KR800001196B1 - Method for producing a flame retardant acrylic fiber improvement in fiber properties - Google Patents

Abstract

Fire-resistant acrylic fibers with good transparency, luster, and dyed brightness, were prepd. by wet spinning a halogen-contg. spinning soln. contg. Sb2O3 and regulating the atm. of water in he hot-stretched hydrogel fiber to 50-130wt.% (based on fiber-forming polymer) by controlling compn. (content of hydrophilic group in copolymer) polymer concn. in the spinning soln., or spinning condition. A spinning soln. in 50% aq. NaSCN contained 10% 82.7:8:0:.3:9 acrylonitrile - Me acrylate - sodium methallylsulfonate-vinylidene chloride copolymer and 5.3% 15μm Sb2O3.

Description

Manufacturing method of flame retardant acrylic fiber with improved fiber performance

FIG. 1 illustrates the relationship between the internal moisture content of gel-like acrylic fibers and the degree of deterioration of color development (ΔK / S ratio) due to the drying of a dye.

2 shows the relationship between the degree of deterioration of color development and transparency of the flame retardant acrylic fiber described above.

The present invention relates to a method for producing a flame-retardant acrylic fiber with improved fiber performance, in the production of flame-retardant acrylic fiber by wet spinning a halogen-containing acrylic spinning stock solution by dispersing antimony oxide particles, under the heat stretching after wet spinning By adjusting the internal moisture content of the fibers in the obtained hydrogel state to a specific range by any means, it is possible to industrially produce acrylic fibers having a high flame retardancy which significantly improved the fiber performance of transparency, gloss and color clarity of dyeing. It relates to a method that can be produced by.

Acrylic fibers made of conventional acrylonitrile-based polymers or copolymers have a wide range of applications in the field of medical interiors, and are inherently flame retardant, and may be used for certain specific applications such as carpets, It is undesirable to use for upholstery such as curtains and dressings for infants.

하는 방법 혹은 난연제로서 후 가공하는 방법 등이 채택되고 있으나, 이들 재래의 난연화 방법에서는 일단 아크릴계 섬유소재에 난연성을 부여한다고는 하나 보다 고도한 난연성을 부여하는 것은 곤란하므로, 할로겐과 같이 산화 안티몬 등의 난연성 상승제를 아크릴계 섬유에 도입시켜서, 보다 고도의 난연성을 부여하는 방법이 제안되었었다.In order to overcome the drawbacks associated with these acrylic fibers, a method of copolymerizing flame retardant monomers such as acrylonitrile and halogen-containing unsaturated monomers, a method of mixing and spinning acrylonitrile-based polymers and flame retardant polymers, halogen-containing Flame retardant is injected into spinning solution

Or post-processing methods have been adopted as flame retardants. However, in these conventional flame retardant methods, it is difficult to impart more flame retardancy to acrylic fiber materials, but it is difficult to impart higher flame retardancy. A method of imparting higher flame retardancy by introducing a flame retardant synergist to acrylic fibers has been proposed.

If adopting the method of introducing antimony oxide into the acrylic fiber like halogen, it is not possible to give the final fiber with the fiber performance such as transparency, gloss, and color development which are practically satisfactory for the final fiber. It has become difficult to produce flame retardant acrylic fiber products having a commodity value.

Here, the inventors have continued serious research to improve the defects accompanying these cultivation techniques, and as a result, the fiber-forming polymer component composition in producing flame-retardant acrylic fibers from halogen-containing acrylic spinning stock obtained by dispersing antimony oxide particles, or By adjusting the spinning conditions, the internal moisture content of the gel acrylic fiber obtained by thermal stretching after wet spinning is maintained in a specific range, thereby remarkably improving the fiber performance such as transparency of the final fiber, gloss and color clarity of the dye, and color development. The present invention has been found to be improved.

An important object of the present invention is to provide a method for producing a flame retardant acrylic fiber with remarkably improved fiber performance.

Another main object of the present invention is to industrially advantageously produce acrylic fibers having high flame retardancy and excellent transparency and glossiness and not causing deterioration of color development due to drying.

Other objects of the present invention will become apparent from the following detailed description of the invention. Thus, an object of the present invention is a halogen obtained by dispersing antimony oxide having a particle size of 100 μm or less in a solvent solution of an acrylonitrile copolymer copolymerized with a halogen containing unsaturated monomer or an acrylonitrile polymer composition containing a halogen containing flame retardant component. In producing a flame-retardant acrylic fiber according to a conventional wet spinning method with the containing acrylic spinning stock solution, it is achieved by adjusting the internal moisture content of the gel-like fibers obtained by heat stretching after wet spinning to 50-130% by weight relative to the fiber-forming polymer.

The acrylic fiber obtained according to the method of the present invention has a high flame retardancy due to the synergistic effect of halogen and antimony oxide, and since there is no cavity in the fiber, it is excellent in transparency and gloss and at the same time, the headlamp after dyeing Deterioration of color vividness, color deterioration is not caused entirely, the product value is extremely high.

Particularly important in producing acrylic fibers having such unusual fiber performance is the amount of water present in the acrylic fibers in the hydrogel state obtained by thermal stretching after wet spinning, that is, the internal moisture content is 50 to 130% by weight relative to the fiber-forming polymer. In tune. In order to clarify this fact, the following description will be given with reference to FIGS. 1 and 2.

First, Figure 1 illustrates the relationship between the internal moisture content of the gel-like acrylic fiber and the degree of deterioration of color development (ΔK / S ratio) (described later) in accordance with the drying of the dyeing of the final fiber, but in the gel It is understood that the ΔK / S ratio gradually decreases as the amount of water present in the acrylic fiber increases, and the color change due to the inferiority of the final fiber is remarkably improved. In the present invention, if the ΔK / S ratio is less than 10% (the internal moisture content of the gel-like fiber is 50% by weight or more), the dyed material of the final fiber undergoes a heat history such as drying, thereby degrading color development. It was confirmed that unfavorable conditions such as deterioration of color clarity did not occur. FIG. 2 shows the relationship between the ΔK / S ratio and the transparency of the final fiber. However, in FIG. 2, the degree of deterioration of color development due to the drying of the dyestuff is decreased (in the direction of increasing the internal moisture content of the gel-like fiber). Accordingly, it is clearly understood that the transparency can be increased, and the transparency and gloss of the outermost fibers can be significantly improved. On the other hand, in this invention, when such transparency is 20% or more (when the internal moisture content of a gel-like fiber is 50 weight% or more), it was confirmed that transparency and glossiness of a final fiber can be improved. In addition, when the internal moisture content of the gel acrylic fiber exceeds 130% by weight with respect to the fiber-forming polymer, in the manufacturing process of the flame-retardant acrylic fiber, the fibers are interlaced with each other or a defective yarn (pharmacist) occurs. It is not preferable because it causes problems. On the other hand, the deterioration degree (ΔK / S ratio) of the internal moisture content of the gel acrylic fiber, the transparency of the acrylic fiber, and the color development of the dyed product is calculated by the following measurement.

(1) internal moisture content

After putting the gel acrylic fiber into the centrifugal dehydrator and dehydrating the gel fiber at 3000 r.pm for 2 minutes, the moisture content (%) remaining in the gel acrylic fiber was measured by a dry weight loss method, and the measured moisture content was constant at 10%. The value obtained by subtracting (excess moisture content not involved in internal moisture content) was employed.

(2) transparency

Finally, the prepared acrylic fiber was cut into a length of 2 mm, 105 mg of which was mixed with dimethyl phthalate with a refractive index of 1.512, acetophenone with a refractive index of 1.529, and ethanol with a refractive index of 1.358, with a refractive index of 1.506. After dispersing with the adjusted solution, the dispersion was prepared by putting a certain amount into a measuring vessel having a length × width × height = 1 × 1 × 5 cm, and received light having a wavelength of 420 mμ at right angles to the surface to measure the transmittance. Evaluated.

(3) △ K / S ratio

After dyeing Eisenkazilbul K-2GLH (Hododani Chemicals Cation Dye) to the measurement fiber, 0.5% owf (polymerization ratio of adsorbed dye to fiber dry weight) The water was divided into two and dried at 60 ° C for 60 minutes on one side and 120 ° C for 15 minutes at the other. Subsequently, the reflectance concentrations (K / S values) of the two dried dyestuffs were measured using a Hunter type reflectance photometer: a color machin-20 type (made by KK). ΔK / S ratio was calculated.

On the other hand, the numerical value of the denominator in the above formula indicates the reflection concentration of the dyeing material obtained according to the above-described prescription of the normal acrylic fiber, and as the ΔK / S ratio decreases, the degree of deterioration of color development of the final fiber decreases.

In addition, adjustment of the internal moisture content of the acrylic fiber in the hydrogel state in this invention is conventionally known as the component composition of the acrylonitrile-type copolymer or acrylonitrile-type polymer composition, this air in a spinning stock solution. Achievement is achieved by combining reconstitutions such as the concentration of the copolymer or the composition, the coagulation bath temperature at the time of release, the cold draw ratio and the hot draw ratio, and the like. , Amino group, amide group, ammonium base, etc.), when using the rhodan salt solution as the solvent, the concentration of the polymer or composition in the spinning solution is 8.0-13.0% by weight, the coagulation bath temperature at the time of release By adjusting the cold draw ratio to 1.5-3,0 times and the reheat draw ratio to within the range of 1.5-10 times at -3 ° C-10 ° C, Phase acrylic fiber can be obtained.

On the other hand, even in the case of using any spinning solvent, the amount of hydrophilic groups introduced into the fiber-forming polymer and the coagulation bath temperature are increased, or the polymer concentration, cold stretching ratio and thermal stretching ratio in the spinning stock solution are lowered. It goes without saying that the moisture content in the gel-like fibers can be effectively increased.

Moreover, as a manufacturing method of the halogen-containing acrylic solvent solution in this invention, the acrylonitrile-type polymer composition which mix | blended the acrylonitrile-type copolymer or halogen-containing flame-retardant component which finally copolymerized the halogen-containing unsaturated monomer, and acrylonitrile Any solvent may be used as long as a solvent solution of a known inorganic acid, inorganic salt or organic solvent is obtained as a solvent for the polymer. For example, (1) A method of dissolving an acrylonitrile-based copolymer obtained by copolymerizing acrylonitrile, a halogen-containing unsaturated monomer and other vinyl monomers copolymerizable with acrylonitrile in the solvent.

(2) a method in which a homopolymer of an acrylonitrile-based polymer and a halogen-containing unsaturated monomer or a copolymer of acrylonitrile or another vinyl monomer is mixed and then dissolved in a known solvent, or (3) acryl The method of adding and mixing a halogen containing organic compound to the acryl-type spinning stock solution which melt | dissolved a nitrile-type polymer with a solvent is employ | adopted. At this time, the polymer or copolymer of halogen-containing unsaturated monomer or halogen-containing organic compound blended as a halogen-containing flame retardant component may exist in such a solvent solution as well as exist in a dispersed state, but deviates from the gist of the present invention. no. In this context, the halogen-containing unsaturated monomer used in the present invention is an ethylenically unsaturated compound containing a halogen, and for example, acrylate, arylpromide, vinyl chloride, vinyl halide, vinylidene chloride and vinylidene halide. Halogenated unsaturated hydrocarbon-based monomers such as: Halogenated alkyl acrylates or methacrylates represented by 2,3-dichloromopropyl acrylate of acrylic acid or methacrylic acid: 2,4,6-tribromo phenyl acrylate, 2 Halogenated aryl acrylates or methacrylates such as, 6-dibromo-4-sulfonicphenyl acrylate and derivatives thereof: halogenated styrenes such as dibromostyrene; Nuclear substituted halogenated alkyl derivatives of styrene, such as P-chromomethyl or P-bromoethyl styrene: chloromethyl vinyl ether, bromomethyl vinyl ether, chloroethyl vinyl ether, bromoethyl vinyl ether, 2 Halogenated alkylvinyl ethers such as, 3-dichloroflofilvinyl ether, 2,3-promopropyl vinyl ether and the corresponding halogenated alkyl aryl ethers: bis (2-chloroethyl) vinyl phosphonate, bis (2-bromo Phosphorus and halogen-containing unsaturated monomers such as ethyl) vinylphosphonate, and the like. Among these halogen-containing unsaturated monomers, it is preferable to use halogenated unsaturated hydrocarbon monomers such as vinyl chloride, vinyl embrittlement, and vinylidene chloride.

In the present invention, as the halogen-containing organic compound introduced into the acrylic solvent solution, conventionally known halogenated organic compounds as flame retardants, such as tris (2,3-dibromopropyl) phosphate and tris (2,3-dichloropropyl ) Phosphate, tris (chlorobromoethyl) phosphate, tris (2-chloroethyl) phosphate, bisdibromo propyl dichloropropyl phosphate, bisbromochloropropyl propyl chloropropyl phosphonate, bis-2 Halogenated phosphates or phosphites such as chloroethyl vinyl phosphonate; Halogenated organic compounds, such as reaction products of halogenated and phosphorus oxyhalogenides, such as terroma epoxy compounds made from halomethane and unsaturated phosphates: halogenated aliphatic hydrocarbons such as tetrabromobutane, tetrabromoethane, chlorinated paraffin, hexa Halogenated aromatic hydrocarbons such as chlorobenzene; Halogenated aliphatic esters such as methyl pentachloride stearate, methyl pentachloride stearate, methyl pentachloride laurate, and ethyl pentachloride stearate; And halogenated fatty acid amides such as N, N-dimethyldibromostearamid and N, N-dimethyltetrabromostearamid.

기를 갖는 불포화 설폰산, 및 그 영(예 : 메타아크릴 설폰산, 스틸렌설폰산 및 그의 나트륨염, 카륨염); 1개의

기를 갖는 불포화지방족 탄화수소, (예 : 이소부틸렌등; 및 아크릴로니트릴과 공중하여 열 가소성 공중합체를 발생하는 1개의

기를 갖는 다수의 여타의 비닐, 아크릴 및 타의 화합물이 있다.Again, with other vinyl monomers used in the present invention. Vinyl esters, in particular vinyl esters of saturated aliphatic monovalent calphonic acids (eg vinyl acetate, vinyl propionate, vinyl butyrate); Aryl alcohols (e.g. arylalcohols, meraarylalcohols, etaacrylkilcols, etc.): aryl, methacrylic and other unsaturated monohydric alcohol esters of monobasic acids. (E.g. Aryl and metaaryl acetates, laurates, cyanates Etc); Acrylic acid and alk acrylic acid (e.g., methacrylic acid, etaacrylic acid, etc.) and esters and amides of these acids, such as methacrylates such as acrylates such as methyl, ethylpropylbutyl, acrylamide, methacrylamide, N-methyl Acryl amides such as -ethyl-furophyl-butyl and metaacrylamide; Methacrylonitrile, etaacrylonitrile, and other hydrocarbon substituted acryronitrile; 1

Unsaturated sulfonic acids having a group, and their spirits such as methacrylic sulfonic acid, styrenesulfonic acid and its sodium salt, carium salt; 1

Unsaturated aliphatic hydrocarbons having groups (e.g. isobutylene, etc.), and one which is copolymerized with acrylonitrile to generate a thermoplastic copolymer

There are many other vinyl, acrylic and other compounds with groups.

The amount of acrylonitrile in these acrylonitrile-based polymers or copolymers is suitably determined to include at least 40% by weight, preferably 60% by weight or more, of bound acrylonitrile in the finally obtained acrylic fiber, Copolymerization ratio or the amount of halogen-containing flame-retardant component is also appropriately determined to include 3-50% by weight in terms of halogen in the final acrylic fiber.

On the other hand, in the present invention, as a solvent for dissolving the halogen-containing acrylonitrile-based copolymer or halogen-containing acrylonitrile-based polymer composition to form a solvent solution, inorganic acid aqueous solutions such as concentrated acetic acid, rhodanso-darodan potassium, rhodan Rhodium salts such as anthocyanin and rhodancalcium, chlorite chlorates such as sodium perchlorate and calcium perchlorate, inorganic solutions such as zinc chloride and lithium chloride, and organic solvents such as dimethylformamide and dimethyl sulfoxide.

In addition, the concentration of the halogen-containing acrylonitrile-based copolymer or the halogen-containing acrylonitrile-based copolymer or the halogen-containing acrylonitrile-based polymer composition in the tactical solvent solution may maintain the internal moisture content of the gel acrylic fiber within a predetermined range. If possible, the conditions generally employed as described above may be arbitrarily selected.

Thus, the antimony oxide is uniformly dispersed in the prepared solvent solution, and a halogen-containing acrylic spinning stock solution is produced. The antimony oxide used in this invention requires that the average particle diameter is 100 micrometers or less. That is, the flame-retardant acrylic fiber produced by using antimony oxide as the acid average particle diameter exceeds 100 mμ is not preferable because its transparency is greatly deteriorated in non-water treatment processes such as dyeing. Moreover, the antimony oxide which concerns on this invention can be arbitrarily selected from antimony oxides, such as antimony trioxide, antimony tetraoxide, antimony pentoxide, or the catcher compound of antimony oxide thereof.

In addition, the mixer used for dispersing the above-mentioned antimony oxide in a solvent solution can be arbitrarily selected from a known stirrer. The acrylic radiation source solution in which the antimony oxide obtained according to the present invention is uniformly dispersed is formed into a thread as it is extruded in a coagulation bath according to a conventional method, and then subjected to a process such as cold drawing decoagulant treatment, hot drawing drying densification, and relaxation heat treatment. It is formed of fibers. On the other hand, the manufacturing conditions employed in such spinning and post-treatment processes are not subject to tight restrictions, and the gel fibers after thermal stretching are suitably determined under ordinary process conditions so as to maintain the internal moisture content in the range related to the present invention. will be.

The acrylic fiber obtained by wet spinning the halogen-containing acrylic spinning stock obtained by dispersing such antimony oxide particles not only has a high flame retardancy, but also the internal moisture retention of the gel acrylic fiber obtained by thermal stretching after wet spinning as described above. By adjusting the ratio to a predetermined range, the fiber performance of the final fiber, such as transparency, gloss, and chromite, is improved without any problem in the process, and the specificity is also special in comparison with conventional flame retardant acrylic fibers. I would say

The following Examples describe the present invention more clearly and do not limit the scope of the present invention. In the meantime, parts or percentages indicated in the examples are based on all weight standards unless otherwise specified.

Example 1

Antimony oxide particles having an average particle diameter of 15 mμ were prepared in an aqueous solution of monosodium-poly (50%) of acrylonitrile-based copolymer of 82.7% of acrylonitrile, 9% of vinylene chloride, 8% of methyl acrylate, and 0.3% of metharylsulfonate. It was continuously introduced in the polymer concentration of 10%) to 5.3% by weight of the copolymer, and mixed and stirred using a "pipeline homomixer-" (product made by a special vaporizer) as a stirrer to produce fine and A uniformly dispersed acrylic spinning stock solution was obtained continuously and stably.

The spinning stock solution thus obtained was extruded and solidified in -3 ° C., 12% rhodan small-water solution solidification using a pore diameter (孔徑 0.14mm air-spun 5028 spinneret), and cold drawn at room temperature for 2.5 times. The fibers in the state of water washing and hydrogel were stretched 4.8 times in boiling water, and then dried and densified at a temperature of 125 ° C., and again subjected to wet heat relaxation treatment with saturated steam at 128 ° C. to prepare final fibers. After stretching, the internal moisture content of the fibers in the hydrogel state was measured to be 64% for the fiber-forming polymer, and the final fiber did not generally have an empty space, and thus, no devitrification of the fiber was generally recognized. It possesses a good gloss and is also rich in commodity value which does not cause deterioration of the color development of the dyestuffs.The fiber performance of the flame retardant acrylic fibers obtained in this way is shown in the first table.

On the other hand, as the comparative example, the same antimony oxide particles as described above were used for the acrylonitrile copolymer (containing no hydrophilic group copolymer) containing 83.5% acrylonitrile, 7.7% methyl acrylate and 8.8% vinylene chloride. The final fiber was prepared by continuously introducing into a monosodium-aqueous solution (polymer concentration of 10%) at 50% and wet spinning, cold drawn thermal stretching, dry densification and relaxation heat treatment under the same conditions as the above method. The internal moisture content of the gel-like acrylic fiber in such a method, and the flame retardant performance of the obtained flame-retardant acrylic fiber are shown together in a 1st table | surface.

[Table 1]

As can be seen from the results in Table 1, by changing only the content of the hydrophilic group introduced into the fiber-forming polymer, the internal moisture content of the acrylic fiber in the hydrogel state was adjusted to within the range recommended in the present invention. In addition, a flame-retardant acrylic fiber having no chromogenic deterioration is obtained.

Example 2

Monosodium-polyaqueous solution was prepared with 50% of acrylonitrile-based copolymer of 83.8% of acrylonitrile, 6.7% of methyl acrylate, 8.8% of vinylidene chloride, and 0.7% of methacrylic sulfonic acid-dial with an adjusted polymer concentration of 9.5%. An acrylic spinning stock solution obtained by finely dispersing antimony oxide by the method of use and Example 1 was obtained. Again, this spinning stock solution was subjected to wet spinning, cold stretching, dry densification and relaxation heat treatment under the same conditions as in Example 1 to prepare final fibers. In this method, the internal moisture content of the gel acrylic fiber and the fiber performance of the obtained flame-retardant acrylic fiber are shown in the second table.

In addition, as a comparative example, by changing the acrylonitrile-based copolymer concentration to 10.5% to prepare a final fiber in the same manner as described above. In this method, the internal moisture content of the gel acrylic fiber and the performance of the obtained flame retardant acrylic fiber are also listed in Table 2.

[Table 2]

As can be seen from the results in Table 2, by adjusting only the concentration of the polymer in the spinning stock solution to adjust the internal moisture content of the gel acrylic fiber within the range recommended in the present invention, it is excellent in transparency gloss and no chromogenic chloride is generated. You will get acrylic fiber.

Example 3

Using an antimony oxide as in Example 1 and an acrylonitrile-based copolymer having the same composition as in Example 2, stirring was carried out as in Example 1 to obtain an acrylic radiation solution obtained by finely dispersing antimony oxide having a polymer concentration of 10%. Prepared. The spinning stock solution thus obtained was coagulated by extruding in a solidification bath of 12% rhodan soda solution using a spinneret as in Example 1, and then subjected to the same post-treatment as in Example 1 to prepare a final fiber. . In addition, the internal moisture content of the gel acrylic fiber after hot stretching was measured. The fiber content was 110% with respect to the fiber-forming polymer, and the final fiber was rich in product value with good gloss without voids. The fiber performance of the flame-retardant acrylic fiber obtained by this method is described in Table 3.

On the other hand, as a comparative example, only the coagulation bath temperature at the time of the release was changed to -3 ℃ to produce a final fiber in the same manner as described above. The internal moisture content of the gel acrylic fiber in this method and the performance of the obtained flame retardant acrylic fiber are also listed in Table 3.

[Table 3]

As shown in Table 3, by adjusting the moisture content of the acrylic fiber in the hydrogel state within a predetermined range according to the change of the coagulation bath temperature at the time of release, a flame-retardant acrylic fiber with improved fiber performance is produced.

Claims (1)

In a halogen-containing acrylic radiation stock solution obtained by dispersing antimony oxide having a particle size of 100 μm or less in a solvent solution of an acrylonitrile copolymer copolymerized with a halogen-containing unsaturated monomer or an acrylonitrile polymer composition containing a halogen-containing flame retardant component. In producing a flame-retardant acrylic fiber according to the conventional wet spinning method, the fiber performance, characterized in that the internal moisture content of the gel-like fiber obtained by heat stretching after wet spinning is adjusted to 50 to 130% by weight relative to the fiber-forming polymer. Improved flame retardant acrylic fiber manufacturing method.

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