TW201335450A - Manufacturing method for natural cellulose fiber having flame resistant function - Google Patents

Abstract

This invention provides a manufacturing method for natural cellulose fiber having flame resistant function comprising steps: mixing wood pulp and N-methylmorpholine N-oxide (NMMO) solvent into slurry; removing water content through a vacuum thin film evaporator (TFE) to form a spinning dope; squeezing the spinning mucus from a spinneret by adopting dry-jet wet spinning manner; then performing pad-roll with N-hydroxymethyl-3 (two methoxy phosphorus acyl) propionamide flame retardant after processing with coagulation bath regeneration, water rinsing and drying, sequentially imposing drying, roasting, neutralizing, soap washing, water rinsing, and drying, and obtaining a natural cellulose fiber having long duration of flame resistant function after finally performing with procedures of caustic wash, water rinsing, and drying and oiling. In the manufacturing process, the natural cellulose fiber generates specific crosslink reaction together with the N-hydroxymethyl-3 (two methoxy phosphorus acyl) propionamide flame retardant. Its flame resistant efficacy fully satisfies United States ASTM D6413-1999 and ASTM D2863-1995 test standards. After using and disposing it, the natural cellulose fiber can be decomposed naturally to form an environmental friendly material without harming natural environments.

Description

Process for producing natural cellulose fibers with flame resistance

The invention relates to a "method for producing natural cellulose fibers with flame resistance function", which belongs to the technical field of manufacturing green fibers, which is N-hydroxymethyl-3-(dimethoxyphosphonium) propyl hydrazine. The amine flame retardant is impregnated, dried, baked, neutralized, soaped, washed with water and dried to make the active N-methylol react with the natural cellulose fiber, and then washed by alkali. After washing, drying, oiling and coiling, natural cellulose fibers with long-lasting flame resistance can be produced.

The flame-resistant fiber method currently used for fire-resistant flame-resistant fabrics or fabrics is made by mechanically uniformly mixing polypropylene clear fibers and polyamide fibers, for example, as shown in Taiwan Invention Certificate No. I248488, or directly in multiple bundles. Polypropylene fine fiber is produced by rolling traction and heating in a rolling step, for example, as shown in Taiwan Invention Bulletin No. 182661, or by adding a flame retardant to a polyolefin, such as Taiwan Invention Announcement No. 191223. In addition, in addition, in order to achieve a more economical manufacturing cost, but the flame-resistant effect is inferior, the flame retardant is directly coated on the surface of the various synthetic fibers described above to achieve a flame retardant effect.

However, all of the above-mentioned flame-resistant fibers are non-dissolving fibers. After use, the wastes cannot be naturally degraded and harmful to the natural environment. As countries have successively formulated textile flammability technical regulations, if the products do not meet the requirements of these regulations, they will be Preventing the entry into the country's market, therefore, the demand for textiles with flame retardant properties is constantly increasing, but at the same time it also leads to a large increase in non-dissolved fiber waste and a greater harmful burden on the natural environment. In addition, Some of them are resistant to flammability or surface coating to achieve their flame resistance. Although they are relatively low in manufacturing cost, their flame resistance is relatively poor. Instead, they pose a concern for home safety or human safety.

In view of this, how to produce a natural cellulose fiber with a long-lasting flame-resistant function by producing a special cross-linking reaction of natural cellulose fibers (ie, soluble fibers) that do not harm the natural environment under the set process conditions, Urgently urgent and need.

The main object of the present invention is to provide a "method of producing natural cellulose fibers having a flame-resistant function" by mixing a wood pulp with a solvent of N-methylmorpholine N-oxide (NMMO) to form a slurry. The water is removed by a Thin Film Evaporator (TFE) to form a dope, and the Dry-Jet Wet Spinning method is used to squeeze the spinning mucus from the spinning nozzle. It is made into a natural cellulose fiber after being regenerated by a coagulation bath, washed with water and dried, and then impregnated with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant. The order is applied to drying, baking, neutralizing, soaping, washing and drying, and finally, after alkali washing, washing and drying, and oiling, natural cellulose fiber with long-lasting flame resistance can be obtained. The natural cellulose fiber of the flame-resistant function can produce a special cross-linking reaction with the N-hydroxymethyl-3-(dimethoxyphosphonium)-propionamide flame retardant in the process, after 50 times of water washing treatment, The flame-resistant function of the fiber still maintains the effect before the original water wash, and fully conforms to the American ASTM D641. 3-1999 and ASTM D2863-1995 test standards, and their use can be naturally decomposed after disposal, and become an environmentally friendly material for a harmless natural environment.

Another object of the present invention is to provide a method for preparing a natural cellulose fiber having a flame-resistant function, and a method for recovering and regenerating a solvent in a process thereof is to use a streamlined and effective equipment and four processes such as decolorization, filtration, concentration, and refining. The main procedure is to recover the washing liquid into a oxidized methyl marlin (NMMO) solvent of the same quality as the fresh solvent, and the loss rate is below 0.5%, and the total recovery rate is over 99.5%, except that it does not pollute the environment. In addition, it is more effective in reducing the cost of solvent recovery, and has the economic mass production benefit of clean production and resource recycling.

In order to further illustrate the production process and efficacy of the present invention, the following is a detailed description of the examples and test examples:

Referring to the first to third figures, the "manufacturing method of natural cellulose fiber with flame resistance function" of the present invention comprises the following steps:

(a). Mixing wood pulp with N-methylmorpholine N-oxide (NMMO) solvent to form a slurry, and incorporating 1,3-phenylene-bis 2-oxazoline , BOX) stabilizer, and using a horizontal pulper, the above wood pulp, oxidized methyl marlin (NMMO) solvent and phenyloxazole stabilizer are placed together, and then at a low temperature of 60 ° C ~ 80 ° C together The pulp is selected from the group consisting of long fibers or short fibers having a cellulose content of 85% or more, and the cellulose degree of polymerization (DP) is 500 to 1200. The concentration of the oxidized methyl marlin (NMMO) is 50% to 75%, and the chemical structure diagram thereof is as shown in the second figure;

(b). Evaporate excess water using a Thin Film Evaporator (TFE), heat at 80 ° C to 120 ° C, remove moisture to 5% to 13% in 5 minutes, and dissolve the cellulose into a spinning Silky mucus (dope);

(c) spinning by dry-jet spinning method (Dry-Jet Wet Spinning), extruding the spinning mucilage from the spinning nozzle, and then entering the coagulation bath to solidify and re-form the filament;

(d). The solidified regenerated spun yarn is washed with water and dried to form a natural cellulose fiber, wherein the drying temperature is 100 ° C to 130 ° C, and the time is 3 to 5 seconds;

(e). The natural cellulose fiber is impregnated with a N-methylol-3-(dimethoxyphosphonium) acrylamide flame retardant, and the rolling rate is 65% to 70%, and the N-hydroxyl The concentration of the methyl-3-(dimethoxyphosphonium)propionamide flame retardant is from 250 g/L to 500 g/L, and the chemical structure diagram thereof is as shown in the third figure;

(f). The natural cellulose fibers after padding are sequentially dried, baked, neutralized, soaped, washed and dried; wherein the drying temperature is 105 ° C and the drying time is 10 In seconds, baking is carried out twice. The baking temperature of the first baking is 130 ° C ~ 155 ° C, the baking time is 60 seconds - 120 seconds, then the baking temperature of the second baking is 165 ° C ~ 180 ° C, baking time is 60 In seconds to 120 seconds, the concentration of the alkali solution used for the neutralization is 50 g/L, the neutralization temperature is 20 ° C to 30 ° C, the concentration of the alkali solution used for the soaping is 2 g / L, and the soap powder used for the soaping is 3 g. /L, the soaping temperature is 20 ° C ~ 30 ° C, the soaping time is 10 seconds; and

(g). Finally, after alkali washing, washing and drying procedures and oiling, natural cellulose fibers having long-lasting flame resistance can be obtained, and the growth fibers can be taken up according to the desired form of the product, or Cut into short fibers according to the length specification; wherein the alkali washing used is NaOH or Na ₂ CO ₃ , the winding speed is 200-600 meters per minute, and the fiber strength of the obtained fiber is 3.0 g/ d～5.0g/d, the fiber elongation is 4.0% to 8.0%, and the fiber Young's modulus is 50g/d to 150g/d.

In the above step (a), the phenyloxazole stabilizer is incorporated by adding, for example, a phenyloxazole (500, 2,500 ppm) in a solvent of oxidized methylmaline (NMMO). -phenylene bis-2 oxazoline), and then blended with wood pulp to form a slurry, as shown in the following list (A):

The phenyloxazole stabilizer used in the present invention is more effective than the conventional sodium hexametaphosphate (SHMP) stabilizer and n-proply gallate (PG) stabilizer. With less coloring, the coloring index is 470nm, and the spectrophotometer transmittance index is reduced from 51.1 to 10.2, as shown in the following list (B), so the solvent recovery and refining procedure can be simplified and the solvent recovery rate can be improved; and the unit price is also better than the conventional additive. It is much cheaper and helps to reduce solvent costs, as shown in the following list (C).

In addition, in the above process of the present invention, the main solvent oxidized methylmarine (NMMO) is released during the fiber regenerated water washing in the step (d), and since the amount is extremely large, it must be completely recovered for full recycling, and the solvent is recovered. As shown in the first figure, it contains:

A. Decolorization: adsorption decolorization by activated carbon suspension method, adding 0.05% to 0.10% of activated carbon powder with good adsorption and suspension property to the decolorization liquid, and alternately treating with blast mixing and reconstitution and static suspension adsorption. The processing time ratio of the two is 1:3 to 1:6, and the processing time is more than 8 hours to complete the decolorization. This method and program can simplify the equipment, save energy and improve the adsorption decolorization effect.

B. Filtration: Two-stage filtration is adopted. The first stage coarse filtration uses a general filter-type filter to simplify the equipment, but in order to avoid the accumulation of activated carbon in the outermost layer of the filter element and slow down the filtration speed, the filter aid is pre-coated. In addition to the surface of the filter element, 0.03% to 0.05% is also added to the unfiltered filtrate, so that the filtrate does not contain a small amount of bulking filter aid, and the filtration rate is greatly improved and can be maintained without any decrease. The filter aid is composed of diatomaceous earth: The ratio of cellulose=4:1 is the best. After the coarse filtration is completed, the residual residue of the residue is centrifuged, dehydrated and recovered, and the filter residue of the dewatered filter residue can still be recycled once. The second stage of fine filtration uses the precision filter UF. The fineness of the filtrate after fine filtration is the same as that of fresh solvent. The coarse filtration and fine filtration of this method have the advantages of low equipment cost, low loss rate, high throughput and high purity. .

C. Concentration: When the process of the invention is recovered by the washing liquid, the solvent concentration needs to be concentrated from 6.5% to 8.0% to 50% to 55%, and about 90 tons of water per ton of concentrated water is required, and the concentration load is extremely large; Less time: It adopts three-effect concentration method, which requires about 0.5 tons of steam per ton of water (although the steam consumption is high, but the power consumption is small); when the fiber yield is slightly larger: the MVR concentration method is used to remove water. About 0.003 to 0.03 tons of steam per ton (although the steam consumption is low, but the power consumption is slightly larger), the two concentration methods are applicable to different yields, but the concentrated liquid and condensed water produced can be completely recovered; The liquid can be used for the solvent of the process, and the condensed water can be used for washing the raw silk.

D. Refining: using 80 ° C low temperature oxidation and neutralization reduction, using 35% H ₂ O ₂ as oxidant, 85% N ₂ H ₄ ‧H ₂ O as a neutralizing reducing agent, the result of redox determination by potentiometric titration The oxidized methyl marlin (NMMO) content can be reduced to less than 10 ppm, and the purity of the oxidized methyl marlin (NMMO) can be improved and the loss can be reduced.

In order to further understand the efficacy of the present invention, according to the process of the present invention, different components, conditions and parameters are set, and the following examples of the tests are completed, and the following are explained in detail:

Example 1 (sample numbers D1 to D12 and F1 to F12 of the present invention):

Mixing wood pulp cellulose with a degree of polymerization of 650 with oxidized methyl marlin (NMMO) solvent to form a slurry, and incorporating 1,3-phenylene-bis 2-oxazoline (BOX) in different proportions Then, use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, then dissolve the cellulose into a dope, the composition of the mucus [Table 1] The sample numbers are shown in D1 to D12, and the mucus is sent to a spinning machine for spinning by metering pump, and extruded by a spinning method in a push-out manner. Dry-jet spinning method (Dry-jet) Wet Spinning) is regenerated by a coagulation bath, washed with water and dried to form natural cellulose fibers, and the natural cellulose fibers are immersed with N-hydroxymethyl-3-(dimethoxyphosphonium) propylene amide flame retardant. Rolling, the rolling rate is 65% to 70%, the N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide flame retardant concentration is 0g / L ~ 450g / L, the baking temperature is 180 °C, baking time is 240 seconds, then the fiber is neutralized, soaped, washed, dried, then alkali washed, washed, dried, oiled and coiled to make natural fiber with flame resistance Su long filaments, a fiber sample as obtained above [Table II] Sample No. F1 ~ F12 in FIG.

Example 2 (sample numbers D13 to D24 and F13 to F24 of the present invention):

Mixing wood pulp cellulose with a degree of polymerization of 1050 with oxidized methyl marlin (NMMO) solvent to form a slurry, and incorporating 1,3-phenylene-bis 2-oxazoline (BOX) in different proportions Then, use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, then dissolve the cellulose into a dope, the composition of the mucus [Table 1] The sample numbers are shown in D13~D24, and the mucus is sent to the spinning machine for spinning by metering pump, and extruded by the spinning port by extrusion. Dry-jet spinning method (Dry-jet) Wet Spinning) is regenerated by a coagulation bath, washed with water and dried to form natural cellulose fibers, and the natural cellulose fibers are immersed with N-hydroxymethyl-3-(dimethoxyphosphonium) propylene amide flame retardant. Rolling, the rolling rate is 65% to 70%, the N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide flame retardant concentration is 0g / L ~ 450g / L, the baking temperature is 180 °C, baking time is 240 seconds, then the fiber is neutralized, soaped, washed, dried, then alkali washed, washed, dried, oiled and coiled to make natural fiber with flame resistance The vegetal filaments are obtained, and the fiber samples obtained above are shown in the sample numbers F13 to F24 in [Table 2].

Example 3 (flame resistance test):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with an oxidized methyl marlin (NMMO) solvent to form a slurry and incorporated with a 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer. Then use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, you can dissolve the cellulose into a dope, and then measure the mucus The pump is sent to a spinning machine for spinning, extruded through a spinning port by extrusion, and regenerated by a dry-jet wet spinning method (Dry-jet Wet Spinning), and then washed and dried to form natural cellulose. a fiber, which is padded with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and has a rolling rate of 65% to 70%, and the N-hydroxyl group The concentration of the base-3-(dimethoxyphosphonium)propionamide flame retardant is from 0g/L to 450g/L, the baking temperature is from 130°C to 180°C, the baking time is from 120 seconds to 240 seconds, and then the fiber is neutralized. After washing with soap, washing with water, drying, washing with alkali, washing with water, drying, oiling and coiling, the natural cellulose filament having the flame resistance function of the present invention is obtained, and the fiber samples obtained above are obtained. According to the American ASTM D6413-1999 test standard, various flame resistance tests were carried out.

The flame resistance test adopts the vertical combustion method, and the fibers of the samples F1 to F24 of the present invention are respectively woven into three pieces of fabric, each piece of 1.5 cm×24.5 cm, and the sample is fixed on the fire tester so that the lower end of the sample is 19 mm away from the lamp socket. And adjust the flame height of 38 mm, contact the sample for 12 seconds, remove the flame, and press the stopwatch until the enamel is completely extinguished and then stop the watch, record the afterflame time and the ember time.

Carbonization distance measurement; after the end of the above-mentioned flame resistance test, each sample is taken and folded in half. A weight corresponding to the unit area of the sample is pressed on the lower end side of each sample, and each sample is slowly lifted by hand. On the other side of the lower end, the weight is turned over and the length of the sample is broken. The various test results obtained above are shown in sample numbers F1 to F24 in [Table 3] and in sample numbers T1 to T24 in [Table 4].

Example 4 (Oxygen limit index flame resistance test):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with an oxidized methyl marlin (NMMO) solvent to form a slurry and incorporated with a 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer. Then use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, you can dissolve the cellulose into a dope, and then measure the mucus The pump is sent to a spinning machine for spinning, extruded through a spinning port by extrusion, and regenerated by a dry-jet wet spinning method (Dry-jet Wet Spinning), and then washed and dried to form natural cellulose. a fiber, which is padded with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and has a rolling rate of 65% to 70%, and the N-hydroxyl group The concentration of the base-3-(dimethoxyphosphonium)propionamide flame retardant is from 0g/L to 450g/L, the baking temperature is from 130°C to 180°C, the baking time is from 120 seconds to 240 seconds, and then the fiber is neutralized. After washing with soap, washing with water, drying, washing with alkali, washing with water, drying, oiling and coiling, the natural cellulose filament having the flame resistance function of the present invention is obtained, and the fiber samples obtained above are obtained. The Oxygen Permeability Index (L.O.I) flame resistance test was carried out according to the American ASTM D2863-1995 test standard.

The Limit of Oxygen Index (L.O.I) value is the value of the minimum oxygen concentration required for continuous combustion of a fiber or fabric sample placed in a combustion cylinder. The calculation formula is as follows:

The fiber or fabric having a higher oxygen limiting index requires a high concentration of oxygen during combustion, in other words, is less prone to combustion.

The various test results obtained above are shown in sample numbers F1 to F24 in [Table 5] and in sample numbers T1 to T24 in [Table 6].

Example 5 (flame resistance test after 50 washings):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with an oxidized methyl marlin (NMMO) solvent to form a slurry and incorporated with a 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer. Then use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, you can dissolve the cellulose into a dope, and then measure the mucus The pump is sent to a spinning machine for spinning, extruded through a spinning port by extrusion, and regenerated by a dry-jet wet spinning method (Dry-jet Wet Spinning), and then washed and dried to form natural cellulose. a fiber, which is padded with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and has a rolling rate of 65% to 70%, and the N-hydroxyl group The concentration of the base-3-(dimethoxyphosphonium)propionamide flame retardant is from 0g/L to 450g/L, the baking temperature is from 130°C to 180°C, the baking time is from 120 seconds to 240 seconds, and then the fiber is neutralized. After washing with soap, washing with water, drying, washing with alkali, washing with water, drying, oiling and coiling, the natural cellulose filament having the flame resistance function of the present invention is obtained, and the fiber samples obtained above are obtained. First, according to AATCC 135-2004 Option 1 (2) v1 A (i) 4Lb Load water washing method, after washing 50 times, and then according to the American ASTM D6413-1999 test standard for various flame test, the results of various tests According to the sample numbers F1 to F24 in [Table 7] and the sample numbers T1 to T24 in [Table 8].

Example 6 (Oxygen limit index flame resistance test after 50 washes):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with an oxidized methyl marlin (NMMO) solvent to form a slurry and incorporated with a 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer. Then use a vacuum film evaporator to evaporate excess water, heat at 80 ° C ~ 120 ° C, remove water to 5% ~ 13% within 5 minutes, you can dissolve the cellulose into a dope, and then measure the mucus The pump is sent to a spinning machine for spinning, extruded through a spinning port by extrusion, and regenerated by a dry-jet wet spinning method (Dry-jet Wet Spinning), and then washed and dried to form natural cellulose. a fiber, which is padded with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and has a rolling rate of 65% to 70%, and the N-hydroxyl group The concentration of the base-3-(dimethoxyphosphonium)propionamide flame retardant is from 0g/L to 450g/L, the baking temperature is from 130°C to 180°C, the baking time is from 120 seconds to 240 seconds, and then the fiber is neutralized. After washing with soap, washing with water, drying, washing with alkali, washing with water, drying, oiling and coiling, the natural cellulose filament having the flame resistance function of the present invention is obtained, and the fiber samples obtained above are obtained. First, according to AATCC 135-2004 Option 1 (2) v1 A (i) 4Lb Load water washing method, after 50 times of water washing, and then according to the American ASTM D2863-1995 test standard for oxygen limited index (LOI) flame resistance test, which results The test results are shown in sample numbers F1 to F24 in [Table 9] and in sample numbers T1 to T24 in [Table 10].

The results of various flame resistance tests in the above [Table 3], [Table 4], [Table 5] and [Table 6] show that the flame resistant natural cellulose fiber of the present invention, when N-hydroxymethyl-3-( The content of the methoxyphosphonium-based acetaminophen flame retardant can reach the oxygen limit index (LOI) of 25 or more, and meet the test standards of ASTM D6413-1999 and ASTM D2863-1995. Then the content of N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide flame retardant should be above 350g/L, that is, the limit of oxygen index (LOI) should reach 32 or more; but when N-hydroxyl When the content of methyl-3-(dimethoxyphosphonium)propionamide flame retardant exceeds 450 g/L, the oxygen index (LOI) value may be as high as 38 or more, but the physical properties of the fiber have a downward trend. As shown in [Table 2], the N-hydroxymethyl-3-(dimethoxyphosphonyl)propanamide is flame resistant under the condition that the physical properties of the fiber cannot be lowered and the cost of the flame retardant is not excessively high. The content of the agent should not exceed 450g/L. Therefore, the examples of [Table 3], [Table 4], [Table 5] and [Table 6] can prove that the present invention can achieve the effect of flame resistance.

The results of the flame resistance test after 50 times of washing in [Table 7], [Table 8], [Table 9] and [Table 10] show that the flame-resistant function of the fiber after 50 times of washing treatment of the present invention It still maintains the original unwashed effect, and can also meet the test standards of ASTM D6413-1999 and ASTM D2863-1995, which proves that the long-lasting flame-resistant cellulose fiber of the present invention has far more flame resistance than the general market. A flame-resistant fiber coated with a flame retardant or a flame retardant is commercially available.

In summary, the flame-resistant natural cellulose fiber produced according to the present invention has a cross-linking reaction with the natural cellulose fiber due to the N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant in the process. Therefore, the fabric can still meet the requirements of flame resistance after 50 times of water washing, and the flame resistance effect meets the test standard requirements of ASTM D6413-1999 and ASTM D2863-1995, and the invention can also be based on N-hydroxymethyl- The addition ratio of 3-(dimethoxyphosphonium)propionamide flame retardant is made into flameproof natural cellulose fiber of different specifications, and the fiber strength reduction rate is ≦10%, and the flame resistant natural cellulose fiber or its fabric is used. After being discarded, it can be naturally decomposed, and it can become a material that meets environmental protection requirements. It is highly industrially applicable and meets the requirements of invention patents.

First Figure: A manufacturing flow diagram of the present invention.

The second figure is a chemical structure diagram of N-methylmorpholine N-oxide (NMMO) used in the present invention.

Fig. 3 is a chemical structural diagram of a flame retardant of N-hydroxymethyl-3-(dimethoxyphosphonyl)propanamide used in the present invention.

The representative figure of this case does not have the symbol of the component, so there is no simple description of the symbol of the component in the abstract of this case.

Claims (9)

A method for preparing a natural cellulose fiber having a flame-resistant function comprises the steps of: (a) mixing a wood pulp with a solvent of N-methylmorpholine N-oxide (NMMO) to form a slurry. In addition, 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer is added, and the above-mentioned wood pulp, oxidized methyl marlin (NMMO) solvent and phenyl ketone are used. After the oxazodine and the like are placed together, the pulp is pulverized at a low temperature of 60 ° C to 80 ° C; wherein the wood pulp is a long fiber or a short fiber of cellulose having an α-cellulose content of 85% or more. And its cellulose degree of polymerization (DP) is 500 ~ 1200; (b) using a vacuum film evaporator (Thin Film Evaporator, TFE) to evaporate excess water, heated at 80 ° C ~ 120 ° C, The water is removed to 5% to 13% in 5 minutes, and the cellulose is dissolved into a spinning dope; (c). Spinning by Dry-Jet Wet Spinning, After the spinning mucus is squeezed out from the spinning nozzle, it enters the coagulation bath to solidify and regenerate the yarn; (d). The solidified regenerated spinning is washed and dried. And the natural cellulose fiber is prepared, wherein the drying temperature is 100 ° C ~ 130 ° C, the time is 3 ~ 5 seconds; (e). The natural cellulose fiber and N-hydroxymethyl-3- (dimethoxyphos The mercapto) acrylamide flame retardant is padded at a bathing rate of 65% to 70%, and the concentration of the N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide flame retardant is 250 g/ L～500g/L; (f). The natural cellulose fiber after padding is sequentially dried, baked, neutralized, soaped, washed and dried; wherein the drying temperature of the drying is 105°C. The drying time is 10 seconds, and the baking is performed twice. The baking temperature of the first baking is 130 ° C to 155 ° C, the baking time is 60 seconds to 120 seconds, and the baking temperature of the second baking is 165 ° C to 180 °C, baking time is 60 seconds to 120 seconds, the concentration of the alkali solution used for the neutralization is 50g / L, the neutralization temperature is 20 ° C ~ 30 ° C, the concentration of the alkali solution used for the soaping is 2g / L, the soaping The soap powder used is 3g/L, the soaping temperature is 20 ° C ~ 30 ° C, the soaping time is 10 seconds; and (g). Finally, after alkali washing, washing and drying procedures, and oiling, it can be made. Natural fiber with long-lasting flame resistance Plain fiber, and can be wound into a long fiber according to the desired form of the product, or cut into short fibers according to the length specification. The method for producing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the concentration of the oxidized methyl marlin (NMMO) in the step (a) is 50% to 75%. The method for producing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the natural cellulose is wound at a speed of 200 to 600 meters per minute in the step (g). The method for producing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the fiber strength of the natural cellulose fiber obtained by spinning in the step (g) is from 3.0 g/d to 5.0 g. /d. The method for producing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the fiber obtained by spinning in the step (g) has a fiber elongation of 4.0% to 8.0%. The method for producing a natural cellulose fiber having a flame-resistant function according to the first aspect of the patent application, wherein the fiber of the natural cellulose fiber obtained by spinning in the step (g) has a Young's modulus of 50 g/d to 150 g. /d. The method for preparing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the alkali liquid used for soaping in the step (f) is sodium hydroxide (NaOH) or sodium carbonate (Na). ₂ CO ₃ ). The method for preparing a natural cellulose fiber having a flame-resistant function according to the first aspect of the invention, wherein the alkali solution used in the alkali washing in the step (g) is sodium hydroxide (NaOH) or sodium carbonate (Na) ₂ CO ₃ ). The method for preparing a natural cellulose fiber having a flame-resistant function as described in the first paragraph of the patent application, the step of recovering the solvent in the process comprises: A. Decolorization: the decolorization is carried out by means of activated carbon suspension, and the decolorization liquid is added. 0.05% to 0.10% of activated carbon powder with good adsorption and suspension properties, alternately treated by blast-mixing adsorption and static suspension adsorption, and the treatment time ratio of the two is 1:3 to 1:6, and the treatment time is 8 B. Filtration: The system uses two-stage filtration. The first stage coarse filtration uses a general filter-type filter, and the filter aid is pre-coated on the surface of the filter element, and 0.03% is added to the unfiltered filtrate. 0.05%, the unfiltrated filtrate contains a small amount of bulking filter aid, the composition ratio of the filter aid is diatomaceous earth: cellulose = 4:1, after the coarse filtration is completed, the residue residue is centrifuged, dehydrated, recovered, and dehydrated. The post-filtration filter aid is reused once, while the second-stage fine filtration system uses a precision filter UF; C. Concentration: When the fiber yield is low: the three-effect concentration method is used, and the water removal per ton is About 0.5 tons of steam is needed, and its steam consumption is high, but electricity The power consumption is small; when the fiber production is slightly larger: the MVR concentration method is adopted, and the water removal requires about 0.003 to 0.03 tons of steam per ton, and the steam consumption is low, but the power consumption is slightly larger, and the two kinds of concentration methods are generated. The concentrate and the condensed water are all recovered; wherein the concentrate is used for the solvent of the process; the condensed water can be used for washing the raw silk; and D. refining: using 80 ° C low temperature oxidation and neutralization reduction, with 35% H ₂ O ₂ is an oxidant, 85% N ₂ H ₄ ‧H ₂ O is a neutralizing reducing agent, and then the result of redox determination by potentiometric titration, the NMMO content can be reduced to below 10 ppm, and the NMMO purity and loss can be improved. .