fibres

Abstract

The present invention relates to a fiber obtainable by or obtained by a process comprising the steps of: - spinning a melt of an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate through a hollow fiber spinning nozzle to obtain a precursor fiber; and - cooling the precursor fiber under a temperature gradient, thereby obtaining a fiber. The present invention also relates to yarns and apparel made from such fibers and to a process for making such fibers.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority to European Patent Application No. 21196170.1, filed on September 10, 2021, with the European Patent Office, the entire contents of which are incorporated herein by reference for all purposes. Technical Field

[0003] This invention relates to a fiber comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate, a method for preparing such fiber, and the use of such fiber in yarn or textiles. Background of the Invention

[0005] Sustainable textiles should be based on ecological, economic, and social sustainability. Sustainable products should take into account factors from raw materials to processing, finishing, sales, and recycling.

[0006] Fibers currently used in sustainable textiles include, for example, natural fibers such as cotton, wool, linen, and SeaCell. TM (Cellulose fibers obtained from algae, produced by SmartFiber AG), recycled fibers such as recycled polyester (e.g., from polyethylene terephthalate (PET) bottles), (Recycled nylon fibers) or regenerated fibers (regenerated fibers are the name for fibers produced from natural materials such as wood through chemical methods), such as Lyocell (e.g., under the trade name Tencel). TM (Originally from Lenzing) or Modal.

[0007] However, despite their use in sustainable textiles, these fibers still have various drawbacks. For example, the production of cotton and wool requires high water consumption, which is accompanied by high land consumption. Obtaining recycled fibers, such as recycled PET, typically requires significant amounts of energy, water, and chemicals.

[0008] Further, it is desired that sustainable textiles and fibers be suitable for use under the concept of a circular economy. In particular, it is hoped that textiles and fibers can be used in biological cycles by exhibiting suitable biodegradability and thus avoiding non-degradable waste, for example, in cradle-to-cradle designs. A beneficial induction of fibers or textiles into the biological cycle is achieved when textile products are returned after their life cycle and fed into industrial composting. This generates biomass and biogas (CH4, CO2, water), which can be directly fed into the biological cycle.

[0009] Therefore, there is a continuous demand for fibers, especially fibers that meet ecological requirements. Therefore, the object of this invention is to provide such fibers.

[0010] Invention Summary

[0011] This objective is achieved by fibers, yarns, clothing, and methods having the features of the independent claims.

[0012] In a first aspect, the present invention relates to fibers that can be obtained or acquired by methods including:

[0013] - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; and

[0014] - The precursor fibers are cooled under a temperature gradient to obtain fibers.

[0015] Secondly, the present invention relates to fibers made from mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates.

[0016] The fiber comprises two parts in the longitudinal direction, one part being a thicker part and the other part being a thinner part. The thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction.

[0017] At least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a compact structure.

[0018] Thirdly, the present invention relates to a hollow fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0019] Fourthly, the present invention relates to a yarn comprising the fibers of the present invention.

[0020] Fifthly, the present invention relates to a textile comprising the fiber or yarn of the present invention.

[0021] Sixthly, the present invention relates to a method for preparing fibers according to the present invention, comprising:

[0022] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0023] - The precursor fibers are cooled under a temperature gradient to obtain fibers.

[0024] In a seventh aspect, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined herein.

[0025] Eighthly, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

[0026] Ninthly, the present invention relates to a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate.

[0027] In a tenth aspect, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers, wherein the fibers are as defined herein.

[0028] Eleventhly, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

[0029] Brief description of the attached figures

[0030] The invention will be better understood when considered in conjunction with the non-limiting embodiments and the accompanying drawings, and with reference to the detailed description, in which:

[0031] Figure 1 A schematic diagram of a melt spinning apparatus for preparing fibers according to an embodiment of the present invention is shown, wherein precursor fibers are cooled under a temperature gradient.

[0032] Figure 2A A photograph shows a melt spinning apparatus that can be used to prepare fibers according to embodiments of the present invention. The oval shape highlights the air-cooled aggregates of the melt spinning apparatus. Figure 2B A photograph shows another melt spinning apparatus that can be used to prepare fibers according to embodiments of the present invention. The oval shape again highlights the air-cooled aggregates of the melt spinning apparatus.

[0033] Figure 3 A schematic diagram of a fiber production process is shown, which includes further processing of the fibers on a fiber post-processing line according to an embodiment of the invention.

[0034] Figure 4 This shows the various fibers commonly used in the production of textiles. From left to right, fibers include coarse wool, fine wool, alpaca wool, cashmere, silk, linen, cotton, and polyester.

[0035] Figure 5A A schematic representation of a fiber according to an embodiment of the invention is shown. The fiber includes a thicker portion having cavities and a thinner portion having a compact or dense structure. Figure 5B An electron micrograph of a fiber according to an embodiment of the invention is shown, the fiber having a thicker portion and a thinner portion (relative to each other). Figure 5C An electron micrograph of a thinner portion of a fiber according to an embodiment of the invention is shown, the thinner portion being located between two thicker portions. Figure 5D An electron micrograph of a fiber cross-section according to an embodiment of the present invention is shown, in which the cavity can be seen. Figure 5E Further electron micrographs showing cross-sections of fibers according to embodiments of the invention are shown. The three micrographs in the upper figure and the middle micrograph in the lower figure show cross-sections of the thicker portions of the fiber, which include cavities. The left and right micrographs in the lower figure show cross-sections of the thinner portions of the fiber, which have a compact or dense structure. Figure 5F An electron micrograph showing a portion of the outer wall of a fiber cavity according to an embodiment of the present invention.

[0036] Figure 6A The setup for testing the hygroscopicity of cotton fibers, fibers according to embodiments of the present invention (obtained by cooling under a temperature gradient), polyester fibers, and polybutylene succinate fibers is shown (from left to right). Figure 6B The test setup (from left to right) for the hygroscopicity of cotton fibers, fibers according to an embodiment of the invention (obtained by cooling under a temperature gradient), polyester (PES) fibers, and polybutylene succinate (PBS) fibers immediately before testing is shown. Four fiber balls were simultaneously immersed in a colored liquid to a depth of approximately 1 cm. Measurements were taken as soon as the fiber balls were immersed in the liquid. Figure 6C The test is shown approximately 13 seconds after the fiber ball was immersed in the liquid. Figure 6D The results show that after immersing the fiber balls in the liquid for approximately 3.5 minutes, the dyeing of the cotton fibers and the fibers according to embodiments of the invention (obtained by cooling under a temperature gradient) is visible. Typically, the dyeing of the cotton fibers and the fibers according to embodiments of the invention can be observed after immersing the fiber balls in the liquid for two minutes. Figure 6E The images show that after immersing the fiber balls in the liquid for 6 minutes, the portions of the cotton fibers and fibers according to an embodiment of the invention (obtained by cooling under a temperature gradient) immersed in the liquid swell significantly. The PBS fiber balls show very slight staining in the middle. Figure 6F The test was stopped immediately after the fiber ball was immersed in the liquid for 15 minutes. It can be seen that the fiber ball containing fibers according to an embodiment of the invention (obtained by cooling under a temperature gradient, second from the left) substantially retains its shape. In the fiber ball according to an embodiment of the invention (second from the left), the liquid has risen to a higher position than in the cotton fiber ball (first from the left). At the bottom of the cotton fiber ball, clumping caused by expansion can be observed.

[0037] Figure 7 The experiment shows the drying of fiber balls in a petri dish at 40°C for 10 minutes.

[0038] Figure 8A schematic diagram of a hollow fiber according to an embodiment of the present invention is shown, the hollow fiber having a continuous cavity.

[0039] Figure 9A A photograph is shown of a shirt made using fibers (particularly yarns made from such fibers) according to an embodiment of the invention, obtained by cooling under a temperature gradient. Figure 9B Another view shows a shirt made using fibers according to an embodiment of the invention, particularly yarns made from such fibers. Figure 9C Another view shows a shirt made using fibers according to an embodiment of the invention, particularly yarns made from such fibers. Invention Details

[0041] As described above, in a first aspect, the present invention relates to a fiber that can be obtained by or by a method comprising the following steps:

[0042] - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; and

[0043] - The precursor fibers are cooled under a temperature gradient to obtain fibers.

[0044] It has been surprisingly discovered that a fiber can be obtained by a method comprising the following steps or by the following steps: spinning a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate through a hollow fiber spinning nozzle to obtain a precursor fiber; and cooling the precursor fiber under a temperature gradient to obtain a fiber having equal or better hygroscopic properties than cotton (see Example 3 below). In other words, the fiber of the present invention has hydrophilicity similar to cotton. It has also been surprisingly discovered that the time required to dry the fiber of the present invention is significantly shorter than the time required to dry cotton (see Example 3). Therefore, the fiber of the present invention can be used, for example, to produce surfaces, particularly textiles, that absorb moisture and allow them to be re-dried with less energy than cotton. Thus, as an advantage, the fiber of the present invention has similar or even better properties than cotton in terms of hydrophilicity and drying behavior. However, as another significant advantage, the preparation of the fiber requires much less water and land consumption than cotton (see Example 4). As another advantage, the production of the fiber can be carried out without toxic substances, such as antimony (see Example 2). Furthermore, by using aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates, biodegradable fibers, even those conforming to the harmonious European standard EN 13432, can be obtained, thus allowing for processing in industrial composting plants. The fibers of this invention can be used as textile fibers, for example, for producing clothing such as shirts (see Example 5 and...). Figure 9A , 9B(and 9C). It was found that this garment is biodegradable, even to the extent that it completely degrades / decomposes within just a few weeks after being placed in organic waste. It should be noted that various products, such as sheets and foils, and fibers comprising one or more of aliphatic polyesters, aliphatic-aromatic polyesters, and / or polyhydroxyalkanoates, are described in, for example, EP3626767, WO 2010 / 034689, WO 2010 / 034711, WO 2015 / 169660, EP1966419, EP2984138, CN 103668540, CN 103668541, WO 2014 / 173055, and CN 104120502. However, these documents only describe conventional processing methods for these polymers.

[0045] As used herein, the term "precursor fiber" generally refers to the fiber that appears as an intermediate during the manufacturing process of this invention, after leaving the hollow fiber spinning nozzle and during cooling under a temperature gradient. The (final) fiber of this invention, obtained by this method or obtained by this method, especially after cooling under a temperature gradient, is generally referred to simply as "fiber".

[0046] Surprisingly, it has also been found that a fiber can be obtained by a method comprising the following steps or by the following steps: spinning a melt comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate through a hollow fiber spinning nozzle to obtain a precursor fiber; and cooling the precursor fiber under a temperature gradient to obtain the fiber having a specific structure comprising a thicker portion and a thinner portion, wherein the thicker portion may have a cavity, and wherein the thinner portion may have a dense or compact structure. Therefore, the invention also relates to a fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, wherein the fiber comprises two portions in the longitudinal direction, wherein one portion is a thicker portion and the other portion is a thinner portion, wherein the thicker portion and the thinner portion extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker portion in the vertical direction is greater than the extension of the thinner portion in the vertical direction; wherein at least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a compact structure. Because fibers consist of thicker portions with cavities and thinner portions with compact structures, they can also be called segmented fibers or segmented hollow fibers. For example, in Figure 5A and 5BThe diagram illustrates an optical fiber (thicker portion 15, thinner portion 17, and cavity 19) with a thicker portion and a thinner portion having a cavity, according to an embodiment of the invention. Without wishing to be bound by theory, this document assumes that this structure, including the thicker portion with the cavity and the thinner portion with a dense structure, is produced by the partial fusion of adjacent hollow fiber portions during the cooling of the precursor fiber under a temperature gradient.

[0047] As used herein, the term "cavity" generally refers to a hollow space existing within the cross-section of a fiber, for example... Figure 5A , 5B The top image and the middle bottom image of 5D and 5E, and... Figure 5F As shown. The cavity can be filled with gas, such as air. The term "dense structure," also known as "compact structure," generally refers to fibrous materials existing in a substantially dense or compact form, especially when compared to the cavities of the fibers, for example... Figure 5E The structures shown in the lower left and lower right figures. However, the terms "dense structure" or "compact structure" can also include structures containing pores, for example... Figure 5E As shown in the lower left and lower right images.

[0048] The melt for spinning fibers can be produced using any method known to those skilled in the art for producing melts of spun fibers. As an illustrative example, aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can be mixed in an unmelted state, for example, by mixing polymer particles, optionally with one or more other additives. Optionally, the polymer and additives (if present) can be dried before mixing and preparing the melt. Then, to prepare the melt, the mixture can be heated to the melting point of the polymer or above. As an illustrative example, mixing and heating can be carried out in an extruder. As an illustrative example, the melt can be heated to a temperature of 250°C. The melt is then passed through a hollow fiber spinning nozzle. As an illustrative example, an extruder can be used to pass the melt through a hollow fiber spinning nozzle. Any hollow fiber spinning nozzle commonly known in the art can be used, such as the hollow fiber spinning nozzle described in EP2112256, the entire contents of which are incorporated herein by reference. Spinning a melt containing aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates through a hollow fiber spinning nozzle yields hot precursor fibers. The hot precursor fiber obtained by spinning the melt through a hollow fiber spinning nozzle is cooled under a temperature gradient to obtain the fiber.

[0049] The temperature gradient can be generated by any suitable means / device capable of generating a temperature gradient for use in this invention. The temperature gradient can be generated, for example, by one or more temperature control elements. As an illustrative example, the temperature gradient can be generated by arranging and / or operating temperature control elements within or near the spinning apparatus. Equipment for melt spinning is generally known to those skilled in the art (see, for example...). Figure 2A and 2B (This shows a conventional melt spinning device). The temperature control element can be a heating and / or cooling element that can actively or passively provide heating or cooling effects to the precursor fiber. With such a temperature control element, a selected side / surface area of ​​the precursor fiber can be cooled, for example, such that one side / surface area of ​​the precursor fiber is cooled, while another surface area, typically the surface area opposite the selected side / surface area, is heated or at least maintained at the temperature present after leaving the nozzle of the spinning device. An exemplary, and not limiting, example of a temperature control element as a cooling element is air-cooled aggregate. As an illustrative example of a temperature gradient, the precursor fiber can leave the spinning nozzle at a temperature of approximately 250°C. A temperature gradient is then generated, for example, by cooling the precursor fiber with air from one side. Thus, air cooling can be achieved by using air-cooled aggregate arranged on one side of the precursor fiber (see, for example...). Figure 1 The precursor fiber 3 and the airflow 7) are provided with airflow to the precursor fiber from only one side in a direction substantially perpendicular to the longitudinal direction of the precursor fiber. The air used for air cooling may have an ambient temperature, preferably room temperature, and more preferably a temperature of +20°C + / -5°C.

[0050] One or more temperature control elements may be arranged such that a temperature gradient is generated in a direction substantially perpendicular to the longitudinal direction of the precursor fiber. It is also suitable to arrange one or more temperature control elements such that a temperature gradient is generated in a direction substantially parallel to the cross-section of the precursor fiber.

[0051] Preferably, one or more temperature control elements are arranged such that the temperature on the outer surface of the precursor fiber is lower than the temperature on the opposite outer surface. Specifically, one or more temperature control elements may be arranged such that the precursor fiber is cooled from one side. Preferably, cooling is achieved by air cooling. Preferably, air cooling can be achieved by using air-cooled aggregate arranged on one side of the precursor fiber (see, for example...). Figure 1This is achieved by providing an airflow from one side to the precursor fiber (precursor fiber 3 and airflow 7) in a direction substantially perpendicular to the longitudinal direction of the precursor fiber. Airflow from one side to the other can be prevented by cutting off the air-cooled aggregate arranged on opposite sides of the precursor fiber. Airflow from one side to the other can also be prevented by arranging one or more baffles between the air-cooled aggregate and the precursor fiber arranged on opposite sides of the precursor fiber (see, for example...). Figure 1 (Precursor fiber 3, baffle 5, and airflow 9). Therefore, by arranging one or more baffles between the precursor fiber and the air-cooled aggregate arranged on the opposite side, i.e., the air-cooled aggregate arranged on the opposite side to the side that provides airflow to the precursor fiber, it is possible to prevent airflow from flowing from the opposite side to the precursor fiber at least a portion along the longitudinal direction of the precursor fiber.

[0052] As used herein, the term "aliphatic polyester" generally refers to polyesters typically synthesized via the polycondensation reaction of aliphatic diols with aliphatic dicarboxylic acids or their anhydrides. As an illustrative example, the aliphatic polyester used herein may contain aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 aliphatic diols. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, the aliphatic diol used in aliphatic polyesters may include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12 Dicarboxylic acids. More preferably, aliphatic dicarboxylic acids are aliphatic C2-C8 dicarboxylic acids, and even more preferably aliphatic C4 dicarboxylic acids. As an illustrative example, aliphatic dicarboxylic acids used in aliphatic polyesters may include oxalic acid, malonic acid, succinic acid, glutaric acid, and adipic acid. Preferably, aliphatic dicarboxylic acids are malonic acid or succinic acid. More preferably, aliphatic dicarboxylic acids are succinic acid. Optionally, when the dicarboxylic acid is aliphatic C2-C8... 12 When dicarboxylic acids are used, aliphatic polyesters may further contain components different from C2-C. 12 Other aliphatic C6-C dicarboxylic acids 20 Dicarboxylic acids. As an illustrative example, an optional aliphatic C6-C... 12 Dicarboxylic acids may include adipic acid, octanoic acid, azelaic acid, sebacic acid, tridecanoic acid, and arachidonic acid. Preferably, optionally, aliphatic C6-C... 12 Dicarboxylic acids may include adipic acid, octanoic acid, azelaic acid, sebacic acid, and tridecanoic acid. Based on 100 mol% of the total aliphatic dicarboxylic acids in the aliphatic polyester, optionally aliphatic C2-C... 12Dicarboxylic acids may be present in aliphatic polyesters at a ratio of 0-10 mol%. Optionally, aliphatic polyesters may further comprise chain extenders and / or branching agents. As illustrative examples, optional chain extenders and / or branching agents may include polyfunctional isocyanates, isocyanurates, oxazolines, carboxylic anhydrides such as maleic anhydride, epoxides (particularly epoxy-containing poly(meth)acrylates), at least ternary alcohols, and at least ternary carboxylic acids. Based on the total amount of 100% by weight of aliphatic dicarboxylic acids and aliphatic diols, optional chain extenders and / or branching agents may be present in a ratio of 0 to 1% by weight of aliphatic polyesters. The term "aliphatic polyester" may also include mixtures of two or more different aliphatic polyesters. The number-average molecular weight (Mn) of the aliphatic polyester can be from 2,500 to 150,000 g / mol, preferably from 5,000 to 100,000 g / mol, more preferably from 7,500 to 75,000 g / mol, even more preferably from 10,000 to 65,000 g / mol, and even more preferably from 12,000 to 60,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic polyester can be from 5,000 to 300,000 g / mol, preferably from 10,000 to 250,000 g / mol, more preferably from 20,000 to 220,000 g / mol, even more preferably from 50,000 to 200,000 g / mol, and even more preferably from 60,000 to 190,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic polyester can be 1 to 6, preferably 1 to 4, more preferably 1.0 to 3.0, even more preferably 1.2 to 2.0, and even more preferably 1.4 to 1.8.

[0053] Illustrative examples of aliphatic polyesters that can be used in this invention may include aliphatic polyesters selected from the following: polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene malonate, polybutylene oxalate, polybutylene malonate, polybutylene co-adipate (PBSA), polybutylene co-azelate (PBSAz), polybutylene co-succinate (PBSBr), and any combination thereof. The aliphatic polyester may preferably be selected from polybutylene succinate (PBS), polybutylene co-adipate (PBSA), polybutylene co-azelate (PBSAz), polybutylene co-succinate (PBSBr), and any combination thereof. In a preferred embodiment, the aliphatic polyester is polybutylene succinate. As used herein, the term "polybutylene succinate" specifically refers to the condensation product of aliphatic dicarboxylic acid succinic acid and aliphatic diol 1,4-butanediol. Aliphatic polyester polybutylene succinate (PBS) and polybutylene co-succinate (PBSA) are commercially available, for example, from Showa Highpolymer. Obtained, and from Mitsubishi The aliphatic polyester, particularly polybutylene succinate (PBS), can be obtained from renewable or fossil resources. Preferably, an aliphatic polyester from a renewable resource is used. More preferably, a bio-based polybutylene succinate (PBS) produced from bio-based succinic acid and 1,4-butanediol can be used, which is, for example, commercially available under the trade name BioPBSTM FZ71 from Mitsubishi Chemicals. Preferably, the aliphatic polyester is biodegradable. In particular, polybutylene succinate (PBS) is a biodegradable aliphatic polyester.

[0054] Preferably, the fiber comprises 30 to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. More preferably, the fiber comprises 35 to 65% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. Even more preferably, the fiber comprises 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester, based on a total of 100% by weight. Even more preferably, the fiber comprises 45 to 55% by weight of aliphatic polyester, based on a total of 100% by weight. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, the fiber comprises 52% by weight of polybutylene succinate, based on a total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate.

[0055] As used herein, the term "aliphatic-aromatic polyester" generally refers to polyesters typically synthesized from aliphatic diols, aliphatic dicarboxylic acids, and aromatic dicarboxylic acids. As an illustrative example, aliphatic-aromatic polyesters may contain aliphatic C2-C... 20 Dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic C2-C 12 Alcohols. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, the aliphatic diol used in aliphatic-aromatic polyesters may include ethylene glycol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12 Dicarboxylic acids. More preferably, aliphatic dicarboxylic acids are aliphatic C4-C. 10Dicarboxylic acids, and even more preferably aliphatic C6 dicarboxylic acids. As illustrative examples, aliphatic dicarboxylic acids used in aliphatic-aromatic polyesters may include glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, tridecanoic acid, octanoic acid, and itaconic acid. Preferably, the aliphatic dicarboxylic acid is adipic acid, azelaic acid, or sebacic acid. More preferably, the aliphatic dicarboxylic acid is adipic acid. Preferably, the aromatic dicarboxylic acid is terephthalic acid. Aromatic dicarboxylic acids, particularly terephthalic acid, may be present in the aliphatic-aromatic polyester in amounts, for example, 30-70 mol%, preferably 40-60 mol%, more preferably 40-55 mol%, each based on a total amount of 100 mol% of the aliphatic dicarboxylic acid and the aromatic dicarboxylic acid. Optionally, the aliphatic polyester may further comprise chain extenders and / or branching agents. As illustrative examples, optional chain extenders may include di- or polyfunctional isocyanates, preferably hexamethylene diisocyanate. As an illustrative example, optional branching agents may include trimethylolpropane, pentaerythritol, and preferably glycerol. Based on the total amount of 100% by weight of aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic diols, optional chain extenders and / or branching agents may be present in the aliphatic polyester at a ratio of 0 to 1% by weight. The term "aliphatic-aromatic polyester" may also include mixtures of two or more different aliphatic-aromatic polyesters. The number-average molecular weight (Mn) of the aliphatic-aromatic polyester may be from 1,000 to 500,000 g / mol, preferably from 5,000 to 300,000 g / mol, more preferably from 5,000 to 100,000 g / mol, even more preferably from 10,000 to 75,000 g / mol, and even more preferably from 15,000 to 50,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic-aromatic polyester can be from 10,000 to 500,000 g / mol, preferably from 20,000 to 400,000 g / mol, more preferably from 30,000 to 300,000 g / mol, and even more preferably from 60,000 to 200,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic-aromatic polyester can be from 1 to 6, preferably from 2 to 4, more preferably from 1.0 to 3.0, even more preferably from 1.2 to 2.0, and even more preferably from 1.4 to 1.8.

[0056] The aliphatic-aromatic polyesters used in this invention may include, but are not limited to, aliphatic-aromatic polyesters selected from polybutylene terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene terephthalate sebacic acid (PBSeT), and any combination thereof. In a preferred embodiment, the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). The term "polybutylene terephthalate" as used herein refers to an aliphatic-aromatic polyester comprising adipic acid (adipic acid), terephthalic acid (arabic dicarboxylic acid), and 1,4-butanediol (aliphatic diol). Aliphatic-aromatic polyesters, particularly polybutylene terephthalate (PBAT), can be obtained from renewable or fossil resources. Preferably, aliphatic-aromatic polyesters from renewable resources are used. Polybutylene terephthalate (PBAT) is, for example, produced by BASF. Sales, for example F Blend C1200 or FBX7011, or by ShowaDenko For sale. Preferably, the aliphatic-aromatic polyester is biodegradable. In particular, polybutylene terephthalate (PBAT) is a biodegradable aliphatic-aromatic polyester.

[0057] Preferably, the fiber comprises 10 to 60% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. More preferably, the fiber comprises 20 to 50% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber comprises 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber comprises 30 to 40% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, the fiber comprises 36% by weight of polybutylene terephthalate (PBAT) based on the total amount of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate.

[0058] As used herein, the term "polyhydroxyalkanoate" generally refers to a polyester derived from a hydroxyalkanoic acid monomer. Polyhydroxyalkanoates can be produced by a variety of microorganisms, including bacterial fermentation of sugars or lipids. Preferably, the hydroxyalkanoic acid is C4-C. 18Hydroxyalkylcarboxylic acids, preferably hydroxyalkylcarboxylic acids, contain 4-18 carbon atoms. More preferably, polyhydroxyalkanoates contain monomer units having the following formula (I):

[0059]

[0060] Where R is a variable with the formula C n H 2n+1 The alkyl group, n is 1-15, preferably an integer of 1-6. In some embodiments, the polyhydroxyalkanoate is a homopolymer. In some preferred embodiments, the polyhydroxyalkanoate is a copolymer. When the polyhydroxyalkanoate is a copolymer, the copolymer may contain two different monomer units of formula (I). The term "polyhydroxyalkanoate" may also include a mixture of two or more different polyhydroxyalkanoates. The weight-average molecular weight (Mw) of the polyhydroxyalkanoate may be in the range of 70,000 to 1,000,000 g / mol, preferably in the range of 100,000 to 1,000,000 g / mol, more preferably in the range of 300,000 to 600,000 g / mol.

[0061] Illustrative examples of polyhydroxyalkanoates that can be used in this invention may include polyhydroxyalkanoates selected from polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, polyhydroxybutyrate-co-hydroxyhexanoate, and any combination thereof. Preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), and any combination thereof. More preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (PHB).

[0062]

[0063] Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)

[0064] and

[0065] Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)

[0066] And any combination thereof. Even more preferably, the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate. In a very preferred embodiment, the polyalkoxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, the molar ratio m:n in the aforementioned structural formula is 95:5 to 85:15, more preferably 90:10 to 88:12. It is preferred to use poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) having a molar ratio of 5-15 mol%, preferably 7-13 mol%, more preferably 10-13 mol% of 3-hydroxyhexanoate, each based on 100 mol% of the total monomers in poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is sold, for example, by P&G or Kaneka. Polyhydroxyalkanoates, especially poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), can be obtained from renewable or fossil resources. Preferably, polyhydroxyalkanoates from renewable resources are used. More preferably, bio-based poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) can be used, which, for example, is available from Kaneka under the trade name AONILEX151A. Preferably, the polyhydroxyalkanoate is biodegradable. In particular, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a biodegradable polyhydroxyalkanoate.

[0067] Preferably, the fiber contains 1 to 25% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. More preferably, the fiber contains 2 to 22% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber contains 3 to 20% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber contains 3 to 18% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber contains 5 to 15% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the fiber contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). If the proportion of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), exceeds 18% by weight, it may become difficult to meet the biodegradability standard of EN 13432 without pre-composting or industrial composting, and this becomes even more difficult when it exceeds 20% by weight. In a preferred embodiment, the fiber contains 12% by weight of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) based on a total amount of 100% by weight of polybutylene succinate, polybutylene adipate terephthalate, and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0068] In a highly preferred embodiment, the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyalkoxyalkylene ester is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Therefore, in a highly preferred embodiment, the fiber comprises polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0069] The ranges of amounts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, the fiber may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the fiber may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the fiber may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxyalkanoates, each based on a total of 100% by weight of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Those skilled in the art will readily select suitable amounts of one or more polymers within the range provided herein, such that the total amount of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates does not exceed 100% by weight. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a highly preferred embodiment, the fiber comprises 52 wt% polybutylene succinate, 36 wt% polybutylene adipate terephthalate, and 12 wt% polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on the total amount of 100 wt% polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0070] Preferably, the fiber is a textile fiber. As used herein, the term "textile fiber" generally refers to a fiber suitable for the production of textiles. As an exemplary and non-limiting example, textile fibers may be suitable for preparing yarns, textiles, or textile surfaces.

[0071] Optionally, the fiber may further comprise at least one additive (or one or more additives). For example, the fiber may comprise at least one additive (or one or more additives) commonly known for use in textile fibers. Optional additives may include, but are not limited to, additives such as flame retardants, matting agents, markers for identification (e.g., fluorescent markers), antimicrobial agents, fillers, and any combination thereof.

[0072] Preferably, the fiber also contains a flame retardant, such as a phosphate. As used herein, the term "phosphate" refers to a substance containing a component selected from [H₂PO₄]. – [HPO4] 2– and [PO4] 3– A salt of an anion. Preferably, the cation is ammonium [NH4]. + Therefore, in a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively or additionally, the flame retardant may be a polyphosphate. A "polyphosphate" is a salt or ester of a polymeric oxyanion formed by tetrahedral PO4 (phosphate) structural units linked together by shared oxygen atoms. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate. Without being bound by theory, this paper believes that the addition of phosphate or polyphosphate flame retardants, particularly diammonium hydrogen phosphate ([NH4]2[HPO4]), can promote partial fusion of adjacent hollow fiber portions during the cooling of precursor fibers under a temperature gradient. This can help to obtain a fiber structure comprising a thicker portion with cavities and a thinner portion with a dense structure, as described herein.

[0073] Based on 100% by weight of the total fiber weight, the fiber may contain 0.01 to 5% by weight of flame retardant. Preferably, based on 100% by weight of the total fiber weight, the fiber contains 0.1 to 4% by weight of flame retardant. More preferably, based on 100% by weight of the total fiber weight, the fiber contains 0.2% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total fiber weight, the fiber contains 0.3% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total fiber weight, the fiber contains 0.3% to 2% by weight of flame retardant. In particular, the above ranges can be applied when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0074] Optionally, the fiber may (also) contain a matting agent. Any matting agent known to those skilled in the art can be used, such as typical matting agents used in fibers. As an illustrative example, the matting agent may be zinc sulfide.

[0075] Optionally, the fiber may also contain a marker suitable for identification. As an illustrative, non-limiting example, the marker suitable for identification may be a fluorescent marker. The fluorescence of the fiber can then be detected by a suitable device and used to identify the fiber. For example, fluorescent markers available from Polysecure, Freiburg im Breisegau, Germany can be used. The marker suitable for identification is typically used only in small amounts and generally does not alter the properties of the fiber. Typically, the amount of the marker suitable for identification in the fiber is in the range of ppb (parts per billion).

[0076] Optionally, the fiber may (also) include an antimicrobial agent. Any antimicrobial agent known to those skilled in the art as suitable for fibers may be used. As an illustrative, non-limiting example, the antimicrobial agent may be zinc encapsulated in polyethylene terephthalate. Such a matting agent, for example, may be commercially available under the trade name SMARTZINC 213PET Hot Melt from SmartPolymer GmbH in Rudolstadt, Germany.

[0077] Optionally, the fibers may (also) include fillers. Any filler known to those skilled in the art suitable for use in fibers may be used, preferably a biodegradable filler. As an illustrative example, the (biodegradable) filler may be lignin or may include lignin.

[0078] Those skilled in the art will readily select the appropriate amount of additives to be included in the fiber. As an illustrative example, the fiber may contain a total of 15% by weight or less of additives based on 100% by weight of the total fiber weight. The fiber may contain a total of 10% by weight or less of additives based on 100% by weight of the total fiber weight. Preferably, the fiber contains a total of 7% by weight or less of additives based on 100% by weight of the total fiber weight. More preferably, the fiber contains a total of 5% by weight or less of additives based on 100% by weight of the total fiber weight. Even more preferably, the fiber contains a total of 4% by weight or less of additives based on 100% by weight of the total fiber weight. Even more preferably, the fiber contains a total of 3 to 4% by weight of additives based on 100% by weight of the total fiber weight. Preferably, the fiber contains a total of 7% by weight or less, more preferably 3 to 4% by weight of additives, each based on 100% by weight of the total fiber weight, in order to achieve fiber stiffness suitable for use in textile fibers.

[0079] There are no particular limitations on fiber fineness. For example, any fiber fineness commonly used in the textile industry can be used. As an illustrative example, the fiber fineness can be from 0.5 to 8 denier. Preferably, the fiber fineness is from 0.8 to 6 denier. More preferably, the fiber fineness is from 0.9 to 3 denier. Even more preferably, the fiber fineness is from 1.0 to 2 denier. Still more preferably, the fiber fineness is from 1.0 to 1.5 denier. Even more preferably, the fiber fineness is from 1.1 to 1.2 denier.

[0080] The fiber can be a short fiber. As used herein, the term "short fiber" generally refers to a fiber of discrete length. There is no particular limitation on the length of the short fiber. For example, any stable length commonly used in the textile industry can be used. Thus, as an illustrative example, the fiber may have a short fiber length of 2 to 80 mm. Preferably, the fiber has a short fiber length of 5 to 70 mm. More preferably, the fiber has a short fiber length of 10 to 60 mm. Even more preferably, the fiber has a short fiber length of 15 to 50 mm. Even more preferably, the fiber has a short fiber length of 20 to 40 mm. Even more preferably, the fiber has a short fiber length of 22 to 35 mm. Even more preferably, the fiber has a short fiber length of 25 to 32 mm. The term "short fiber length" generally refers to the average length of the fibers in the sample.

[0081] Fibers can be filaments. The terms "filament" or "filament fiber" generally refer to fibers that are virtually of unlimited length. Therefore, the terms "filament" or "filament fiber" generally refer to continuous fibers.

[0082] Preferably, the fiber is biodegradable. More preferably, the fiber is biodegradable according to EN 13432. Therefore, according to EN 13432, a fiber can be considered biodegradable when it has at least 90% of the DIN EN 13432 biodegradation percentage after a specified period of time. A general effect of biodegradability is the breakdown of the fiber within an appropriate and verifiable time interval. Degradation can be achieved by enzymatic, hydrolytic, oxidative, and / or by the action of electromagnetic radiation such as UV radiation, and may be primarily due to the action of microorganisms such as bacteria, yeast, fungi, and algae. Biodegradability can be quantified, for example, by mixing the fiber with compost and storing it for a certain period of time. For example, during composting, CO2-free air may flow through the maturing compost, and the maturing compost undergoes a defined temperature program. Biodegradability can be defined, for example, as the percentage degree of biodegradation by the ratio of the net CO2 released by the sample (after deducting the CO2 released by compost without the sample) to the maximum amount of CO2 that the sample can release (calculated from the carbon content of the sample). Biodegradable fibers typically show clear signs of degradation, such as fungal growth, cracking, and pore formation, just days after composting. Other methods for determining biodegradability are described, for example, in ASTM D 5338 and ASTM D 6400.

[0083] Preferably, the thicker and thinner portions of the fiber are arranged in an alternating pattern along the longitudinal direction of the fiber. The lengths of the thicker and thinner portions along the longitudinal direction of the fiber can be irregular.

[0084] In the fiber, the extension of the cavity in the longitudinal direction of the fiber can be greater than the extension of the cavity in the direction perpendicular to the longitudinal direction of the fiber. The cavity can have an irregular circumference (e.g., as shown in the image). Figure 5E (As shown). In particular, the circumference can be irregular in a plane conceived in the direction perpendicular to the longitudinal direction of the fiber.

[0085] Preferably, the fiber is a crimped fiber.

[0086] The present invention also relates to hollow fibers made from mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. As used herein and known in the art, the term "hollow fiber" generally refers to a fiber having one or more, particularly a continuous cavity in its cross-section (e.g., see...). Figure 8 (An exemplary example of a hollow fiber 21 having continuous cavities 23). One or more cavities may be filled, for example, with air. Such a hollow fiber may be prepared by any method known in the art suitable for preparing hollow fibers.

[0087] As an illustrative example, hollow fibers can be obtained by or be obtained by methods including spinning a melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate through a hollow fiber spinning nozzle to obtain precursor fibers. As an illustrative example, as described above, the aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate can be mixed in an unmelted state, for example, by mixing polymer particles, optionally with one or more other additives, and the mixture can be heated to the melting point of the polymer or above. As an illustrative example, mixing and heating can be carried out in an extruder. The melt is then passed through a hollow fiber spinning nozzle. As an illustrative example, an extruder can be used to pass the melt through the hollow fiber spinning nozzle. Any hollow fiber spinning nozzle commonly known in the art can be used, such as the hollow fiber spinning nozzle described in EP2112256, the entire contents of which are incorporated herein by reference. Spinning a melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate through a hollow fiber spinning nozzle yields hot precursor fibers. However, after passing through the spinning nozzle, the precursor fibers are cooled using conventional methods to obtain conventional hollow fibers. For example, cooling using conventional methods can be envisioned to achieve cooling of the precursor fibers throughout the fiber with a substantially uniform temperature distribution. Therefore, the temperature gradient described above can be largely avoided. A substantially uniform temperature distribution can be produced by one or more temperature control elements. As an illustrative example, a uniform temperature distribution can be produced by arranging and / or operating temperature control elements within or near the spinning equipment in a suitable manner. The temperature control elements can be heating and / or cooling elements (e.g., air-cooled aggregate) that can actively or passively provide heating or cooling effects to the precursor fibers. With such temperature control elements, each side / surface area of ​​the precursor fiber can be cooled such that the temperature distribution on each side / surface area is substantially uniform. Those skilled in the art will readily arrange one or more temperature control elements in a suitable manner to achieve a uniform temperature distribution throughout the precursor fiber. For example, air cooling can be used to cool the precursor fibers. Preferably, air cooling can be achieved by using air-cooled aggregate arranged on both sides of the precursor fiber, providing airflow from both sides to the precursor fiber in a direction substantially perpendicular to the longitudinal direction of the precursor fiber. As an illustrative example only, by removing... Figure 1 The baffle 5 between the precursor fiber 3 and the airflow 9 shown can provide airflow to the precursor fiber from both sides.

[0088] Hollow fibers may be further defined as described herein with respect to any fiber. Thus, as an exemplary example, hollow fibers may be further defined herein with respect to any fiber with respect to aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates, the ratio of polymers and / or at least one additive.

[0089] Optionally, any fiber described herein may be post-processed, for example using a fiber post-processing production line. Post-processing may include steps typically used to process fibers, such as reeding, introducing a structure, impregnation, drawing, stretching, steaming, recovery, crimping, drying, and / or short fiber cutting.

[0090] This invention also relates to yarns comprising the fibers as described herein. Any type of yarn can be considered. By way of non-illustrative example, the yarn can be a fine yarn, carded or combed yarn, knitted yarn, free-end yarn, novel yarn, filament yarn, or textured yarn. The yarn can be prepared from the fibers described herein by any method suitable for yarn preparation. Methods for yarn preparation are generally known and readily chosen by those skilled in the art.

[0091] The present invention also relates to textile surfaces comprising the fibers described herein. The present invention further relates to textile surfaces comprising yarns comprising the fibers as described herein. As illustrative and non-limiting examples, textile surfaces may be selected from woven fabrics, knitted fabrics, and nonwoven fabrics. Fibers or yarns comprising fibers may also be used to produce wool.

[0092] The present invention also relates to textiles comprising the fibers described herein. The present invention further relates to textiles comprising yarns comprising the fibers described herein. Textiles can be clothing. As an illustrative, non-limiting example, clothing can be selected from shirts, polo shirts, trousers, jackets, underwear, socks, coats, shoes, and shoelaces. In particular, clothing can be shirts or jerseys, preferably shirts. Textiles can be home textiles. As an illustrative, non-limiting example, home textiles can be selected from curtains, carpets, blankets, sheets, comforters, comforter covers, mattresses, mattress covers, and towels.

[0093] The present invention also relates to a method for preparing fibers according to the present invention, comprising:

[0094] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0095] - The precursor fibers are cooled under a temperature gradient to obtain the fibers. The fibers may be further defined as described herein.

[0096] Preferably, a temperature gradient is generated by cooling the precursor fibers from one side.

[0097] Preferably, cooling is achieved by air cooling.

[0098] Preferably, the melt comprises 30 to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. More preferably, the melt comprises 35 to 65% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. Even more preferably, the melt comprises 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester, based on a total of 100% by weight. Even more preferably, the melt comprises 45 to 55% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, the melt contains 52% by weight of polybutylene succinate, based on a total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate.

[0099] Preferably, the melt comprises 10 to 60% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. More preferably, the melt comprises 20 to 50% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the melt comprises 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the melt comprises 30 to 40% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, the melt contains 36% by weight of polybutylene terephthalate (PBAT) based on the total amount of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate.

[0100] Preferably, the melt contains 1 to 25% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. More preferably, the melt contains 2 to 22% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the melt contains 3 to 20% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the melt contains 3 to 18% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the melt contains 5 to 15% by weight of polyhydroxyalkanoate based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the melt contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0101] The ranges of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, the melt may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the melt may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the melt may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxybutyrate, each based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Those skilled in the art will readily select suitable amounts of one or more polymers within the ranges provided herein, such that they do not exceed 100% by weight of the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the melt comprises 52 wt% polybutylene succinate, 36 wt% polybutylene adipate terephthalate, and 12 wt% polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on the total amount of 100 wt% polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0102] Optionally, the melt may further comprise at least one additive. For example, the melt may comprise at least one additive commonly known for use in textile fibers. Optional additives may include, but are not limited to, additives selected from flame retardants, matting agents, identification markers (e.g., fluorescent markers), antimicrobial agents, fillers, and any combination thereof.

[0103] Preferably, the melt further comprises a flame retardant. More preferably, the flame retardant is a phosphate ester. In a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively or additionally, the flame retardant may be a polyphosphate. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0104] Based on 100% by weight of the total melt weight, the melt may contain 0.01 to 5% by weight of flame retardant. Preferably, based on 100% by weight of the total melt weight, the melt contains 0.1 to 4% by weight of flame retardant. More preferably, based on 100% by weight of the total melt weight, the melt contains 0.2% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total melt weight, the melt contains 0.3% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total melt weight, the melt contains 0.3% to 2% by weight of flame retardant. In particular, when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]), the above ranges can be applied.

[0105] Those skilled in the art will readily select the appropriate amount of additives contained in the melt. As an illustrative example, the melt may contain a total of 15% by weight or less of additives based on 100% by weight of the total melt weight. The melt may contain a total of 10% by weight or less of additives based on 100% by weight of the total melt weight. Preferably, the melt contains a total of 7% by weight or less of additives based on 100% by weight of the total melt weight. More preferably, the melt contains a total of 5% by weight or less of additives based on 100% by weight of the total melt weight. Even more preferably, the melt contains a total of 4% by weight or less of additives based on 100% by weight of the total melt weight. Even more preferably, the melt contains a total of 3 to 4% by weight of additives based on 100% by weight of the total melt weight. Preferably, the melt contains a total of 7% by weight or less, more preferably 3-4% by weight of additives, each based on 100% by weight of the total melt weight, to obtain stiffness suitable for use in textile fibers.

[0106] The fiber can be prepared as short fiber.

[0107] The fiber can be prepared into filaments.

[0108] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined herein.

[0109] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

[0110] The present invention also relates to mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Such mixtures can be used, for example, to prepare the fibers of the present invention.

[0111] The aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates contained in the mixture may be further defined as described herein, particularly as defined herein for any fiber. In a highly preferred embodiment, the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyalkoxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Therefore, the present invention also relates to a mixture comprising polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0112] In some embodiments, the mixture is substantially composed of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. In some embodiments, the mixture is substantially composed of polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In some embodiments, the mixture is composed of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. In some embodiments, the mixture is composed of polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0113] In the mixture, aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates may be present in particulate form. Illustrative examples of particles that can be used in the mixture may be selected from granules, pellets, extrudates, beads, balls, and any combination thereof. Preferably, the aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are in particulate form. In a very preferred embodiment, the mixture comprises polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) in particulate form. The invention also relates to particles comprising polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). To prepare fibers, the mixture containing polymer particles can be heated above the melting point of the polymer. In some embodiments, the mixture may therefore be present in the form of a melt. As described herein, the melt can be spun.

[0114] Preferably, the mixture comprises 30 to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. More preferably, the mixture comprises 35 to 65% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. Even more preferably, the mixture comprises 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester, based on a total of 100% by weight. Even more preferably, the mixture comprises 45 to 55% by weight of aliphatic polyester, based on a total of 100% by weight. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, the mixture comprises 52% by weight of polybutylene succinate, based on the total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate.

[0115] Preferably, the mixture comprises 10 to 60% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. More preferably, the mixture comprises 20 to 50% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the mixture comprises 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the mixture comprises 30 to 40% by weight of aliphatic-aromatic polyester based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, the mixture contains 36% by weight of polybutylene terephthalate (PBAT) based on the total amount of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate.

[0116] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 2 to 22% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 5 to 15% by weight of polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the melt contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0117] The ranges of amounts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, the melt may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the melt may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the melt may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxybutyrate, each based on a total of 100% by weight of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Those skilled in the art will readily select suitable amounts of one or more polymers within the ranges provided herein, such that the total amount of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates does not exceed 100% by weight. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the mixture comprises 52 wt% polybutylene succinate, 36 wt% polybutylene adipate, and 12 wt% polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on the total amount of 100 wt% polybutylene succinate, polybutylene adipate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0118] Optionally, the mixture may further comprise at least one additive. For example, the mixture may comprise at least one additive commonly known for use in textile fibers. Optional additives may include, but are not limited to, additives selected from flame retardants, matting agents, identification markers (e.g., fluorescent markers), antimicrobial agents, fillers, and any combination thereof.

[0119] Preferably, the mixture further comprises a flame retardant. More preferably, the flame retardant is a phosphate ester. In a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively or additionally, the flame retardant may be a polyphosphate. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0120] Based on 100% by weight of the total melt weight, the mixture may contain 0.01 to 5% by weight of flame retardant. Preferably, based on 100% by weight of the total mixture weight, the mixture contains 0.1 to 4% by weight of flame retardant. More preferably, based on 100% by weight of the total mixture weight, the mixture contains 0.2% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total mixture weight, the mixture contains 0.3% to 3% by weight of flame retardant. Even more preferably, based on 100% by weight of the total mixture weight, the mixture contains 0.3% to 2% by weight of flame retardant. In particular, the above ranges can be applied when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0121] Those skilled in the art will readily select the appropriate amount of additives to be included in the mixture. As an illustrative example, the mixture may contain 15% by weight or less of additives based on 100% by weight of the total melt weight. The mixture may contain 10% by weight or less of additives based on 100% by weight of the total melt weight. Preferably, the mixture contains 7% by weight or less of additives based on 100% by weight of the total mixture weight. More preferably, the mixture contains 5% by weight or less of additives based on 100% by weight of the total mixture weight. Even more preferably, the mixture contains 4% by weight or less of additives based on 100% by weight of the total mixture weight. Even more preferably, the mixture contains 3 to 4% by weight of additives based on 100% by weight of the total mixture weight. Preferably, the mixture contains 7% by weight or less, more preferably 3-4% by weight of additives, each based on 100% by weight of the total mixture weight, to obtain stiffness suitable for use in textile fibers.

[0122] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers, wherein the fibers are as defined herein.

[0123] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

[0124] It should be noted that, as used herein, the singular forms “a,” “an,” and “the” include plural references unless the context clearly indicates otherwise. Thus, for example, reference to “a reagent” includes one or more such different reagents, and reference to “the method” includes reference to equivalent steps and methods known to those skilled in the art, which may be modified or substituted for the methods described herein.

[0125] Unless otherwise stated, the term "at least" preceding a series of elements should be understood to refer to each element in that series. Those skilled in the art will recognize or be able to determine many equivalent embodiments of the specific implementations of the invention described herein using no more than conventional experiments. These equivalent embodiments are also included in this invention.

[0126] The term “and / or” as used herein includes the meaning of “and,” “or,” and “all or any other combination of elements connected by the term.”

[0127] The terms "less than" or "greater than" do not include specific numbers. For example, "less than 20" means less than the indicated number. Similarly, "greater than" means greater than the indicated number; for example, "greater than 80%" means greater than 80% of the indicated number.

[0128] Throughout this specification and the following claims, unless the context otherwise requires, the word “comprising” and its variations such as “including” and “containing” shall be construed as implying the inclusion of the stated whole or step or group of whole or steps, but not excluding any other whole or step or group of whole or steps. When used herein, the term “comprising” may be replaced by the terms “containing” or “including”, or sometimes by the term “having” when used herein.

[0129] When used herein, “composed of” excludes any element, step, or component not specified in the elements of the claim, and when used herein, “substantially composed of” does not exclude material or steps that do not substantially affect the essential and novel features of the claim. In each case herein, any one of the terms “comprising,” “substantially composed of,” and “composed of” may be replaced by any of the other two terms.

[0130] The term "including" means "including but not limited to". "Including" and "including but not limited to" are used interchangeably.

[0131] When used herein, the term “about” should be understood to mean that a variation may exist in the corresponding value or range (such as pH, concentration, percentage, molar concentration, time, etc.), which may be up to 5% or up to 10% of a given value. For example, if a formulation contains about 5 mg / ml of the compound, this is understood to mean that the formulation may have 4.5 to 5.5 mg / ml of the compound.

[0132] It should be understood that the present invention is not limited to the specific methods, schemes, materials, reagents, and substances described herein, and therefore variations are possible. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the invention, which is defined only by the claims.

[0133] All publications (including all patents, patent applications, scientific publications, specifications, etc.) cited throughout this specification are incorporated herein by reference in their entirety, whether above or below. Nothing herein should be construed as an admission that the invention is not entitled to any prior art based on such disclosures. To a certain extent, where any material incorporated by reference contradicts or is inconsistent with this specification, this specification supersedes any such material.

[0134] All references and patent documents cited herein are incorporated herein by reference in their entirety.

[0135] The following examples will provide a better understanding of the invention and its advantages; these examples are provided for illustrative purposes only. These examples do not limit the scope of the invention in any way. Example

[0136] Example 1: Preparation of fibers according to an embodiment of the present invention

[0137] According to an embodiment of the present invention, fibers are prepared using the following components (polymer I, polymer II, polymer III, and additive masterbatch):

[0138] Polymer I Polybutylene succinate (PBS, Mitsubishi Chemicals Bio PBS FZ71, bio-based)

[0139] Polymer II Polybutylene adipate terephthalate (PBAT, BASF ECOFLEX PBAT)

[0140] Polymer III Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PBHB, KANEKA AONILEX151A, bio-based)

[0141] Masterbatch: The masterbatch includes the amounts of additives shown in Table 1 below.

[0142] Table 1

[0143]

[0144]

[0145] Fibers according to embodiments of the invention are prepared using a FournéPilot melt spinning test apparatus (Fourné Maschinenbau GmbH, Alfter-Impekween, Germany), which has an improved module for side flow allowance for masterbatch additives, a hollow fiber spinning nozzle (e.g., a hollow fiber spinning nozzle as described in EP2112256B1 can be used), and a fiber post-processing line; the FournéPilot melt spinning test apparatus is shown in Figure 2B In the fiber post-processing line, further external treatment is carried out using steps including reed, inlet structure, immersion bath, drafting system I, stretching bath, drafting system II, steaming, drafting system III, regeneration roller, crimping, drying, and shredding. Alternatively, other melt spinning equipment may be used. Figure 2A This shows an example of another melt spinning device.

[0146] Polymer I (15,600 g, polybutylene succinate (PBS)), polymer II (10,800 g, polybutylene adipate terephthalate (PBAT)), and polymer III (3,600 g, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)) were added as granules to a melt spinning tester. Additionally, 1,650 kg of powdered masterbatch (additive) was added to a side-flow permissible module via a simple screw feeder. The moisture content was approximately 0.1% by weight. Polymers I, II, and III, as well as the masterbatch (additive), were dried in a vacuum drying oven at 60°C for 24 hours prior to addition.

[0147] Use the following process parameters:

[0148] Flow rate: 2.5 kg / h to 5.12 m / min of filament bundle;

[0149] Processing temperature: 250℃;

[0150] Distance between hollow fiber spinning nozzle and guide roller: 200 cm;

[0151] Lead-out roller: 85℃, 800m / min;

[0152] Guide roller 1: 80℃, 980m / min;

[0153] Guide roller 2: 80℃, 1350m / min;

[0154] Air-cooled aggregate is opened on one side of the precursor fiber to provide airflow to the precursor fiber from said side; and

[0155] By providing a baffle between the air-cooled aggregate and the precursor fibers, air cooling is shut off on the opposite side of the precursor fibers, preventing air from flowing from one side to the other. Therefore, the precursor fibers are cooled under a temperature gradient.

[0156] Figure 1 A melt spinning apparatus and a method for preparing the fiber are schematically described. Figure 1 The melt spinning apparatus includes a hollow fiber spinning nozzle 1. Using an extruder, a melt containing three polymers is spun through the hollow fiber spinning nozzle 1 to obtain a hot precursor fiber 3. In this embodiment, the processing temperature of the melt is 250°C. An airflow 7 is provided from the left side onto the precursor fiber 3 in a direction substantially perpendicular to the longitudinal direction of the precursor fiber 3 to cool the precursor fiber 3. The airflow 7 can be provided by air-cooled aggregate, which is schematically represented by a snowflake on the left. In this example, the air used for the airflow 7 has an ambient temperature (approximately 20°C). An airflow 9 is provided from the right side. The airflow 9 can also be provided by air-cooled aggregate, which is schematically represented by a snowflake on the right. A baffle 5 is located between the airflow 9 and the precursor fiber 3. Therefore, the baffle 5 prevents the airflow 9 from reaching the precursor fiber 3 from the right side, passing over a portion of the precursor fiber 3 covered by the baffle 5. Thus, only the airflow 7 from the left side reaches the precursor fiber 3. As a result, the precursor fiber 3 has a lower temperature on the left side where the airflow 7 impacts the precursor fiber 3 than on the right side where the airflow 9 is blocked by the baffle 5. Therefore, the precursor fiber 3 is cooled under the temperature gradient. After cooling under the temperature gradient, fiber 11 is obtained, and then fiber 11 is wound with guide roller 13.

[0157] Alternatively, instead of using a baffle, one of the two air-cooled aggregates in the melt spinning equipment can be shut off, so that airflow is once again supplied to the precursor fiber 3 only from one side.

[0158] This embodiment uses the FournéPilot melt spinning test apparatus (Fourné Maschinenbau GmbH, Alfter-Impekweat, Germany), which... Figure 2B As described in the text. Alternatively, any other suitable melt spinning apparatus can be used, such as... Figure 2A The larger melt spinning apparatus shown is illustrated. Figure 2A and Figure 2B In the middle, ovals are drawn to mark the air-cooled aggregate equipped with grids.

[0159] Figure 3 An extended scheme for preparing fibers and further processing fibers through post-treatment is shown according to embodiments of the present invention. For example... Figure 3 As shown, fibers can be processed, cut, and compressed into packages.

[0160] Figure 4This displays the fibers commonly used in textile production. From left to right, they are shown: coarse wool, fine wool, alpaca wool, cashmere, silk, linen, cotton, and polyester.

[0161] Figure 5A , 5B 5C, 5D, 5E and 5F illustrate fibers according to embodiments of the present invention, which are prepared by cooling precursor fibers under a temperature gradient, for example as described in Example 1. Figure 5A A schematic diagram of a fiber according to an embodiment of the present invention is shown. Fiber 11 includes a thicker portion 15 and a thinner portion 17. The thicker portion includes a cavity 19. Figure 5B An electron micrograph of a fiber according to an embodiment of the present invention is shown. Thicker and thinner portions can be distinguished. Figure 5C An electron micrograph of a fiber according to an embodiment of the invention is shown. The micrograph shows a thinner portion of the fiber arranged between two thicker portions. The fiber has a substantially smooth outer surface. Figure 5D An electron micrograph showing a cross-section of a fiber according to an embodiment of the present invention. The cavity is visible. Figure 5E Further electron micrographs showing the cross-section of a fiber according to an embodiment of the invention. The three micrographs in the top figure and the middle micrograph in the bottom figure show the cross-section of the thicker portion of the fiber. The cavity is visible. The cavity may have an irregular circumference facing the outer wall of the fiber. The outer wall includes holes. The left and right micrographs in the bottom figure show the cross-section of the thinner portion of the fiber. Compared to the cavity in the thicker portion, the thinner portion has a compact or dense structure. It can be seen that the thinner portion has holes. Figure 5F An electron micrograph showing a cross-section of the outer wall of the fiber cavity according to an embodiment of the present invention. It can also be seen that the outer wall has a porous structure.

[0162] Figure 8 A schematic diagram of a hollow fiber 21 according to an embodiment of the present invention is shown. The hollow fiber 21 has continuous cavities 23, and this hollow fiber can be prepared using conventional melt spinning methods without applying a temperature gradient.

[0163] Example 2: Antimony Content Test

[0164] The antimony content of fibers obtained by cooling under a temperature gradient was tested in the laboratory of Dr. Matt, Schaan, and Liechtenstein, for example, in Example 1. In principle, the toxic element antimony can exist as a residue of the catalyst used in the polymer production process.

[0165] The antimony content was tested as follows:

[0166] The fiber from Example 1 was inserted into water and (a) heated to the boiling point of the water; (b) stored in water for 8 weeks; and (c) further stored in a glass containing water and air for 4 weeks (sealed, 1 / 3 air, 2 / 3 water).

[0167] Antimony was not detected in the fibers and water (antimony S6 < 0.1 mg / kg ICP-MS). Therefore, this test shows that fibers can be prepared without the use of toxic antimony.

[0168] Example 3: Moisture Absorption Test

[0169] In this embodiment, the hygroscopicity of the fibers according to embodiments of the present invention, such as the fibers obtained by cooling under a temperature gradient in Example 1, was compared with commercially available cotton fibers and two other commercially available synthetic fibers, namely polyester (PES) fibers and polybutylene succinate (PBS) fibers. Furthermore, the drying properties of the fibers were also tested. The fibers and their sources are described in Table 2 below:

[0170] Table 2

[0171]

[0172]

[0173] The device for moisture absorption testing, such as Figure 6A As shown. Four fiber balls (from left to right: cotton, fiber according to an embodiment of the invention (obtained by cooling under a temperature gradient), polyester (PES), polybutylene succinate (PBS)), each about 4 cm long, were attached to a rod with clamps to prepare fiber balls such that they have approximately the same length and volume during visual inspection.

[0174] Figure 6B The test setup immediately prior to the test is shown. Four petri dishes were filled with water and approximately 3% by volume of blue ink to provide blue water, which is also referred to herein as “colored water,” “liquid,” or “colored liquid.” The test was conducted as follows: four fiber balls were slightly moistened with a water sprayer to provide them with equal moisture content before the start of the test. The weight of the fiber balls was measured before immersion in the colored liquid. The weights of the fiber balls are given in Table 3 below. A rod with four fiber balls (from left to right: cotton, fiber according to an embodiment of the invention (obtained by cooling under a temperature gradient), polyester (PES), polybutylene succinate (PBS)) was then suspended such that the four fiber balls were simultaneously immersed in the colored liquid for approximately 1 cm. The time measurement began when the fiber balls were immersed in the liquid.

[0175] Use a camera to record the coloring process over time. Figure 6C The test is shown approximately 13 seconds after the fiber ball was immersed in the liquid. Figure 6D The results show that after immersing the fiber balls in the liquid for approximately 3.5 minutes, the dyeing of the cotton fibers (first from the left) and the fibers according to an embodiment of the invention (obtained using cooling under a temperature gradient, second from the left) is visible. Typically, the dyeing of the cotton fibers and the fibers according to an embodiment of the invention can be observed 2 minutes after immersing the fiber balls in the colored liquid. Figure 6E The results showed that after immersing the fiber balls in the liquid for 6 minutes, the portions of the cotton fibers and the fibers according to an embodiment of the invention (obtained using cooling under a temperature gradient) that were in direct contact with the liquid swelled significantly. Notably, the PBS fiber ball (fourth from the left) also showed very slight staining in the middle; however, this was not visible when the test was repeated. Figure 6F The test was stopped immediately after immersing the fiber balls in the liquid for 15 minutes. After 15 minutes in the blue liquid, the fiber balls were simultaneously removed from the liquid. The fiber balls were suspended on a petri dish for 1 minute to drain. The fiber balls were compared visually and weighed (in this respect, the weight of the fiber balls was determined before immersion in the colored water and compared after fiber removal and after draining). The fiber balls were then dried at 40°C for 10 minutes and weighed again. Figure 7 The fibrous balls were dried in a petri dish at 40°C for 10 minutes. The results are shown in Table 3.

[0176]

[0177] like Figure 6F As shown, after immersion in the blue liquid for 15 minutes, the fiber ball according to an embodiment of the invention (obtained by cooling under a temperature gradient, second from the left) substantially retains its shape. In the fiber ball according to an embodiment of the invention (second from the left), the liquid has moved upwards to a higher level than in the cotton fiber ball (first from the left). At the bottom of the cotton fiber ball, clumping caused by expansion can be observed.

[0178] According to embodiments of the invention, the fibers (obtained using cooling under a temperature gradient) and cotton absorbed most of the liquid, see Table 3, "Weight difference relative to dry fiber balls after 15 minutes in liquid". After the draining stage, the fibers according to embodiments of the invention retained more liquid than cotton, both in absolute and percentage terms, see Table 3, "Weight difference relative to dry fiber balls after 15 minutes in liquid and approximately 1 minute of draining". According to embodiments of the invention, the drying time required for the fibers is significantly shorter than that for cotton, as can be seen from Table 3, see "Weight difference after 10 minutes of drying at 40°C". Unlike the other two synthetic fibers (PES and PBS), the fibers according to embodiments of the invention are capable of absorbing liquid.

[0179] In summary, the fibers according to embodiments of the present invention (obtained by cooling under a temperature gradient) have slightly better moisture absorption than cotton. Furthermore, the fibers according to embodiments of the present invention exhibit significantly better performance during drying. Therefore, the fibers according to embodiments of the present invention can be used to create moisture-absorbing surfaces and allow them to be dried again with less energy than cotton.

[0180] Example 4: Further features of the fiber according to an embodiment of the present invention

[0181] Further characteristics of fibers according to embodiments of the invention (such as those obtained by cooling under a temperature gradient as used in Example 1) compared to known commercially available fibers used in the production of textiles are listed in Table 4 below.

[0182]

[0183]

[0184] As can be seen from Table 4, the fibers according to embodiments of the present invention (obtained by cooling under a temperature gradient) can be prepared with flame retardants, are hydrophilic, can be prepared without antimony, are biodegradable according to EN 13432, are stain-resistant, wrinkle-resistant, and can be prepared using a certain proportion of renewable raw materials. The preparation of fibers according to embodiments of the present invention requires much less water consumption than cotton. Furthermore, according to embodiments of the present invention, the area required to prepare 1 ton (1000 kg) of fiber is also much less than that required for cotton. Therefore, from an ecological point of view, the fibers according to embodiments of the present invention are advantageous compared to cotton.

[0185] Example 5: Apparel comprising fibers according to the embodiments of the present invention

[0186] Fibers according to embodiments of the invention (such as those obtained by cooling under a temperature gradient in Example 1), particularly yarns made from these fibers, have been used in the production of shirts. Various views of the shirts are shown in... Figure 9A , 9B As shown in 9C. The shirt contains about 40% fiber according to an embodiment of the invention and about 60% cotton.

[0187] The invention is further characterized by the following items:

[0188] 1. A fiber, which can be obtained by means of or through a method comprising the following steps:

[0189] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0190] - The precursor fibers are cooled under a temperature gradient to obtain fibers.

[0191] 2. The fiber according to Item 1, wherein the temperature gradient is generated by one or more temperature control elements.

[0192] 3. The fiber according to item 2, wherein the one or more temperature control elements are arranged such that the temperature gradient is generated in a direction substantially perpendicular to the longitudinal direction of the precursor fiber.

[0193] 4. The fiber according to item 2 or 3, wherein the one or more temperature control elements are arranged such that the temperature gradient is generated in a direction substantially parallel to the cross-section of the precursor fiber.

[0194] 5. The fiber according to any one of items 2 to 4, wherein the one or more temperature control elements are arranged such that the temperature on the outer surface of the precursor fiber is lower than the temperature on the opposite outer surface.

[0195] 6. The fiber according to any one of items 2 to 5, wherein the one or more temperature control elements are arranged such that the precursor fiber is cooled from one side.

[0196] 7. The fiber according to item 6, wherein the cooling is achieved by air cooling.

[0197] 8. The fiber according to item 6 or 7, wherein the air cooling is achieved by providing an airflow from one side onto the precursor fiber in a direction substantially perpendicular to the longitudinal direction of the precursor fiber using air-cooled aggregate disposed on one side of the precursor fiber.

[0198] 9. The fiber according to item 8, wherein airflow from the opposite side to one side is prevented by cutting the air-cooled aggregate arranged on the opposite side of the precursor fiber.

[0199] 10. The fiber according to item 8, wherein airflow from the opposite side to one side is prevented by arranging one or more baffles between air-cooled aggregates arranged on opposite sides of the precursor fiber, thereby preventing airflow from the opposite side to the precursor fiber at least a portion along the longitudinal direction of the precursor fiber.

[0200] 11. The fiber according to any one of the preceding items, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

[0201] 12. The fiber according to any one of the preceding items, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene succinate, polybutylene oxalate, polybutylene malonate, polybutylene succinate-co-butylene adipate (PBSA), polybutylene succinate-co-butylene azelaate (PBSAz), polybutylene succinate-co-butylene brassinate (PBSBr), and any combination thereof.

[0202] 13. The fiber according to any one of the preceding items, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polybutylene succinate-co-adipate (PBSA), polybutylene succinate-co-azelate (PBSAz), polybutylene succinate-co-brasinate (PBSBr), and any combination thereof.

[0203] 14. The fiber according to any one of the preceding items, wherein the aliphatic polyester is polybutylene succinate (PBS).

[0204] 15. The fiber according to any one of the preceding items, wherein the fiber comprises 30% to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate based on a combined amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0205] 16. The fiber according to any one of the preceding items, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol.

[0206] 17. The fiber according to any one of the preceding items, wherein the aliphatic-aromatic polyester is selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacate terephthalate (PBSeT), and any combination thereof.

[0207] 18. The fiber according to any one of the preceding items, wherein the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT).

[0208] 19. The fiber according to any one of the preceding items, wherein the fiber comprises 10% to 60% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate based on the total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0209] 20. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkylcarboxylic acids.

[0210] 21. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is selected from polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, polyhydroxybutyrate-co-hydroxyhexanoate, and any combination thereof.

[0211] 22. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), and any combination thereof.

[0212] 23. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0213] 24. The fiber according to any one of the preceding items, wherein the fiber comprises 1 to 25% by weight of polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0214] 25. The fiber according to any one of the preceding items, wherein, based on a total amount of 100% by weight of aliphatic polyester, aromatic-aliphatic polyester and polyhydroxyalkanoate, the fiber comprises 42% to 62% by weight of aliphatic polyester, 26% to 46% by weight of aromatic-aliphatic polyester and 2% to 22% by weight of polyhydroxyalkanoate.

[0215] 25a. The fiber according to any one of the preceding items, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate).

[0216] (PHBH).

[0217] 26. The fiber according to any one of the preceding items, wherein the fiber is a textile fiber.

[0218] 27. The fiber according to any one of the preceding items, wherein the fiber further comprises at least one additive.

[0219] 28. The fiber according to item 27, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, fillers, and any combination thereof.

[0220] 29. The fiber according to item 28, wherein the additive is a flame retardant.

[0221] 30. The fiber according to item 29, wherein the flame retardant is a phosphate selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and any combination thereof.

[0222] 31. The fiber according to item 30, wherein the phosphate is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0223] 32. The fiber according to any one of items 27 to 31, wherein, based on 100% by weight of the total fiber weight, the fiber contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of flame retardant.

[0224] 33. The fiber according to any one of items 27 to 32, wherein the additive is a matting agent.

[0225] 34. The fiber according to item 33, wherein the matting agent is zinc sulfide.

[0226] 35. The fiber according to any one of items 27 to 34, wherein the additive is a fluorescent marker.

[0227] 36. The fiber according to any one of items 27 to 35, wherein the additive is an antimicrobial agent.

[0228] 37. The fiber according to item 36, wherein the antimicrobial agent is zinc encapsulated in polyethylene terephthalate.

[0229] 38. The fiber according to any one of items 27 to 37, wherein the additive is a filler.

[0230] 39. The fiber according to item 38, wherein the filler is lignin or contains lignin.

[0231] 40. The fiber according to any one of items 27 to 39, wherein, based on 100% by weight of the total fiber weight, the fiber contains a total of 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight of additives.

[0232] 41. The fiber according to any one of the preceding items, wherein the fiber fineness is 0.5 to 8 denier, preferably 0.8 to 6 denier, more preferably 0.9 to 3 denier, even more preferably 1.0 to 2 denier, even more preferably 1.0 to 1.5 denier, even more preferably 1.1 to 1.2 denier.

[0233] 42. The fiber according to any one of the preceding items, wherein the fiber is a short fiber.

[0234] 43. The fiber according to item 42, wherein the fiber has a short fiber length of 2 to 80 mm, preferably 5 to 70 mm, more preferably 10 to 60 mm, even more preferably 15 to 50 mm, even more preferably 20 to 40 mm, even more preferably 22 to 35 mm, even more preferably 25 to 32 mm.

[0235] 44. The fiber according to any one of items 1 to 43, wherein the fiber is a filament.

[0236] 45. The fiber according to any one of the preceding items, wherein the fiber according to EN 13432 is biodegradable.

[0237] 46. ​​A fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate,

[0238] The fiber comprises two parts in the longitudinal direction, one part being a thicker part and the other part being a thinner part. The thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction.

[0239] The thicker portion has at least a cavity, and the thinner portion has at least a dense structure.

[0240] 47. The fiber according to item 46, wherein the thicker portion and the thinner portion are arranged in an alternating pattern along the longitudinal direction of the fiber.

[0241] 48. The fiber according to item 46 or 47, wherein the lengths of the thicker portion and the thinner portion along the longitudinal direction of the fiber are irregular.

[0242] 49. The fiber according to any one of items 46 to 48, wherein the cavity extends in the longitudinal direction of the fiber more than it extends in the direction perpendicular to the longitudinal direction of the fiber.

[0243] 50. The fiber according to any one of items 46 to 49, wherein the cavity has an irregular circumference.

[0244] 51. The fiber according to item 50, wherein the circumference is irregular in a plane conceived in a direction perpendicular to the longitudinal direction of the fiber.

[0245] 52. The fiber according to any one of items 46 to 51, wherein the fiber is a crimped fiber.

[0246] 53. The fiber according to any one of items 46 to 52, wherein the fiber is the fiber according to any one of items 1 to 45.

[0247] 54. A hollow fiber made from a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate.

[0248] 55. The hollow fiber according to item 55, wherein the hollow fiber is further defined as in any one of items 4 to 39.

[0249] 56. A yarn comprising fibers according to any one of items 1 to 55.

[0250] 57. A textile comprising the fiber according to any one of items 1 to 55 or the yarn according to item 56.

[0251] 58. The textiles according to item 57, wherein the textiles are clothing or home textiles.

[0252] 59. The textiles according to item 58, wherein the garment is selected from shirts, polo shirts, trousers, jackets, underwear, socks, coats, shoes and shoelaces.

[0253] 60. The textiles according to item 58, wherein the home textiles are selected from curtains, carpets, blankets, sheets, duvets, duvet covers, mattress covers and towels.

[0254] 61. A method for preparing fibers according to any one of items 1 to 54, comprising:

[0255] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0256] - The precursor fibers are cooled under a temperature gradient to obtain fibers.

[0257] 62. The method according to item 61, wherein a temperature gradient is generated by cooling the precursor fibers from one side.

[0258] 63. The method according to item 61 or 62, wherein the cooling is achieved by air cooling.

[0259] 64. The method according to any one of items 61 to 64, wherein the melt comprises 30% to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0260] 65. The method according to any one of items 61 to 64, wherein the melt comprises 10% to 60% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0261] 66. The method according to any one of items 61 to 65, wherein the melt comprises 1 to 25% by weight of polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0262] 67. The method according to any one of items 61 to 66, wherein the melt comprises 42% to 62% by weight of aliphatic polyester, 26% to 46% by weight of aromatic-aliphatic polyester and 2% to 22% by weight of polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aromatic-aliphatic polyester and polyhydroxyalkanoate.

[0263] 68. The method according to any one of items 61 to 67, wherein the melt further comprises at least one additive.

[0264] 69. The method according to item 68, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, fillers, and any combination thereof.

[0265] 70. The method according to item 69, wherein the additive is a flame retardant.

[0266] 71. The method according to item 70, wherein the melt contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of flame retardant, based on 100% by weight of the total melt weight.

[0267] 72. The method according to any one of items 68 to 71, wherein the total amount of the additive is 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight, based on 100% by weight of the total melt weight.

[0268] 73. The method according to any one of items 61 to 72, wherein the fiber is prepared as a short fiber.

[0269] 74. The method according to any one of items 61 to 72, wherein the fiber is prepared into a filament.

[0270] 75. Use of a melt comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are defined as in any one of items 1 to 53.

[0271] 76. Use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

[0272] 77. A mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate.

[0273] 78. The mixture according to item 77, wherein the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate are further defined as in any one of items 11 to 25.

[0274] 79. The mixture according to item 77 or 78, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0275] 80. The mixture according to any one of items 77 to 79, wherein the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate are present in particulate form.

[0276] 81. The mixture according to item 80, wherein the particles are selected from fine particles, pellets, extrudates, beads, granules, and any combination thereof.

[0277] 82. The mixture according to item 80 or item 81, wherein the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate are in particulate form.

[0278] 83. The mixture according to any one of items 77 to 82, wherein the mixture comprises 30% to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0279] 84. The mixture according to items 77 to 83, wherein the mixture comprises 10% to 60% by weight of aliphatic-aromatic polyester based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0280] 85. The mixture according to any one of items 77 to 84, wherein the mixture comprises 1% to 25% by weight of polyhydroxyalkanoate based on the total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0281] 86. A mixture according to any one of items 77 to 85, wherein, based on a total amount of 100% by weight of aliphatic polyester, aromatic-aliphatic polyester and polyhydroxyalkanoate, the mixture comprises 42% to 62% by weight of aliphatic polyester, 26% to 46% by weight of aromatic-aliphatic polyester and 2% to 22% by weight of polyhydroxyalkanoate.

[0282] 87. The mixture according to any one of items 77 to 86, wherein the mixture further comprises at least one additive.

[0283] 88. The mixture according to item 87, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, fillers, and any combination thereof.

[0284] 89. The mixture according to item 88, wherein the additive is a flame retardant.

[0285] 90. The mixture according to item 89, wherein, based on 100% by weight of the total weight of the mixture, the mixture contains 0.01-5% by weight, preferably 0.1-4% by weight, more preferably 0.2-3% by weight, and even more preferably 0.3-2% by weight of a flame retardant.

[0286] 91. The mixture according to any one of items 87 to 90, wherein the total amount of the additive is 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight, based on 100% by weight of the total weight of the mixture.

[0287] 92. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers, wherein the fibers are as defined in any one of items 1 to 76.

[0288] 93. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of hollow fibers.

Claims

1. A method for preparing fibers, comprising: - A melt containing aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; as well as - The precursor fibers are cooled under a temperature gradient to obtain the fibers.

2. The method of claim 1, wherein the temperature gradient is generated by one or more temperature control elements.

3. The method of claim 2, wherein the one or more temperature control elements are arranged such that the precursor fibers are cooled from one side.

4. The method according to any one of the preceding claims, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

5. The method according to any one of the preceding claims, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene succinate, polybutylene oxalate, polybutylene malonate, polybutylene malonate, polybutylene-co-adipate (PBSA), polybutylene-co-azelate (PBSAz), polybutylene-co-brasinate (PBSBr), and any combination thereof.

6. The method according to any one of the preceding claims, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polybutylene co-succinate (PBSA), polybutylene co-azelate (PBSAz), polybutylene co-brasuccinate (PBSBr), and any combination thereof.

7. The method according to any one of the preceding claims, wherein the aliphatic polyester is polybutylene succinate (PBS).

8. The method according to any one of the preceding claims, wherein the fiber comprises 30% to 70% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

9. The method according to any one of the preceding claims, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol.

10. The method according to any one of the preceding claims, wherein the aliphatic-aromatic polyester is selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacate terephthalate (PBSeT), and any combination thereof.

11. The method according to any one of the preceding claims, wherein the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT).

12. The method according to any one of the preceding claims, wherein the fiber comprises 10% to 60% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

13. The method according to any one of the preceding claims, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkylcarboxylic acids.

14. The method according to any one of the preceding claims, wherein the polyhydroxyalkanoate is selected from polyhydroxybutyrate-co-hydroxyhexanoate, polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, and any combination thereof.

15. The method according to any one of the preceding claims, wherein the polyhydroxyalkanoate is selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof.

16. The method according to any one of the preceding claims, wherein, The polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate.

17. The method according to any one of the preceding claims, wherein the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

18. The method according to any one of the preceding claims, wherein the fiber comprises 1% to 25% by weight of the polyhydroxyalkanoate based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

19. The method according to any one of the preceding claims, wherein the fiber comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aliphatic-aromatic polyester and 2% to 22% by weight of the polyhydroxyalkanoate, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

20. The method according to any one of the preceding claims, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

21. The method according to any one of the preceding claims, wherein the fiber further comprises at least one additive.

22. The method of claim 21, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, fillers, and any combination thereof.

23. The method according to claim 22, wherein the flame retardant is a phosphate selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and any combination thereof.

24. A fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. in, The fiber comprises two parts in the longitudinal direction, one part being a thicker part and the other part being a thinner part, wherein the thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction. The thicker portion has at least a cavity, and the thinner portion has at least a dense structure.

25. The fiber according to claim 24, wherein, The thicker and thinner portions are arranged in an alternating pattern along the longitudinal direction of the fiber.

26. The fiber according to claim 24 or 25, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

27. The fiber according to any one of claims 24 to 26, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene succinate, polybutylene oxalate, polybutylene malonate, polybutylene succinate-co-adipate (PBSA), polybutylene succinate-co-azelate (PBSAz), polybutylene succinate-co-brasinate (PBSBr), and any combination thereof.

28. The fiber according to any one of claims 24 to 27, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polybutylene succinate-co-adipate (PBSA), polybutylene succinate-co-azelate (PBSAz), polybutylene succinate-co-brasinate (PBSBr), and any combination thereof.

29. The fiber according to any one of claims 24 to 28, wherein the aliphatic polyester is polybutylene succinate (PBS).

30. The fiber according to any one of claims 24-29, wherein the fiber comprises 30% to 70% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

31. The fiber according to any one of claims 24 to 30, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol.

32. The fiber according to any one of claims 24 to 31, wherein the aliphatic-aromatic polyester is selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacate terephthalate (PBSeT), and any combination thereof.

33. The fiber according to any one of claims 24 to 32, wherein, The aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT).

34. The fiber according to any one of claims 24 to 33, wherein the fiber comprises 10% to 60% by weight of the aliphatic-aromatic polyester based on the total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

35. The fiber according to any one of claims 24 to 34, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkylcarboxylic acids.

36. The fiber according to any one of claims 24 to 35, wherein, The polyhydroxyalkanoate is selected from polyhydroxybutyrate-co-hydroxyhexanoate, polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, and any combination thereof.

37. The fiber according to any one of claims 24 to 36, wherein the polyhydroxyalkanoate is selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof.

38. The fiber according to any one of claims 24 to 37, wherein, The polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate.

39. The fiber according to any one of claims 24 to 38, wherein the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

40. The fiber according to any one of claims 24 to 39, wherein the fiber comprises 1% to 25% by weight of the polyhydroxyalkanoate based on the total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

41. The fiber according to any one of claims 24 to 40, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, the fiber comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aliphatic-aromatic polyester and 2% to 22% by weight of the polyhydroxyalkanoate.

42. The fiber according to any one of claims 24 to 41, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

43. The fiber according to any one of claims 24 to 42, wherein the fiber further comprises at least one additive.

44. The fiber of claim 43, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, fillers, and any combination thereof.

45. The fiber according to claim 44, wherein the flame retardant is a phosphate selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and any combination thereof.

46. ​​The fiber according to any one of claims 24 to 45, wherein the fiber is biodegradable.

47. A hollow fiber made from a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate.

48. The hollow fiber of claim 47, wherein the fiber is biodegradable.

49. A mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, the mixture comprises 30% to 70% by weight of the aliphatic polyester, 10% to 60% by weight of the aliphatic-aromatic polyester, and 1% to 25% by weight of the polyhydroxyalkanoate.

50. The mixture of claim 49, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, the mixture comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aliphatic-aromatic polyester, and 2% to 22% by weight of the polyhydroxyalkanoate.

51. The mixture according to claim 49 or 50, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

52. The mixture according to any one of claims 49 to 51, wherein the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate are in particulate form.

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