Formulation for spinning, process for preparing a biosynthetic filament, biosynthetic fibrous product, and uses thereof

Abstract

The present invention relates to a formulation for spinning that comprises at least one polysaccharide derived from marine macroalgae, at least one alkaline agent, and optionally, at least one additive agent. Furthermore, the invention relates to the process for preparing a biosynthetic filament from the aforementioned spinning formulation, to the monofilament and / or multifilament biosynthetic fibrous product prepared by the method, and to the use of said fibrous product in the textile, medical, cosmetic, food, and other industries.

Description

“FORMULATION FOR SPINNING, PROCESS FOR PREPARING A BIOSYNTHETIC FILAMENT, BIOSYNTHETIC FIBROUS PRODUCT AND USES THEREOF” Field of Invention

[0001] The present invention relates to a spinning formulation comprising at least one polysaccharide derived from marine macroalgae, at least one alkaline agent and, optionally, at least one additive agent.

[0002] The present invention also relates to the process for preparing a biosynthetic filament from said spinning formulation, to the biosynthetic fibrous product (monofilament and / or multifilament) prepared by the method and to the use of said fibrous product in the textile, medical, cosmetic, food and other industries. Background of the Invention

[0003] Synthetic fibers are derived primarily from fossil and non-renewable resources. The total amount of synthetic fibers used worldwide is approximately 60 to 64%, of which 54 to 55% is polyester fibers. Biosynthetic fibers are an alternative to fossil-based synthetic fibers because they can be developed entirely or partially from bio-based materials.

[0004] Processes under development for the production of biosynthetic fibers include agricultural and forestry raw materials, as well as food waste. Additionally, a variety of fibers are undergoing biotechnology research, derived from raw materials such as fungi, algae, bacteria, and enzymes.

[0005] However, the industrial use of biosynthetic fibers has been limited due to problems such as quality variations, difficulty in ensuring sufficient physical properties for commercial use, and dissolution and bleaching processes involving large amounts of chemicals. Consequently, there is a need for new spinning formulations and improved processing to prepare biosynthetic fibers. REPLACEMENT SHEET (RULE 26)

[0006] Pangaia's FRUTFIBER™ product is prepared from food waste by transforming banana leaf fiber, pineapple leaf fiber and bamboo into fabric, but without using any cotton.

[0007] The German company Vitadylan has developed a fabric made from seaweed, which comes exclusively from the Icelandic fjord ecosystem, wood, and zinc. The seaweed is left completely untreated to preserve its biological value, and the process involves weaving the seaweed and zinc directly into the cellulose fiber.

[0008] US 2023 / 303725, owned by Keel Labs, describes the preparation of a polymer comprising at least one monovalent cationic alginate salt derived from seaweed; at least one C3-C20 heterosubstituted dicarboxylate; and at least one multivalent cationic crosslinking agent. The document highlights that an advantage of the invention is that products, such as fibers, can be produced using water as a solvent. For example, in wet spinning, water can be used in the spinning dope and coagulation bath. This would be advantageous from an environmental, processing, safety, and cost perspective.

[0009] Document CN 102154738 discloses a method for preparing red algae agar fiber with good biological compatibility and biological degradability for use in the clothing and medical industries. The method comprises a step of preparing an agar polysaccharide spinning solution using an aqueous solution of ethanol or DMF (dimethyl formamide) as a coagulation bath to obtain a spinnable agar fiber.

[0010] Therefore, the formulation of a spinning solution comprising bio-based raw materials with physical properties that allow its REPLACEMENT SHEET (RULE 26) industrial processing.

[0011] It is based on this scenario that the invention in question arises, a spinning formulation that comprises at least one polysaccharide derived from macroalgae, at least one alkaline agent and, optionally, at least one additive agent for preparing a regular and resistant monofilament and multifilament fibrous product. Objectives of the invention

[0012] The main objective of the invention is to provide a spinning formulation comprising a polysaccharide selected from the group comprising carrageenan, agar, alginate or a combination thereof, at least one alkaline agent and, optionally, at least one additive agent.

[0013] Furthermore, it is also an object of the invention to provide a process for preparing a biosynthetic filament from the spinning formulation comprising one or multiple coagulation bath stages.

[0014] It is also one of the objectives of the invention to provide a monofilament and multifilament fibrous product for use in the textile, medical, cosmetic, food and other industries. Summary of the Invention

[0015] The objectives discussed above are, in their entirety, achieved by the spinning formulation, by the process for preparing a filament from this formulation, by the monofilament and multifilament fibrous product and by the use of the present invention.

[0016] According to the present invention, the spinning formulation comprises a polysaccharide selected from carrageenan, agar, alginate or a combination thereof, at least one alkaline agent and, optionally, at least one additive agent. REPLACEMENT SHEET (RULE 26)

[0017] Further according to the invention, the process for preparing a filament from the spinning formulation comprises the steps of: a) preparing a spinning formulation; b) causing said spinning formulation to flow through a spinneret, thereby forming a fibrous filament; d) causing said fibrous filament to come into contact with at least one coagulation bath; and e) further subjecting the fibrous filament to at least one drawing bath.

[0018] The invention also relates to the use of the spinning formulation to prepare a biosynthetic filament for the textile industry. Brief description of the drawings

[0019] Figure 1 shows the filaments produced on the bench in the carrageenan spinning mill with the alkaline agent NaOH (4% m / v carrageenan; 4% m / v NaOH) using in the coagulation baths a) CaCh 5% (left) and 3% (right) and b) BaCh 5% (left) and 3% (right). The filaments produced using CaCh as the coagulation bath showed greater brittleness when compared to the BaCh baths.

[0020] Figures 2A-D show the coagulation bath settings for bench tests performed on a spinning mill using 4% m / v carrageenan and 4% m / v of the alkaline agent NaOH. Solutions of 10%, 5%, and 2% barium and potassium chloride and 8% ethanol were used in the coagulation baths, and optionally, a second drawing bath in 50% ethanol. The filament immersion times in each coagulation bath were standardized at 1, 2, and 5 minutes, and when using the second bath (drawing in 50% ethanol), the same time was used, so that the immersion time was the same in both baths. The tests performed on the spinning mill marked in green resulted in the best results (mechanical properties) after the filaments were dry. REPLACEMENT SHEET (RULE 26)

[0021] Figure 3 shows the filaments produced on the bench in the carrageenan spinning mill with the alkaline agent NaOH (4% m / v carrageenan; 4% m / v NaOH) using 2 baths (top photo; 1o - KCI 10% + ethanol 8% in aqueous medium, 2 o - stretching in 50% Ethanol in aqueous medium) and three coagulation baths (bottom photo; 1 o - KCI 10% + ethanol 8% in aqueous medium, 2 o - 50% ethanol in aqueous medium, and 3 o - 90% ethanol in aqueous medium). The filaments produced using only 2 coagulation baths presented filaments with superior mechanical properties to those also subjected to the third 90% ethanol bath.

[0022] Figure 4 shows the IR spectra in the middle region of the crosslinked carrageenan filament with the alkaline agent NaOH (4% m / v carrageenan; 0.33% m / v NaOH) in a 50% ethanol drawing bath (red) and in ethylenediamine / ethanol 1:20 (black). It is possible to observe the appearance of bands at 1574 cm -1 and 1460 cm -1 , referring to the symmetrical and asymmetrical stretching, respectively, of primary amines, proving the occurrence of crosslinking of the filaments.

[0023] Figure 5 shows the IR spectra in the middle region of the carrageenan filament with the alkaline agent NaOH (4% m / v carrageenan; 0.33% m / v NaOH) obtained in Wet Spinning equipment (KCl / Ethanol and Ethanol) in red and of filament obtained on the bench (KCl / Ethanol and mixture of limonene epoxides). It is possible to verify that the crosslinking of the filament in ethanolic solution of limonene epoxides is occurring, with the appearance of bands characteristic of the epoxide group, the band at 1261 cmr 1 referring to the COC stretching of epoxides and at 800 cm 1 , referring to the angular COC deformation of epoxides. The band observed at 1729 cnr 1refers to the carbonyl C=O stretching, and concerns the formation of other oxidized species of limonene, given that the separation of the limonene oxidation products from the reaction solution was not performed, as all oxidized species of limonene can crosslink with carrageenan. REPLACEMENT SHEET (RULE 26)

[0024] Figure 6 shows the IR spectra of the carrageenan filament with the alkaline agent NaOH obtained from spinning formulation A, passed through an acidic coagulation and drawing bath (black), an acidic coagulation bath (red), and an acidic crosslinking bath (green), acidified with citric acid to a pKa of 4.9. An increase in absorption of the bands at 1260 cm-1 , 1223 cm-1 , and 923 cm-1 can be observed, corresponding to the COC stretching and angular deformation of the epoxide, respectively, the latter two coinciding with the COC stretching of k-carrageenan. Therefore, the acidification of the drawing bath - alcoholic solution of limonene epoxides - improved the degree of crosslinking of the filament.

[0025] Figure 7 shows bobbins of monofilament fiber products produced on Wet Spinning equipment. The white filament is a filament prepared from Formulation H and the bath sequence: 10% KCl / 8% Ethanol; water wash; 1:20 ethanolic epichlorohydrin solution; 1:20 ethanolic cetrimonium bromide (CTAB) solution. The yellowish filament in the middle is a filament prepared from Formulation I and the bath sequence: 10% KCl / 8% Ethanol; acidified water wash; 50% ethanol. The darker filament, on the right, in the middle, is a filament prepared from Formulation I and the bath sequence: 10% KCl / 8% Ethanol and 1:20 ethanolic ethylenediamine solution.

[0026] Figures 8A to 8C show the monofilament fibrous products produced in Wet Spinning equipment. Figure 8A is a monofilament prepared from formulation J (carrageenan 9% m / v, NaOH 0.33% m / v, glycerol 2.5% m / v, and water (to 100 mL)) and the bath sequence: 10% KCl / 8% Ethanol; washing in acidified water; 50% ethanol. Figure 8B is a monofilament prepared from formulation H and the bath sequence: 10% KCl / 8% Ethanol; washing in acidified water; 1:20 epichlorohydrin ethanolic solution. Figure 8C is a monofilament prepared from formulation H and the bath sequence: 10% KCl / 8% Ethanol and 1:20 ethanolic ethylenediamine solution. REPLACEMENT SHEET (RULE 26)

[0027] Figure 9A-B shows a reel of a multifilament fibrous product produced in Wet Spinning equipment and a 26-hole die. The multifilament being prepared from formulation F9 and the bath sequence: 1) 10% KCl and 8% ethanol in water; 2) 50% ethanol; 3) 50% ethanol; 4) 95% ethanol, in which all baths had their pH maintained between 6.8 and 7.2 during processing.

[0028] Figure 10A-B shows a reel of a multifilament fibrous product produced in Wet Spinning equipment and a 26-hole die. The multifilament being prepared from formulation F9 and the bath sequence: 1) 10% KCI and 8% ethanol in water; 2) 50% ethanol; 3) 50% ethanol; 4) 95% ethanol, in which all baths had their pH maintained at ~7.

[0029] Figure 1 1AB shows a multifilament fibrous product produced in Wet Spinning equipment (filament pH ~ 9; spinning solution viscosity: 26857cP (TA)). The multifilament being prepared from formulation F4 and the bath sequence: 1) 10% KCl and 8% ethanol in water; 2) 50% ethanol; 3) 50% ethanol; 4) 95% ethanol, in which the pH acidification of all baths was performed.

[0030] Figure 12 shows a reel of a multifilament fibrous product produced in Wet Spinning equipment and a 100-hole die. The multifilament was prepared from formulation F8 and the bath sequence: 1) 10% KCI and 8% ethanol in water; 2) 50% ethanol; 3) 50% ethanol; 4) 95% ethanol, in which the pH acidification of all baths was performed.

[0031] Figure 13 shows a coil of a multifilament fibrous product produced in Wet Spinning equipment (already twisted) and a 26-hole spinneret. The multifilament being prepared from formulation F9 and the bath sequence: 1) 10% KCI and 8% ethanol in water; 2) 50% ethanol; 3) 50% ethanol; 4) 95% ethanol, in which the pH acidification of the coagulation bath was performed only, ~5.

[0032] Figure 14 shows prototypes of plain fabric produced on a rectilinear loom, from the fibrous product of Figure 13. REPLACEMENT SHEET (RULE 26)

[0033] Figure 15 shows a multifilament fibrous product produced in Wet Spinning equipment and a 26-hole die. The multifilament is prepared from formulation F9 and the bath sequence: 1) 10% KCl and 8% ethanol in water (maintained around pH 7); 2) 50% acidified ethanol; 3) 1:20 CTAB ethanolic solution; 4) 1:20 epichlorohydrin ethanolic solution.

[0034] Figure 16 shows a multifilament fibrous product produced in Wet Spinning equipment and a 26-hole die. The multifilament is prepared from formulation K and the bath sequence: 1) 10% KCl and 8% ethanol in water (pH less than 5); 2) 50% ethanol (pH ~ 5); 3) 50% ethanol (pH ~ 3); 4) 95% ethanol, without pH adjustment.

[0035] Figure 17 shows a multifilament fibrous product prepared from formulation F9 (14% w / w carrageenan and 8% w / w NaOH) and the bath sequence: 1) KCI / Ethanol, 2) 50% ethanol, 3) CTAB / ethanol 1:20 and 4) epichlorohydrin / ethanol 1:20, with coagulation bath acidulation to 6.2-6.5 and other baths ~5.

[0036] Figure 18 presents the comparative results of the multifilament fibrous products prepared from seven different spinning solutions / formulations (1 to 7), with solution 4 producing the best multifilaments since the inventors were able to reel, twist and produce the fabric from this formulation. Detailed Description of the Invention

[0037] In view of the objectives of the present invention, a spinning formulation comprising a polysaccharide selected from carrageenan, agar, alginate or a combination thereof, at least one alkaline agent and, optionally, at least one additive agent, a process for manufacturing said spinning formulation into a monofilament and multifilament fibrous product and its use is disclosed herein.

[0038] As previously mentioned, the said formulation for REPLACEMENT SHEET (RULE 26) spinning comprising a polysaccharide selected from carrageenan, agar, alginate or a combination thereof, at least one alkaline agent and at least one additive agent.

[0039] In a particular embodiment, the polysaccharide is carrageenan, preferably Lambda, Kappa, lota, Mu and Nu type carrageenan, even more preferably kappa carrageenan.

[0040] In one embodiment of the invention, the at least one alkaline agent is an aqueous alkaline solution. An aqueous alkaline solution is a solution of any base that forms hydroxide ions upon dissolution in water, including basic salts of alkali metals and alkaline earth metals, as well as ammonia.

[0041] In a particular embodiment of the invention, the at least one alkaline agent is selected from the group comprising sodium hydroxide, potassium hydroxide and combinations thereof.

[0042] In one embodiment of the invention, the at least one additive agent is an agent for improving the physical and mechanical characteristics of the fibrous product to be formed.

[0043] In a particular embodiment of the invention, the at least one additive agent is selected from the group comprising starch, glycerol, castor oil, polyethylene glycol-400 (PEG-400), carboxymethyl cellulose (CMC), sorbitol, bixin, norbixin, bixin / norbixin mixture, lignin, lignocellulosic residue, creatine, triacetin, citric acid, agar, sodium alginate, urea, blueberry and grape pigments, cetrimonium bromide (CTAB) and combinations thereof.

[0044] In one embodiment of the invention, an aqueous vehicle constitutes a significant portion of the spinning formulation. The aqueous vehicle is selected from the group comprising purified water, deionized water, distilled water, and combinations thereof. REPLACEMENT SHEET (RULE 26)

[0045] In a particular embodiment of the invention, the spinning formulation is in a liquid or gel state.

[0046] In a preferred embodiment of the invention, the spinning formulation comprises: the polysaccharide in an amount of 1% to 20% by weight, preferably 3.8% to 15% by weight; an alkaline agent in an amount of 0.1% to 10% by weight, preferably 0.1% to 8% by weight; optionally, an activating agent in an amount of 0.01% to 6% by weight, preferably 0.01% to 5% by weight; and an aqueous vehicle in an amount of 75% to 95% by weight, preferably 77% to 94% by weight; based on the total volume of the formulation.

[0047] In another embodiment of the invention, the spinning formulation is extruded or spun through a die or spinneret to prepare or form filaments of a fibrous product, particularly the spinning process employs wet spinning.

[0048] In one embodiment of the invention, the process for preparing a filament from the spinning formulation comprises the steps of: a) preparing a spinning formulation; b) causing said spinning formulation to flow through a spinneret, thereby forming a fibrous filament; d) causing said fibrous filament to come into contact with a coagulation bath; and e) further subjecting the fibrous filament to a drawing bath. REPLACEMENT SHEET (RULE 26)

[0049] In one embodiment of the invention, the coagulation bath comprises a solution selected from the group comprising water, ethanol, CaCh, BaCh, KCl, and combinations thereof.

[0050] In another embodiment of the invention, the drawing / crosslinking bath comprises a solution selected from the group comprising water, ethanol, ethylenediamine, D-limonene epoxide, mixture of limonene epoxides, bisphenol A diglycidyl ether, epichlorohydrin, cetrimonium bromide (CTAB), lignocellulosic residue, lignin, triacetin, citric acid, agar, sodium alginate, urea, blueberry and grape pigments, eucalyptus oil and combinations thereof.

[0051] In one embodiment of the invention, in order to improve the degree of crosslinking of the filament, the coagulation and / or drawing baths can be subjected to an adjustment of the pH of the solution, preferably to acidification, for example, using 37% HCI and / or CO2 (bubbled).

[0052] In a particular embodiment of the invention, said process further comprises subjecting the fibrous filament to a washing bath, preferably acidified washing in acidified water or acidified ethanol (e.g. 50% ethanol).

[0053] In another particular embodiment of the invention, the coagulation bath is a single-stage coagulation bath or a multi-stage coagulation bath.

[0054] In a preferred embodiment of the invention, the coagulation bath is a multi-stage bath, wherein said process comprises up to ten coagulation bath stages.

[0055] In a particular embodiment of the invention, the first coagulation bath does not comprise ethanol.

[0056] In one embodiment of the invention, the use of the spinning formulation is REPLACEMENT SHEET (RULE 26) to prepare a monofilament and / or multifilament fibrous product.

[0057] The present invention is described below with reference to the following examples, which are not intended to limit the scope of the present invention in any way.

[0058] To provide a more complete understanding of the modalities described here, the following examples are presented. It should be understood that these examples are for illustrative purposes only and should not be construed as limiting. Example 1: Formulation for spinning according to the invention

[0059] In a preferred embodiment, the spinning formulation of the present invention comprises the components of Tables A to G below. Table A - Exemplary formulation for spinning A *in a volume of 100 ml_ Table B - Exemplary formulation for spinning B *in a volume of 100 ml_ REPLACEMENT SHEET (RULE 26) Table C - Example formulation for spinning C *in a volume of 100 ml_ Table D - Example formulation for spinning D *in a volume of 100 ml_ Table E - Exemplary formulation for spinning E *in a volume of 100 ml_ Table E1 - Example formulation for E1 spinning REPLACEMENT SHEET (RULE 26) *in a volume of 100 mL Table E2 - Example formulation for E2 spinning *in a volume of 100 mL Table E3 - Example formulation for E3 spinning *in a volume of 100 mL Table E4 - Example formulation for E4 spinning *in a volume of 100 mL Table E5 - Example formulation for E5 spinning *in a volume of 100 mL REPLACEMENT SHEET (RULE 26) Table E6 - Example formulation for E6 spinning *in a volume of 100 ml_ Table F1 - Example formulation for spinning F1 *in a volume of 100 ml_ Table F2 - Example formulation for spinning F2 *in a volume of 100 ml_ Table F3 - Example formulation for spinning F3 *in a volume of 100 ml_ REPLACEMENT SHEET (RULE 26) Table F4 - Example formulation for spinning F4 *in a volume of 100 ml_ Table F5 - Example formulation for spinning F5 *in a volume of 100 ml_ Table F6 - Example formulation for spinning F6 *in a volume of 100 ml_ Table F7 - Example formulation for spinning F7 *in a volume of 100 ml_ REPLACEMENT SHEET (RULE 26) Table F8 - Example formulation for spinning F8 *in a volume of 100 ml_ Table F9 - Example formulation for spinning F9 *in a volume of 100 ml_ Table F10 - Example formulation for spinning F10 *in a volume of 100 ml_ Table F11 - Example formulation for spinning F11 *in a volume of 100 ml_ REPLACEMENT SHEET (RULE 26) Table G - Example formulation for spinning G *in a volume of 100 ml_ Table H - Example formulation for H spinning *in a volume of 100 ml_ Table I - Exemplary formulation for spinning I *in a volume of 100 ml_ REPLACEMENT SHEET (RULE 26) Table J - Example of the J-spinning formulation *in a volume of 100 ml_ Table K - Example formulation for K spinning *in a volume of 100 mL Example 2: Preparation of wiring solutions - Preparation of spinning formulations A-E6

[0060] Spinning formulations A-E6 of Example 1 were prepared following the process below.

[0061] To prepare 100 mL of spinning solution, add the alkaline agent, NaOH, and optionally the lignocellulosic residue to a 250 mL beaker containing 100 mL of MiliQ or distilled water. The mixture is stirred constantly at 50°C for 30 minutes to break down part of the lignocellulosic residue structure, followed by the addition of the polysaccharide and additive. This system is kept under constant stirring at 70°C for 2 h. REPLACEMENT SHEET (RULE 26)

[0062] The AE solutions were capable of producing monofilaments, but still had viscosities of up to 30,000 cP and the need for very high spinning temperatures (70-80°C), at the limit of the pilot Wet Spinning equipment. - Preparation of spinning formulations F1 - F1 1

[0063] Spinning formulations F1-F11 of Example 1 were prepared following the following process.

[0064] To prepare 100 mL of spinning solution F1 - F1 1: in a 250 mL beaker containing 100 mL of MilliQ or distilled water, add the alkaline agent, NaOH, and heat the mixture to 70°C, followed by the addition of the polysaccharide and, optionally, the additive. After the polysaccharide has been completely added, the solution is kept at 70-80°C for 2 hours with stirring. - Spinning formulations with additives

[0065] In order to improve the physical and mechanical characteristics of carrageenan filaments, the inventors also evaluated the incorporation and combination of additives such as starch, glycerol, castor oil, polyethylene glycol-400 (PEG-400), carboxymethyl cellulose (CMC), sorbitol, bixin / norbixin mixture, lignocellulosic residue, triacetin, agar and creatine.

[0066] A spinning formulation containing: 6.84% m / m carrageenan powder, 1.709% m / m CMC, 1.709% m / m starch and 4.27% m / m glycerol in 100 mL of distilled water was prepared. The produced filaments passed through the coagulation baths of KCI 10% + Ethanol 8% (1) and Ethanol 50% (2) in aqueous medium, showing themselves to be resistant, but very brittle.

[0067] A spinning formulation containing carrageenan powder, NaOH, and glycerol in 100 ml of water was prepared (4% w / v carrageenan; 0.30% w / v NaOH; 2.5% w / v glycerol | 3.75% w / w carrageenan, 0.281% w / w NaOH, 2.341% w / w glycerol). REPLACEMENT SHEET (RULE 26)

[0068] The solution was observed to gel quickly but was not very viscous. The carrageenan filament containing only glycerol as an additive was transparent and shiny when wet and opaque and yellowish when dry.

[0069] Another spinning formulation was prepared having 0.04% m / v NaOH, 0.5% m / v carrageenan, 0.5% m / v PEG-400 (3.96 x 10' 4 % w / w NaOH, 0.495% w / w carrageenan, and 0.495% w / w PEG) in 100 ml of water. The solution was kept under constant stirring and heating, between 50-60 °C for 1 h 10 min, resulting in a light yellow, very viscous solution. Filaments were produced after 1 h 30 min and 2 h 13 min of reaction, with the 2-h filaments being more resistant. Furthermore, the inclusion of castor oil in this same formulation was evaluated, and the final fiber was shown to be very fragile when dried at room temperature.

[0070] Two spinning formulations containing sorbitol as an additive agent were prepared with 0.1 g of NaOH and 2 g of carrageenan each in 100 mL of water, to which the following additive agents were added: 1) 20% m / v (20 g) of sorbitol and 1.5 g of glycerol and 2) 2% m / v (2 g) of sorbitol and 1.75 g of glycerol. From the first formulation (0.08% m / m NaOH, 1.618% m / m carrageenan, 16.18% m / m sorbitol and 1.21% m / m glycerol) it was not possible to produce filaments and the second formulation (0.09% m / m NaOH, 1.9% m / m carrageenan, 1.9% m / m sorbitol and 1.65% m / m glycerol) produced very brittle filaments.

[0071] Another spinning formulation was prepared containing 0.009% w / w NaOH, 3.74% w / w carrageenan, 0.009% w / w lignocellulosic residue, 2.34% w / w glycerin, and 0.47% w / w urea in 100 ml of water. This solution was kept under stirring at 70°C for 2 h and spun in baths of 10% KO1 / 8% ethanol (aqueous medium) and 50% ethanol. The filaments of this preparation proved to be very fragile. Example 3: Preparation of coagulation and stretching baths -Coagulation baths REPLACEMENT SHEET (RULE 26)

[0072] The inventors of the present invention evaluated the best coagulation baths for the wet spinning process using solutions of barium, calcium, and potassium chlorides (10%, 5%, 3%, and 2%) and ethanol (8%, 50%, 90%, and 100%). The filaments were immersed in each of the coagulation baths for 1, 2, and 5 minutes.

[0073] Wet spinning for monofilament preparation was carried out on DIENES equipment, using 1 liter of the spinning formulation with the parameters in Table 1. Table 1 - Wet spinning parameters Pressure 2 bar Solution temperature 70 °C Block temperature 70°C wiring Pump speed 1-3 mL / min Drawing speeds 1.2 to 8.76 m / min

[0074] It should be noted that the filaments produced using 5% and 2% CaCh as the coagulation bath showed greater fragility when compared to the BaCh baths (see Figure 1). Figures 2A to 2D show the comparison between the coagulation baths, in which the tests performed in the spinning mill (mechanical tests (tensile strength to break) and swelling and solubilization in water and humidity of the filament after drying), in green, show the best results after the filaments were dry.

[0075] Tests containing three coagulation baths were also carried out: 1) 10% KCl + 8% ethanol in aqueous medium, 2) 50% ethanol in aqueous medium, and 3) 90% ethanol in aqueous medium. The filaments produced using only 2 coagulation baths: 1) 10% KCl + 8% ethanol (aqueous medium) and 2) 50% ethanol (aqueous medium) presented filaments with superior mechanical properties to those also subjected to the third 90% ethanol bath (Figure 3). - Drawing baths REPLACEMENT SHEET (RULE 26)

[0076] The best drawing baths for the wet spinning process were also evaluated using solutions of ethylenediamine / ethanol (in a ratio of 1:20); D-limonene epoxide / ethanol; bisphenol A diglycidyl ether / ethanol (1:20); eucalyptus oil / ethanol (1:20). The immersion time of the filaments in each of the drawing baths in the bench tests was 1 minute.

[0077] In order to verify the occurrence of crosslinking of the filaments subjected to the drawing bath, FTIR analyses were performed to compare the spectra of the crosslinked filament (Figures 4 to 6). Example 4 - Tests with the combination of polysaccharides

[0078] The inventors also carried out three tests containing the polysaccharides carrageenan, agar and alginate.

[0079] The first test was performed with spinning formulation G. After 2 hours of reaction at 70°C, the spinning solution was still not very viscous, and filaments could not be formed in a 10% KCl or 10% BaCl2 aqueous solution. Therefore, 1 ml of a 10% BaCl2 aqueous solution was added to the spinning solution. This solution was then spun in coagulation solutions containing: a) 10% KCl aqueous solution; b) 10% BaCl2 aqueous solution; and c) 10% KCl / 8% ethanol aqueous solution. The best filament coagulation occurred in the following order: c, b, and a, although all produced very fragile filaments. After defining the best coagulation solution, c, solutions for a second bath were tested, containing: a) 50% ethanol; b) ethanolic solution of ethylenediamine, 20:1 and c) ethanolic solution of bisphenol A diglycidyl ether, 20:1. All attempts produced very fragile filaments.

[0080] The second test was performed by preparing a spinning solution containing a combination of the polysaccharides agar, carrageenan, and sodium alginate in a 1:1:1 ratio, which together totaled a 4% w / v solution in water. Additives of 2.5% w / v glycerol, 0.33% w / v NaOH, and 0.01% w / v lignocellulosic residue were added. Unlike the test with Formulation G, this spinning solution REPLACEMENT SHEET (RULE 26) The combination of polysaccharides (0.31% w / w NaOH, 1.24% w / w polysaccharides of each, and 2.34% w / w glycerol) proved to be quite viscous after stirring for 2 hours at 70°C, and it was possible to obtain coagulated filaments in a 10% KCl / 8% ethanol aqueous solution. However, outside this solution, the filaments fell apart. An important fact is that even at room temperature, the spinning solution does not solidify, always remaining viscous.

[0081] It is concluded that the additives and improvements developed for the solution containing only carrageenan should not be the same for spinning solutions containing other polysaccharides, thus requiring improvement of routes for their inclusion.

[0082] Since this project focuses on developing filaments containing a majority of carrageenan, a test 3 was conducted using agar as an additive. To obtain a multifilament, a test was performed to increase the viscosity of the spinning solution by increasing gel strength. To this end, 1% agar was added to the 9% carrageenan solution to increase gel strength without increasing the sulfate content, which is present in carrageenan and makes the filament water-soluble. The spinning solution used was composed of 9% w / v carrageenan, 1% w / v agar, 0.33% w / v NaOH, and 2.5% w / v glycerol in water. Coagulation solution: KCl / ethanol, and drawing solution: 50% ethanol. However, the filament formed was very fragile and broke upon exiting coagulation. Example 5 - Mechanical, Viscosity and Swelling Tests in Water

[0083] Elongation, tenacity, and elastic modulus tests were performed on dry fibers produced from the spinning formulations of the present invention (10 specimens of each fiber), using an Autodyn II Automatic 2514 equipment, with a distance between grippers of 100 mm or 150 mm and a mobile gripper separation speed of 90 mm / min. Viscosity tests were performed using a First Touch viscometer (Lamy Rheology Instruments). The tests were REPLACEMENT SHEET (RULE 26) carried out using spindle No. 5 (approximately 19 mm in diameter and 65 mm in length) at 30 rpm.

[0084] The AE solutions were able to produce monofilaments, but still had viscosities of up to 30,000 cP and the need for very high spinning temperatures (70-80°C), at the limit of the pilot Wet Spinning equipment.

[0085] For multifilament, we must work with drawing speeds between 2 and 3 mL / min and temperatures between room temperature and 50°C, depending on the carrageenan concentration. Currently, the formulation that produced the best multifilaments (the inventors were able to reel, twist, and produce the fabric) was Formulation F9 (14% carrageenan and 8% NaOH), as can be seen in Figure 18.

[0086] Having described the embodiments of the spinning formulation, use and manufacturing process, it should be understood that the scope of protection in question also covers variations not described, but derived or equivalent. REPLACEMENT SHEET (RULE 26)

Claims

CLAIMS 1. Spinning formulation CHARACTERIZED by the fact that it comprises: a polysaccharide selected from carrageenan, agar, alginate or a combination thereof; at least one alkaline agent; optionally, at least one additive agent; and an aqueous vehicle.

2. Spinning formulation according to claim 1, CHARACTERIZED by the fact that the alkaline agent is selected from the group comprising sodium hydroxide, potassium hydroxide and combinations thereof.

3. Spinning formulation according to claim 1 or 2, CHARACTERIZED by the fact that the additive agent is selected from the group comprising starch, glycerol, castor oil, polyethylene glycol-400 (PEG-400), carboxymethyl cellulose (CMC), sorbitol, bixin, norbixin, bixin / norbixin mixture, lignocellulosic residue, creatine, triacetin, citric acid, agar, sodium alginate, urea, blueberry and grape pigments, cetrimonium bromide (CTAB) and combinations thereof.

4. Spinning formulation according to any one of claims 1 to 3, further comprising: a polysaccharide in an amount of 1% to 20% by weight; an alkaline agent in an amount of 0.1% to 10% by weight; optionally, an activating agent in an amount of 0.01% to 6% by weight; based on the total volume of the formulation.

5. Process for preparing a filament from the spinning formulation as defined in any one of claims 1 to 4, CHARACTERIZED by the fact that the process comprising the steps: REPLACEMENT SHEET (RULE 26) a) preparing a spinning formulation as defined in any one of claims 1 to 4; b) causing said spinning formulation to flow through a spinneret, thereby forming a fibrous filament; d) causing said fibrous filament to come into contact with a coagulation bath; and e) further subjecting the fibrous filament to a drawing bath.

6. The process of claim 5, wherein the coagulation bath is a multi-stage coagulation bath.

7. Process, according to claim 5 or 6, CHARACTERIZED by the fact that step (b) comprises up to five coagulation bath stages.

8. Process according to any one of claims 5 to 7, CHARACTERIZED by the fact that the coagulation bath comprises a solution selected from the group comprising water, ethanol, CaCh, BaCh, KCl and combinations thereof.

9. Process according to any one of claims 5 to 8, CHARACTERIZED by the fact that the drawing bath comprises a solution selected from the group comprising water, ethanol, ethylenediamine, D-limonene epoxide, bisphenol A diglycidyl ether, epichlorohydrin, cetrimonium bromide (CTAB), lignocellulosic residue, lignin, triacetin, citric acid, agar, sodium alginate, urea, blueberry and grape pigments, eucalyptus oil and combinations thereof.

10. Process according to any one of claims 5 to 9, further comprising subjecting the coagulation and / or drawing baths to an adjustment of the pH of the solution.

11. Fibrous product CHARACTERIZED by the fact that it is prepared by the method, as defined in any one of claims 5 to 10.

12. Use of the spinning formulation as defined in any of the REPLACEMENT SHEET (RULE 26) claims 1 to 4 and the fibrous product as defined in claim 11, CHARACTERIZED by the fact that it is used as fiber in the textile, medical, cosmetic, food or similar industry. REPLACEMENT SHEET (RULE 26)

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