Algae cellulose fiber

Abstract

The present disclosure relates to a fiber comprising regenerated cellulose wherein the cellulose is obtained from algae and a method of preparing the same.

Description

[0001] This application claims priority to Australian provisional patent application No. 2022903825 filed on December 14, 2022, the entire disclosure of which is incorporated herein by cross-reference. Technical Field

[0002] The present disclosure relates broadly to fibers and textiles made from algal cellulose. Background Art

[0003] Any discussion of the prior art throughout this specification should not be taken as an admission that this prior art is common general knowledge or forms part of the common general knowledge in the field.

[0004] Natural cotton consists of short fibers of highly crystalline cellulose that can be mechanically processed into fabric or yarn.

[0005] Cotton is widely used in the global apparel industry, with cotton products accounting for approximately 20% of the market share. Cotton is a popular material due to its relatively low cost, comfort, and durability.

[0006] However, the use of cotton presents serious environmental concerns. Cotton is a highly water-intensive crop, with an estimated 2,700 liters of water required to produce a single cotton shirt. It is also the world's largest single crop for pesticide consumption.

[0007] It would be desirable to provide fibers, yarns, and / or fabrics having properties comparable to cotton, but utilizing a source of cellulose that can be obtained in an environmentally sustainable manner.

[0008] As a cellulose source, algae offers many advantages over cotton, including higher yields per unit area grown, the ability to grow on non-arable land or in arid regions, and the ability to grow in non-freshwater environments. Therefore, algae is a sustainable alternative to cotton cultivation. Summary of the Invention

[0009] In a first aspect of the present disclosure, there is provided a fiber comprising regenerated cellulose, wherein the cellulose is obtained from algae.

[0010] The following options may be used in conjunction with the first aspect of the present disclosure, alone or in any combination.

[0011] The cellulose obtained from algae may comprise at least about 50% w / w of the fiber.The fiber may consist of regenerated cellulose, and wherein the cellulose is obtained solely from algae.

[0012] The fibers may be filament fibers. Alternatively, the fibers may be staple fibers.

[0013] The algae may be algae of the genus Chaetomorpha.

[0014] The fibers may have a diameter between about 100 μm and 500 μm. The fibers may have a diameter between about 200 μm and about 300 μm.

[0015] In a second aspect of the present disclosure, a yarn is provided, comprising the fiber according to the first aspect of the present disclosure.

[0016] The following options may be used in conjunction with the second aspect of the present disclosure, alone or in any combination.

[0017] The yarn may have a yarn count between about 5 tex and about 50 tex.

[0018] In a third aspect of the present disclosure, there is provided a method of preparing a fiber comprising regenerated cellulose obtained from algae, the method comprising:

[0019] (i) extracting cellulose from algae;

[0020] (ii) dissolving cellulose in a solvent to form a dope solution; and

[0021] (iii) Extruding the spinning dope into an anti-solvent to prepare fibers.

[0022] The following options may be used in conjunction with the third aspect of the present disclosure, alone or in any combination.

[0023] The algae may be of the genus Cladosporium.

[0024] Step (i) may comprise treating the algae with an alkaline aqueous solution.

[0025] After step (i), step (ia) of hydrolyzing the cellulose with an acidic aqueous solution at an elevated temperature to provide hydrolyzed cellulose may be performed. Step (ia) may further comprise: neutralizing the hydrolyzed cellulose.

[0026] After step (i), a step (ib) of removing water from the cellulose may be performed.

[0027] The solvent may be selected from the group consisting of an ionic liquid, carbon disulfide, N-methylmorpholine N-oxide, and a cuprammonium solution. The solvent may be an ionic liquid. The ionic liquid may be composed of an imidazolium, pyridinium, guanidinium, or ammonium cation and a halogen anion or an acetate anion. The ionic liquid may be selected from the group consisting of 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium chloride, 1-N-allyl-3-methylimidazolium chloride, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enyl acetate ([mTBDH][OAc]), N,N,N,N-tetramethylguanidine acetate, and 1,5-diazabicyclo[4.3.0]non-5-ene ([DBNH][OAc]). The solvent may be 1-ethyl-3-methylimidazolium acetate.

[0028] The cellulose concentration of the spinning dope may be between about 2% w / w and about 15% w / w. The cellulose concentration of the spinning dope may be between about 5% w / w and about 12% w / w.

[0029] Step (ii) may further comprise heating the cellulose in the solvent.

[0030] Step (iii) may comprise dry jet wet spinning. Alternatively, step (iii) may comprise wet spinning.

[0031] The anti-solvent may be selected from the group consisting of water, methanol, ethanol, and mixtures of two or more thereof. The anti-solvent may be ethanol.

[0032] The method may further comprise the step (iv) of drying the fibers.

[0033] In a fourth aspect of the present disclosure, provided is a fiber prepared by the method described in the third aspect of the present disclosure.

[0034] The following options may be used alone or in any combination in conjunction with the first or fourth aspect of the present disclosure.

[0035] The fibers may have a load-bearing capacity of at least about 30 g.

[0036] The fibers may have a breaking load of at least about 30 g.

[0037] The fiber can have a breaking force of at least about 0.2 N at a testing speed of 50 mm / min.

[0038] The fiber can have a fracture toughness of at least about 0.2 cN / tex at a testing speed of 50 mm / min.

[0039] The fibers may have an elongation of at least about 8% at a testing speed of 50 mm / min.

[0040] In a fifth aspect of the present disclosure, a fabric is provided, which is woven or knitted from the fiber according to the first aspect or the fourth aspect of the present disclosure or the yarn according to the second aspect of the present disclosure.

[0041] The following options may be used in conjunction with the fifth aspect of the present disclosure, alone or in any combination.

[0042] The fibers of the first or fourth aspect of the present disclosure or the yarns of the second aspect of the present disclosure may account for at least 50% w / w of the fabric. The fabric may be woven or knitted solely from the fibers of the first or fourth aspect of the present disclosure or the yarns of the second aspect of the present disclosure.

[0043] The fabric may comprise at least 50% w / w cellulose obtained from algae.

[0044]

definition

[0045] The following are some definitions that may be helpful in understanding the description of the present disclosure. These are intended as general definitions and should in no way limit the scope of the present disclosure to only these terms, but are provided for a better understanding of the following description.

[0046] Throughout this specification, unless the context requires otherwise, the word "comprise" or variations such as "have" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.

[0047] The terms "a" and "an" are used herein to refer to one or more (ie, to at least one) of the grammatical object of the article. For example, "an element" means one element or more than one element.

[0048] In the context of this specification, the term "about" is understood to mean ±10% of the quoted value.

[0049] Any numerical range described herein is intended to include all subranges of the same numerical precision contained within the range. For example, a range of 1.0 to 5.0 is intended to include all subranges between (and including) the minimum value of 1.0 and the maximum value of 5.0, i.e., having a minimum value equal to or greater than 1.0 and a maximum value equal to or less than 5.0, such as 2.1 to 4.5. Any maximum numerical limit described herein is intended to include all lower numerical limits contained therein, and any minimum numerical limit described herein is intended to include all higher numerical limits contained therein.

[0050] Any description herein of prior art documents, or statements herein derived from or based upon such documents, does not constitute an admission that these documents or derived statements are part of the common general knowledge in the relevant field.

[0051] For descriptive purposes, all documents cited herein are incorporated by reference in their entirety unless otherwise indicated. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 , spinning of cellulose spinning dope obtained from Chaetocystis algae using a syringe and a syringe pump.

[0053] Figure 2 , filament fibers prepared by spinning a spinning solution of cellulose obtained from Chaetocystis algae using a syringe and a syringe pump.

[0054] Figure 3 , Electron micrograph of filament fibers obtained by spinning a spinning dope of cellulose obtained from Chaetoceros algae using a syringe with a 21G needle and a syringe pump.

[0055] Figure 4 , Electron micrograph of filament fibers obtained by spinning a spinning dope of cellulose obtained from Chaetoceros algae using a syringe with a 22G needle and a syringe pump.

[0056] Figure 5 , Thermogravimetric analysis of Oedogonium fiber (A), acid-washed Oedogonium fiber (B), Oedogonium fiber (C), Oedogonium fiber from lactate (D) and acid-washed Oedogonium fiber (E).

[0057] FIG6 . Load-bearing capacity determination of filaments obtained by (a) spinning a cellulose dope obtained from Chaete algae using a syringe with a 21G needle and (b) spinning a filament obtained from a microcrystalline cellulose dope using a syringe with a 21G needle.

[0058] Figure 7 , The tensile strength of filament fibers obtained by spinning a spinning solution of cellulose obtained from Chaetocystis algae using a syringe with a 27G needle was measured.

[0059] Figure 8 , woven fabrics made from cellulose fibers of Chaetocystis sclerotium. DETAILED DESCRIPTION

[0060] The present inventors have discovered that regenerated cellulose fibers made from cellulose obtained from algae can be used to make yarns and fabrics having useful properties similar to cotton. In particular, regenerated cellulose fibers made from cellulose obtained from algae of the genus Cladophora provide yarns and fabrics having unexpectedly excellent properties.

[0061] Algae-derived cellulose fiber and yarn

[0062] In a first aspect of the present disclosure, a fiber comprising regenerated cellulose is provided, wherein the cellulose is obtained from algae. Regenerated cellulose refers to cellulose that has been dissolved in a solvent and then "regenerated" (i.e., precipitated) into a desired form (e.g., fiber). Naturally occurring cellulose is typically cellulose I, which comprises parallel chains of glucose units without inter-sheet hydrogen bonds. Regenerated cellulose is typically cellulose II, which is a more thermodynamically stable form and comprises antiparallel chains of glucose units with inter-sheet hydrogen bonds.

[0063] The fiber described in the first aspect of the present disclosure comprises regenerated cellulose obtained from algae. That is, cellulose is extracted from algae, for example, using the process described in connection with the third aspect of the present disclosure. Algae are generally defined as aquatic photosynthetic eukaryotes that lack many cell and tissue types found in terrestrial plants, such as stomata, xylem, and phloem. Algae include seaweed and microalgae. Examples of algae include species of Cladaphora, Cladaphora, Cladaphora, Chlorella, and Scenedesmus. In some embodiments, the algae may be of the genus Cladaphora. In some embodiments, the algae may be of the genus Cladaphora or Cladaphora. In some embodiments, the algae may be of the genus Cladaphora.

[0064] The fibers comprising regenerated cellulose of the first aspect of the present disclosure may comprise at least about 50% w / w cellulose obtained from algae, or at least about 55% w / w, 60% w / w, 65% w / w, 70% w / w, 75% w / w, 80% w / w, 85% w / w, 90% w / w, 95% w / w, 96% w / w, 97% w / w, 98% w / w, or at least about 99% w / w cellulose obtained from algae. The fiber comprising regenerated cellulose of the first aspect of the present disclosure may comprise about 50% w / w cellulose obtained from algae, or about 55% w / w, 60% w / w, 65% w / w, 70% w / w, 75% w / w, 80% w / w, 85% w / w, 90% w / w, 95% w / w, 96% w / w, 97% w / w, 98% w / w, or about 99% w / w cellulose obtained from algae. The fiber may be composed of regenerated cellulose, wherein 100% w / w of the cellulose is obtained from algae. That is, the cellulose may be obtained solely from algae. In other words, the fiber may be composed of cellulose obtained from algae.

[0065] The fibers comprising regenerated cellulose of the first aspect of the present disclosure may also comprise cellulose from non-algae sources, as well as cellulose obtained from algae. For example, the fibers may comprise cellulose obtained from wood pulp or cellulose obtained from bamboo. The fibers may comprise microcrystalline cellulose. The fibers comprising regenerated cellulose of the first aspect of the present disclosure may comprise up to about 50% w / w cellulose obtained from non-algae sources, or up to about 5% w / w, 10% w / w, 15% w / w, 20% w / w, 25% w / w, 30% w / w, 35% w / w, 40% w / w, or up to about 45% w / w cellulose obtained from non-algae sources. The fibers comprising regenerated cellulose of the first aspect of the present disclosure may comprise about 50% w / w cellulose obtained from a non-algal source, or about 5% w / w, 10% w / w, 15% w / w, 20% w / w, 25% w / w, 30% w / w, 35% w / w, 40% w / w, or about 45% w / w cellulose obtained from a non-algal source.

[0066] The fiber comprising regenerated cellulose described in the first aspect of the present disclosure can be a staple fiber. Staple fibers are fibers with discrete lengths. Alternatively, the fiber comprising regenerated cellulose described in the first aspect of the present disclosure can be a filament fiber. Filament fibers are continuous fibers with indefinite lengths.

[0067] The fiber comprising regenerated cellulose of the first aspect of the present disclosure may have a diameter of between about 100 μm and about 400 μm, or between about 100 μm and 200 μm, 100 μm and 300 μm, 200 μm and 300 μm, 200 μm and 400 μm, or between about 300 μm and 400 μm. The fiber comprising regenerated cellulose of the first aspect of the present disclosure may have a diameter of about 100 μm, or about 150 μm, 200 μm, 250 μm, 300 μm, 350 μm, or about 400 μm.

[0068] In the second aspect of the present disclosure, a yarn is provided, comprising the fiber described in the first aspect of the present disclosure. That is, the fiber comprising regenerated cellulose described in the first aspect of the present disclosure can be spun into yarn. The yarn can be spun using conventional methods known to those skilled in the art. When the fiber is a staple fiber, the yarn can be a staple yarn. When the fiber is a filament fiber, the yarn can be a filament yarn. The yarn can be spun from a mixture of staple fibers and filament fibers. The yarn can contain at least 50% w / w of the fiber described in the first aspect of the present disclosure, or at least about 55% w / w, 60% w / w, 65% w / w, 70% w / w, 75% w / w, 80% w / w, 85% w / w, 90% w / w, 95% w / w, 96% w / w, 97% w / w, 98% w / w or at least about 99% w / w of the fiber described in the first aspect of the present disclosure. The yarn may comprise 50% w / w of the fiber of the first aspect of the present disclosure, or about 55% w / w, 60% w / w, 65% w / w, 70% w / w, 75% w / w, 80% w / w, 85% w / w, 90% w / w, 95% w / w, 96% w / w, 97% w / w, 98% w / w, or about 99% w / w of the fiber of the first aspect of the present disclosure. The yarn may be composed of the fiber of the first aspect of the present disclosure, that is, the yarn may comprise 100% w / w of the fiber of the first aspect of the present disclosure.

[0069] The yarn described in second aspect of the present disclosure can have the yarn count between about 5tex and about 50tex, or the yarn count between about 5tex to 10tex, 5tex to 20tex, 5tex to 40tex, 5tex to 40tex, 10tex to 20tex, 10tex to 30tex, 10tex to 40tex, 10tex to 50tex, 20tex to 30tex, 20tex to 40tex, 20tex to 50tex, 30tex to 40tex, 30tex to 50tex, or about 40tex to about 50tex. Yarn can have the yarn count between about 10tex and about 20tex. Yarn can have the yarn count between about 5tex and about 20tex. Yarn can have the yarn count between about 5tex and about 5tex, or the yarn count of about 5tex, 10tex, 20tex, 30tex, 40tex or about 50tex.

[0070] A method for preparing algae-derived cellulose fibers

[0071] In a third aspect of the present disclosure, there is provided a method of preparing a fiber comprising regenerated cellulose obtained from algae, the method comprising:

[0072] (i) extracting cellulose from algae;

[0073] (ii) dissolving cellulose in a solvent to form a spinning dope; and

[0074] (iii) Extruding the spinning dope into an anti-solvent to prepare fibers.

[0075] The fiber comprising regenerated cellulose obtained from algae prepared by the method according to the third aspect of the present disclosure may be the fiber according to the first aspect of the present disclosure.

[0076] Step (i) of the method of the third aspect of the present disclosure comprises: extracting cellulose from algae. The algae can be as described above with respect to the first aspect of the present disclosure. In some embodiments, the algae can be algae of the genus Chaetocystis. In some embodiments, the algae can be algae of the genus Chaetocystis or the genus Schetocystis. In some embodiments, the algae can be algae of the genus Schetocystis. Prior to step (i), the algae can optionally be bleached. Step (i) may comprise: treating the algae with an alkaline aqueous solution. After treatment with the alkaline aqueous solution, the solids can be separated, for example, by centrifugation to provide cellulose. The alkaline aqueous solution can be any suitable strong base, such as an aqueous sodium hydroxide solution. The alkaline aqueous solution can have a concentration of about 1M to 10M, or about 2M to 7M, or about 5M. The alkaline aqueous solution can be a 5M aqueous sodium hydroxide solution.

[0077] In some embodiments, step (i) may be followed by a step (ia) of hydrolyzing the cellulose with an acidic aqueous solution at an elevated temperature to provide hydrolyzed cellulose. Acidic hydrolysis can increase the crystallinity of the resulting cellulose by removing amorphous cellulose. Acidic hydrolysis also results in fibers having increased tensile strength and thermal stability compared to fibers prepared from cellulose that has not been acid-hydrolyzed. The acidic aqueous solution may be any suitable strong acid, such as an aqueous hydrochloric acid solution. The acidic aqueous solution may have a concentration of about 0.5M to 5M, or about 2M to 3M, or about 2.5M. The acidic aqueous solution may be a 2.5M aqueous hydrochloric acid solution. The hydrolysis may occur at an elevated temperature between about 50°C and about 100°C. The hydrolysis may occur at an elevated temperature of about 100°C. After the acidic hydrolysis, the cellulose may be neutralized. That is, the cellulose may be washed with water and / or treated with alkali so that the pH of the cellulose reaches about 7.

[0078] In some embodiments, step (i) and step (ia) (if present) may be followed by a step (ib) of removing water from the cellulose. This may be accomplished by any conventional technique known to those skilled in the art. For example, the cellulose may be centrifuged and then freeze-dried.

[0079] In step (ii) of the third aspect of the present disclosure, the cellulose extracted from the algae in step (i) is dissolved in a solvent to form a spinning solution. The solubility of cellulose in various solvents is well known. The solvent can be selected from the group consisting of ionic liquids, carbon disulfide, N-methylmorpholine N-oxide and copper ammonia solution. Copper ammonia solution refers to an aqueous solution of the metal ammonia complex [Cu(NH3)4(H2O)2](OH)2, also known as Schweizer reagent.

[0080] In some embodiments, dissolving the cellulose in the solvent may include heating the cellulose in the solvent. The cellulose in the solvent may be heated at a temperature of at least about 50°C or between about 50°C and about 100°C.

[0081] In some embodiments, the solvent can be an ionic liquid. Suitable ionic liquids for dissolving cellulose typically contain imidazolium, pyridinium, guanidinium or ammonium cations and halogen anions or acetate anions. For example, the ionic liquid can be selected from the group consisting of 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium chloride, 1-N-allyl-3-methylimidazolium chloride, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enyl acetate ([mTBDH][OAc]), N,N,N,N-tetramethylguanidine acetate, and 1,5-diazabicyclo[4.3.0]non-5-ene ([DBNH][OAc]). The ionic liquid, i.e., solvent, can be 1-ethyl-3-methylimidazolium acetate.

[0082] A solution of cellulose dissolved in a solvent is called a spinning dope. The concentration of cellulose in the spinning dope can be between about 2% w / w and about 15% w / w, or can be 2% w / w to 3% w / w, 2% w / w to 4% w / w, 2% w / w to 5% w / w, 2% w / w to 6% w / w, 2% w / w to 7% w / w, 2% w / w to 8% w / w, 2% w / w to 9% w / w, 2% w / w to 10% w / w, 2% w / w to 11% w / w, 2% w / w to 12% w / w, 2% w / w to 13% w / w, 2% w / w to 14% w / w, 3% w / w to 4% w / w, 3% w / w to 5% w / w, 3% w / w to 6% w / w, 3% w / w to 7% w / w, 3% w / w to 8% w / w, 3% w / w to 9% w / w, 3% w / w to 10% w / w, 3% w / w to 11% w / w, 3% w / w to 12% w / w, 3% w / w to 13% w / w, 3% w / w to 14% w / w, 3% w / w to 15% w / w, 4% w / w to 5% w / w, 4% w / w to 6% w / w, 4% w / w to 7% w / w, 4% w / w to 8% w / w, 4% w / w to 9% w / w, 4% w / w to 10% w / w, 4% w / w to 11% w / w, 4% w / w to 12% w / w, 4% w / w to 13% w / w, 4% w / w to 14% w / w, 4% w / w to 15% w / w, 5% w / w to 6% w / w, 5% w / w to 7% w / w, 5% w / w to 8% w / w, 5% w / w to 9% w / w, 5% w / w to 10% w / w, 5% w / w to 11% w / w, 5% w / w to 12% w / w, 5% w / w to 13% w / w, 5% w / w to 14% w / w, 5% w / w to 15% w / w, 6% w / w to 7% w / w, 6% w / w to 8% w / w, 6% w / w to 9% w / w, 6% w / w to 10% w / w, 6% w / w to 11% w / w, 6% w / w to 12% w / w, 6% w / w to 13% w / w, 6% w / w to 14% w / w, 6% w / w to 15% w / w, 7% w / w to 8% w / w, 7% w / w to 9% w / w, 7% w / w to 10% w / w, 7% w / w to 11% w / w, 7% w / w to 12% w / w, 7% w / w to 13% w / w, 7% w / w to 14% w / w, 7% w / w to 15% w / w, 8% w / w to 9% w / w, 8% w / w to 10% w / w, 8% w / w to 11% w / w, 8% w / w to 12% w / w, 8% w / w to 13% w / w, 8% w / w to 14% w / w, 8% w / w to 15% w / w, 9% w / w to 10% w / w, 9% w / w to 11% w / w, 9% w / w to 12% w / w, 9% w / w to 13% w / w, 9% w / w to 14% w / w,9% w / w to 15% w / w, 10% w / w to 11% w / w, 10% w / w to 12% w / w, 10% w / w to 13% w / w, 10% w / w to 14% w / w, 10% w / w to 15% w / w, 11% w / w to 12% w / w, 11% w / w to 13% w / w, 11% w / w to 14% w / w, 11% w / w to 15% w / w, 12% w / w to 13% w / w, 12% w / w to 14% w / w, 12% w / w to 15% w / w, 13% w / w to 14% w / w, 13% w / w to 15% w / w, or between about 14% w / w and about 15% w / w. The concentration of cellulose in the spinning solution may be between about 5% w / w and about 12% w / w. The concentration of cellulose in the spinning solution may be between about 4% w / w and about 7% w / w. The concentration of cellulose in the spinning solution may be between about 5% w / w and about 7% w / w. The concentration of cellulose in the spinning solution may be between about 5% w / w and about 6.5% w / w. The concentration of cellulose in the spinning solution may be about 2% w / w, or about 3% w / w, 4% w / w, 5% w / w, 5.5% w / w, 6% w / w, 6.5% w / w, 7% w / w, 8% w / w, 9% w / w, 10% w / w, 11% w / w, 12% w / w, 13% w / w, 14% w / w, or about 15% w / w.

[0083] In step (iii) of the third aspect of the present disclosure, the spinning solution is extruded to form fibers. The spinning solution can be extruded directly into an antisolvent during wet spinning. Alternatively, the spinning solution can be extruded into an air gap before entering the antisolvent during dry-jet wet spinning. Antisolvents for regenerated cellulose are well known. In some embodiments, the solvent can be a polar protic solvent. In some embodiments, the solvent can be selected from the group consisting of water, methanol, ethanol, and a mixture of two or more thereof. The antisolvent can be ethanol. The extruded cellulose can be retained in the antisolvent for a period of time to allow phase separation to occur. The period of time can be between about 0.5 h and about 5 h, or between about 1 h and 4 h, or between about 2 h and about 3 h. The period of time can be between about 2 h and about 3 h. The period of time can be 1 h, 2 h, 3 h, 4 h, or 5 h. The period of time can be 2 h. The period of time can be 3 h.

[0084] The method of the third aspect of the present disclosure may include a step (iv) of drying the fibers comprising regenerated cellulose obtained from algae. This may be done in any conventional manner. For example, the fibers may be dried in an oven at an elevated temperature such as 100°C.

[0085] In a fourth aspect of the present disclosure, provided is a fiber prepared by the method described in the third aspect of the present disclosure.

[0086] Characteristics of algae-derived cellulose fibers

[0087] The fiber of the first or fourth aspect of the present disclosure may have a load-bearing capacity of at least about 30 g, or at least about 35 g, 40 g, 45 g, 50 g, 55 g, or about 60 g. The fiber of the first or fourth aspect of the present disclosure may have a load-bearing capacity of at least about 50 g. Load-bearing capacity refers to the maximum weight that a fiber can withstand before breaking.

[0088] The fiber of the first or fourth aspect of the present disclosure may have a breaking load of at least about 30 g, or at least about 35 g, 40 g, 45 g, 50 g, 55 g, or about 60 g. The fiber of the first or fourth aspect of the present disclosure may have a breaking load of at least about 50 g.

[0089] The load-bearing capacity and breaking load are tested by suspending gradually increasing weights from a fiber approximately 30 mm long. The breaking load is the load at which the fiber breaks. The maximum load that can be suspended without breaking is the load-bearing capacity.

[0090] The fiber of the first aspect or the fourth aspect of the present disclosure may have a breaking force of at least about 0.2 N, or at least about 0.2 N, 0.3 N, 0.4 N, or 0.5 N at a test speed of 50 mm / min, measured according to ASTM D2256 / D2256M-21. The fiber of the first aspect or the fourth aspect of the present disclosure may have a breaking force of at least about 0.3 N at a test speed of 50 mm / min. The fiber of the first aspect or the fourth aspect of the present disclosure may have a breaking force of about 0.2 N, or about 0.2 N, 0.3 N, 0.4 N, or 0.5 N at a test speed of 50 mm / min. The fiber of the first aspect or the fourth aspect of the present disclosure may have a breaking force of about 0.3 N at a test speed of 50 mm / min.

[0091] The fiber described in the first aspect or the fourth aspect of the present disclosure can have a fracture toughness of at least about 0.2 cN / tex, or at least about 0.2 cN / tex, 0.3 cN / tex, 0.4 cN / tex or 0.5 cN / tex at a test speed of 50 mm / min. The fiber described in the first aspect or the fourth aspect of the present disclosure can have a fracture force of at least about 0.3 cN / tex at a test speed of 50 mm / min. The fiber described in the first aspect or the fourth aspect of the present disclosure can have a fracture force of about 0.2 cN / tex, or about 0.2 cN / tex, 0.3 cN / tex, 0.4 cN / tex or 0.5 cN / tex at a test speed of 50 mm / min. The fiber described in the first aspect or the fourth aspect of the present disclosure can have a fracture force of about 0.3 cN / tex at a test speed of 50 mm / min. Fracture toughness is defined as fracture force (measured according to ASTM D2256 / D2256M-21 standard as defined above) divided by fiber fineness. Fineness is defined as the mass of 9000 meters of fiber.

[0092] The fibers described in the first or fourth aspect of the present disclosure may have an elongation of at least about 8%, or at least about 9%, 10%, 11%, 12%, 13%, 14%, or at least about 15% at a test speed of 50 mm / min. The fibers described in the first or fourth aspect of the present disclosure may have an elongation of at least about 10% at a test speed of 50 mm / min. The fibers described in the first or fourth aspect of the present disclosure may have an elongation of about 8%, or about 9%, 10%, 11%, 12%, 13%, 14%, or about 15% at a test speed of 50 mm / min. The fibers described in the first or fourth aspect of the present disclosure may have an elongation of about 10% at a test speed of 50 mm / min. In order to determine the elongation, it is necessary to record the gauge length before the breaking force test according to the ASTM D2256 / D2256M-21 standard, and the gauge length at the end of the breaking force test. Elongation is the gauge length at the end of the test divided by the gauge length before the test, expressed as a percentage.

[0093] A fabric made from algae-derived cellulose

[0094] In a fifth aspect of the present disclosure, a fabric woven or knitted from the fibers of the first or fourth aspects of the present disclosure or the yarn of the second aspect of the present disclosure is provided. The fabric may be a woven fabric. The fibers of the first or fourth aspects of the present disclosure or the yarn of the second aspect of the present disclosure may comprise at least 50% w / w of the fabric, or at least 60%, 70%, 80%, 90%, or 95% w / w of the fabric. The fibers of the first or fourth aspects of the present disclosure or the yarn of the second aspect of the present disclosure may comprise 100% w / w of the fabric, that is, the fabric may be woven or knitted solely from the fibers of the first or fourth aspects of the present disclosure or the yarn of the second aspect of the present disclosure. The fabric may contain at least 50% w / w cellulose obtained from algae. The fabric may contain at least 60%, 70%, 80%, 90%, or 95% w / w cellulose obtained from algae. The fabric may comprise 100% w / w cellulose obtained from algae, that is, the fabric may consist of cellulose obtained from algae.

[0095] The present disclosure may be described with reference to the following numbered embodiments.

[0096] 1. A fiber comprising regenerated cellulose, wherein the cellulose is obtained from algae.

[0097] 2. The fiber of Form 1, wherein the cellulose obtained from algae comprises at least about 50% w / w of the fiber.

[0098] 3. Fiber according to form 1 or form 2, wherein the fiber consists of regenerated cellulose and wherein the cellulose is obtained exclusively from algae.

[0099] 4. The fiber according to any one of forms 1 to 3, wherein the fiber is a filament fiber.

[0100] 5. The fiber according to any one of forms 1 to 3, wherein the fiber is a staple fiber.

[0101] 6. The fiber according to any one of forms 1 to 5, wherein the algae is of the genus Stenophyte.

[0102] 7. The fiber of any one of forms 1 to 6, wherein the fiber has a diameter between about 100 μm and 500 μm.

[0103] 8. The fiber of any one of forms 1 to 7, wherein the fiber has a diameter of between about 200 and about 300 μm.

[0104] 9. A yarn comprising the fiber according to any one of forms 1 to 8.

[0105] 10. The yarn of form 9, wherein the yarn has a yarn count between about 5 tex and about 50 tex.

[0106] 11. A method for preparing fibers comprising regenerated cellulose obtained from algae, the method comprising:

[0107] (i) extracting cellulose from the algae;

[0108] (ii) dissolving the cellulose in a solvent to form a spinning dope; and

[0109] (iii) extruding the spinning dope into an anti-solvent to prepare the fiber.

[0110] 12. The method of form 11, wherein the algae is of the genus Cladosporium.

[0111] 13. The method according to Form 11 or Form 12, wherein step (i) comprises treating the algae with an alkaline aqueous solution.

[0112] 14. A method according to any one of forms 11 to 13, wherein step (i) is followed by a step (ia) of hydrolyzing the cellulose with an acidic aqueous solution at elevated temperature to provide hydrolyzed cellulose.

[0113] 15. The method of form 14, wherein step (ia) further comprises: neutralizing the hydrolyzed cellulose.

[0114] 16. A process according to any one of forms 11 to 15, wherein step (i) is followed by a step (ib) of removing water from the cellulose.

[0115] 17. The method of any one of Forms 11 to 16, wherein the solvent is selected from the group consisting of ionic liquids, carbon disulfide, N-methylmorpholine N-oxide, and cuprammonium solution.

[0116] 18. A method according to any one of Forms 11 to 17, wherein the solvent is an ionic liquid.

[0117] 19. The method according to Form 17 or Form 18, wherein the ionic liquid is composed of an imidazolium, pyridinium, guanidinium or ammonium cation and a halide anion or an acetate anion.

[0118] 20. A method according to any one of Forms 17 to 19, wherein the ionic liquid is selected from the group consisting of 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium chloride, 1-N-allyl-3-methylimidazolium chloride, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enyl acetate ([mTBDH][OAc]), N,N,N,N-tetramethylguanidine acetate and 1,5-diazabicyclo[4.3.0]non-5-ene ([DBNH][OAc]).

[0119] 21. The method of any one of Forms 11 to 20, wherein the solvent is 1-ethyl-3-methylimidazolium acetate.

[0120] 22. The method of any one of forms 11 to 21, wherein the cellulose concentration of the spinning solution is between about 2% w / w and about 15% w / w.

[0121] 23. The method of any one of forms 11 to 22, wherein the cellulose concentration of the spinning solution is between about 5% w / w and about 12% w / w.

[0122] 24. The method of any one of forms 11 to 23, wherein step (ii) further comprises heating the cellulose in the solvent.

[0123] 25. A method according to any one of forms 11 to 24, wherein step (iii) comprises dry jet wet spinning.

[0124] 26. A method according to any one of forms 11 to 24, wherein step (iii) comprises wet spinning.

[0125] 27. The method of any one of Forms 11 to 26, wherein the antisolvent is selected from the group consisting of water, methanol, ethanol, and mixtures of two or more thereof.

[0126] 28. The method of any one of Forms 11 to 27, wherein the antisolvent is ethanol.

[0127] 29. A method according to any one of forms 11 to 28, further comprising the step (iv) of drying the fibers.

[0128] 30. A fiber prepared by the method of any one of Forms 11 to 29.

[0129] 31. The fiber of any one of Forms 1 to 9 or Form 30, wherein the fiber has a load-bearing capacity of at least about 30 g.

[0130] 32. A fiber according to any one of Forms 1 to 9, 30 or 31, wherein the fiber has a breaking load of at least about 30 g.

[0131] 33. A fiber according to any one of forms 1 to 9 or 30 to 32, wherein the fiber has a breaking force of at least about 0.2 N at a test speed of 50 mm / min.

[0132] 34. A fiber according to any one of forms 1 to 9 or 30 to 33, wherein the fiber has a breaking tenacity of at least about 0.2 cN / tex at a testing speed of 50 mm / min.

[0133] 35. The fiber of any one of Forms 1 to 9 or 30 to 34, wherein the fiber has an elongation of at least about 8% at a testing speed of 50 mm / min.

[0134] 36. A fabric woven or knitted from the fibers of any one of forms 1 to 9 or 30 to 35 or the yarn of form 10.

[0135] 37. A fabric according to form 36, wherein the fibers of any of forms 1 to 9 or 30 to 35 or the yarn of form 10 comprise at least 50% w / w of the fabric.

[0136] 38. A fabric according to form 36 or form 37, wherein the fabric is woven or knitted solely from the fibers of any one of forms 1 to 9 or forms 30 to 35 or the yarn of form 10.

[0137] 39. The fabric of any one of forms 36 to 38, wherein the fabric comprises at least 50% w / w cellulose obtained from algae.

[0138] Example

[0139] The present disclosure is further described below by way of non-limiting examples.

[0140] Method 1 - Extraction of cellulose

[0141] The algae is washed and rinsed, then dried at 60°C overnight and cut into small pieces. The algae pieces are placed in a solution with a pH of 3 to 4 (adjusted with acetic acid) and then treated with 1% w / w sodium hypochlorite. The solution is centrifuged, the supernatant discarded, and the residue filtered and dispersed in water. The dispersion of the bleached algae is heated and stirred at 130°C for 3 to 4 hours, then centrifuged, the supernatant discarded, and the residue filtered and dispersed in water. The dispersion of the bleached algae is then treated with a NaOH solution (5M) to provide cellulose (yield of 20% to 35%). The cellulose is treated with an HCl solution (2.5M, 20 parts HCl solution: 1 part cellulose) at 100°C for 30 minutes. The resulting acid-hydrolyzed cellulose is neutralized, centrifuged, and then freeze-dried.

[0142] Method 2 - Preparation of spinning solution and spinning

[0143] The cellulose obtained according to Method 1 was dissolved in 1-ethyl-3-methylimidazolium acetate at 100°C with stirring to a concentration of approximately 5% to 12%. The spinning solution was drawn into a syringe and extruded directly into a beaker of ethanol using a syringe pump through a needle (using different needle gauges: 21G, 22G, and 27G) (wet spinning). The resulting filaments were allowed to stand in ethanol for 2-3 hours and then dried in an oven at 100°C for 1 hour.

[0144] Cellulose was extracted and spinning solutions were prepared from 12 algae species according to methods 1 and 2: Ulvalactuca, Rhizoclonium, Ecklonia radiata, Eucheuma denticulatum, Kappaphycus alvarezii, Asparogopsis, Sphingomyelia, Spirulina, Scenedesmus, Phaedactylum, Chlorella vulgaris, and Chaetodon. Only fibers prepared from cellulose obtained from Chaetodon provided continuous fibers of consistent length when extruded. Fibers prepared from cellulose obtained from other algal species provided only short strands that were easily broken down and were not suitable for the testing procedure. However, thermogravimetric analysis of the Sphingomyelia fibers showed good thermal stability compared to the Chaetodon fibers ( Figure 5 ).

[0145] Microcrystalline cellulose fibers (Sigma Aldrich) and fibers of a 50:50 blend of microcrystalline cellulose and Chaetocystis-derived cellulose (obtained according to Method 1) were also prepared according to Method 2.

[0146] Method 3 - Testing of Algae Cellulose Filaments

[0147] The load-bearing capacity of fibers prepared from Chaetodon cellulose using Methods 1 and 2 was tested using magnetized weights. A fiber approximately 30 mm long was suspended by gradually increasing magnetized weights (see Figure 6). The load at which the fiber broke was recorded as the breaking load, while the load the fiber could withstand without breaking was recorded as the load-bearing capacity. The results are shown in Table 1.

[0148] Specifications and dimensions Average load capacity (g) Average breaking load (g) 21G 127.36±3.82 131.52±2.67 22G 60.69±4.41 64.33±4.04 27G 28.29±0.74 30.77±0.52

[0149] Table 1. Load-bearing capacity of regenerated Chaetoceros sclerotium cellulose fibers extruded using needles of different sizes.

[0150] The load-bearing capacity of regenerated Chaete algae cellulose fibers prepared with and without the acid hydrolysis step was compared, and the results are shown in Table 2.

[0151]

[0152] Table 2. Comparison of regenerated Chaetocystis cellulose fibers prepared with and without an acid hydrolysis step.

[0153] The tensile properties of the fibers prepared from cellulose from Chaetocystis sclerotium according to Method 1 and Method 2 were tested using a Shimadzu AGS-X electronic universal testing machine equipped with a 500N load cell according to ASTM D2256 / D2256M-21 (see Figure 7 ). According to ASTM standards, the gauge length was maintained at 250 ± 3 mm, and the test was performed at a rate of 50 mm / min on a constant rate of extension (CRE) tensile testing machine. A pre-tension of 5 ± 0.1 cN / tex was maintained to eliminate any slack or kinking in the fiber without causing significant stretching.

[0154] The gauge length before the breaking force test was started and the gauge length at the end of the breaking force test were recorded according to ASTM D2256 / D2256M-21. The elongation was defined as the gauge length at the end of the test divided by the gauge length before the test began, expressed as a percentage.

[0155] Fiber has a high aspect ratio. When comparing the tensile properties of different fibers, it is very important to eliminate the influence of fiber fineness on the breaking load. Fineness is defined as the mass of every 9000m of fiber, with tex as the unit. Take a fiber of known length, for example 80mm, and weigh it to calculate the mass of every 9000m of fiber. The resulting value is the fineness of the fiber. The breaking force obtained from the tensile test is divided by the fineness of the fiber to obtain the toughness of the fiber. The tensile and elongation test results are shown in Table 3.

[0156] Specifications and dimensions Fineness (tex) Tenacity (cN / tex) Elongation (%) 21G 107.86±0.32* 1.19±1.12* 5.68±0.78 22G 98.56±0.45* 0.64±0.89* 4.75±0.67* 27G 4.818±0.711 2.8±0.61 4.43±1.53

[0157] Table 3. Tensile and elongation test results of extruded regenerated Chaete algae cellulose fibers using needles of different sizes and a test speed of 50 mm / min. *Extrapolated values.

[0158]

[0159] Table 4. Comparison of tensile and elongation test results of regenerated Chaetocystis cellulose fibers with microcrystalline cellulose (MCC) and microcrystalline cellulose (MCC) blends. All fibers were extruded using a 21G needle, except for the fibers marked with an asterisk (*) which were obtained using a 27G needle.

[0160] Fibers made from cellulose from Chaetocystis can be processed into woven fabrics on industrial looms ( Figure 8 ).

[0161] Those skilled in the art will recognize that the disclosure described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the disclosure includes all such variations and modifications. The disclosure also includes all steps, features, compositions and compounds mentioned or indicated in this specification, whether individually or collectively, and any and all combinations of two or more of said steps, features, compositions and compounds.

Claims

1. A fiber comprising regenerated cellulose, wherein: The cellulose is obtained from algae.

2. The fiber according to claim 1, wherein The cellulose obtained from algae comprises at least about 50% w / w of the fibers.

3. The fiber according to claim 1 or claim 2, wherein The fibers consist of regenerated cellulose, wherein the cellulose is obtained exclusively from algae.

4. The fiber according to any one of claims 1 to 3, wherein The algae are algae of the genus Cladosporium.

5. The fiber according to any one of claims 1 to 4, wherein The fibers have a diameter between about 100 μm and 500 μm.

6. A method for preparing fibers comprising regenerated cellulose obtained from algae, the method comprising: (i) extracting cellulose from the algae; (ii) dissolving the cellulose in a solvent to form a spinning solution; and (iii) extruding the spinning dope into an anti-solvent to prepare the fiber.

7. The method according to claim 6, wherein: The algae are algae of the genus Cladosporium.

8. The method according to claim 6 or claim 7, wherein: Step (i) comprises treating the algae with an alkaline aqueous solution.

9. The method according to any one of claims 6 to 8, wherein Step (i) is followed by a step (ia) of hydrolyzing the cellulose with an acidic aqueous solution at elevated temperature to provide hydrolyzed cellulose.

10. The method according to claim 9, wherein: Step (ia) further comprises: neutralizing the hydrolyzed cellulose.

11. The method according to any one of claims 6 to 10, wherein Step (i) is followed by a step (ib) of removing water from the cellulose.

12. The method according to any one of claims 6 to 11, wherein The solvent is selected from the group consisting of ionic liquids, carbon disulfide, N-methylmorpholine N-oxide and copper ammonia solution.

13. The method according to any one of claims 6 to 12, wherein The solvent is an ionic liquid.

14. The method according to claim 12 or claim 13, wherein: The ionic liquid is selected from the group consisting of 1-ethyl-3-methylimidazolium acetate, 1-butyl-3-methylimidazolium chloride, 1-N-allyl-3-methylimidazolium chloride, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enyl acetate ([mTBDH][OAc]), N,N,N,N-tetramethylguanidine acetate and 1,5-diazabicyclo[4.3.0]non-5-ene ([DBNH][OAc]).

15. The method according to any one of claims 6 to 14, wherein The cellulose concentration of the spinning dope is between about 2% w / w and about 15% w / w.

16. The method according to any one of claims 6 to 15, wherein Step (iii) comprises: dry-jet wet spinning.

17. The method according to any one of claims 6 to 15, wherein Step (iii) comprises: wet spinning.

18. The method according to any one of claims 6 to 17, wherein The anti-solvent is selected from the group consisting of water, methanol, ethanol, and a mixture of two or more thereof.

19. A fabric woven or knitted from the fiber according to any one of claims 1 to 5.

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