TWI596247B - Preparation of natural cellulose meltblown nonwovens with flame resistance - Google Patents

Description

Method for producing natural cellulose melt-blown non-woven fabric with flame resistance

The invention relates to a "manufacturing method of a natural cellulose melt-blown non-woven fabric with a flame-resistant function", which belongs to the technical field of manufacturing a natural fiber non-woven fabric by a green environmental protection process, and is based on N-hydroxymethyl-3-(dimethoxyphosphonium). Baseline) Propyleneamine flame retardant and natural cellulose non-woven fabric are padded, dried, baked, neutralized, soaped, washed and dried to cause cross-linking reaction between active N-methylol and natural cellulose non-woven fabric. After washing with alkali, washing with water, drying, oiling and coiling, a natural cellulose non-woven fabric having a long-lasting flame resistance function can be obtained.

At present, in the non-woven fabric manufacturing technology, the polymer laid-out method (polymer laid, spunlaid) has the advantages of simple process and high economic efficiency, and the step of extruding and extending the molten polymer to form continuous long fibers. The long fibers are stacked into a net to form a non-woven fabric; since the long fibers impart good physical properties to the non-woven fabric, such non-woven fabrics are widely used in the fields of sanitary articles, wiping materials, medical protection and filter materials, and become the most growing non-woven fabric manufacturing technology. Fast field.

The above-mentioned four kinds of raw materials used in the above-mentioned direct extrusion method are polypropylene (PP), polyester (PET), polyethylene (PE) and nylon (Nylon), which together account for 96% of the total use. When these non-woven fabrics become waste after being used, they cannot be decomposed by the natural environment, and according to the statistics and predictions of the American Nonwoven Industrial Association (INDA), the production rate of non-woven fabrics produced by the polymer extrusion forming method is It will grow from 33.5% (second place) in 1994 to 43.7% (first place) in 2009 and reach 2.7 million tons per year. This amazing growth will also have a greater impact on the environment. burden.

In addition, as countries have successively formulated textile flammability technical regulations, if products do not meet the requirements of these regulations, they will be prevented from entering the country's market. Therefore, the demand for flame-retardant and non-woven fabrics is increasing. In addition to non-woven fabrics for wiping, industrial non-woven fabrics, home furnishings, curtains, etc. used in many industrial and home decoration must have considerable fire resistance to avoid accidents. However, the above polypropylene (PP), polyester ( Non-woven fabrics such as PET), polyethylene (PE) and nylon (Nylon) are non-degradable fibers, and the waste after use is of course not naturally degradable, so it will cause more damage to the natural environment. A big harmful burden.

In view of this, how to make a natural cellulose fiber (ie, soluble fiber) that does not harm the natural environment and produce a special cross-linking reaction under the set process conditions, thereby producing a natural cellulose non-woven fabric having a long-lasting flame-resistant function. It seems urgent and urgent.

The main object of the present invention is to provide a "method of producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function" by mixing a wood pulp with a solvent of N-methylmorpholine N-oxide (NMMO) to form a slurry ( Slurry), removing the water by a Thin Film Evaporator (TFE) to form a spinning dope, and extruding the mucus from the spinning mouth to form a cellulose tow, and ejecting a water mist. After the cellulose tow is coagulated and regenerated, it is washed with water, needled and dried to form a natural cellulose non-woven fabric, which is then resistant to burning with N-methylol-3-(dimethoxyphosphonium)propionamide. The agent is padded, and then subjected to drying, baking, neutralization, soaping, washing and drying, and finally, after alkali washing, water washing, drying and coiling, a long-lasting flame-resistant function can be obtained. Natural cellulose non-woven fabric; the natural cellulose non-woven fabric with flame-resistant function can produce special cross-linking reaction with N-hydroxymethyl-3-(dimethoxyphosphonium)-propionamide flame retardant in the process, 20 times After the water washing treatment, the non-woven fabric's flame-resistant function still maintains the original unwashed The effect, in full compliance with the American Standard Test ASTM D6413-1999 requirement and ASTM D2863-1995, and which can be discarded after use biodegradable, harmless and environmentally friendly materials natural environment.

Another object of the present invention is to provide a "manufacturing method of a natural cellulose melt-blown nonwoven fabric having a flame-resistant function", wherein the solvent recovery and regeneration method in the process is a streamlined and effective apparatus and is subjected to decolorization, filtration, concentration, refining, etc. The four main procedures, the water washing liquid is recovered into a oxidized methyl marlin (NMMO) solvent of the same quality as the fresh solvent, the loss rate is below 0.5%, and the total recovery rate is over 99.5%, except for the environment. In addition to causing pollution, 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:

Please refer to the first to fourth figures, the "manufacturing method of natural cellulose melt-blown non-woven fabric with flame-resistant function" of the present invention, the steps of which include:

(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 low temperature of 60 ° C ~ 80 ° C - 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 mucilage ( Dope);

(c) by melt-blowing the mucus D from the spun to form a cellulose tow; as shown in the third figure, the mucus D is driven into the spinning die 2 by the gear pump 1 and then enters In the spinning nozzle 3 of the spinning die 2, after the hot air H is continuously poured into the spinning die 2, and the airflow discharged from around the spinning nozzle 3 acts, the slime D is forced to be melted from the spinning nozzle 3. Extruding the outer formed cellulose tow;

(d). Spraying water mist to solidify and regenerate the cellulose tow, and then washing with water, needle rolling and drying to obtain a natural cellulose non-woven fabric, wherein the drying temperature is 100 ° C to 130 ° C, and the time is 3 to 5 second;

(e). The natural cellulose non-woven fabric is padded with a N-methylol-3-(dimethoxyphosphonium)propionamide 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 450 g/L, and the chemical structure diagram thereof is as shown in the fourth figure;

(f). The natural cellulose non-woven fabric after padding is sequentially subjected to drying, baking, neutralization, soaping, water washing and drying; wherein the drying temperature of the drying 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, water washing, drying and coiling, a natural cellulose non-woven fabric having a long-lasting flame resistance function can be obtained; wherein the alkali washing liquid used is NaOH or Na ₂ CO ₃ The winding speed is 2 to 200 meters per minute.

Wherein, in step (b), the cellulose content of the mucilage is 6 wt% to 15 wt%, the viscosity of the mucus is 300 to 3000 (poise), the light transmittance of the mucus is 1.470 to 1.495, and the melt index of the mucus is 200 to 1000. .

Further, in the step (g), the natural cellulose melt-blown nonwoven fabric has a basis weight of the cellulose non-woven fabric of 10 g/m ² to 300 g/m ² , a fiber fineness of 1 to 15 μm, and a mechanical direction (MD) stretching of the non-woven fabric. The strength is 15 kgf or more, and the tensile strength in the vertical direction (CD) is 8 kgf or more.

In the step (a), the phenyloxazole stabilizer is incorporated into the addition, for example, by incorporating a phenyl oxazole of 500 to 2500 PPM in a solvent of oxidized methylmaline (NMMO) (1,3). -phenylene bis-2 oxazoline), and then blended with wood pulp to form a slurry, as shown in the following list (A):

In addition, the phenyloxazole stabilizer used in the present invention is produced compared to the conventional sodium hexametaphosphate (SHMP) stabilizer and n-proply gallate (PG) stabilizer. Less coloring, the coloring index is 470nm, 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 process can be simplified and the solvent recovery rate can be improved; and the unit price is also better than the conventional one. The additives are much cheaper and help 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 0.05wt%~0.10wt% of activated carbon powder with good adsorption and suspension property to the decolorization liquid, alternating treatment with blast mixing and reconstitution 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, 0.03wt%~0.05wt% is also added to the unfiltered filtrate, so that the filtrate does not contain a small amount of bulking filter aid, the filtration speed is greatly improved and can be maintained without shrinking. The filter aid is composed of algae Soil: 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 filter residue after dehydration still has the filter effect and can be reused 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 prove the characteristics and implementation effects of the present invention, various test examples are completed and explained as follows:

Example 1 (sample numbers D1 to D6 and F1 to F6 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 And the anti-polymerization degree decay agent, then use the vacuum film evaporator to evaporate the excess water, heat at 80 ° C ~ 120 ° C, remove the water to 5% ~ 13% within 5 minutes, then dissolve the cellulose into mucus (dope ), the composition of the mucus is as shown in the sample No. D1 to D6 in [Table 1], and the mucus is melted by a meltbrown through a spun to form a cellulose tow, and the water mist is sprayed to solidify the cellulose tow. After regeneration, it is made into a natural cellulose non-woven fabric by water washing, water needle rolling and drying, and the natural cellulose non-woven fabric is immersed with N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide 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 non-woven fabric is neutralized, soaped, washed, dried, and then alkali-washed, washed, dried, oiled and coiled to produce flame-resistant work. The natural cellulose non-woven fabric can be obtained, and the non-woven fabric samples obtained above are shown in the sample numbers F1 to F6 in [Table 2].

Example 2 (sample numbers D7 to D12 and F7 to F12 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 And the anti-polymerization degree decay agent, then use the vacuum film evaporator to evaporate the excess water, heat at 80 ° C ~ 120 ° C, remove the water to 5% ~ 13% within 5 minutes, then dissolve the cellulose into mucus (dope ), the composition of the mucus is as shown in the sample No. D7 to D12 in [Table 1], and the mucus is extruded by a melt blow method to form a cellulose tow, and the water mist is sprayed to solidify the cellulose tow. After regeneration, it is made into a natural cellulose non-woven fabric by water washing, water needle rolling and drying, and the natural cellulose non-woven fabric is immersed with N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide 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 non-woven fabric is neutralized, soaped, washed, dried, then alkali washed, washed, dried, oiled and coiled to make it flame resistant. The nonwoven can be natural cellulose, the fiber sample obtained above was added [Table II] Sample No. F7 ~ F12 in FIG.

Example 3 (flame resistance test):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with a oxidized methyl marlin (NMMO) solvent to form a slurry, and 1,3-phenylene-bis 2-oxazoline is added in different proportions. BOX) stabilizer and anti-polymerization decay agent, then use vacuum film evaporator to evaporate excess water, heat at 80 °C ~ 120 °C, remove water to 5% ~ 13% within 5 minutes, then dissolve cellulose into Muc (dope), the mucus is melted by meltblowing through the spinning to form a cellulose tow, sprayed with water mist to solidify and regenerate the cellulose tow, and then washed by water, water needle rolling and drying. Forming a natural cellulose non-woven fabric, and impregnating the natural cellulose non-woven fabric with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and the rolling rate thereof is 65% to 70%. The concentration of N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide is 0g/L～450g/L, the baking temperature is 180°C, the baking time is 240 seconds, and then the non-woven fabric is neutralized. After soaping, washing with water, drying, then alkali washing, washing, drying, oiling and coiling to produce a natural cellulose non-woven fabric with flame resistance, the above Each fiber sample was subjected to various flame resistance tests according to the American ASTM D6413-1999 test standard.

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 F12 in [Table 3] and in sample numbers T1 to T12 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 a oxidized methyl marlin (NMMO) solvent to form a slurry, and 1,3-phenylene-bis 2-oxazoline is added in different proportions. BOX) stabilizer and anti-polymerization decay agent, then use vacuum film evaporator to evaporate excess water, heat at 80 °C ~ 120 °C, remove water to 5% ~ 13% within 5 minutes, then dissolve cellulose into Muc (dope), the mucus is melted by meltblowing through the spinning to form a cellulose tow, sprayed with water mist to solidify and regenerate the cellulose tow, and then washed by water, water needle rolling and drying. Forming a natural cellulose non-woven fabric, and impregnating the natural cellulose non-woven fabric with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and the rolling rate thereof is 65% to 70%. The concentration of N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide is 0g/L～450g/L, the baking temperature is 180°C, the baking time is 240 seconds, and then the non-woven fabric is neutralized. After soaping, washing with water, drying, then alkali washing, washing, drying, oiling and coiling to produce a natural cellulose non-woven fabric with flame resistance, the above Each fiber sample was subjected to an Oxygen Permeability Index (L.O.I) flame resistance test 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 F12 in [Table 5] and in sample numbers T1 to T12 in [Table 6].

Example 5 (flame resistance test after 20 washings):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with a oxidized methyl marlin (NMMO) solvent to form a slurry, and 1,3-phenylene-bis 2-oxazoline is added in different proportions. BOX) stabilizer and anti-polymerization decay agent, then use vacuum film evaporator to evaporate excess water, heat at 80 °C ~ 120 °C, remove water to 5% ~ 13% within 5 minutes, then dissolve cellulose into Muc (dope), the mucus is melted by meltblowing through the spinning to form a cellulose tow, sprayed with water mist to solidify and regenerate the cellulose tow, and then washed by water, water needle rolling and drying. Forming a natural cellulose non-woven fabric, and impregnating the natural cellulose non-woven fabric with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and the rolling rate thereof is 65% to 70%. The concentration of N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide is 0g/L～450g/L, the baking temperature is 180°C, the baking time is 240 seconds, and then the non-woven fabric is neutralized. After soaping, washing with water, drying, then alkali washing, washing, drying, oiling and coiling to produce a natural cellulose non-woven fabric with flame resistance, the above Each non-woven sample was first washed according to the water washing method of AATCC135-2004 Option 1(2)v1 A(i) 4Lb Load for 20 times, and then subjected to various flame resistance tests according to the American ASTM D6413-1999 test standard. The test results are shown in sample numbers F1 to F12 in [Table 7] and in sample numbers T1 to T12 in [Table 8].

Example 6 (Oxygen limit index flame resistance test after 20 washes):

The wood pulp cellulose having a degree of polymerization of 650 and 1050 is separately mixed with a oxidized methyl marlin (NMMO) solvent to form a slurry, and 1,3-phenylene-bis 2-oxazoline is added in different proportions. BOX) stabilizer and anti-polymerization decay agent, then use vacuum film evaporator to evaporate excess water, heat at 80 °C ~ 120 °C, remove water to 5% ~ 13% within 5 minutes, then dissolve cellulose into Muc (dope), the mucus is melted by meltblowing through the spinning to form a cellulose tow, sprayed with water mist to solidify and regenerate the cellulose tow, and then washed by water, water needle rolling and drying. Forming a natural cellulose non-woven fabric, and impregnating the natural cellulose non-woven fabric with a N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant, and the rolling rate thereof is 65% to 70%. The concentration of N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide is 0g/L～450g/L, the baking temperature is 180°C, the baking time is 240 seconds, and then the non-woven fabric is neutralized. After soaping, washing with water, drying, then alkali washing, washing, drying, oiling and coiling to produce a natural cellulose non-woven fabric with flame resistance, the above Each non-woven sample was first subjected to water washing for 20 times according to AATCC 135-2004 Option 1(2) v1 A(i) 4Lb Load water washing method, and then subjected to the Oxygen Permeability Index (LOI) flame resistance test according to the American ASTM D2863-1995 test standard. The test results obtained are shown in sample numbers F1 to F12 in [Table 9] and sample numbers T1 to T12 in [Table 10], respectively.

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 non-woven fabric 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)propanamide flame retardant should be above 350g/L, that is, the value of oxygen limit index (LOI) should reach 32 or more; The examples of [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 washing 20 times in [Table 7], [Table 8], [Table 9] and [Table 10] show that the flame-retardant function of the non-woven fabric after 20 times of water 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 can prove the long-lasting flame-resistant cellulose non-woven fabric of the present invention, and its flame resistance is far superior to that of the general market. A flammable non-woven fabric that is coated with a flame retardant or a flame retardant is commercially available.

In summary, the flame resistant natural cellulose non-woven fabric manufactured according to the present invention has a cross-linking reaction with the natural cellulose non-woven fabric due to the N-methylol-3-(dimethoxyphosphonium)propionamide flame retardant in the process. Therefore, after 20 times of water washing, the requirements of flame resistance can still be met, 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-3. - (Dimethoxyphosphonium) propyleneamine flame retardant addition ratio, made of different specifications of flame-resistant natural cellulose non-woven fabric, its fiber strength reduction rate ≦ 10%, and the flame-resistant natural cellulose non-woven fabric can be discarded after use It is naturally decomposed and can be a material that meets environmental protection requirements. It is highly industrially applicable and meets the requirements of invention patents.

1. . . Gear pump

2. . . Mold

3. . . Spin nozzle

D. . . Mucus

H. . . hot air

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 schematic view showing the operation of the meltblown cellulose tow in the present invention.

Figure 4 is a chemical structure diagram of the N-hydroxymethyl-3-(dimethoxyphosphonyl)propanamide flame retardant used in the present invention.

The representative figure of this case does not have the symbol of the component.

Claims (11)

A method for preparing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function, comprising the steps of: (a) mixing a wood pulp with a solvent of N-methylmorpholine N-oxide (NMMO) to form a slurry (slurry) ), in addition to 1,3-phenylene-bis 2-oxazoline (BOX) stabilizer, and using a horizontal pulper, the aforementioned wood pulp, oxidized methyl marlin (NMMO) solvent and benzene After the oxazole stabilizer is put together, the pulp is further pulverized at a low temperature of 60 ° C to 80 ° C; wherein the wood pulp is a long fiber or short fiber containing 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, Excluding water to 5% to 13% in 5 minutes, dissolving cellulose into dope; (c) extruding mucus from the spun by meltblowing to form cellulose tow; (d The water mist is sprayed to solidify and regenerate the cellulose tow, and then washed with water, needled and dried to form a natural cellulose non-woven fabric, wherein The drying temperature is 100 ° C ~ 130 ° C, the time is 3 ~ 5 seconds; (e). The natural cellulose non-woven fabric and N-methylol-3- (dimethoxyphosphonium) propiamine flame retardant Rolling, the rolling rate is 65% to 70%, the concentration of the N-hydroxymethyl-3-(dimethoxyphosphonium)propionamide flame retardant is 250g / L ~ 450g / L; (f). The natural cellulose non-woven fabric after padding is sequentially subjected to drying, baking, neutralization, soaping, water washing and drying; wherein the drying temperature of the drying is 105 ° C, the drying time is 10 seconds, baking points Two times, the first baking temperature is 130 ° C ~ 155 ° C, baking time is 60 seconds ~ 120 seconds, then the second baking baking temperature is 165 ° C ~ 180 ° C, baking time is 60 seconds ~ 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, soap. The washing temperature is 20 ° C ~ 30 ° C, the soaping time is 10 seconds; and (g). Finally, after alkali washing, washing, drying and coiling, a natural cellulose non-woven fabric with long-lasting flame resistance can be obtained. Wherein, in step (a), oxidized methyl marlin (NMM) The concentration of O) is 50%~75%; the steps of solvent recovery in the process include: A. Decolorization: decolorization by activated carbon suspension, and 0.05 wt% to 0.10 wt% adsorption and suspension of non-decolorization solution A good activated carbon powder is 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 more than 8 hours; B. Filtration: The second-stage filtration is adopted. 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 wt% to 0.05 wt% is added to the unfiltered filtrate, so that the unfiltered filtrate contains a small amount. The 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 the dewatered filter residue filter aid is re-filtered. It is recycled once, while the second stage of fine filtration uses the precision filter UF; C. Concentration: When the fiber yield is low: it adopts three-effect concentration method, and its water removal requires about 0.5 tons of steam per ton. Steam consumption is high, but power consumption is small; when fiber production is slightly larger: MVR concentrate is used In the formula, the water removal requires about 0.003~0.03 tons of steam per ton, and the steam consumption is low, but the power consumption is slightly larger. The concentrated liquid and the condensed water produced by the two kinds of concentration methods are all recovered; wherein the concentrated liquid is available for the process For solvent use; condensate for water washing; and D. refining: low temperature oxidation and neutralization reduction at 80 ° C, 35% H ₂ O ₂ as oxidant, 85% N ₂ H ₄ . H ₂ O is a neutralizing reducing agent, and the result of redox determination by potentiometric titration can reduce the NMM content to below 10 ppm, and can improve NMMO purity and reduce loss. The method for producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function as described in the first aspect of the patent application, wherein the winding speed in the step (g) is 2 to 200 meters per minute. The method for producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function according to the first aspect of the invention, wherein the cellulose content of the mucus in the step (b) is 6 wt% to 15 wt%. For example, the method for preparing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function as described in the first paragraph of the patent application, wherein the mucus in the step (b) The viscosity is 300~3000 (poise). For example, the method for preparing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function according to the first aspect of the patent application, wherein the light transmittance of the mucus in the step (b) is 1.470 to 1.495. The method for producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function as described in the first aspect of the patent application, wherein the melt index of the mucus in the step (b) is 200 to 1000. For example, the method for preparing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function as described in the first aspect of the patent application, wherein the base cellulose of the cellulose non-woven fabric obtained by the step (g) has a basis weight of 10g/m ² ~ 300g/m ² . The method for producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function, as described in claim 1, wherein the natural cellulose melt-blown nonwoven fabric obtained in the step (g) has a fiber fineness of 1 to 15 μm. The method for producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function as described in the first paragraph of the patent application, wherein the natural cellulose melt-blown nonwoven fabric obtained in the step (g), the mechanical direction of the non-woven fabric (MD) The tensile strength is 15 kgf or more, and the tensile strength in the vertical direction (CD) is 8 kgf or more. The method for preparing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function according to the first aspect of the patent application, 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 producing a natural cellulose melt-blown nonwoven fabric having a flame-resistant function according to the first aspect of the patent application, wherein the alkali solution used in the alkali washing in the step (g) is sodium hydroxide (NaOH) or sodium carbonate. (Na ₂ CO ₃ ).