Composition for biodegradable melt-blown nonwoven fabric and biodegradable melt-blown nonwoven fabric manufactured using same

Abstract

The present invention relates to a composition for a biodegradable melt-blown nonwoven fabric, and a biodegradable melt-blown nonwoven fabric manufactured using the same. Specifically, according to one embodiment of the present invention, a composition for a biodegradable melt-blown nonwoven fabric comprises a polyhydroxyalkanoate (Pha) resin containing 4-hydroxybutyrate (4-HB) repeating units, and satisfies a melt flow index (MFI) of at least 30 g / 10 min as measured according to ASTM D1238 at 210 DEG C and 2.16 kg, and thus is environmentally friendly, and can be used as a non-woven fabric. According to the present invention, the composite material has excellent biodegradability and biocompatibility, and can enhance the properties, such as filterability, air permeability, flexibility, diameter uniformity, and the like, of fibers manufactured under high temperature and high pressure conditions such as a melt-blowing process.

Description

Technical Field

[0001] The present invention relates to a composition for biodegradable melt-blown nonwoven fabric and the melt-blown nonwoven fabric prepared therefrom. Background Art

[0002] In recent years, as concerns about environmental issues have increased, research on the treatment and recycling of various household wastes is being actively conducted. Specifically, although polymer materials that are cheap and have excellent processability are widely used to manufacture various products such as paper, films, fibers, packaging materials, bottles, and containers, at the end of the life of these products, they may emit harmful substances when they are incinerated and require hundreds of years (depending on their type) to completely decompose naturally.

[0003] Therefore, research continues on biodegradable polymers that can be decomposed in a short time to enhance environmental friendliness while enhancing mechanical properties (such as flexibility and strength), productivity and processability, and increasing the life of the product itself, thereby reducing the amount of waste or enhancing its recyclability.

[0004] Polyhydroxyalkanoates (PHAs) are biodegradable polymers composed of various hydroxycarboxylic acids produced by various microorganisms and used as intracellular storage materials. PHAs have similar physical properties to traditional petroleum-derived synthetic polymers such as polybutylene terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA), and exhibit complete biodegradability and excellent biocompatibility.

[0005] Meanwhile, nonwoven fabrics are an industrial fiber material used in various fields, for example, to control suspended matter such as fine particles or gases in the air, or as a key material in the filtration process to control the purity of water used in industrial sites such as food processing. In particular, since the 2000s, due to increased concern about the harmfulness of yellow dust, fine dust, and ultrafine dust to the human body, and due to the 2019 novel coronavirus, attention has increased on nonwoven fabrics used as filter materials; therefore, research on this is being actively conducted.

[0006] Traditionally, petrochemical-based polymer materials have been used as materials for nonwoven fabrics. However, since petrochemical-based polymer materials are difficult to collect or recycle after use, they are discarded in the soil or ocean, thereby seriously polluting the environment. Although biodegradable polymers that can improve biodegradability are used, their raw materials are expensive or have limitations on improving the filterability, air permeability, flexibility, etc. required for nonwoven fabrics.

[0007] In addition, nonwoven fabrics are mainly manufactured by meltblowing process or spunbond process.Compared with spunbond nonwoven fabrics, meltblown nonwoven fabrics can be manufactured using ultrafine fibers, so they have excellent flexibility, and are easily laminated with other nonwoven fabrics, but because polymer is melt-spun under high temperature and high pressure conditions, the diameter uniformity of the produced fiber is poor.Therefore, it is necessary to develop a kind of biodegradable nonwoven fabric, this nonwoven fabric is due to its excellent biodegradability and biocompatibility, accompanied by characteristics such as filterability, air permeability, flexibility and environmentally friendly, and the diameter of the fiber produced under high temperature and high pressure conditions such as meltblown process has excellent uniformity.

[0008] [Prior art literature]

[0009] [Patent Literature]

[0010] (Patent Document 1) Korean Patent Publication No. 2012-0103158 Summary of the invention

[0011] Technical issues

[0012] Therefore, an object of the present invention is to provide a biodegradable nonwoven fabric which is environmentally friendly due to its excellent biodegradability and biocompatibility, along with properties such as filterability, air permeability, flexibility, etc., and has excellent uniformity in the diameter of fibers produced under high temperature and high pressure conditions such as a melt-blowing process.

[0013] Technical Solution

[0014] The composition for a biodegradable melt-blown nonwoven fabric according to an embodiment of the present invention includes a polyhydroxyalkanoate (PHA) resin containing a 4-hydroxybutyrate (4-HB) repeating unit, wherein the melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 is 30 g / 10 min or more.

[0015] According to one embodiment of the present invention, the PHA resin may include a 4-hydroxybutyrate (4-HB) repeating unit in an amount of 0.1 wt % to 60 wt %.

[0016] According to one embodiment of the present invention, the PHA resin may include a first PHA resin.

[0017] According to one embodiment of the present invention, the first PHA resin may include 4-hydroxybutyrate (4-HB) repeating units in an amount of 15 wt % to 60 wt %, and may 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 according to ASTM D1238.

[0018] According to one embodiment of the present invention, the PHA resin may include a second PHA resin.

[0019] According to one embodiment of the present invention, the second PHA resin may include 4-hydroxybutyrate (4-HB) repeating units in an amount of 0.1 wt % to 30 wt %, and may have a melt flow index of 0.1 to 15 g / 10 min when measured at 165° C. and 5 kg according to ASTM D1238.

[0020] According to one embodiment of the present invention, the composition for biodegradable melt-blown nonwoven fabrics may include 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).

[0021] 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.

[0022] 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.

[0023] According to one 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, weighting agents, nucleating agents, melt strength agents, slip agents and fluidizers.

[0024] According to one embodiment of the present invention, the PHA resin may further include at least one repeating unit selected from the group consisting of 3-hydroxybutyrate (3-HB), 3-hydroxypropionate (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV) and 6-hydroxyhexanoate (6-HH).

[0025] According to one embodiment of the present invention, the composition for a biodegradable meltblown nonwoven fabric may have a melt flow index of 10 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.

[0026] A biodegradable melt-blown nonwoven fabric according to another embodiment of the present invention comprises biodegradable fibers, wherein the biodegradable fibers comprise a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and the average diameter of the biodegradable fibers is 10 μm or less, and the standard deviation of the average diameter is 1.3 or less.

[0027] According to another embodiment of the present invention, 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 according to KS K ISO 9073-15 2007, a total thickness of 0.05 to 20 mm, and a basis weight of 10 to 500 gsm.

[0028] 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 based on a basis weight of 30 gsm according to K ISO 9073-3:1989.

[0029] According to another embodiment of the present invention, the biodegradable fiber may be a composite fiber of heterogeneous cross-section or a composite fiber of two or more or three or more components.

[0030] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further include a functional coating on at least one side thereof.

[0031] According to another embodiment of the present invention, a method for preparing a biodegradable melt-blown nonwoven fabric comprises: melt-extruding a composition for a biodegradable melt-blown nonwoven fabric or pellets prepared therefrom, and then spinning the same, wherein the composition for the biodegradable melt-blown nonwoven fabric comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and has a melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 of 30 g / 10 min or more.

[0032] According to another embodiment of the present invention, the melt extrusion temperature may be 150°C to 230°C.

[0033] According to another embodiment of the present invention, the spinning step may be performed such that the basis weight of the biodegradable melt-blown nonwoven fabric prepared thereby is adjusted to 10 gsm to 500 gsm.

[0034] According to another embodiment of the present invention, the step of spinning the composition for a biodegradable melt-blown nonwoven fabric may be performed using a sheath-core composite spinning device.

[0035] According to another embodiment of the present invention, the weight ratio of the raw materials to be fed to the core part and the sheath part may be 5:95 to 95:5.

[0036] According to another embodiment of the present invention, the composition for the biodegradable melt-blown nonwoven fabric may be fed into the core part.

[0037] Effects of the Invention

[0038] The composition for a biodegradable melt-blown nonwoven fabric according to one embodiment of the present invention comprises a polyhydroxyalkanoate (PHA) resin containing a 4-hydroxybutyrate (4-HB) repeating unit, wherein the melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 is controlled to be 30 g / 10 min or higher. Therefore, due to its excellent biodegradability and biocompatibility, it is environmentally friendly along with properties such as filterability, air permeability, flexibility, and the like, and can improve the uniformity of the diameter of the fiber produced under high temperature and high pressure conditions such as a melt-blown process.

[0039] In addition, not only can the biodegradable melt-blown nonwoven fabric be directly prepared from the composition for biodegradable melt-blown nonwoven fabric, but also the biodegradable granules obtained from the composition for biodegradable melt-blown nonwoven fabric can be used to prepare the biodegradable melt-blown nonwoven fabric, which provides a convenient option for selecting a process according to needs.

[0040] Furthermore, since the composition for a biodegradable melt-blown nonwoven fabric and the biodegradable melt-blown nonwoven fabric prepared therefrom are biodegradable in soil and ocean and have excellent thermal and mechanical properties, they can be advantageously applied to more diverse fields to exhibit excellent characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a scanning electron microscope (SEM, 100 times magnification) image of the biodegradable melt-blown nonwoven fabric of Example 14.

[0042] Figure 2 is a scanning electron microscope (SEM, 1,000 times magnification) image of the biodegradable melt-blown nonwoven fabric of Example 14. DETAILED DESCRIPTION

[0043] Best Mode for Carrying Out the Invention

[0044] The present invention is described in detail below. The present invention is not limited to the contents disclosed below, and can be modified into various forms as long as the gist of the present invention is not changed.

[0045] In the present specification, when it is mentioned that a part “comprises” a certain element, unless explicitly stated otherwise, it should be understood that other elements may be included rather than excluded.

[0046] Unless otherwise indicated, all numbers and expressions relating to quantities of ingredients, reaction conditions, and so forth used herein are to be understood as being modified by the term "about."

[0047] In this specification, the terms first, second, etc. are used to describe various components. However, the components should not be limited by these terms. These terms are only used to distinguish one component from another component.

[0048] Composition for biodegradable meltblown nonwoven fabrics

[0049] The composition for a biodegradable melt-blown nonwoven fabric according to one embodiment of the present invention includes a polyhydroxyalkanoate (PHA) resin containing a 4-hydroxybutyrate (4-HB) repeating unit, wherein the melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 is 30 g / 10 min or more.

[0050] Nonwoven fabrics are fiber aggregates or films that are bonded to each other using physical or chemical methods rather than by spinning, weaving or knitting. It is directly made into the form of fabric by utilizing the fusion force of the fiber itself or the entanglement of the fiber. Traditionally, nonwoven fabrics are made using petrochemical-based materials such as polypropylene (PP), but their biodegradability is low. Therefore, a method of using polylactic acid (PLA) as a nonwoven fabric material has been proposed. However, the degree of improvement in biodegradability is not great. Due to its low flexibility, it feels rough and stiff, and is difficult to apply to various fields due to poor availability or wearing comfort.

[0051] In addition, nonwoven fabrics are mainly manufactured by meltblown process or spunbond process. Compared with spunbond nonwoven fabrics, meltblown nonwoven fabrics can be manufactured using ultrafine fibers, so they have excellent flexibility and are easy to laminate with other nonwoven fabrics, but because the polymer is melt-spun under high temperature and high pressure conditions, the diameter uniformity of the produced fibers is poor.

[0052] However, the composition for biodegradable melt-blown nonwoven fabrics according to one embodiment of the present invention comprises a polyhydroxyalkanoate (PHA) resin containing a 4-hydroxybutyrate (4-HB) repeating unit, wherein the melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 is controlled to be 30 g / 10 min or higher. Therefore, due to its excellent biodegradability and biocompatibility, it is environmentally friendly along with properties such as filterability, air permeability, flexibility, and the like, and can improve the uniformity of the diameter of the fiber produced under high temperature and high pressure conditions such as the melt-blown process.

[0053] A composition for a biodegradable melt-blown nonwoven fabric according to one embodiment of the present invention includes a polyhydroxyalkanoate resin including a 4-hydroxybutyrate (4-HB) repeating unit.

[0054] Specifically, the composition for a biodegradable melt-blown nonwoven fabric according to one embodiment of the present invention includes a polyhydroxyalkanoate (PHA) resin, which is a copolymerized polyhydroxyalkanoate resin containing a 4-hydroxybutyrate (4-HB) repeating unit, specifically, a specific first PHA resin and / or a specific second PHA resin having a 4-HB repeating unit, thereby being environmentally friendly due to excellent biodegradability and biocompatibility, and a biodegradable melt-blown nonwoven fabric having excellent properties can be easily prepared.

[0055] Furthermore, since the composition for a biodegradable melt-blown nonwoven fabric and the biodegradable melt-blown nonwoven fabric prepared therefrom are biodegradable in soil and ocean and have excellent thermal and mechanical properties, they can be advantageously applied to more diverse fields to exhibit excellent characteristics.

[0056] PHA is a natural thermoplastic polyester polymer that accumulates in microbial cells. Since it is a biodegradable material, it can be composted and eventually decomposed into carbon dioxide, water, and organic waste without generating toxic waste. In particular, since PHA is biodegradable even in soil and ocean, when the composition for biodegradable melt-blown nonwoven fabrics and the biodegradable melt-blown nonwoven fabrics prepared using the same contain PHA resins, it can have environmentally friendly properties. Therefore, the composition for biodegradable melt-blown nonwoven fabrics and the biodegradable melt-blown nonwoven fabrics prepared using the same have a great advantage in that they can be used in various fields because they are biodegradable and environmentally friendly.

[0057] Specifically, PHA is a natural thermoplastic polyester polymer that accumulates in microbial cells. When certain bacteria are disproportionately supplied with nutrients (nitrogen source, phosphorus, etc.), it accumulates PHA in the cells to store carbon and energy.

[0058] In addition, PHA has similar physical properties to traditional petroleum-derived synthetic polymers such as polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene succinate terephthalate (PBST), and polybutylene succinate adipate (PBSA), and exhibits complete biodegradability and excellent biocompatibility.

[0059] In particular, unlike other environmentally friendly plastic materials such as PBS, PLA, and PTT, PHA can be synthesized from more than 150 types of monomers, so hundreds of types of PHA can be prepared according to the monomer types. The hundreds of different types of PHA according to the monomer types have completely different structures and properties.

[0060] PHA resins can be composed of a single monomer repeating unit in living cells and can be formed by polymerizing one or more monomer repeating units. Specifically, PHA resins can be homopolymerized polyhydroxyalkanoate resins (hereinafter referred to as HOMOPHA resins) or copolymerized polyhydroxyalkanoate resins (hereinafter referred to as copolymerized PHA resins), i.e., copolymers in which different repeating units are randomly distributed in the polymer chain.

[0061] Examples of repeating units that may be contained in the PHA resin include 2-hydroxybutyrate, lactic acid, glycolic acid, 3-hydroxybutyrate (hereinafter referred to as 3-HB), 3-hydroxypropionate (hereinafter referred to as 3-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-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 one or more repeating units selected from the above.

[0062] Specifically, the PHA resin may include 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.

[0063] That is, the PHA resin may be a HOMO PHA resin composed only of 4-HB repeating units, or a copolymer PHA resin containing 4-HB repeating units.

[0064] In addition, the PHA resin may be a copolymerized PHA resin comprising a 4-HB repeating unit and further comprising one repeating unit different from the 4-HB repeating unit, or two, three, four, five, six or more repeating units different from each other. For example, the PHA resin may be poly-3-hydroxybutyrate-co-4-hydroxybutyrate (hereinafter referred to as 3HB-co-4HB).

[0065] In addition, 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.

[0066] In addition, the PHA resin may be a copolymerized PHA resin having controlled crystallinity. For example, the PHA resin may contain at least one or more 4-HB repeating units, and the content of the 4-HB repeating units may be controlled to adjust the crystallinity of the PHA resin.

[0067] For example, the PHA resin may be a copolymerized PHA resin comprising at least one repeating unit selected from the group consisting of 3-hydroxybutyrate (3-HB), 4-hydroxybutyrate (4-HB), 3-hydroxypropionate (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV) and 6-hydroxyhexanoate (6-HH).

[0068] Specifically, the copolymerized PHA resin may include 4-HB repeating units and further include 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 include 4-HB repeating units and 3-HB repeating units.

[0069] More specifically, the PHA resin may include 4-HB repeating units in an amount of 0.1 wt % to 60 wt %. For example, the PHA resin may be a copolymerized PHA resin including 4-HB repeating units and 3-HB repeating units, and may include 4-HB repeating units in an amount of 0.1 wt % to 60 wt %.

[0070] The PHA resin can contain 4-HB repeating units in an amount of 0.5 wt % to 50 wt %, 1 wt % to 45 wt %, 5 wt % to 45 wt %, 8 wt % to 40 wt %, 10 wt % to 38 wt %, 15 wt % to 35 wt %, or 20 wt % to 30 wt %.

[0071] In addition, the PHA resin may be a copolymerized PHA resin comprising a 4-HB repeating unit and a 3-HB repeating unit, and may contain 20 wt % or more of the 3-HB repeating unit. For example, the PHA resin may contain 35 wt % or more, 40 wt % or more, 50 wt % or more, 60 wt % or more, 70 wt % or more, or 75 wt % or more, and may contain 99 wt % or less, 98 wt % or less, 97 wt % or less, 96 wt % or less, 95 wt % or less, 93 wt % or less, 91 wt % or less, 90 wt % or less, 80 wt % or less, 70 wt % or less, 60 wt % or less, or 55 wt % or less of the 3-HB repeating unit.

[0072] The crystallinity-adjusted PHA resin may be a PHA resin in which its crystallinity and amorphousness are adjusted as irregularities in its molecular structure increase. Specifically, the type or ratio of monomers or the type or content of isomers may be adjusted.

[0073] According to one embodiment of the present invention, the PHA resin may include two or more types of PHA resins having different crystallinity. Specifically, the PHA resin may be prepared by mixing two or more types of PHA resins having different crystallinity to have a 4-HB repeating unit content within a specific range.

[0074] Specifically, the PHA resin may include a first PHA that is an amorphous PHA resin having controlled crystallinity.

[0075] As an amorphous PHA resin with controlled crystallinity (hereinafter referred to as an aPHA resin), the first PHA resin may include 4-HB repeating units in an amount of 15 wt % to 60 wt %, 15 wt % to 55 wt %, 20 wt % to 55 wt %, 25 wt % to 55 wt %, 30 wt % to 55 wt %, 35 wt % to 55 wt %, 20 wt % to 50 wt %, 25 wt % to 50 wt %, 30 wt % to 50 wt %, 35 wt % to 50 wt %, or 20 wt % to 40 wt %.

[0076] 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. In addition, 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 not be measured, or may be 100°C to 170°C, 100°C to 160°C, 110°C to 160°C, or 120°C to 150°C.

[0077] In the present specification, glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) can be measured using a differential scanning calorimeter (DSC). Specifically, glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) can be measured by performing a first scan or a second scan in a differential scanning calorimetry (DSC) mode, and they can be confirmed from a heat flow curve obtained by these scans. More specifically, glass transition temperature (Tg), crystallization temperature (Tc) and melting temperature (Tm) can be determined from a heat flow curve, which is obtained by increasing the temperature from 40°C to 180°C at a rate of 10°C / min, and then cooling the temperature to -50°C at a rate of 10°C / min.

[0078] The first PHA resin may have a melt flow index (MFI) of 0.1 to 20 g / 10 min, measured at 165° C. and 5 kg according to ASTM D1238. For example, the melt flow index (MFI) of the first PHA resin measured at 165° C. and 5 kg according to ASTM D1238 can 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.

[0079] The first PHA resin may have a weight average molecular weight of 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.

[0080] Furthermore, the PHA resin may include a second PHA resin that is a semi-crystalline PHA resin.

[0081] As a semi-crystalline PHA resin with controlled crystallinity (hereinafter referred to as scPHA resin), the second PHA resin may include 4-HB repeating units in an amount of 0.1 wt % to 30 wt %. For example, the second PHA resin may include 4-HB repeating units in an amount of 0.1 wt % to 30 wt %, 0.5 wt % to 30 wt %, 1 wt % to 29 wt %, 3 wt % to 29 wt %, 1 wt % to 28 wt %, 1.5 wt % to 25 wt %, 2 wt % to 20 wt %, 2.5 wt % to 15 wt %, 3 wt % to 25 wt %, 5 wt % to 21 wt %, 6 wt % to 18 wt %, 10 wt % to 30 wt %, 10 wt % to 20 wt %, 13 wt % to 23 wt %, or 15 wt % to 20 wt %.

[0082] 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.

[0083] In addition, the second PHA resin may have a melt flow index measured at 165° C. and 5 kg according to ASTM D1238 of about 0.1 g / 10 min to about 15 g / 10 min. For example, the melt flow index (MFI) of the second PHA resin measured at 165° C. and 5 kg according to ASTM D1238 can 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.

[0084] The second PHA resin may have a weight average molecular weight of 10,000 to 1,200,000 g / mole, 50,000 to 1,100,000 g / mole, 50,000 to 350,000 g / mole, 100,000 to 1,000,000 g / mole, 100,000 to 900,000 g / mole, 200,000 to 800,000 g / mole, 200,000 to 600,000 g / mole, 200,000 to 500,000 g / mole, or 500,000 to 1,200,000 g / mole.

[0085] The first PHA resin and the second PHA resin may be distinguished according to the content of the 4-HB repeating unit, and may have at least one property selected from the group consisting of a glass transition temperature (Tg), a crystallization temperature (Tc), a melting temperature (Tm), and a melt flow index. Specifically, the first PHA resin and the second PHA resin may be distinguished according to the content of the 4-HB repeating unit, the glass transition temperature (Tg), the crystallization temperature (Tg), the melting temperature (Tm), the melt flow index, etc. For example, the content of the 4-HB repeating unit of the first PHA resin and the content of the 4-HB repeating unit of the second PHA resin may be different from each other.

[0086] According to one embodiment of the present invention, the PHA resin may include the first PHA resin or the second PHA resin, or it may include both the first PHA resin and the second PHA resin.

[0087] Specifically, since the PHA resin includes a first PHA resin (which is an amorphous PHA resin) or 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, since the contents of the first PHA resin and the second PHA resin are adjusted, desired physical properties can be more effectively controlled.

[0088] According to one embodiment of the present invention, the PHA resin may include the first PHA resin or the second PHA resin. Specifically, the PHA resin may consist of only the first PHA resin or only the second PHA resin.

[0089] 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 to 5. For example, the weight ratio of the first PHA resin to the second PHA resin may be 1:0.5 to 4.5, 1:0.6 to 4.2, or 1:0.7 to 3.5. When the weight ratio of the first PHA resin to the second PHA resin satisfies the above range, the desired physical properties can be more effectively controlled.

[0090] In addition, 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.

[0091] In addition, 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.

[0092] The melting temperature (Tm) of the PHA resin may not be measured, or 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.

[0093] The decomposition temperature (Td, weight loss 5%) of the PHA resin may be 220 to 280°C, 245 to 275°C, 255 to 270°C, or 260 to 270°C, as measured by a thermogravimetric analyzer (TGA).

[0094] In the present specification, the decomposition temperature (Td) may be measured using a thermogravimetric analyzer (TGA). Specifically, the decomposition temperature (Td) may be determined as a temperature at which the weight of the PHA resin decreases by 5% according to a weight change curve obtained by increasing the temperature from room temperature to 600°C at a rate of 10°C / min using a thermogravimetric analyzer (TGA).

[0095] In addition, the weight average molecular weight of the PHA resin may be 10,000 g / mol to 1,200,000 g / mol. For example, the weight average molecular weight of the PHA resin 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 800,000 g / mol, 250,000 g / mol to 1,150,000 g / mol, In some embodiments, the present invention relates to an aqueous solution of at least one iodine number, such as 0.05 g / mol, 0.1 g / mol, 0.2 g / mol, 0.3 g / mol, 0.4 g / mol, 0.5 g / mol, 0.6 g / mol, 0.7 g / mol, 0.8 g / mol, 0.9 g / mol, 1.1 g / mol, 1.2 g / mol, 1.3 g / mol, 1.4 g / mol, 1.5 g / mol, 1.6 g / mol, 1.7 g / mol, 1.8 g / mol, 1.9 g / mol, 2.0 g / mol, 1.1 g / mol, 1.2 g / mol, 1.4 g / mol, 1.5 g / mol, 1.6 g / mol, 1.7 g / mol, 1.8 g / mol, 1.9 g / mol, 2.0 g / mol, 1.2 g / mol, 1.4 g / mol, 1.5 g / mol,

[0096] The crystallinity of the PHA resin may be 90% or less, as measured by differential scanning calorimetry (DSC). For example, the crystallinity of the PHA resin may be measured by differential scanning calorimetry and may be 90% or less, 85% or less, 80% or less, 75% or less, or 70% or less.

[0097] In addition, the average particle size of the PHA resin may be 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.

[0098] 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 Zetasizer Nano ZS (manufacturer: Marven) at a temperature of 25°C and a measurement angle of 175°. In this case, the value of the peak obtained by the polydispersity index (PDI) within a confidence interval of 0.5 is used as the particle size.

[0099] The polydispersity index (PDI) of the PHA resin may be less than 2.5. For example, the polydispersity index of the PHA resin may be 2.4 or less, 2.3 or less, 2.1 or less, or 2.0 or less.

[0100] In addition, PHA resin can be obtained by cell disruption using non-mechanical methods or chemical methods. Specifically, since PHA resin is a natural thermoplastic polyester polymer accumulated in microbial cells and has a relatively large average particle size, it can be obtained through a disruption process to more effectively control the yield or physical properties of the desired material and improve process efficiency.

[0101] Meanwhile, according to another embodiment of the present invention, the composition for biodegradable melt-blown nonwoven fabric may include 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).

[0102] Since the biodegradable resin is used together with the PHA resin, the composition for the biodegradable melt-blown nonwoven fabric has excellent dispersibility, and the filtration efficiency as well as the filterability, air permeability and flexibility required for the nonwoven fabric can be further improved.

[0103] The composition for biodegradable melt-blown nonwoven fabric can include 15 % by weight or more of PHA resin based on the gross weight of the composition for biodegradable melt-blown nonwoven fabric. For example, the content of PHA resin can 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, 100 % by weight based on the gross weight of the composition for biodegradable melt-blown nonwoven fabric.

[0104] In addition, the composition for biodegradable melt-blown nonwoven fabric can include a biodegradable resin of an amount less than 90 wt % based on the gross weight of the composition for biodegradable melt-blown nonwoven fabric. For example, the content of biodegradable resin can be 85 wt % or less, 80 wt % or less, 70 wt % or less, 60 wt % or less, 45 wt % or less or 35 wt % or less. Specifically, the content of biodegradable resin can be 35 wt % to 80 wt %, but is not limited thereto.

[0105] According to another embodiment of the present invention, the weight ratio of the PHA resin to the biodegradable resin may be 1:99 to 99:1. For example, the weight ratio of the PHA resin to the 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. Since the weight ratio of the PHA resin to the biodegradable resin satisfies the above range, while the biodegradability and processability are not deteriorated, the uniformity of the diameter of the fiber produced under high temperature and high pressure conditions such as the melt-blown process, as well as properties such as filterability, air permeability, flexibility, etc. can be improved.

[0106] Specifically, the biodegradable resin may be polylactic acid (PLA). More specifically, the weight ratio of the PHA resin to the PLA resin may be 10:90 to 70:30. For example, the weight ratio of the PHA resin to the 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. Since the weight ratio of the PHA to the PLA resin satisfies the above range, while the biodegradability and processability are not deteriorated, the uniformity of the diameter of the fiber produced under high temperature and high pressure conditions such as the melt-blown process, as well as properties such as filterability, air permeability, flexibility, etc., can be further improved.

[0107] According to another embodiment of the present invention, the composition for biodegradable melt-blown nonwoven fabrics may further comprise at least one additive selected from the group consisting of pigments, dye absorbers, light absorbers, antioxidants, compatibilizers, weighting agents, nucleating agents, melt strength agents, slip agents, and fluidizing agents.

[0108] 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 metals such as Cu, metal oxides, metalloid oxides, or combinations thereof, but are not limited thereto.

[0109] The pigment can be further used in an amount of 0.01 wt % to 20 wt %, 0.01 wt % to 15 wt %, 0.01 wt % to 12 wt %, 0.01 wt % to 10 wt %, 0.01 wt % to 8 wt %, 0.01 wt % to 5 wt %, 0.2 wt % to 4.5 wt %, 0.2 wt % to 4 wt %, or 0.5 wt % to 3 wt %, based on the total weight of the composition for the biodegradable melt-blown nonwoven fabric.

[0110] The antioxidant is an additive for preventing decomposition by ozone or oxygen, preventing oxidation during storage, or preventing deterioration of physical properties. As long as the effects of the present invention are not impaired, a general antioxidant can be used.

[0111] Specifically, the antioxidant may include at least one selected from the group consisting of a hindered phenol-based antioxidant and a phosphite-based (phosphorus-based) antioxidant.

[0112] The hindered phenol-based antioxidant may include, for example, at least one selected from the group consisting of 4,4′-methylene-bis(2,6-di-tert-butylphenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, pentaerythritol tetrakis[3-(3,5-di-tert-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.

[0113] The phosphite-based (phosphorus-based) antioxidant may include, for example, at least one selected from the group consisting of tris(2,4-di-tert-butylphenyl)phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, distearylpentaerythritol diphosphite, [bis(2,4-di-tert-butyl-5-methylphenoxy)phosphino]biphenyl, and N,N-bis[2-[[2,4,8,10-tetrakis(1,1-dimethylethyl)dibenzo[d,f][1,3,2]dioxaphosphocycloheptan-6-yl]oxy]-ethyl]ethylamine.

[0114] Antioxidant can further be used with the 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 gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of antioxidant meets above-mentioned scope, the physical property of nonwoven fabric can be enhanced, and can be more conducive to realizing the expected effect of the present invention.

[0115] The compatibilizer is an additive that imparts compatibility by removing the mold release property of the biodegradable resin and / or the PHA resin. A general compatibilizer can be used as long as the effects of the present invention are not impaired.

[0116] 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 glyceryl stearate.

[0117] Compatibilizer can further be used with the 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 gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of compatibilizer meets above-mentioned scope, physical property can be enhanced by improving the compatibility between resins used, and can be more conducive to realizing the expected effect of the present invention.

[0118] The weighting agent is an inorganic material and an additive for improving moldability by increasing the crystallization rate during molding and for reducing the cost increase problem caused by using a resin having higher biodegradability than a synthetic resin. General inorganic materials can be used as long as the effects of the present invention are not impaired.

[0119] The weighting agent may include 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.

[0120] The average particle size of the weighting agent may be 0.5 μm to 5 μm. For example, the average particle size of the weighting 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 weighting agent is less than 0.5 μm, the particles are difficult to disperse. If it exceeds 5 μm, the size of the particles becomes too large, which may impair the effect of the present invention.

[0121] The weighting agent can further be used 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 gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of weighting agent meets above-mentioned scope, it can be more conducive to realizing the expected effect of the present invention.

[0122] A nucleating agent is an additive used to supplement or change the crystal morphology of a polymer and to increase the crystallization (solidification) rate when the polymer melt is cooled. In particular, since the PHA resin used in the present invention has a low crystallization rate, processing may not be easy to carry out due to insufficient crystallization during processing. If a nucleating agent is used to solve this problem, the crystallization rate can be increased, further improving processability, moldability and productivity, and the desired physical properties can be effectively achieved.

[0123] As long as the effect of the present invention is not impaired, general nucleating agents can be used. Specifically, the nucleating agent can include, for example, a metal compound containing a single element substance (pure substance) or a composite oxide, a low molecular weight organic compound with a metal carboxylate group, a polymeric organic compound with a metal carboxylate group, a polymeric organic compound, phosphoric acid or phosphorous acid or its metal salt, a sorbitol derivative, thioglycolic anhydride and p-toluenesulfonic acid or its metal salt, etc. The nucleating agent can be used alone or in combination.

[0124] The metal compound comprising a single element substance (pure substance) or a composite oxide may be at least one selected from the group consisting of, for example, carbon black, calcium carbonate, synthetic silicic acid and its salts, silicon dioxide, zinc white, clay, kaolin, basic magnesium carbonate, mica, talc, quartz powder, diatomaceous earth, dolomite powder, titanium oxide, zinc oxide, antimony oxide, barium sulfate, calcium sulfate, aluminum oxide, calcium silicate, and metal salts of organic phosphorus and boron nitride.

[0125] The low molecular weight organic compound having a metal carboxylate group may be at least one selected from the group consisting of, for example, metal salts of octanoic acid, toluic acid, heptanoic acid, nonanoic 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, monomethyl terephthalate, isophthalic acid, and monomethyl isophthalate.

[0126] The polymeric organic compound having a metal carboxylate group may be at least one selected from the group consisting of, for example, the following metal salts: carboxyl-containing polyethylene obtained by oxidation of polyethylene, carboxyl-containing polypropylene obtained by oxidation of polypropylene, copolymers of acrylic acid or methacrylic acid with olefins (such as ethylene, propylene and 1-butene), copolymers of acrylic acid or methacrylic acid with styrene, copolymers of olefins and maleic anhydride, and copolymers of styrene and maleic anhydride.

[0127] The polymeric organic compound may be at least one selected from the group consisting of, for example, α-olefins branched at the 3-carbon atom and having 5 or more carbon atoms (such as 3,3-dimethylbutene-1,3-methylbutene-1,3-methylpentene-1,3-methylhexene-1 and 3,5,5-trimethylhexene-1), polymers of vinylcycloalkanes (such as vinylcyclopentane, vinylcyclohexane and vinylnorbornane), polyalkylene glycols (such as polyethylene glycol and polypropylene glycol), poly(glycolic acid), cellulose, cellulose esters and cellulose ethers.

[0128] Phosphoric acid or phosphorous acid or its metal salt can be at least one selected from the group consisting of, for example, diphenyl phosphate, diphenyl phosphite, bis(4-tert-butylphenyl)phosphate and methylenebis(2,4-tert-butylphenyl)phosphate. The sorbitol derivative can be, for example, bis(p-methylbenzylidene)sorbitol or bis(p-ethylbenzylidene)sorbitol.

[0129] Nucleating agent can further be used 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 gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of nucleating agent meets the above range, crystallization rate can be improved to enhance processability, and productivity and formability can be further improved by improving crystallization rate in the cutting step process of production pellets in the preparation process, for example.

[0130] The melt strength agent is an additive for improving the melt strength of the reactants. As long as the effects of the present invention are not impaired, a general melt strength agent can be used.

[0131] Specifically, the melt strength agent may include at least one selected from the group consisting of polyester, styrene-based polymers such as acrylonitrile butadiene styrene and polystyrene, polysiloxane, organic modified siloxane polymers, and maleic anhydride grafted ethylene propylene diene monomer (MAH-g-EPDM).

[0132] The melt strength agent can be further used in an amount of 0.01 wt % to 20 wt %, 0.01 wt % to 15 wt %, 0.01 wt % to 12 wt %, 0.01 wt % to 10 wt %, 0.01 wt % to 8 wt %, 0.01 wt % to 5 wt %, 0.2 wt % to 4.5 wt %, 0.2 wt % to 4 wt %, or 0.5 wt % to 3 wt %, based on the total weight of the composition for the biodegradable melt-blown nonwoven fabric. Since the content of the melt strength agent satisfies the above range, it can be more conducive to achieving the expected effects of the present invention.

[0133] The slip agent is an additive for enhancing the slipperiness (slipperiness) during extrusion and for preventing the fiber surfaces from sticking to each other. Specifically, a general slip agent can be used as long as the effect of the present invention is not impaired. For example, the slip agent can be at least one selected from the group consisting of erucic acid amide, oleamide and stearic acid amide.

[0134] Slip agent can further be used in an amount of 0.01 wt % to 20 wt %, 0.01 wt % to 15 wt %, 0.01 wt % to 12 wt %, 0.01 wt % to 10 wt %, 0.01 wt % to 8 wt %, 0.01 wt % to 5 wt %, 0.2 wt % to 4.5 wt %, 0.2 wt % to 4 wt % or 0.5 wt % to 3 wt % based on the gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of slip agent meets the above range, processability, productivity and formability can be further improved, and it can be more conducive to achieving the desired effect of the present invention.

[0135] The composition for the biodegradable melt-blown nonwoven fabric may include a cross-linking agent and / or a stabilizer as additional additives.

[0136] The crosslinking agent is an additive used to change the properties of the PHA resin and increase the molecular weight of the resin. As long as the effects of the present invention are not impaired, a general crosslinking agent can be used.

[0137] For example, the crosslinking agent may be at least one selected from the group consisting of fatty acid esters, natural oils containing epoxy groups (epoxidation), diallyl phthalate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, diethylene glycol dimethacrylate, and bis(2-methacryloyloxyethyl)phosphate.

[0138] The crosslinking agent can be further used in an amount of 0.01 wt % to 20 wt %, 0.01 wt % to 15 wt %, 0.01 wt % to 12 wt %, 0.01 wt % to 10 wt %, 0.01 wt % to 8 wt %, 0.01 wt % to 5 wt %, 0.2 wt % to 4.5 wt %, 0.2 wt % to 4 wt %, or 0.5 wt % to 3 wt %, based on the total weight of the composition for the biodegradable melt-blown nonwoven fabric.

[0139] The stabilizer may be at least one selected from the group consisting of trimethyl phosphate, triphenyl phosphate, trimethyl phosphine, phosphoric acid, and phosphorous acid.

[0140] The stabilizer can be further used in an amount of 0.01 wt % to 20 wt %, 0.01 wt % to 15 wt %, 0.01 wt % to 12 wt %, 0.01 wt % to 10 wt %, 0.01 wt % to 8 wt %, 0.01 wt % to 5 wt %, 0.2 wt % to 4.5 wt %, 0.2 wt % to 4 wt %, or 0.5 wt % to 3 wt %, based on the total weight of the composition for the biodegradable melt-blown nonwoven fabric.

[0141] In the present specification, the additives may be in the form of a monomer, a polymer, or a copolymer, but they are not limited thereto.

[0142] According to another embodiment of the present invention, the composition for the biodegradable melt-blown nonwoven fabric may further include biomass.

[0143] Since the composition for biodegradable melt-blown nonwoven fabrics contains biomass, biodegradability can be improved and soil can be improved. That is, biomass has excellent biodegradability, is easily destroyed when it is not decomposed, improves fertilizer and increases soil strength, thereby producing a soil improvement effect.

[0144] Biomass can be used in an amount of 5 to 50 weight % based on the gross weight of the composition for biodegradable meltblown nonwoven fabric. Specifically, the content of biomass can be 10 weight % to 48 weight %, 15 weight % to 48 weight %, 20 weight % to 45 weight %, 20 weight % to 43 weight % or 20 weight % to 40 weight % based on the gross weight of the composition for biodegradable meltblown nonwoven fabric. Because the content of biomass meets the above range, biodegradability is further enhanced, produces soil improvement effect, and improves with the cross-linking strength of PHA resin, so that the expected effect of the present invention can be effectively achieved.

[0145] The composition for biodegradable meltblown nonwoven fabrics may have a melt flow index of 10 to 30 g / 10 min, measured at 190°C and 2.16 kg according to ASTM D1238. For example, the melt flow index of the composition for biodegradable meltblown nonwoven fabrics measured at 190°C and 2.16 kg according to ASTM D1238 may be 10 to 25 g / 10 min, 11 to 20 g / 10 min, or 12 to 18 g / 10 min.

[0146] In addition, the melt flow index measured according to ASTM D1238 at 210°C and 2.16kg for the composition of biodegradable meltblown nonwoven fabric can be 30 g / 10 min or higher. For example, the melt flow index measured according to ASTM D1238 at 210°C and 2.16kg for the composition of biodegradable meltblown nonwoven fabric can be 45 g / 10 min or higher, 50 g / 10 min or higher, 53 g / 10 min or higher, 55 g / 10 min or higher, 59 g / 10 min or higher, 65 g / 10 min or higher, 80 g / 10 min or higher, 90 g / 10 min or higher, or 100 g / 10 min or higher.

[0147] Melt flow index measured for composition for biodegradable melt-blown nonwoven fabric according to ASTM D1238 Pellets prepared using the composition for biodegradable melt-blown nonwoven fabric may be measured according to ASTM D1238.

[0148] Specifically, the melt flow index of biodegradable pellets can be measured according to ASTM D1238, and the biodegradable pellets are prepared by feeding the composition for biodegradable melt-blown nonwoven fabrics into a twin-screw extruder, mixing and melt-extruding. More specifically, the screw speed of the twin-screw extruder is set to 200 rpm, the composition for biodegradable melt-blown nonwoven fabrics is mixed, the internal temperature is raised from 50° C. to 170° C., melt-extruded at a pressure of 12 bars and a temperature of 177° C., and an underwater cutter system is used to prepare the biodegradable pellets.

[0149] The weight average molecular weight of the composition for biodegradable meltblown nonwoven fabric can be 500,000 g / mole or lower. For example, the weight average molecular weight of the composition for biodegradable meltblown nonwoven fabric can be 450,000 g / mole or lower, 400,000 g / mole or lower or 350,000 g / mole or lower.

[0150] The weight average molecular weight of the composition for biodegradable meltblown nonwoven fabric can be 500,000 g / mole or lower. For example, the weight average molecular weight of the composition for biodegradable meltblown nonwoven fabric can be 450,000 g / mole or lower, 400,000 g / mole or lower or 350,000 g / mole or lower.

[0151] The glass transition temperature (Tg) of the composition for the biodegradable meltblown nonwoven fabric may be -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, the melting temperature (Tm) may be 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 the crystallization temperature (Tc) may not be measured or may be 50°C to 120°C, 65°C to 100°C, or 75°C to 95°C, as measured by differential scanning calorimetry (DSC).

[0152] In addition, the decomposition temperature (Td, weight loss 5%) of the composition for biodegradable melt-blown nonwoven fabric can be 220°C or higher, 230°C or higher, 240°C or higher, 250°C or higher, or 260°C or higher, 220°C to 300°C, 240°C to 300°C, 250°C to 300°C, or 260°C to 300°C, as measured by a thermogravimetric analyzer (TGA).

[0153] Biodegradable meltblown nonwoven fabrics

[0154] A biodegradable melt-blown nonwoven fabric according to another embodiment of the present invention comprises biodegradable fibers, wherein the biodegradable fibers comprise a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and the average diameter of the biodegradable fibers is 10 μm or less, and the standard deviation of the average diameter is 1.3 or less.

[0155] The biodegradable melt-blown nonwoven fabric may be prepared using the composition for a biodegradable melt-blown nonwoven fabric. The details of the PHA resin are as described above.

[0156] The biodegradable melt-blown nonwoven fabric may have 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 9073-15 2007.

[0157] For example, the filtration efficiency of the biodegradable melt-blown nonwoven fabric at 0.3 μm according to KS K ISO 9073-152007 can be 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.

[0158] In addition, the filtration efficiency of the biodegradable melt-blown nonwoven fabric at 0.5 μm according to KS K ISO 9073-152007 can be 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, 70% or more.

[0159] The total thickness of the biodegradable melt-blown nonwoven fabric can be 0.05 mm to 20 mm. For example, the total thickness of the biodegradable melt-blown nonwoven fabric can 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.

[0160] The basis weight of the biodegradable meltblown nonwoven fabric can be 10gsm to 500gsm. For example, the basis weight of the biodegradable meltblown nonwoven fabric can be 12gsm to 450gsm, 15gsm to 400gsm, 20gsm to 350gsm, 20gsm to 250gsm, or 25gsm to 200gsm.

[0161] In addition, the biodegradable melt-blown nonwoven fabric may have a warp strength of 30 N or more based on a basis weight of 120 gsm according to K ISO 9073-3: 1989, and a warp elongation of 10% or more. For example, the biodegradable melt-blown nonwoven fabric may have a warp strength of 33 N or more, 35 N or more, or 36 N or more based on a basis weight of 120 gsm (thickness: 0.28 mm) according to K ISO 9073-3: 1989, and a warp elongation of 11% or more, 13% or more, 15% or more, 18% or more, or 20% or more.

[0162] The biodegradable melt-blown nonwoven fabric may have a warp strength of 20 N or more based on a basis weight of 60 gsm according to K ISO 9073-3:1989, and a warp elongation of 4% or more. For example, the biodegradable melt-blown nonwoven fabric may have a warp strength of 21 N or more, 23 N or more, or 25 N or more based on a basis weight of 60 gsm (thickness: 0.24 mm) according to K ISO 9073-3:1989, and a warp elongation of 4.5% or more, 6% or more, 7% or more, or 8% or more.

[0163] The biodegradable melt-blown nonwoven fabric may have a warp strength of 3N or more based on a basis weight of 30 gsm according to K ISO 9073-3:1989, and a warp elongation of 6% or more. For example, the biodegradable melt-blown 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 based on 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.

[0164] In addition, the biodegradable melt-blown nonwoven fabric may be an aggregate of biodegradable fibers.

[0165] Specifically, the average diameter of the biodegradable fiber may be 10 μm or less, and the standard deviation of the average diameter may be 1.3 or less. For example, the average diameter of the biodegradable fiber 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.

[0166] Additionally, the biodegradable fiber may 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.

[0167] According to another embodiment of the present invention, the biodegradable fiber may be a composite fiber of heterogeneous cross-section or a composite fiber of two or more or three or more components.

[0168] The heterogeneous cross-section fiber may have a circular, elliptical or polygonal cross-section, but is not limited thereto.

[0169] Furthermore, the biodegradable fiber may be of a sheath-core type including a core portion and a sheath portion, a side-by-side type, an island-in-the-sea type, or a segmented pie type.

[0170] In the sheath-core type, the cross section of the core part and the cross section of the sheath part may be different from each other. For example, the cross section of the core part may be circular, and the cross section of the sheath part may be annular, but they are not limited thereto.

[0171] In addition, the biodegradable fiber can be a two-component composite fiber in which the sheath part and the core part each contain different single-component resins. It can be a three-component composite fiber in which the sheath part contains a single-component resin and the core part contains at least a two-component resin, or the core part contains a single-component resin and the sheath part contains at least a two-component resin. In addition, the biodegradable fiber can be a composite fiber in which the sheath part and the core part each contain at least a two-component resin.

[0172] For example, the core part may include PHA resin, and the skin part may include 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), polyhydroxybutyric acid valerate (PHBV), polycaprolactone (PCL), polybutylene succinate adipate terephthalate (PBSAT), polybutylene succinate succinate (PBEAS), polybutylene succinate (PBES) and thermoplastic starch (TPS).

[0173] The weight ratio of the core part to the sheath part may be 5:95 to 95:5. For example, the weight ratio of the core part to the sheath part may be 5:95 to 85:15, 7:93 to 80:20, 10:90 to 75:25, or 10:90 to 70:30.

[0174] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may be electrostatically treated.

[0175] Electrostatic treatment is a method of enhancing the aggregation ability by applying static electricity to nonwoven fabrics. When nonwoven fabrics are subjected to electrostatic treatment, the fibers constituting the nonwoven fabrics are forcibly charged, and thus the nonwoven fabrics made of fibers with polarized charges can easily collect charged particles.

[0176] The electrostatic treatment process may be performed using corona discharge, plasma charging, friction charging, or water charging by high-pressure water droplets, but is not limited thereto.

[0177] In addition, a charging agent may be used to maximize the electrostatic effect, and the charging agent may be a hindered amine-based charging agent, but is not limited thereto.

[0178] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further include a functional coating on at least one side thereof.

[0179] For example, the functional coating may be a hard coating or an antibacterial coating, and an adhesive layer may be interposed between the functional coating and the biodegradable meltblown nonwoven fabric.

[0180] In addition, at least one side of the biodegradable melt-blown nonwoven fabric can be surface treated using ions or electricity. For example, the surface treatment can be carried out by ion coating, ion collection, electrocoating or voltage coating, but is not limited thereto.

[0181] According to another embodiment of the present invention, the biodegradable meltblown nonwoven fabric may further include a biodegradable spunbonded nonwoven fabric on at least one side thereof.

[0182] In addition, the biodegradable melt-blown nonwoven fabric may further include one or more additives selected from the group consisting of a deodorant, an antibacterial agent, an inorganic filler, and a lubricant.

[0183] The deodorant 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.

[0184] Deodorant can be used in an amount of 0.01 wt % to 20 wt % based on the gross weight of biodegradable melt-blown nonwoven fabric. For example, deodorant can be used in an amount of 0.01 wt % to 20 wt %, 0.05 wt % to 15 wt % or 0.1 wt % to 10 wt % based on the gross weight of biodegradable melt-blown nonwoven fabric.

[0185] The antibacterial agent may be at least one selected from the group consisting of nano-silver, nano-copper, nano-zinc, and zeolite-based antibacterial agents, but is not limited thereto.

[0186] The antimicrobial agent can be used in an amount of 0.01% to 20% by weight based on the gross weight of the biodegradable melt-blown nonwoven fabric. For example, the antimicrobial agent can 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 gross weight of the biodegradable melt-blown nonwoven fabric.

[0187] The inorganic filler may include at least one selected from the group consisting of talc, barium oxide, calcium carbonate, magnesium carbonate, zinc carbonate, zinc oxide, magnesium oxide, aluminum oxide, and silicon dioxide, but is not limited thereto.

[0188] The average particle size of the inorganic filler may be 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.

[0189] Inorganic filler can be used in an amount of 0.01 % by weight to 20 % by weight based on the gross weight of biodegradable melt-blown nonwoven fabric. For example, inorganic filler can be used in an amount of 0.01 % by weight to 20 % by weight, 0.05 % by weight to 15 % by weight or 0.1 % by weight to 10 % by weight based on the gross weight of biodegradable melt-blown nonwoven fabric.

[0190] The lubricant may be a fatty acid ester, in particular, a glycerol fatty acid ester, a sorbitan fatty acid ester, a pyridoxine fatty acid ester, or a mixture of at least one selected therefrom, but is not limited thereto.

[0191] Lubricant can be used in an amount of 0.01 % by weight to 20 % by weight based on the gross weight of biodegradable melt-blown nonwoven fabric. For example, lubricant can be used in an amount of 0.01 % by weight to 20 % by weight, 0.05 % by weight to 15 % by weight or 0.1 % by weight to 10 % by weight based on the gross weight of biodegradable melt-blown nonwoven fabric.

[0192] Method for preparing biodegradable meltblown nonwoven fabric

[0193] According to another embodiment of the present invention, a method for preparing a biodegradable melt-blown nonwoven fabric comprises: melt-extruding a composition for a biodegradable melt-blown nonwoven fabric or pellets prepared therefrom, and then spinning the same, wherein the composition for the biodegradable melt-blown nonwoven fabric comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and has a melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 of 30 g / 10 min or more.

[0194] The details of the composition for the biodegradable melt-blown nonwoven fabric are as described above.

[0195] Specifically, in a method for preparing a biodegradable melt-blown nonwoven fabric according to another embodiment of the present invention, the composition for the biodegradable melt-blown nonwoven fabric can be directly fed into the device and spun, or pellets prepared by melt-extruding the composition for the biodegradable melt-blown nonwoven fabric are fed into the device and spun, thereby preparing the biodegradable melt-blown nonwoven fabric.

[0196] According to another embodiment of the present invention, the composition for biodegradable melt-blown nonwoven fabric can be melt-extruded and melt-spun at 150° C. to 230° C. to prepare biodegradable melt-blown nonwoven fabric. For example, the temperature of melt-extrusion and melt-spinning can be 160° C. to 225° C., 180° C. to 220° C., or 195° C. to 215° C.

[0197] In this case, conventional melt spinning equipment can be used without limitation. For example, a melt-blowing melt spinning equipment based on a single screw extruder can be used, but is not limited thereto.

[0198] In addition, the melt-blown melt spinning device can include a melting part, a nozzle part including a filter, a drafting part and a winding part between a nozzle hole and a winding roller. The melting temperature, the nozzle hole diameter, the nozzle hole length, the ratio of the nozzle hole length to the diameter, the size of the filter in the nozzle, the discharge amount through the nozzle, the length of the drafting part, the spinning speed, the cooling temperature, the winding speed of the melt-blown melt spinning device can be controlled to prepare a biodegradable melt-blown nonwoven fabric with desired physical properties.

[0199] In addition, a spinning step can be carried out so that the basis weight of the biodegradable melt-blown nonwoven fabric prepared is adjusted to 10gsm to 500gsm. For example, a spinning step can be carried out so that the basis weight of the biodegradable melt-blown nonwoven fabric prepared is adjusted to 12gsm to 450gsm, 15gsm to 400gsm, 20gsm to 350gsm, 20gsm to 250gsm, 25gsm to 200gsm, 25gsm to 150gsm, 25gsm to 100gsm or 25gsm to 50gsm.

[0200] According to another embodiment of the present invention, pellets can be melt-spun at 150°C to 230°C to prepare a biodegradable melt-blown nonwoven fabric, and the pellets are prepared by melt-extruding a composition for a biodegradable melt-blown nonwoven fabric at a pressure of 6 bar to 30 bar and a temperature of 150°C to 200°C.

[0201] For example, the composition for biodegradable melt-blown nonwoven fabric can be melt-extruded at a pressure of 7 bar to 28 bar or 8 bar to 26 bar and a temperature of 155° C. to 190° C. or 165° C. to 185° C., cooled to 15° C. or lower, 10° C. or lower, or 6° C. or lower, and cut to prepare pellets. These pellets can be melt-spun at 160° C. to 225° C., 180° C. to 220° C., or 195° C. to 215° C., to prepare biodegradable melt-blown nonwoven fabric.

[0202] Furthermore, before the step of subjecting the pellets to melt spinning, a step of drying the pellets at 40 to 58° C. or 42 to 60° C. for 11 hours or longer or 12 hours or longer may be further performed.

[0203] The drying step may be performed until the resin moisture content of the pellets is 2,000 ppm or less, 1500 ppm or less, 1100 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 performed by hot air drying or dehumidification drying, but is not limited thereto.

[0204] According to another embodiment of the present invention, the step of spinning the composition for biodegradable melt-blown nonwoven fabric can be performed using a composite spinning device. For example, the composite spinning device can be a core-sheath composite spinning device.

[0205] Specifically, the composition for the biodegradable melt-blown nonwoven fabric may be directly fed into a core part or a sheath part of a sheath-core composite spinning device to prepare the composition for the biodegradable melt-blown nonwoven fabric.

[0206] More specifically, the composition for the biodegradable melt-blown nonwoven fabric can be fed into the core part or the sheath part, and the 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 succinate terephthalate (PBES) and thermoplastic starch (TPS) can be fed into the core part or the sheath part.

[0207] For example, the composition for the biodegradable melt-blown nonwoven fabric can be fed into the core part, and the 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 succinate (PBES) and thermoplastic starch (TPS) can be fed into the sheath part.

[0208] In addition, a weight ratio of the raw materials fed to the core part and the sheath part 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.

[0209] Mode for Carrying Out the Invention

[0210] The present invention will be described in more detail below with reference to the following examples. However, the following examples are intended to illustrate the present invention, and the scope of the examples is not limited thereto.

[0211] [Example]

[0212] Preparation of biodegradable meltblown nonwoven fabrics

[0213] Example 1

[0214] 30 wt% of a polyhydroxyalkanoate (PHA) resin (3-HB-co-4-HB, manufacturer: CJ) composed of a first PHA resin (aPHA, 4-hydroxybutyrate (4-HB) content: 33 wt%, weight average molecular weight (Mw): 600,000 g / mol, melt flow index at 165°C and 5 kg according to ASTM D1238: 5.5 g / 10 min) was mixed with 70 wt% of polylactic acid (PLA), and then 1 phr of polyvinyl acetate (PVAc, manufacturer: Wacker) was added thereto to prepare a composition for a biodegradable melt-blown nonwoven fabric. Here, phr (per hundred parts of resin) refers to a unit, i.e., an input amount of a material added per 100 parts by weight of a polymer (1 phr: 1 g input amount when the polymer is 100 g).

[0215] The composition for biodegradable melt-blown nonwoven fabric was melt-extruded and then spun through a nozzle to prepare a biodegradable melt-blown nonwoven fabric (basis weight: 30 gsm), which was then electrostatically treated. In this case, specific process conditions were as follows.

[0216] - Melting and spinning temperature: 210℃

[0217] -Nozzle: Ψ0.25, 21 holes, 5mm (hole distance)

[0218] -Discharge rate: 6 ml / min

[0219] -Process air flow: 1,000 l / min

[0220] -Process air temperature: 260℃

[0221] -DCD (nozzle-collector distance): 250mm

[0222] -Belt moving speed (winding speed): 2.3 m / min

[0223] Examples 2 to 15 and Comparative Examples 1 and 2

[0224] Biodegradable melt-blown nonwoven fabrics were each prepared in the same manner as in Example 1, except that the components and process conditions were changed as shown in Table 1 below. Here, a polyhydroxyalkanoate (PHA) resin (3-HB-co-4-HB, manufacturer: CJ) composed of a second PHA resin (scPHA, 4-hydroxybutyrate (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.

[0225] [Table 1]

[0226]

[0227] [Test Example]

[0228] Test Example 1: Melt Flow Index

[0229] The melt flow index (g / 10 min) of the compositions for the biodegradable melt-blown nonwoven fabric 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 according to ASTM D1238.

[0230] Specifically, the melt flow index of the biodegradable pellets prepared by feeding the composition for the biodegradable melt-blown nonwoven fabric into a twin-screw extruder, mixing and melt-extruding was measured according to ASTM D1238.

[0231] Test Example 2: Tg and Tm

[0232] The glass transition temperature (Tg) and melting temperature (Tm) of the compositions for the biodegradable melt-blown nonwoven fabric prepared in Examples 8, 10 to 12, and 14 were measured using differential scanning calorimetry (DSC).

[0233] Specifically, 5 mg to 20 mg of each composition for a biodegradable melt-blown nonwoven fabric was placed in an aluminum pan, the temperature was increased from 40° C. to 180° C. at a rate of 10° C. / min using a differential scanning calorimeter, and then cooled to −50° C. at a rate of 10° C. / min to obtain a heat flow curve, from which the glass transition temperature (Tg) and the melting temperature (Tm) were measured.

[0234] Test Example 3: Td

[0235] The decomposition temperatures (Td) of the compositions for the biodegradable melt-blown nonwoven fabric prepared in Examples 8, 10 to 12, and 14 were measured using a thermogravimetric analyzer (TGA).

[0236] Specifically, the decomposition temperature (Td) was measured as the temperature at which the weight of each composition for biodegradable fiber decreased by 5% according to a weight change curve obtained by increasing the temperature from room temperature to 600° C. at a rate of 10° C. / min using a thermogravimetric analyzer (TGA).

[0237] [Table 2]

[0238]

[0239] Test Example 4: Diameter and standard deviation of biodegradable fibers

[0240] The diameter of fibers constituting each of the biodegradable melt-blown nonwoven fabrics prepared in Examples 1 to 15 and Comparative Examples 1 and 2 was measured using a scanning electron microscope (SEM), and the standard deviation thereof was calculated.

[0241] Test Example 5: Filtration efficiency of biodegradable meltblown nonwoven fabric

[0242] According to KS K ISO 9073-152007, at 38cm 2 The filtration efficiency of the biodegradable melt-blown nonwoven fabrics prepared in Examples 1 to 15 and Comparative Examples 1 and 2 at 0.3 μm and 0.5 μm was measured under the conditions of an area of ​​1000 μm and a pressure of 200 Pa. Specifically, particles having an average particle size of 0.3 μm and 0.5 μm were sprayed onto the nonwoven fabric to measure the filtration efficiency.

[0243] [Table 3]

[0244]

[0245]

[0246] As shown in Table 3 above, the biodegradable melt-blown nonwoven fabrics of Examples 1 to 15 had an average diameter of fibers constituting the same and a standard deviation thereof within a desired range, and the filtration efficiency of the nonwoven fabrics was also excellent.

[0247] Figure 1 is a scanning electron microscope (SEM, 100 times magnification) image of the biodegradable melt-blown nonwoven fabric of Example 14. Figure 2 is a scanning electron microscope (SEM, 1,000 times magnification) image of the biodegradable melt-blown nonwoven fabric of Example 14.

[0248] like Figure 1 and Figure 2 As shown, the biodegradable melt-blown nonwoven fabric of Example 14 has excellent uniformity in diameters of fibers constituting it.

Claims

1. A composition for a biodegradable meltblown nonwoven fabric, comprising a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, wherein the melt flow index (MFI) measured at 210° C. and 2.16 kg according to ASTM D1238 is 30 g / 10 min or higher. 2 . The composition for a biodegradable melt-blown nonwoven fabric according to claim 1 , wherein the PHA resin comprises a 4-hydroxybutyrate (4-HB) repeating unit in an amount of 0.1 wt % to 60 wt %.

3. The composition for a biodegradable melt-blown nonwoven fabric according to claim 1, wherein the PHA resin comprises a first PHA resin, the first PHA resin comprising a 4-hydroxybutyrate (4-HB) repeating unit in an amount of 15 wt % to 60 wt %, and having a melt flow index (MFI) of 0.1 g / 10 min to 20 g / 10 min when measured at 165° C. and 5 kg according to ASTM D1238.

4. The composition for a biodegradable melt-blown nonwoven fabric according to claim 1, wherein the PHA resin comprises a second PHA resin, the second PHA resin comprises a 4-hydroxybutyrate (4-HB) repeating unit in an amount of 0.1 wt % to 30 wt %, and has a melt flow index of 0.1 to 15 g / 10 min when measured at 165° C. and 5 kg according to ASTM D1238.

5. The composition for a biodegradable melt-blown nonwoven fabric according to claim 1, wherein the composition for a biodegradable melt-blown nonwoven fabric 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 a biodegradable melt-blown nonwoven fabric according to claim 5 , wherein a weight ratio of the PHA resin to the biodegradable resin is 1:99 to 99:

1. 7 . The composition for a biodegradable melt-blown nonwoven fabric according to claim 5 , wherein a weight ratio of the PHA resin to the polylactic acid (PLA) resin is 20:80 to 70:

30.

8. The composition for biodegradable melt-blown nonwoven fabric according to claim 1, wherein the composition for biodegradable melt-blown nonwoven fabric comprises at least one additive selected from the group consisting of: pigments, dye absorbers, light absorbers, antioxidants, compatibilizers, weighting agents, nucleating agents, melt strength agents, slip agents and fluidizers.

9. The composition for a biodegradable melt-blown nonwoven fabric according to claim 1, wherein the PHA resin further comprises at least one repeating unit selected from the group consisting of 3-hydroxybutyrate (3-HB), 3-hydroxypropionate (3-HP), 3-hydroxyhexanoate (3-HH), 3-hydroxyvalerate (3-HV), 4-hydroxyvalerate (4-HV), 5-hydroxyvalerate (5-HV) and 6-hydroxyhexanoate (6-HH).

10. The composition for a biodegradable melt-blown nonwoven fabric according to claim 1, wherein the composition for a biodegradable melt-blown nonwoven fabric has a melt flow index of 10 to 30 g / 10 min as measured at 190° C. and 2.16 kg according to ASTM D1238, and a weight average molecular weight of 500,000 g / mole or less.

11. A biodegradable melt-blown nonwoven fabric comprising biodegradable fibers, wherein the biodegradable fibers comprise a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and the average diameter of the biodegradable fibers is 10 μm or less, and the standard deviation of the average diameter is 1.3 or less.

12. The biodegradable melt-blown nonwoven fabric according to claim 11, wherein the biodegradable melt-blown 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 KISO 9073-152007, a total thickness of 0.05 mm to 20 mm, and a basis weight of 10 gsm to 500 gsm.

13. The biodegradable melt-blown nonwoven fabric according to claim 11, wherein the biodegradable melt-blown 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 according to KISO 9073-3:1989.

14. The biodegradable melt-blown nonwoven fabric according to claim 11, wherein the biodegradable fiber is a composite fiber of heterogeneous cross-section or a composite fiber of two or more or three or more components.

15. The biodegradable melt-blown nonwoven fabric according to claim 11, wherein the biodegradable melt-blown nonwoven fabric further comprises a functional coating on at least one side thereof.

16. A method for preparing a biodegradable meltblown nonwoven fabric, comprising: Melt extrusion of a composition for a biodegradable meltblown nonwoven fabric or pellets prepared therefrom, followed by spinning thereof, The composition for a biodegradable melt-blown nonwoven fabric comprises a polyhydroxyalkanoate (PHA) resin containing 4-hydroxybutyrate (4-HB) repeating units, and has a melt flow index (MFI) of 30 g / 10 min or more measured at 210° C. and 2.16 kg according to ASTM D1238.

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

18. The method for preparing a biodegradable melt-blown nonwoven fabric according to claim 16, wherein the spinning step is performed so that the basis weight of the biodegradable melt-blown nonwoven fabric prepared thereby is adjusted to 10 gsm to 500 gsm.

19. The method for preparing a biodegradable melt-blown nonwoven fabric according to claim 16, wherein the step of spinning the composition for a biodegradable melt-blown nonwoven fabric is performed using a sheath-core composite spinning device.

20. The method for preparing a biodegradable melt-blown nonwoven fabric according to claim 19, wherein the weight ratio of the raw materials to be fed to the core part and the sheath part is 5:95 to 95:

5. 21 . The method for preparing a biodegradable melt-blown nonwoven fabric according to claim 19 , wherein the composition for a biodegradable melt-blown nonwoven fabric is fed into a core part.

Images