Biodegradable fiber and fabric comprising same

Abstract

The present invention is characterized in that a biodegradable fiber comprises a main core yarn and an auxiliary core yarn, and has excellent biodegradability as well as enhanced durability, whereas durability was a problem of conventional biodegradable fibers.　That is, the biodegradable fiber according to the present invention is characterized by using a main core yarn and an auxiliary core yarn to secure durability and using a waterproof coating layer to compensate for the problems of conventional biodegradable resins due to moisture penetration.

Description

Biodegradable fibers and textile fabrics containing the same

[0001] The present invention relates to biodegradable fibers and fiber fabrics comprising the same.

[0002] Plastic products are now used in diverse fields, including not only food, clothing, and shelter, but also various industries, transportation, construction, environmental conservation, medicine, agriculture, fisheries, and leisure. However, most plastic products, developed and produced with the goal of high performance and long-term stability, do not decompose in the natural environment. Therefore, the disposal of large amounts of plastic waste is becoming a major social problem worldwide. Furthermore, it is estimated that millions of tons of plastic products flow into rivers and oceans each year, and this waste accumulates in the marine environment, contributing to marine pollution.

[0003] Furthermore, most synthetic plastics are petrochemical products, relying on petroleum as their raw material, which is rapidly depleting. Humanity currently uses approximately 90% of petroleum as fuel, and unless we reduce our petroleum consumption, this problem could worsen. Therefore, research into alternative materials for synthetic plastics, which are contributing to the problem of non-degradable waste, is necessary. As part of these efforts, interest in environmentally friendly plastics has recently grown.

[0004] Meanwhile, polyester resin is a synthetic resin with excellent heat resistance and mechanical properties. Among polyesters, polyethylene terephthalate resin, in particular, is one of the most widely used plastic materials and is also widely used in automobile bodies, furniture, and other components.

[0005] However, with the growing environmental concerns surrounding plastic waste, research into fully biodegradable plastics is actively underway. Because polyethylene terephthalate generally lacks biodegradation or biodegradation properties, imparting biodegradability to it could potentially address some of these environmental concerns. Biodegradable polyester refers to materials that can be broken down by naturally occurring microorganisms, such as bacteria, algae, and fungi.

[0006] In particular, biodegradable fibers are fibers that can be broken down by bacteria, microorganisms, and other organic organisms. Demand is growing as a substitute for non-biodegradable fibers due to increasingly stringent environmental regulations stemming from the worsening environmental pollution caused by existing non-biodegradable fibers. Furthermore, they are currently being utilized in diverse industries, including packaging, electronics, automotive, building materials, marine, stationery, and pulp and paper.

[0007] Examples of biodegradable fibers include PBS, PHA, PBAT, and PLA. Among these, PLA is an environmentally friendly, plant-derived, versatile resin that exhibits biodegradability under natural environmental and waste disposal conditions and possesses a relatively high melting point compared to other biodegradable fibers. Consequently, its high heat resistance and practicality have led to its active development and application.

[0008] In addition, PBAT fiber is being actively developed and applied as a fossil fuel-based biodegradable fiber due to its excellent tensile strength, tear strength, durability, biodegradability, and processability.

[0009] However, PLA fibers lack flexibility and ductility, which, when used alone, reduces mechanical strength when thermally bonding webs formed from spun PLA fibers or bonding them with adhesives. Furthermore, PBAT fibers are expensive to produce and have low heat resistance, making them unsuitable for high-temperature applications when used alone.

[0010] Accordingly, research is being conducted on alternative materials for non-degradable polymers as a solution to environmental problems, and some advanced countries are producing polylactic acid with excellent physical properties and degradability by producing raw materials from surplus agricultural products such as corn, and are researching technology to synthesize polyester that can be degraded by microorganisms.

[0011] The chemical fiber industry is also actively researching biodegradable fibers and products using biodegradable polyester. However, biodegradable chemical products are expensive and have limited commercial viability, including durability. Furthermore, biodegradable polyesters can suffer from hydrolysis of ester bonds in atmospheric moisture and high-humidity environments, degrading the physical properties of the final product.

[0012] Previous attempts have been made to blend polyethylene terephthalate (PET) with biodegradable polyesters, such as polylactic acid (PA). However, while biodegradable materials like PLA, PBA, and PCL possess excellent biodegradability, their low melting points hinder their application to textile and apparel products due to their poor heat resistance and durability.

[0013] Meanwhile, research and development are also actively underway into binder fibers capable of bonding the filaments or single fibers that make up nonwoven webs or sheets. Recently, a polyester binder composite fiber has been developed that utilizes polyester as a binder fiber while addressing processing challenges.

[0014] However, even in the case of polyester binder composite fibers that have overcome the difficulties in the process, the same environmental problems as above are still occurring.

[0015] Therefore, continuous research on biodegradable fibers that can solve the above environmental problems is necessary.

[0016] The present invention relates to a biodegradable fiber, and its main feature is that it can enhance biodegradability while securing durability and moisture properties.

[0017] One embodiment of the present disclosure provides a biodegradable fiber comprising a core yarn comprising polypropylene, polylactic acid (PLA), amylopectin starch as a thermoplastic starch, amylose starch as a thermoplastic starch, and a metal; a subcore yarn comprising polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT); and a coating layer surrounding the core yarn and the subcore yarn, wherein the coating layer comprises a coating layer composition comprising reactive silicone, styrene butadiene rubber, and polyvinyl chloride.

[0018] One embodiment of the present specification provides a biodegradable fiber comprising 10 parts by weight or more and 30 parts by weight or less of the thermoplastic starch based on 100 parts by weight of the main ingredient, and wherein the thermoplastic starch comprises amylopectin starch and amylose starch in a weight ratio of 1:1.

[0019] One embodiment of the present specification provides a biodegradable fiber comprising: 50 parts by weight or more and 70 parts by weight or less of the polypropylene; and 10 parts by weight or more and 30 parts by weight or less of the polylactic acid, based on 100 parts by weight of the main fiber.

[0020] One embodiment of the present application provides a biodegradable fiber comprising, based on 100 parts by weight of the above-mentioned auxiliary agent, 70 parts by weight or more and 90 parts by weight or less of the polylactic acid; and 10 parts by weight or more and 30 parts by weight or less of the polybutylene adipate terephthalate (PBAT).

[0021] One embodiment of the present application provides a biodegradable fiber in which the styrene butadiene rubber has a butadiene content of 40 wt% or less.

[0022] In one embodiment of the present application, a biodegradable fiber is provided, which comprises 40 to 60 parts by weight of the reactive silicone, 5 to 15 parts by weight of the styrene butadiene rubber, and 30 to 50 parts by weight of the polyvinyl chloride, based on 100 parts by weight of the coating layer composition.

[0023] In one embodiment of the present application, a biodegradable fiber is provided, wherein the thickness of the coating layer is 0.1 nm or more and 10 nm or less.

[0024] In one embodiment of the present application, a biodegradable fiber is provided in which the ratio of the main and secondary fibers is 1:1 to 1:3.

[0025] Finally, a textile fabric comprising a biodegradable fiber according to the present application is provided.

[0026] The biodegradable fiber of one embodiment of the present disclosure comprises a core yarn and a sub-core yarn, and is characterized by excellent biodegradability as well as enhanced durability, which is a problem of existing biodegradable fibers. That is, in the case of existing biodegradable fibers, the core yarn having a single composition was used to manufacture the fabric, which resulted in a problem of poor durability, but the biodegradable fiber according to the present application has the characteristic of being biodegradable and at the same time, enhanced durability by using the core yarn and sub-core yarn differently.

[0027] Furthermore, the biodegradable fiber according to the present application is characterized by including a coating layer on the fiber itself including the main and sub-core yarns, and further enhancing durability by including a coating layer containing a waterproof material.

[0028] That is, in the case of the biodegradable fiber according to the present application, the main and secondary yarns were utilized to ensure durability, and in particular, the main feature is that the aforementioned problem was solved by using a waterproof coating layer of a specific composition to further supplement the problem of the existing biodegradable resin due to moisture penetration.

[0029] Figure 1 is a diagram briefly showing a process for manufacturing a biodegradable fiber according to the present invention.

[0030] Before explaining the invention, the definitions of each term are as follows.

[0031] The present invention may have various modifications and take various forms, and it should be understood that it includes all modifications, equivalents, and substitutes included in the spirit and technical scope of the present invention.

[0032] Hereinafter, the present invention will be described in detail.

[0033] The biodegradable fiber according to the present application comprises a primary and secondary fiber. That is, the biodegradable fiber according to the present application is characterized by using two different types of fibers in combination.

[0034] The main examination according to the present application includes polypropylene, polylactic acid (PLA), amylopectin starch as thermoplastic starch, amylose starch as thermoplastic starch, and metal.

[0035] For example, PLA fiber, a biodegradable fiber, is an environmentally friendly, plant-derived, general-purpose resin that exhibits biodegradability under natural environmental and waste disposal conditions and possesses a relatively high melting point compared to other biodegradable fibers. Consequently, its high heat resistance and practicality have led to its active development and application. However, PLA fiber lacks flexibility and ductility. When used alone, PLA fibers exhibit reduced mechanical strength when thermally bonding webs formed from spun PLA fibers or bonding them with adhesives.

[0036] Accordingly, the main examination according to the present application is characterized by including polypropylene in addition to polylactic acid (PLA), amylopectin starch as thermoplastic starch, amylose starch as thermoplastic starch, and a metal.

[0037] That is, the problem of using only existing polylactic acid is solved by including more polypropylene, and the main feature is that it includes thermoplastic starch to further enhance the biodegradability characteristics.

[0038] In one embodiment of the present application, the polypropylene may contain 50 parts by weight or more and 70 parts by weight or less based on 100 parts by weight of the main examination material.

[0039] In another embodiment, the polypropylene may be comprised of 50 parts by weight or more and 70 parts by weight or less, specifically 55 parts by weight or more and 65 parts by weight or less, and more specifically 60 parts by weight based on 100 parts by weight of the main ingredient.

[0040] In one embodiment of the present application, the polylactic acid is included in an amount of 10 parts by weight or more and 30 parts by weight or less based on 100 parts by weight of the main ingredient.

[0041] In another embodiment, the polylactic acid may be included in an amount of 10 parts by weight or more and 30 parts by weight or less, preferably 15 parts by weight or more and 20 parts by weight or less, based on 100 parts by weight of the main ingredient, and specifically 18 parts by weight or more.

[0042] As described above, rather than using polylactic acid alone, it is used in combination with polypropylene and the above weight portion, thereby improving heat resistance and practicality.

[0043] In the present application, the main agent includes thermoplastic starch.

[0044] The thermoplastic starch above can be made using starch extracted from potatoes (OTTO potatoes from Youngheung Foods, available commercially) as starch powder, and thermoplastic starch (TPS) can be manufactured by mixing glycerol, a plasticizer, into potato starch.

[0045] In one embodiment of the present application, the thermoplastic starch may be included in an amount of 10 parts by weight or more and 30 parts by weight or less based on 100 parts by weight of the main examination material.

[0046] In another embodiment, the thermoplastic starch may be included in an amount of 10 parts by weight or more and 30 parts by weight or less, more specifically 15 parts by weight or more and 25 parts by weight or less, specifically 20 parts by weight, based on 100 parts by weight of the main ingredient.

[0047] At this time, in the present application, amylopectin starch and amylose starch are included as thermoplastic starch, and the weight ratio can satisfy 1:1.

[0048] According to one embodiment of the present invention, the metal may be selected from the group consisting of Ca, K, Cu, Zn, Mg, Fe, Mn, and Ni.

[0049] As described above, a very small amount of metal is added to the thermoplastic starch mixture to induce biodegradation of polypropylene.

[0050] As a result of evaluating the biodegradability of copper, zinc, and potassium, it was confirmed that potassium (K) relatively promotes the decomposition of polypropylene under industrial and soil conditions, and more specifically, K can be used.

[0051] In the present application, the secondary examination may include polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT).

[0052] PBAT fibers, a biodegradable fiber derived from fossil fuels, are being actively developed and applied due to their superior tensile strength, tear strength, durability, biodegradability, and processability. However, as previously mentioned, PLA fibers lack flexibility and ductility. Therefore, when used alone, webs formed from spun PLA fibers are thermally bonded or resin-bonded with adhesives, resulting in reduced mechanical strength. Furthermore, PBAT fibers are expensive to produce and have low heat resistance, making them unsuitable for high-temperature applications.

[0053] Accordingly, in the case of the secondary examination according to the present application, it is characterized by using a mixture of polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT).

[0054] In the present application, a biodegradable fiber is provided, wherein the polylactic acid is contained in an amount of 70 parts by weight or more and 90 parts by weight or less based on 100 parts by weight of the above-mentioned auxiliary agent; and the polybutylene adipate terephthalate (PBAT) is contained in an amount of 10 parts by weight or more and 30 parts by weight or less.

[0055] In another embodiment, the polylactic acid may be included in an amount of 70 parts by weight or more and 90 parts by weight or less, specifically 75 parts by weight or more and 85 parts by weight or less, and more specifically 80 parts by weight based on 100 parts by weight of the above-mentioned auxiliary agent.

[0056] In another embodiment, the polybutylene adipate terephthalate (PBAT) may be included in an amount of 10 parts by weight or more and 30 parts by weight or less, specifically 15 parts by weight or more and 25 parts by weight or less, based on 100 parts by weight of the above-described auxiliary agent, and may be more specifically included in an amount of 20 parts by weight or more.

[0057] As described above, the biodegradable fiber according to the present application comprises a core yarn and a sub-core yarn, and is characterized by excellent biodegradability as well as enhanced durability, which is a problem with existing biodegradable fibers. That is, in the case of existing biodegradable fibers, the core yarn having a single composition was used to manufacture the fabric, which resulted in a problem of poor durability, but the biodegradable fiber according to the present application is characterized by enhanced durability by using the core yarn and sub-core yarn differently while being biodegradable.

[0058] In the present application, a biodegradable fiber is provided in which the ratio of the main and secondary examinations is 1:1.

[0059] The ratio of the above main and sub-main threads can be expressed as 1:1 when the fibers of a certain length have the same weight, and can specifically mean fibers mixed one strand at a time.

[0060] The present application relates to a biodegradable fiber comprising a core and a subcore as described above. Using the aforementioned composition and content, the fiber exhibits both superior biodegradability and durability. Furthermore, the biodegradable fiber according to the present application utilizes core and subcore yarns to ensure durability. Furthermore, the biodegradable fiber further addresses the issues associated with moisture penetration in conventional biodegradable resins by utilizing a waterproof coating layer of a specific composition.

[0061] That is, in relation to the existing problem of durability, physical durability can be solved through the main and secondary examinations as described above, but when used as a fiber, the reduction in chemical durability due to penetration of external substances such as moisture has been a problem, and accordingly, the biodegradable fiber according to the present application is characterized by including a coating layer containing a specific composition.

[0062] In one embodiment of the present application, a biodegradable fiber is provided, wherein the coating layer comprises a coating layer composition comprising reactive silicone, styrene butadiene rubber, and polyvinyl chloride.

[0063] At this time, the styrene butadiene rubber may have a butadiene content of 40 wt% or less.

[0064] Specifically, the styrene butadiene rubber may have a butadiene content of 30 wt% or more and 40 wt% or less, and specifically 35 wt%.

[0065] Butadiene (BD) has a conjugation bond (1.5 bond) that rapidly changes between double bonds and single bonds, and has free radicals and high adhesion to surrounding components.

[0066] Therefore, when the above-mentioned butadiene (BD) is included in the above content, a coating layer can be formed more stably by receiving radicals from the component of the butadiene included in a specific weight portion.

[0067] In one embodiment of the present application, a biodegradable fiber is provided, which comprises 40 to 60 parts by weight of the reactive silicone, 5 to 15 parts by weight of the styrene butadiene rubber, and 30 to 50 parts by weight of the polyvinyl chloride, based on 100 parts by weight of the coating layer composition.

[0068] In one embodiment of the present application, the reactive silicone may be comprised in an amount of 40 parts by weight or more and 60 parts by weight or less, specifically 45 parts by weight or more and 55 parts by weight, based on 100 parts by weight of the coating layer composition, and may specifically comprise 55 parts by weight.

[0069] In one embodiment of the present application, the styrene butadiene rubber may be included in an amount of 5 parts by weight or more and 15 parts by weight or less, specifically 10 parts by weight or more and 13 parts by weight or less, based on 100 parts by weight of the coating layer composition, and more specifically 10 parts by weight or more.

[0070] In one embodiment of the present application, the polyvinyl chloride may be contained in an amount of 30 parts by weight or more and 50 parts by weight or less, specifically 35 parts by weight or more and 45 parts by weight or less, based on 100 parts by weight of the coating layer composition, and preferably 40 parts by weight or more.

[0071] By using a material having the above composition and especially a styrene-butadiene rubber having the above composition, the water resistance characteristics are further enhanced, and also, when applied to a fiber, it has the characteristic of preventing stickiness due to the adhesive component.

[0072] In the present application, the thickness of the coating layer may be 0.1 nm or more and 10 nm or less, more specifically 1 nm or more and 5 nm or less, and even more specifically 2 nm or more and 4 nm or less.

[0073] The coating layer can secure durability against chemical penetration such as moisture by satisfying the above range, and at the same time, it can provide flexibility when manufactured with fibers, so that durability does not decrease even after long-term use.

[0074] As shown in Fig. 1, the step of simultaneously extracting and mixing the main and sub-strains (1) and (2), and then introducing them into a coating machine (3) containing a coating composition, followed by heat treatment (4) may be included. At this time, the heat treatment may shrink the main and sub-strains by heat treating them at 80 to 160°C.

[0075] Hereinafter, the present invention will be described through examples and comparative examples. These examples are merely illustrative and the present invention is not limited thereto.

[0076] <Manufacturing Example>

[0077] Potato starch (commercially available from Youngheung Foods) was used as the thermoplastic starch. Glycerol, a plasticizer, was mixed with potato starch to produce thermoplastic starch (TPS). The glycerol content ranged from 20 to 35 wt.%, and TPS was produced using a twin-screw extruder.

[0078] After this, the main and secondary examinations were manufactured with the corresponding compositions and contents as shown in Table 1 below.

[0079] Main examination Sub-examination Polypropylene Polylactic acid Amylopectin Starch Amylose Starch Metal (K) Polylactic acid Polybutylene Adipate Terephthalate Example 16018101028020 Comparative example 1601810102--Comparative example 2-----8020

[0080] After this, the fibers manufactured above were simultaneously extracted into the main fiber (1) and the sub-fiber (2) as in Fig. 1, mixed, and then fed into a coating machine (3) containing a coating composition, followed by heat treatment (4). At this time, the coating layer composition was used by mixing reactive silicone, styrene butadiene rubber with 35% butadiene component, and polyvinyl chloride in a weight ratio of 50:10:40, and the heat treatment was maintained at 100°C to 120°C.

[0081] It was confirmed that the thickness of the generated coating layer was approximately 2 nm.

[0082] <Comparative Example 3>

[0083] In the above Example 1, it was manufactured in the same manner as in the above Example 1, except that the coating layer was not formed.

[0084] <Reference Example 4>

[0085] In the above Example 1, the same process as in Example 1 was performed except that a styrene-butadiene rubber having a butadiene component of 81% was used instead of a styrene-butadiene rubber having a butadiene component of 35%.

[0086] The following experiments were conducted on the biodegradable fiber manufactured above.

[0087] (1) Strength and elongation: Measured using Instron’s UTM in accordance with KS K 0412.

[0088] (2) Biodegradability: Biodegradability was measured after 180 days using the ISO21701 method.

[0089] (3) Durability: Tensile strength was measured for fibers using ASTM D-2256.

[0090] (4) Moisture resistance: The fibers were stored in a glass box with a humidity of 40% for 30 days, and the strength until breakage was compared by applying strength to the fibers.

[0091] The results for each are shown in Table 2 below.

[0092] Strength (g / d) Elongation (%) Biodegradability (% / 180 days) Durability (g / den) Moisture resistance Example 14.120.761.841.117N / cm2 Comparative Example 13.821.659.230.815 N / cm2 Comparative Example 23.621.758.329.216 N / cm2 Comparative Example 33.918.259.135.27 N / cm2 Reference Example 43.821.659.436.413 N / cm2

[0093] As can be seen from the above examples, comparative examples, and reference examples, all biodegradable fibers were found to be excellent in elongation and biodegradability evaluations. However, in the case of Example 1 according to the present application, it was found to be superior to other comparative examples in strength and durability evaluations, and furthermore, it was found to be superior to other comparative examples or reference examples in moisture resistance by including a coating layer of a specific composition.

[0094] Specifically, in the case of Comparative Examples 1 and 2, in which only one main examination and one sub-examination according to the present application were included, the biodegradability was similar to that of Example 1, but it was confirmed that the durability evaluation was lower than that of Example 1. However, in the case of moisture resistance, it was confirmed that it was superior to other comparative examples by including a coating layer.

[0095] In the case of Comparative Example 3, in which a coating layer was not used, the durability itself was superior to Comparative Examples 1 and 2, but it was inferior to the example, and in particular, it was confirmed that the moisture resistance was greatly reduced.

[0096] Lastly, Reference Example 4 used SBR with a butadiene content exceeding a certain range, and it was confirmed that this also had superior moisture resistance and durability compared to the comparative example, but was inferior to Example 1.

Claims

1. A main material comprising polypropylene, polylactic acid (PLA), amylopectin starch as a thermoplastic starch, amylose starch as a thermoplastic starch, and a metal; Sub-inspection materials including polylactic acid (PLA) and polybutylene adipate terephthalate (PBAT); and A coating layer surrounding the above main and sub-main examinations; Biodegradable fibers containing A biodegradable fiber comprising a coating layer composition comprising reactive silicone, styrene butadiene rubber and polyvinyl chloride.

2. In claim 1, Based on 100 parts by weight of the above main ingredient, the thermoplastic starch contains 10 parts by weight or more and 30 parts by weight or less, The above thermoplastic starch is a biodegradable fiber comprising amylopectin starch and amylose starch in a weight ratio of 1:

1.

3. In claim 1, A biodegradable fiber comprising: 50 parts by weight or more and 70 parts by weight or less of the polypropylene; and 10 parts by weight or more and 30 parts by weight or less of the polylactic acid, based on 100 parts by weight of the main ingredient.

4. In claim 1, A biodegradable fiber comprising, based on 100 parts by weight of the above-mentioned auxiliary agent, 70 parts by weight or more and 90 parts by weight or less of the above-mentioned polylactic acid; and 10 parts by weight or more and 30 parts by weight or less of the above-mentioned polybutylene adipate terephthalate (PBAT).

5. In claim 1, The above styrene butadiene rubber is a biodegradable fiber having a butadiene content of 40 wt% or less.

6. In claim 1, A biodegradable fiber comprising 40 to 60 parts by weight of the reactive silicone, 5 to 15 parts by weight of the styrene butadiene rubber, and 30 to 50 parts by weight of the polyvinyl chloride, based on 100 parts by weight of the coating layer composition.

7. In claim 1, A biodegradable fiber having a thickness of the coating layer of 0.1 nm or more and 10 nm or less.

8. In claim 1, A biodegradable fiber having a ratio of the main and sub-main components of 1:

1.

9. A textile fabric comprising a biodegradable fiber according to any one of claims 1 to 8.

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