effects of the present invention.

[0108] Specifically, the compatibilizer may include at least one selected from the group consisting of polyvinyl acetate (PVAc), isocyanate, polypropylene carbonate, glycidyl methacrylate, ethylene vinyl alcohol, polyvinyl alcohol (PVA), ethylene vinyl acetate, maleic anhydride, and glycerin stearate.

[0109] The compatibilizer may be further contained in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By using a compatibilizer in an amount within the above range, the compatibility between the resins used is increased, improving physical properties, and the desired effects of the present invention may be more advantageously achieved.

[0110] The extender is an inorganic material and additive for increasing the crystallization rate of the synthetic resin during the molding process, thereby improving moldability, and for reducing the problem of rising costs due to the use of highly biodegradable resins. General inorganic materials may be used as long as they do not impair the effects of the present invention.

[0111] The bulking agent may contain at least one selected from the group consisting of inorganic materials such as zinc and calcium, stearic acid, light or heavy calcium carbonate, silica, talc, kaolin, barium sulfate, clay, calcium oxide, magnesium hydroxide, titanium oxide, carbon black, and glass fiber.

[0112] The average particle size of the bulking agent may be 0.5 μm to 5 μm. For example, the average particle size of the bulking agent may be 0.5 μm to 4.8 μm, 0.5 μm to 4.5 μm, or 0.7 μm to 4 μm. If the average particle size of the bulking agent is less than 0.5 μm, it is difficult to disperse the particles. If it exceeds 5 μm, the particle size becomes too large, which may impair the effects of the present invention.

[0113] The filler may be used in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By using a filler content within the above range, it can be advantageous in terms of further achieving the desired effects of the present invention.

[0114] Nucleating agents are additives that complement or change the crystalline morphology of polymers and increase the crystallization (solidification) rate when the polymer melt is cooled. In particular, the PHA resin used in the present invention has a slow crystallization rate, which can make the process difficult to carry out due to the slow crystallization rate. To solve this problem, the use of this type of nucleating agent increases the crystallization rate, further improving processability, moldability, and productivity, and effectively achieving desired physical properties.

[0115] A conventional nucleating agent may be used as long as it does not impair the effects of the present invention. Specifically, the nucleating agent may include, for example, a metal compound consisting of a simple substance (pure substance) or a composite oxide, a low-molecular-weight organic compound having a metal carboxylate group, a high-molecular-weight organic compound having a metal carboxylate group, a high-molecular-weight organic compound, phosphoric acid or phosphorous acid or a metal salt thereof, a sorbitol derivative, thioglycolic anhydride, and p-toluenesulfonic acid or a metal salt thereof. The above nucleating agents may be used alone or in combination of two or more.

[0116] The metal compound consisting of a simple substance (pure substance) or a composite oxide may be at least one selected from the group consisting of carbon black, calcium carbonate, synthetic silicic acid and its salts, silica, zinc white, clay, sulphuric acid, basic magnesium carbonate, mica, talc, quartz powder, diatomaceous earth, dolomite powder, titanium oxide, zinc oxide, antimony oxide, barium sulfate, calcium sulfate, alumina, calcium silicate, metal salts of organic phosphorus, and boron nitride.

[0117] The low molecular weight organic compound having a metal carboxylate group may be at least one selected from the group consisting of, 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, benzoic acid, p-tert-butylbenzoic acid, terephthalic acid, terephthalic acid monomethyl ester, isophthalic acid, and metal salts of isophthalic acid monomethyl ester.

[0118] The polymeric organic compound having a metal carboxylate group may be at least one selected from the group consisting of, for example, a metal salt of carboxylic acid group-containing polyethylene obtained by oxidation of polyethylene, a carboxylic acid group-containing polypropylene obtained by oxidation of polypropylene, a copolymer of acrylic acid or methacrylic acid with an olefin (ethylene, propylene, butene-1, etc.), a copolymer of acrylic acid or methacrylic acid with styrene, a copolymer of an olefin and maleic anhydride, and a copolymer of styrene and maleic anhydride.

[0119] The polymeric organic compound may be, for example, at least one selected from the group consisting of α-olefins having a branch at the third carbon atom and having 5 or more carbon atoms (3,3-dimethylbutene-1,3-methylbutene-1,3-methylpentene-1,3-methylhexene-1,3-methylhexene-1, 3,5,5-trimethylhexene-1, etc.), vinylcycloalkane polymers (vinylcyclopentane, vinylcyclohexane, vinylnorbornane, etc.), polyalkylene glycols (polyethylene glycol, polypropylene glycol, etc.), poly(glycolic acid), cellulose, cellulose ester, and cellulose ether.

[0120] The phosphoric acid or phosphorous acid or metal salt thereof may be at least one selected from the group consisting of diphenyl phosphate, diphenyl phosphite, bis(4-tert-butylphenyl)phosphate, and metal salts of methylene bis(2,4-tert-butylphenyl)phosphate. Examples of sorbitol derivatives include bis(p-methylbenzylidene)sorbitol and bis(p-ethylbenzylidene)sorbitol.

[0121] The nucleating agent may be further blended in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By adjusting the content of the nucleating agent within the above ranges, the crystallization rate can be increased, thereby improving processability. For example, by increasing the crystallization rate in the cutting step for producing pellets in the preparation step, productivity and moldability can be further improved.

[0122] The melt strength agent is an additive for increasing the melt strength of the reaction product. Conventional melt strength agents may be used as long as they do not impair the effects of the present invention.

[0123] Specifically, the melt strength agent may include at least one selected from the group consisting of polyester, styrene-based polymer (such as acrylonitrile butadiene styrene or polystyrene), polysiloxane, organo-modified siloxane polymer, and maleic anhydride-ethylene propylene diene monomer conjugate (MAH-g-EPDM).

[0124] The melt strength agent may be further included in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By ensuring that the content of the melt strength agent satisfies the above range, the desired effects of the present invention may be more easily achieved.

[0125] The slip agent is an additive that enhances the slipperiness (ease of sliding) during extrusion and prevents the fiber surfaces from sticking together. Specifically, a conventional slip agent may be used as long as it does not impair the effects of the present invention. For example, the slip agent may be at least one selected from the group consisting of erucamide, olamide, and stearamide.

[0126] The slip agent may be further blended in an amount of 0.01 to 20% by weight, 0.01 to 15% by weight, 0.01 to 12% by weight, 0.01 to 10% by weight, 0.01 to 8% by weight, 0.01 to 5% by weight, 0.2 to 4.5% by weight, 0.2 to 4% by weight, or 0.5 to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By incorporating the slip agent in an amount within the above ranges, processability, productivity, and moldability may be further improved, which may be advantageous in terms of further achieving the desired effects of the present invention.

[0127] The composition for biodegradable meltblown nonwoven fabrics may further contain a crosslinking agent and / or a stabilizer as an additive.

[0128] The crosslinking agent is an additive for changing the properties of the PHA resin and increasing the molecular weight of the resin. Conventional crosslinking agents may be used as long as they do not impair the effects of the present invention.

[0129] For example, the crosslinking agent may be at least one selected from the group consisting of fatty acid esters, natural oils having epoxy groups (epoxidized natural oils), diallyl phthalate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, diethylene glycol dimethacrylate, and bis(2-methacryloxyethyl)phosphate.

[0130] The crosslinking agent may be further blended in an amount of 0.01% by weight to 20% by weight, 0.01% by weight to 15% by weight, 0.01% by weight to 12% by weight, 0.01% by weight to 10% by weight, 0.01% by weight to 8% by weight, 0.01% by weight to 5% by weight, 0.2% by weight to 4.5% by weight, 0.2% by weight to 4% by weight, or 0.5% by weight to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics.

[0131] The stabilizer may be at least one selected from the group consisting of trimethyl phosphate, triphenyl phosphate, trimethylphosphine, phosphoric acid, and phosphorous acid.

[0132] The stabilizer may be present in an amount of 0.01% to 20% by weight, 0.01% to 15% by weight, 0.01% to 12% by weight, 0.01% to 10% by weight, 0.01% to 8% by weight, 0.01% to 5% by weight, 0.2% to 4.5% by weight, 0.2% to 4% by weight, or 0.5% to 3% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics.

[0133] As used herein, additives may be in the form of, but are not limited to, a monomer, a polymer, or a copolymer.

[0134] According to another embodiment of the present invention, the composition for a biodegradable meltblown nonwoven fabric may further contain biomass.

[0135] The inclusion of biomass in the composition for biodegradable meltblown nonwoven fabrics can enhance biodegradability and improve soil quality. That is, biomass has excellent biodegradability, is easily decomposed when not decomposed, serves as fertilizer, and improves soil strength, thereby improving soil quality.

[0136] The biomass may be used in an amount of 5 to 50% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. Specifically, the biomass content may be 10 to 48%, 15 to 48%, 20 to 45%, 20 to 43%, or 20 to 40% by weight, based on the total weight of the composition for biodegradable meltblown nonwoven fabrics. By ensuring that the biomass content satisfies the above ranges, biodegradability is further improved, soil improvement effects are achieved, and crosslinking strength with the PHA resin is improved, allowing the desired effects of the present invention to be more effectively achieved.

[0137] The composition for biodegradable meltblown nonwoven fabrics may have a melt flow index of 10 g / 10 min to 30 g / 10 min at 190°C and 2.16 kg, measured in accordance with ASTM D 1238. For example, the melt flow index of the composition for biodegradable meltblown nonwoven fabrics, measured in accordance with ASTM D 1238 at 190°C and 2.16 kg, may be 10 g / 10 min to 25 g / 10 min, 11 g / 10 min to 20 g / 10 min, or 12 g / 10 min to 18 g / 10 min.

[0138] The composition for biodegradable meltblown nonwoven fabrics may have a melt flow index of 30 g / 10 minutes or more at 210°C under 2.16 kg, as measured in accordance with ASTM D 1238. For example, the melt flow index of the composition for biodegradable meltblown nonwoven fabrics at 210°C under 2.16 kg, as measured in accordance with ASTM D 1238, may be 45 g / 10 minutes or more, 50 g / 10 minutes or more, 53 g / 10 minutes or more, 55 g / 10 minutes or more, 59 g / 10 minutes or more, 65 g / 10 minutes or more, 80 g / 10 minutes or more, 90 g / 10 minutes or more, or 100 g / 10 minutes or more.

[0139] The melt flow index measured for the biodegradable meltblown nonwoven composition according to ASTM D1238 may be measured for pellets prepared for the biodegradable meltblown nonwoven composition according to ASTM D1238.

[0140] Specifically, the melt flow index may be measured in accordance with ASTM D 1238 for biodegradable pellets prepared by feeding a composition for biodegradable meltblown nonwoven fabrics into a twin-screw compounder, kneading the composition, and melt-extruding the mixture. More specifically, the screw rotation speed of the twin-screw compounder may be set to 200 rpm, and the composition for biodegradable meltblown nonwoven fabrics may be kneaded while increasing the internal temperature from 50°C to 170°C, followed by melt-extrusion at a pressure of 12 bar and a temperature of 177°C, followed by preparation of biodegradable pellets using an underwater cutter system.

[0141] The biodegradable meltblown nonwoven fabric composition may have a weight average molecular weight of 500,000 g / mol or less. For example, the weight average molecular weight of the biodegradable meltblown nonwoven fabric composition may be 450,000 g / mol or less, 400,000 g / mol or less, or 350,000 g / mol or less.

[0142] The biodegradable meltblown nonwoven fabric composition may have a weight average molecular weight of 500,000 g / mol or less. For example, the weight average molecular weight of the biodegradable meltblown nonwoven fabric composition may be 450,000 g / mol or less, 400,000 g / mol or less, or 350,000 g / mol or less.

[0143] The composition for biodegradable meltblown nonwoven fabrics may have a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of -35°C to 15°C, -25°C to 5°C, -20°C to 1°C, -20°C to -5°C, or -20°C to -10°C, a melting temperature (Tm) of 105°C to 200°C, 106°C to 195°C, 110°C to 180°C, 130°C to 180°C, 150°C to 180°C, or 170°C to 180°C, and a crystallization temperature (Tc) that is not measured or is 50°C to 120°C, 65°C to 100°C, or 75°C to 95°C.

[0144] The composition for biodegradable meltblown nonwoven fabrics may have a decomposition temperature (Td, 5% weight loss) measured by a thermogravimetric analyzer (TGA) of 220°C or higher, 230°C or higher, 240°C or higher, 250°C or higher, or 260°C or higher, or 220°C to 300°C, 240°C to 300°C, 250°C to 300°C, or 260°C to 300°C.

[0145] Biodegradable Meltblown Nonwoven Fabric Another embodiment of the present invention provides a biodegradable meltblown nonwoven fabric comprising biodegradable fibers, the biodegradable fibers comprising a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and the biodegradable fibers have an average diameter of 10 μm or less and a standard deviation of the average diameter of 1.3 or less.

[0146] The biodegradable meltblown nonwoven fabric may be prepared using a composition for a biodegradable meltblown nonwoven fabric. Details of the PHA resin are as described above.

[0147] The biodegradable meltblown nonwoven fabric may have a filtration efficiency of 8% or more at 0.3 μm and 10% or more at 0.5 μm, in accordance with KS K ISO 9073-152007.

[0148] For example, the biodegradable meltblown nonwoven fabric may have a filtration efficiency at 0.3 μm in accordance with KS K ISO 9073-152007 of 8% or more, 9% or more, 10% or more, 12% or more, 14% or more, 18% or more, 20% or more, 24% or more, 30% or more, 36% or more, 45% or more, 50% or more, or 57% or more.

[0149] The biodegradable meltblown nonwoven fabric may also have a filtration efficiency at 0.5 μm in accordance with KS K ISO 9073-152007 of 10% or more, 11% or more, 20% or more, 26% or more, 30% or more, 32% or more, 36% or more, 38% or more, 41% or more, 44% or more, 45% or more, 50% or more, 55% or more, 60% or more, 65% or more, or 70% or more.

[0150] The biodegradable meltblown nonwoven fabric may have a total thickness of 0.05 mm to 20 mm. For example, the total thickness of the biodegradable meltblown nonwoven fabric may be 0.06 mm to 20 mm, 0.08 mm to 15 mm, 0.1 mm to 10 mm, or 0.1 mm to 8 mm.

[0151] The basis weight of the biodegradable meltblown nonwoven fabric may be 10 gsm to 500 gsm. For example, the basis weight of the biodegradable meltblown nonwoven fabric may be 12 gsm to 450 gsm, 15 gsm to 400 gsm, 20 gsm to 350 gsm, 20 gsm to 250 gsm, or 25 gsm to 200 gsm.

[0152] The biodegradable meltblown nonwoven fabric may have a warp strength of 30 N or more per 120 gsm basis weight and a warp elongation of 10% or more in accordance with K ISO 9073-3:1989. For example, the biodegradable meltblown nonwoven fabric may have a warp strength of 33 N or more, 35 N or more, or 36 N or more and a warp elongation of 11% or more, 13% or more, 15% or more, 18% or more, or 20% or more in accordance with K ISO 9073-3:1989, based on a basis weight of 120 gsm (thickness: 0.28 mm).

[0153] The biodegradable meltblown nonwoven fabric may have a warp strength of 20 N or more and a warp elongation of 4% or more for a basis weight of 60 gsm in accordance with K ISO 9073-3: 1989. For example, the biodegradable meltblown nonwoven fabric may have a warp strength of 21 N or more, 23 N or more, or 25 N or more and a warp elongation of 4.5% or more, 6% or more, 7% or more, or 8% or more for a basis weight of 60 gsm (thickness: 0.24 mm) in accordance with K ISO 9073-3: 1989.

[0154] The biodegradable meltblown nonwoven fabric may have a warp strength of 3N or more and a warp elongation of 6% or more for a basis weight of 30 gsm according to K ISO 9073-3: 1989. For example, the biodegradable meltblown nonwoven fabric may have a warp strength of 3.5N or more, 5N or more, 6N or more, 7N or more, 8N or more, or 9N or more for a basis weight of 30 gsm (thickness: 0.12 mm) according to K ISO 9073-3: 1989, and a warp elongation of 6.5% or more, 7% or more, 8% or more, or 9% or more.

[0155] The biodegradable meltblown nonwoven fabric may also be an aggregate of biodegradable fibers.

[0156] Specifically, the biodegradable fibers have an average diameter of 10 μm or less and a standard deviation of the average diameter of 1.3 or less. For example, the average diameter of the biodegradable fibers may be 8 μm or less, 6 μm or less, 5 μm or less, 4.5 μm or less, 4 μm or less, 3.5 μm or less, 2.5 μm or less, 2.3 μm or less, 2.2 μm or less, 2 μm or less, 1.9 μm or less, or 1.7 μm or less. The standard deviation of the average diameter may be 1.2 or less, 1.1 or less, 1 or less, 0.85 or less, or 0.6 or less.

[0157] The biodegradable fiber may also have an elongation of 500% or less, 350% or less, 200% or less, 130% or less, 100% or less, 90% or less, 80% or less, or 75% or less.

[0158] According to another embodiment of the present invention, the biodegradable fiber may be a bicomponent fiber with a different cross section, or a bicomponent fiber with two or more components, or three or more components.

[0159] The heterogeneous cross-section fibers may be, but are not limited to, circular, elliptical, or polygonal in cross-section.

[0160] The biodegradable fiber may be of a sheath-core type having a core and a sheath, a side-by-side type, a sea-island type, or a segmented pie type.

[0161] In the sheath-core type, the cross section of the core and the cross section of the sheath may be different. For example, the cross section of the core may be circular and the cross section of the sheath may be doughnut-shaped, but this is not limitative.

[0162] The biodegradable fiber may also be a bicomponent fiber in which the sheath and core of the fiber portion of the fiber each contain different monofilament resins. For example, the fiber may be a ternary composite fiber in which the sheath is made of a single resin and the core is made of at least two resin components, or a ternary composite fiber in which the core is made of a single resin and the sheath is made of at least two resin components. The biodegradable fiber may also be a bicomponent fiber in which the sheath and core are each made of at least two resin components.

[0163] For example, the core may be made of a PHA resin, and the sheath may be made of a biodegradable resin. For example, the biodegradable resin may be at least one selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate (PBST), polyhydroxybutyrate valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), polybutylene ethylene adipate succinate (PBEAS), polybutylene ethylene succinate (PBES), and thermoplastic starch (TPS).

[0164] The weight ratio of the core to the sheath may be 5:95 to 95:5. For example, the weight ratio of the core to the sheath may be 5:95 to 85:15, 7:93 to 80:20, 10:90 to 75:25, or 10:90 to 70:30.

[0165] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may be electrostatically treated.

[0166] Electrostatic treatment is a method that can enhance the cohesion ability of nonwoven fabrics by charging them with static electricity. By subjecting nonwoven fabrics to electrostatic treatment, the fibers that make up the nonwoven fabric are forcibly charged, and nonwoven fabrics made of fibers with polarized charges can easily collect charged fine particles.

[0167] The electrostatic treatment process may be carried out using, but is not limited to, corona discharge, plasma charging, tribocharging, or water charging with high pressure water droplets.

[0168] To maximize the electrostatic effect, a charging agent may also be used, which may be, but is not limited to, a hindered amine charging agent.

[0169] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further have a functional coating layer on at least one surface.

[0170] For example, the functional coating layer may be a hard coat layer or an antibacterial coating layer, and an adhesive layer may be interposed between the functional coating layer and the biodegradable meltblown nonwoven fabric.

[0171] At least one surface of the biodegradable meltblown nonwoven fabric may be subjected to an ion or electrical surface treatment, such as, but not limited to, ion coating, ion plunging, electroplating, or voltage plating.

[0172] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further include a biodegradable spunbond nonwoven fabric on at least one side.

[0173] The biodegradable meltblown nonwoven fabric may further contain one or more additives selected from the group consisting of a deodorant, an antibacterial agent, an inorganic filler, and a lubricant.

[0174] The deodorizing agent may be, for example, at least one metal oxide selected from the group consisting of titanium dioxide (TiO2), zinc oxide (ZnO), tin oxide (SnO2), zirconium dioxide (ZrO), and strontium titanate (SrTiO3), but is not limited thereto.

[0175] The deodorizing agent may be used in an amount of 0.01 to 20% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric. For example, the deodorizing agent may be used in an amount of 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric.

[0176] The antibacterial agent may be at least one selected from the group consisting of nanosilver, nanocopper, nanozinc, and zeolite-based antibacterial agents, but is not limited thereto.

[0177] The antibacterial agent may be employed in an amount of 0.01 to 20% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric. For example, the antibacterial agent may be employed in an amount of 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric.

[0178] The inorganic filler may include, but is not limited to, at least one selected from the group consisting of talc, barium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, zinc oxide, magnesium oxide, alumina, and silica.

[0179] The inorganic filler may have an average particle size of 0.01 μm to 2.0 μm. For example, the average particle size of the inorganic filler may be 0.01 μm to 2.0 μm, 0.05 μm to 2.0 μm, or 0.05 μm to 1.5 μm.

[0180] The inorganic filler may be used in an amount of 0.01 to 20% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric. For example, the inorganic filler may be used in an amount of 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric.

[0181] The lubricant may be a fatty acid ester, specifically, a glycerin fatty acid ester, a sorbitan fatty acid ester, a pyridoxine fatty acid ester, or a mixture of at least one selected from these, but is not limited thereto.

[0182] The lubricant may be used in an amount of 0.01 to 20% by weight, based on the total weight of the composition for a biodegradable meltblown nonwoven fabric. For example, the lubricant may be used in an amount of 0.01 to 20% by weight, 0.05 to 15% by weight, or 0.1 to 10% by weight, based on the total weight of the biodegradable meltblown nonwoven fabric. Manufacturing method of biodegradable meltblown nonwoven fabric A method for producing a biodegradable meltblown nonwoven fabric according to another embodiment of the present invention includes melt-extruding a composition for a biodegradable meltblown nonwoven fabric or pellets produced therefrom, followed by spinning, wherein the composition for the biodegradable meltblown nonwoven fabric comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units and has a melt flow index (MFI) of 30 g / 10 min or more, as measured at 210°C and 2.16 kg in accordance with ASTM D1238.

[0183] Details of the composition for biodegradable meltblown nonwoven fabric are as described above.

[0184] Specifically, in a method for producing a biodegradable meltblown nonwoven fabric according to another aspect of the present invention, the composition for a biodegradable meltblown nonwoven fabric may be directly fed to an apparatus for spinning, or pellets prepared by melt-extruding the composition for a biodegradable meltblown nonwoven fabric may be fed to an apparatus for spinning to prepare a biodegradable meltblown nonwoven fabric.

[0185] According to another embodiment of the present invention, a biodegradable meltblown nonwoven fabric may be produced by melt-extruding and melt-spinning the composition for a biodegradable meltblown nonwoven fabric at 150 to 230°C. For example, the temperatures for melt-extrusion and melt-spinning may be 160 to 225°C, 180 to 220°C, or 195 to 215°C.

[0186] In such cases, conventional melt spinning equipment may be used, including, but not limited to, a melt blown melt spinning equipment based on a single helix extruder.

[0187] The meltblown spinning apparatus may also include a melting section, a nozzle section equipped with a filter, a draft section between the nozzle hole and a take-up roller, and a take-up section. By controlling the melting temperature, nozzle hole diameter, nozzle hole length, nozzle hole diameter-to-length ratio, nozzle inner filter size, discharge amount from the nozzle, length of the draft section, number of revolutions, cooling temperature, and take-up speed of the meltblown spinning apparatus, a biodegradable meltblown nonwoven fabric having desired physical properties can be produced.

[0188] The spinning step may be carried out so as to adjust the basis weight of the produced biodegradable meltblown nonwoven fabric to 10 gsm to 500 gsm. For example, the spinning step may be carried out so as to adjust the basis weight of the produced biodegradable meltblown nonwoven fabric to 12 gsm to 450 gsm, 15 gsm to 400 gsm, 20 gsm to 350 gsm, 20 gsm to 250 gsm, 25 gsm to 200 gsm, 25 gsm to 150 gsm, 25 gsm to 100 gsm, or 25 gsm to 50 gsm.

[0189] According to another embodiment of the present invention, the composition for biodegradable meltblown nonwoven fabric may be melt-extruded at a pressure of 6 bar to 30 bar and a temperature of 150 to 200°C to prepare pellets, which are then melt-spun at 150 to 230°C to prepare a biodegradable meltblown nonwoven fabric.

[0190] For example, the composition for a biodegradable meltblown nonwoven fabric may be melt-extruded at a pressure of 7 to 28 bar or 8 to 26 bar and a temperature of 155 to 190°C or 165 to 185°C, cooled to 15°C or below, 10°C or below, or 6°C or below, and cut into pellets. These pellets may be melt-spun at 160 to 225°C, 180 to 220°C, or 195 to 215°C to produce a biodegradable meltblown nonwoven fabric.

[0191] Furthermore, before the step of melt-spinning the pellets, a step of drying the pellets at 40°C to 58°C or 42°C to 60°C for 11 hours or more or 12 hours or more may be further carried out.

[0192] The drying step may be carried out until the resin moisture content of the pellets is 2,000 ppm or less, 1,500 ppm or less, 1,100 ppm or less, 500 ppm or less, 300 ppm or less, 150 ppm or less, 100 ppm or less, 60 ppm or less, or 50 ppm or less, and may be carried out by hot air drying or dehumidifying drying, but is not limited to these.

[0193] According to another embodiment of the present invention, the step of spinning the composition for a biodegradable meltblown nonwoven fabric may be performed using a composite spinning apparatus. For example, the composite spinning apparatus may be a sheath-core composite spinning apparatus.

[0194] Specifically, the composition for a biodegradable meltblown nonwoven fabric may be prepared by directly charging the composition for a biodegradable meltblown nonwoven fabric into the core or sheath of the sheath-core composite spinning device.

[0195] More specifically, the composition for a biodegradable meltblown nonwoven fabric may be supplied to the core or sheath, or a biodegradable resin containing at least one selected from the group consisting of PBAT (polybutylene adipate terephthalate), PLA (polylactic acid), PBS (polybutylene succinate), PBA (polybutylene adipate), PBSA (polybutylene succinate adipate), PBST (polybutylene succinate terephthalate), PHBV (polyhydroxybutyrate valerate), PCL (polycaprolactone), PBSAT (polybutylene succinate adipate terephthalate), PBEAS (polybutylene ethylene adipate succinate), PBES (polybutylene ethylene succinate), and TPS (thermoplastic starch) may be supplied to the core or sheath.

[0196] For example, the above-mentioned composition for a biodegradable meltblown nonwoven fabric may be applied to the core, and a biodegradable resin containing at least one selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate (PBST), polyhydroxybutyrate valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), polybutylene ethylene adipate succinate (PBEAS), polybutylene ethylene succinate (PBES), and thermoplastic starch (TPS) may be applied to the sheath.

[0197] The weight ratio of the raw materials supplied to the sheath relative to the core may be 5:95 to 95:5, 5:95 to 85:15, 7:93 to 80:20, 10:90 to 75:25, or 10:90 to 70:30.

[0198] Mode of Invention The present invention will be described in more detail below with reference to examples. However, the following examples are for the purpose of illustrating the present invention and are not intended to limit the scope of the present invention. [Example]

[0199] Fabrication of biodegradable meltblown nonwoven fabrics Example 1 A biodegradable meltblown nonwoven fabric composition was prepared by mixing 30 wt% of a polyhydroxyalkanoate (PHA) resin (3-HB-co-4-HB, manufacturer: CJ) consisting of a first PHA resin (aPHA, 4-hydroxybutyric acid (4-HB) content: 33 wt%, weight-average molecular weight (Mw): 600,000 g / mol, melt flow index at 165°C and 5 kg: 5.5 g / 10 min according to ASTM D1238) with 70 wt% polylactic acid (PLA), and adding 1 phr of polyvinyl acetate (PVAc, manufacturer: Wacker). Here, phr (per hundred resin) refers to the unit of input amount of material added per 100 parts by weight of polymer (1 phr: 1 g of material added per 100 g of polymer).

[0200] The composition for biodegradable meltblown nonwoven fabric was melt-extruded and spun through a nozzle to prepare a biodegradable meltblown nonwoven fabric (basis weight: 30 gsm), which was then subjected to electrostatic treatment under the following specific treatment conditions: -Melt spinning temperature: 210℃ -Nozzle: Ψ0.25, 21 pieces, 5mm (hole spacing) -Discharge rate: 6ml / min -Process air flow rate: 1,000 L / min -Process air temperature: 260℃ -DCD (nozzle-collector distance): 250mm - Belt movement speed (winding speed): 2.3 m / min Examples 2 to 15 and Comparative Examples 1 to 2 Biodegradable meltblown nonwoven fabrics were produced in the same manner as in Example 1, except that the ingredients and process conditions were changed as shown in Table 1. A polyhydroxyalkanoate (PHA) resin (3-HB-co-4-HB, manufacturer: CJ) consisting of a second PHA resin (scPHA, 4-hydroxybutyric acid (4-HB) content: 6 wt %, weight average molecular weight (Mw): 410,000 g / mol, melt flow index at 165°C and 5 kg according to ASTM D1238: 2.88 g / 10 min) was used in Examples 6, 7, and 12.

[0201] [Table 1]

[0202] [Test example] Test Example 1: Melt Flow Index The melt flow index (g / 10 min) of the compositions for biodegradable meltblown nonwoven fabrics prepared in Examples 8, 10 to 12, and 14 was measured at 190°C and 2.16 kg or 210°C and 2.16 kg in accordance with ASTM D1238.

[0203] Specifically, the composition for biodegradable meltblown nonwoven fabrics was charged into a twin-screw compounder, kneaded, and melt-extruded to obtain biodegradable pellets, and the melt flow index was measured in accordance with ASTM D1238. Test Example 2: Tg and Tm The glass transition temperature (Tg) and melting temperature (Tm) of the compositions for biodegradable meltblown nonwoven fabrics prepared in Examples 8, 10 to 12, and 14 were measured using differential scanning calorimetry (DSC).

[0204] Specifically, 5 mg to 20 mg of each biodegradable meltblown nonwoven fabric composition was placed in an aluminum pan, and the temperature was increased from 40°C to 180°C at 10°C / min using a differential scanning calorimeter, and then the temperature was cooled to -50°C at the same rate of 10°C / min to obtain a heat flow curve, from which the glass transition temperature (Tg) and melting temperature (Tm) were measured. Test Example 3: Td The decomposition temperature (Td) of the compositions for biodegradable meltblown nonwoven fabrics prepared in Examples 8, 10 to 12, and 14 was measured using a thermogravimetric analyzer (TGA).

[0205] Specifically, using a thermogravimetric analyzer (TGA), the temperature was raised from room temperature to 600°C at a heating rate of 10°C / min, and from the weight change curve obtained, the temperature at which the weight of each biodegradable fiber composition decreased by 5% was measured as the decomposition temperature (Td).

[0206] [Table 2]

[0207] Test Example 4: Diameter and standard deviation of biodegradable fibers For each of the biodegradable meltblown nonwoven fabrics produced in Examples 1 to 15 and Comparative Examples 1 and 2, the diameters of the fibers constituting the biodegradable meltblown nonwoven fabric were measured using a scanning electron microscope (SEM), and the standard deviation was calculated. Test Example 5: Filtration efficiency of biodegradable meltblown nonwoven fabric The biodegradable meltblown nonwoven fabrics produced in Examples 1 to 15 and Comparative Examples 1 and 2 were measured to determine the area of ​​the fabric. 2 The filtration efficiency of 0.3 μm and 0.5 μm particles was measured in accordance with KS K ISO 9073-152007 under conditions of 200 Pa and a pressure of 200 Pa. Specifically, particles with average particle sizes of 0.3 μm and 0.5 μm were sprayed onto the nonwoven fabric, and the filtration efficiency was measured.

[0208] [Table 3]

[0209] As shown in Table 3 above, the biodegradable meltblown nonwoven fabrics of Examples 1 to 15 had the average diameter and standard deviation of the fibers constituting them each within the desired range, and the filtration efficiency of the nonwoven fabric was also excellent.

[0210] Figure 1 is a scanning electron microscope (SEM, 100x magnification) image of the biodegradable meltblown nonwoven fabric of Example 14. Figure 2 is a scanning electron microscope (SEM, 1,000x magnification) image of the biodegradable meltblown nonwoven fabric of Example 14.

[0211] As shown in Figures 1 and 2, the biodegradable meltblown nonwoven fabric of Example 14 had excellent uniformity in the diameter of the constituent fibers.

Claims

1. A composition for biodegradable meltblown nonwoven fabrics, comprising a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, and having a melt flow index (MFI) of 30 g / 10 min or more as measured at 210°C and 2.16 kg in accordance with ASTM D1238.

2. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, wherein the PHA resin contains 0.1% by weight to 60% by weight of the 4-hydroxybutyric acid (4-HB) repeating unit.

3. 2. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, wherein the PHA resin comprises a first PHA resin, the first PHA resin contains 15% by weight to 60% by weight of 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index (MFI) of 0.1 g / 10 min to 20 g / 10 min when measured at 165°C and 5 kg in accordance with ASTM D1238.

4. 2. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, wherein the PHA resin comprises a second PHA resin, the second PHA resin contains 0.1% by weight to 30% by weight of 4-hydroxybutyric acid (4-HB) repeating units, and has a melt flow index of 0.1 g / 10 min to 15 g / 10 min when measured at 165°C and 5 kg in accordance with ASTM D1238.

5. 2. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, wherein the composition for biodegradable meltblown nonwoven fabrics comprises at least one biodegradable resin selected from the group consisting of polybutylene adipate terephthalate (PBAT), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene adipate (PBA), polybutylene succinate adipate (PBSA), polybutylene succinate terephthalate (PBST), polyhydroxybutyrate valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), and thermoplastic starch (TPS).

6. The composition for biodegradable meltblown nonwoven fabrics according to claim 5, wherein the weight ratio of the PHA resin to the biodegradable resin is 1:99 to 99:

1.

7. The composition for biodegradable meltblown nonwoven fabrics according to claim 5, wherein the weight ratio of the PHA resin to the polylactic acid (PLA) resin is 20:80 to 70:

30.

8. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, further comprising at least one additive selected from the group consisting of pigments, dye absorbers, light absorbers, antioxidants, compatibilizers, bulking agents, nucleating agents, melt strength agents, slip agents, and fluidizing agents.

9. 2. The biodegradable meltblown nonwoven fabric composition of claim 1, wherein the PHA resin further comprises at least one repeating unit selected from the group consisting of 3-hydroxybutyric acid (3-HB), 3-hydroxypropionic acid (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV), and 6-hydroxyhexanoate (6-HH).

10. The composition for biodegradable meltblown nonwoven fabrics according to claim 1, wherein the composition for biodegradable meltblown nonwoven fabrics has a melt flow index of 10 g / 10 min to 30 g / 10 min, measured at 190 ° C. and 2.16 kg in accordance with ASTM D1238, and a weight average molecular weight of 500,000 g / mol or less.

11. A biodegradable meltblown nonwoven fabric comprising biodegradable fibers, the biodegradable fibers comprising a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units, the biodegradable fibers having an average diameter of 10 μm or less and a standard deviation of the average diameter of 1.3 or less.

12. The biodegradable meltblown nonwoven fabric has a filtration efficiency of 8% or more at 0.3 μm and a filtration efficiency of 10% or more at 0.5 μm according to KS K ISO 9073-152007, and a total thickness of 0.05 mm to 20 mm. The biodegradable meltblown nonwoven fabric according to claim 11, wherein the nonwoven fabric has a basis weight of 10 gsm to 500 gsm.

13. The biodegradable meltblown nonwoven fabric has a warp strength of 3N or more and a warp elongation of 6% or more based on a basis weight of 30 gsm in accordance with K ISO 9073-3:1989. The biodegradable meltblown nonwoven fabric according to claim 11.

14. The biodegradable meltblown nonwoven fabric according to claim 11, wherein the biodegradable fiber is a composite fiber having a different cross section, or a composite fiber having two or more or three or more components.

15. The biodegradable meltblown nonwoven fabric of claim 11, further comprising a functional coating layer on at least one side thereof.

16. A method for producing a biodegradable meltblown nonwoven fabric, comprising melt-extruding a composition for a biodegradable meltblown nonwoven fabric or pellets produced therefrom, followed by spinning, The composition for biodegradable meltblown nonwoven fabrics comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyric acid (4-HB) repeating units; A method for producing a biodegradable meltblown nonwoven fabric, the melt flow index (MFI) of which is 30 g / 10 min or more as measured at 210°C and 2.16 kg in accordance with ASTM D1238.

17. The method for producing a biodegradable meltblown nonwoven fabric according to claim 16, wherein the melt extrusion temperature is 150°C to 230°C.

18. The method for producing a biodegradable meltblown nonwoven fabric according to claim 16, wherein the spinning step is carried out so as to adjust the basis weight of the produced biodegradable meltblown nonwoven fabric to 10 gsm to 500 gsm.

19. The method for producing a biodegradable meltblown nonwoven fabric according to claim 16, wherein the step of spinning the composition for the biodegradable meltblown nonwoven fabric is carried out using a sheath-core composite spinning device.

20. The method for producing a biodegradable meltblown nonwoven fabric according to claim 19, wherein the weight ratio of the raw materials supplied to the core and the sheath is 5:95 to 95:

5.

21. The method for producing a biodegradable meltblown nonwoven fabric according to claim 19, wherein the composition for a biodegradable meltblown nonwoven fabric is supplied to a core.

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