JP2519185B2 - Flame-retardant acrylic composite fiber - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a flame-retardant acrylic composite fiber having excellent flame retardancy and latent crimp development.

(Prior Art) Conventionally, general acrylic fibers have a bulky feel similar to wool, excellent physical properties, and solid dyeability and dye sharpness, and have been used in a wide range of applications. However, since acrylic fibers are flammable like most natural and synthetic fibers, their demand range is such that they aid the spread of fire in applications such as clothing, interior products and industrial and construction applications. It was narrowed down. On the other hand, flame-retardant acrylic fiber has the properties of flame retardancy and self-extinguishing property, but it does not reach the level of ordinary acrylic fiber in terms of product luster, bulkiness, and settling, and is still used in sufficient quantity. It is not the situation. Therefore, in flame-retardant acrylic fiber products,
As a method of improving the above drawbacks, it is common practice to use a blend of other fibers having excellent physical properties, such as nylon, polyester, and polyacrylonitrile fibers, but the blending increases the number of processing steps and the dyeability. Inconveniences such as a reduction in the texture, a change in the texture, and a decrease in the flame retardancy arise.

In order to improve the bulkiness, waistness, settling, etc. of products made of flame-retardant acrylic fibers alone, shrinkable cotton with the same flame retardancy and fibers with latent crimpability, especially the latter, are necessary. Yes, this product has flame retardancy by mixed use of flame-retardant acrylic fiber with latent crimping property and ordinary flame-retardant acrylic fiber, and has good waist feeling, bulkiness, texture, dyeability, etc. Can be manufactured. However, a flame-retardant acrylic composite fiber having both good potential crimpability and flame retardancy has not been obtained so far, and its study has not been conducted so much. JP-A-49-68014 is a composite fiber of a polyacrylonitrile-based polymer containing 85% by weight or more of acrylonitrile, a flame-retardant acrylic polymer and an antimony halide compound, and the fiber obtained here. Since the polyacrylonitrile polymer is used as one component, the flame retardancy cannot be sufficiently enhanced. If the vinyl chloride content or antimony halide content in other components is increased to increase the flame retardancy, gelation in the spinneret or clogging of the spinneret due to differences in miscibility and compatibility between both components, Thread breakage occurs, and the coagulation properties of both components are greatly different, so that it is difficult to set coagulation bath conditions that allow both components to coagulate densely. Further, even after spinning, due to insufficient adhesion between both components, it is expected that the operability and quality will be greatly reduced, such as the occurrence of troubles due to peeling of both components due to stretching / shrinkage ratio. In addition, it is expected that the products will have lower consumption performance such as dyeability, heat resistance, and gloss, and processing performance such as yarn breakage during spinning, weaving, and feathering. JP-A-59-82410 is a composite fiber obtained by adding a polyurethane polymer to a flame-retardant acrylic polymer and spinning the fiber. However, the fiber obtained here only increases the cost of the fiber due to the added polyurethane polymer. However, the coloring properties and light resistance after dyeing were not yet satisfactory.

(Problems to be Solved by the Invention) As described above, a flame-retardant acrylic composite fiber using a flame-retardant acrylic polymer for both components and having sufficiently good flame retardancy and latent crimpability has not yet been developed. Not. The reason for this is that flame-retardant acrylic fiber has a large amount of halogen-containing monomer or other flame-retardant agent to improve flame-retardant property, which is a kind of plasticizer for fibers of flame-retardant compound. The reason is that even if the amount of the plastic component (for example, a halogen-containing monomer) between the two components of the composite fiber is changed by a small amount, the one having sufficient latent crimpability cannot be obtained. If the difference in the amount of the plastic component of both components is expanded so that sufficient latent crimping property is expressed, the flame retardancy of the fiber decreases and conversely there is flame retardance, but the heat resistance decreases, strength decreases, dyeing As a result, there is a decrease in quality such as a decrease in workability, or a decrease in spinnability, a decrease in strength, and a decrease in heat resistance, resulting in a decrease in operability.

As a result of earnest studies to overcome the above-mentioned drawbacks, the present inventors have
The present invention has been completed.

The object of the present invention is good texture, bulkiness,
An object of the present invention is to provide a flame-retardant acrylic composite fiber having an excellent latent crimping property with a feeling of stiffness.

(Means for Solving the Problems) That is, according to the present invention, both components A and B are joined eccentrically, and (a) the component A comprises 40% by weight or more of acrylonitrile, a halogen-containing monomer and a sulfonic acid-containing monomer 20. To (60)% by weight of the polymer (I), and (B) the component B is 95 to 60 parts by weight of the component A polymer (I) based on the polymer of glycidyl methacrylate and / or its copolymer. A flame-retardant acrylic conjugate fiber comprising a polymer composition obtained by mixing 5 to 40 parts by weight of the following polymer (II).

Examples of the halogen-containing monomer in the polymer (I) of the present invention include vinyl chloride, vinylidene chloride, vinyl bromide and vinylidene bromide, but are not limited thereto. Vinyl chloride and vinylidene chloride are particularly preferable.
If the content of halogen-containing monomer is less than 20% by weight, excellent flame retardancy cannot be obtained, and if it exceeds 160% by weight, not only the heat resistance and strength of the obtained fiber are deteriorated, but also the flame retardance is saturated. It is not economical. Therefore, the amount of the halogen-containing monomer is preferably in the range of 20 to 60% by weight in view of operability, quality and cost.

In the present invention, examples of the sulfonic acid-containing monomer include sodium allyl sulfonate, sodium methallyl sulfonate, sodium styrene sulfonate, sodium 2-acrylamido-2-methylpropane sulfonate, but are not limited thereto. . When the polymer (I) contains 0.5 to 5% by weight, preferably 1 to 4% by weight of these sulfonic acid-containing monomers, the dyeing property is improved, the coagulability during spinning is greatly improved, and the dry densification is improved. It can be greatly improved and promoted, and a fiber having good gloss and dyeability can be obtained.

In the present invention, the polymer (II) is a glycidyl methacrylate homopolymer and / or copolymer. The copolymer may be a copolymer of 25% by weight or more of glycidyl methacrylate and 75% by weight or less of a monomer having one or more kinds of double bonds copolymerizable therewith. Examples of the monomer having a double bond include acrylonitrile, vinylidene chloride, vinyl chloride, esters of acrylic acid, esters of methacrylic acid, acrylamide, methacrylamide,
Examples thereof include sulfonic acid-containing monomers such as vinyl acetate, sodium allylsulfonate, sodium methacrylsulfonate, and sodium 2-acrylamido-2-methylpropanesulfonate.

In the present invention, the mixing ratio of the polymer (II) to the polymer (I) of the component B is 5 to 40 parts by weight, preferably 7 to 30 parts by weight, more preferably 10 to 25 parts by weight. When the amount of the polymer (II) is less than 5 parts by weight, the number of crimps developed in the fiber in which both components A and B are composite-spun is insufficient. On the other hand, if it exceeds 40 parts by weight, the fibers obtained by composite spinning of both the A and B components will increase in stickiness and the number of crimps will increase too much, resulting in poor texture when used in a mixed spinning.

The polymer used in the present invention can also be prepared by a conventional polymerization method such as emulsion polymerization or suspension polymerization in an aqueous medium or an aqueous medium containing an organic solvent, or solution polymerization. As the catalyst used for the polymerization, a usual radical polymerization initiator, for example, a persulfate salt, or a combination of a persulfate salt and an acidic sulfite or a salt thereof, an azo compound such as azobisisobutyronitrile, benzoyl peroxide, etc. There is no particular limitation, such as a peroxide.

Further, as the method for producing the fiber of the present invention, any of ordinary wet and dry methods is possible, and the solvent of the spinning dope is dimethylformamide, dimethylsulfoxide, dimethylacetamide, acetone which is a solvent of an ordinary acrylonitrile polymer. , Acetonitrile, etc. are used.

It is also possible to add and spin a heat and light resistance stabilizer or a flame retardant aid such as antimony trioxide, antimony pentoxide, metastannic acid, etc. to the fiber of the present invention.

Next, the present invention will be described in more detail with reference to an example of a method for producing the fiber of the present invention.

The polymer (I) is 20 to 60% by weight of a halogen-containing monomer consisting of vinyl chloride, vinylidene chloride, vinyl bromide or a mixture thereof, acrylonitrile, and a small amount (for example, 0.5 to 5% by weight) of sodium acrysulfonate, styrene sulfone. Sodium acid or 2-acrylamide
Polymerization of a dye-improving monomer such as sodium 2-methylpropanesulfonate with a polymerization initiator such as azobisisobutyronitrile and azobisdimethylvaleronitrile in an organic solvent such as dimethylformamide, dimethylsulfoxide or dimethylacetamide. Let it. Particularly preferably, sodium allyl sulfonate 5 to 40% by weight, acrylonitrile 10 to 85% by weight, halogen-containing monomer 10 to 50%
% By weight of a polymer having a composition of 20% to 60% by weight in a dimethylformamide solution containing the polymer, and 20 to 60% by weight of a halogen-containing monomer and acrylonitrile and, if necessary, allyl. The sodium sulfonate is polymerized in the presence of other additives, such as color inhibitors. The unreacted monomer in the obtained polymerization dope is removed by a rotary evaporator or a rotating thin film evaporator at a temperature as low as possible, and thereafter, the polymer concentration is adjusted to 20 to 30% by weight, and additives are added. A spinning dope of the polymer (I) is obtained.

On the other hand, as the polymer (II), a homopolymer of glycidyl methacrylate and / or a copolymer of glycidyl methacrylate of 25% by weight or more and a monomer having a copolymerizable double bond of 75% by weight or less is used as an ordinary polymer. Polymerize legally,
Make a 20-30 wt% dope of dimethylformamide.

Next, the stock solution of the polymer (I) is used as the component A, and the solution of the polymer (II) having a polymer concentration of 20 to 30% by weight is added to the stock solution of the polymer (I) and mixed. Obtain a stock solution.
Each spinning dope is kept at 40 to 60 ° C. in order to adjust spinning viscosity and improve spinnability, and is led through separate inlets to a conjugate fiber die. The base is usually a side-by-side type composite base. The hole diameter and the number of holes of the nozzle of the die are determined by the single yarn denier, but if it is about 8 denier, it is usually 0.05 to 0.
Use a hole with a diameter of 08 mm. For the coagulation bath, an aqueous solution of an organic solvent used for the spinning solution, an organic solvent such as isopropyl alcohol, ethylene glycol, or polyethylene glycol or an aqueous solution thereof is usually used. The composition, temperature and the like may be the same conditions as in the case of producing the flame-retardant acrylic fiber, or may be conditions under which the solidification is slightly accelerated. When dimethylformamide is used as the solvent of the spinning solution, the coagulation bath conditions are preferably an aqueous solution having a dimethylformamide concentration of 45 to 65% by weight and a temperature of 30 ° C. or less.

The spun fibers are usually subjected to a primary drawing of about 4 to 8 times in several baths in which the concentration of organic solvent is gradually lowered, followed by washing with water and pre-oil treatment. Next, drying and densification are performed using hot air of 100 to 180 ° C., a hot roller, or a combination of hot air and a hot roller. After drying or after primary stretching, secondary drying is performed before drying to adjust fiber properties. Two
The next stretching is performed about 1.05 to 2 times in hot water or steaming. After secondary stretching, shrinkage, stretching, post-oil, mechanical crimping, crimp setting, etc. may be performed to improve crimp development, adjust fiber properties, adjust texture, and improve spinnability.

(Effect of the invention) The flame-retardant acrylic composite fiber according to the present invention thus obtained is a fiber having both good flame retardancy and latent crimpability, and has a high degree of flame retardancy, bulkiness, and good wind. , Safety of blankets, sheets, bedspreads, carpets, curtains, etc.
It is capable of exerting its performance sufficiently in clothes for children and elderly people who require comfort, especially in pajamas and the like.

(Example) Next, the present invention will be specifically described with reference to examples. still,
Parts and% in Examples are parts by weight and% by weight unless otherwise specified.
Indicates.

 The crimp property was measured according to JIS L-1074.

Flame retardancy was expressed by the limiting oxygen index (hereinafter abbreviated as LOI). The fiber is cut into 51 mm, defibrated with a hand card and about 0.5 g of cotton is sampled. Evenly stretched to a length of about 25 cm, twisted 40 times with a twisting machine and folded in two. To make a twisted rod. Next, a flame is brought into contact with the upper end of the twisting rod in a mixed gas of nitrogen gas and oxygen gas, and the oxygen gas concentration (volume) in the mixed gas when the sample burns by 5 cm is represented by the following formula.

Example 1 Acrylonitrile (hereinafter abbreviated as AN): vinylidene chloride (hereinafter abbreviated as VDC): sodium allyl sulfonate (hereinafter abbreviated as SAS) = 57: 30: 13 (%) was used as a polymer having a composition of dimethylformamide (hereinafter abbreviated). Polymerization was carried out in an autoclave using azobisdimethylvaleronitrile as an initiator with DMF (abbreviated as DMF) as a solvent. Next, 3 parts of this polymer, 28 parts of AN, and 24 parts of VDC were dissolved in 45 parts of DMF, and then a small amount of zinc paratoluenesulfonate was added as an anti-blocking agent, and azobisdimethylvaleronitrile was used as an initiator in an autoclave.
Polymerization was carried out at 55 ° C. for 9 hours to obtain a polymer (I) having a composition of AN / VDC / SAS = 53/44/3. The polymerization dope was evaporated by vacuum using a rotary evaporator to remove and recover unreacted monomers. After the monomer recovery, the polymer solution was transparent, pale yellow and viscous. Water / DMF to this viscous dope
The mixed solution was added to obtain a spinning solution for polymer (I) having a polymer concentration of 23.5% and a water content of 4.5%.

Next, a stock solution of polymer (II) having a polymer concentration of 23.5% was obtained from a homopolymer or copolymer of glycidyl methacrylate (hereinafter abbreviated as GMA) obtained by DMF-based solution polymerization. The stock solution of the polymer (II) was mixed with the stock solution of the polymer (I) such that the weight ratio of each polymer was as shown in Table 1 to obtain a stock solution of the component B.

With the polymer (I) as the component A, the spinning solution of the components A and B is a side-by-side type composite spinneret (nozzle hole diameter 0.06).
mm, 4000 holes), each introduced from a separate inlet, DMF:
Water = 53:47 (%) spun into a coagulation bath at 18 ° C. The discharge ratio of the A and B components is 1: 1. The spun fiber has a DMF concentration of 30.
% And 15%, the solvent is removed and the primary stretching of 4.5 times is performed in two baths, followed by thorough washing in a 70 ° C water washing tank and adhesion of oil in the previous oil tank, then 135 ° C. It was dried and densified with a hot roller. After drying, it undergoes a secondary stretch of 1.4 times by steaming at 110 ° C and a tension / shrinkage of 0.95 times under steaming at 125 ° C. After oil is attached and a clamp is applied, it is dried.
Various flame-retardant acrylic composite fibers of denier were obtained.

Example 2 A polymer having a composition of 48.5% by weight of acrylonitrile, 10% by weight of vinylidene chloride, 40% by weight of vinyl chloride and 1.5% by weight of methallylsulfonic acid was polymerized by emulsion polymerization in an autoclave.

This polymer was dissolved in acetone to obtain a spinning solution for polymer (I) having a polymer concentration of 30% and a water content of 3%. The spinning solution of the polymer (I) is the component A, and the component B is the polymer (I).
A spinning stock solution was obtained by adding 15% by weight of a homopolymer of glycidyl methacrylate having a polymer concentration of 30% by weight dissolved in acetone to the spinning stock solution.

Each spinning solution was introduced into a side-by-side type composite spinneret having a pore size of 0.07 mm from separate inlets, and spun into a coagulation bath of a 35% aqueous acetone solution. After washing with water, dry at 120 ℃, at 100 ℃
Stretching at 1.8 times and tension / shrinkage at 0.95 times at 100 ° C. were performed, after which oil was attached, crimp was applied, and then dried to obtain 3d fibers.

This fiber shows good dyeability without fiber sticking,
LOI is 28 flame retardant and the number of winding occurrences after boiling water is 20 /
It was inches.

Claims (3)

(57) [Claims] 1. A polymer in which both components A and B are joined eccentrically, and (a) a polymer in which component A comprises 40% by weight or more of acrylonitrile and 20 to 60% by weight of a halogen-containing monomer and a sulfonic acid-containing monomer ( (B) Component B is 5-40 parts of polymer (II) consisting of a polymer of glycidyl methacrylate and / or its copolymer, relative to 95-60 parts by weight of component A polymer (I). A flame-retardant acrylic conjugate fiber which is a polymer composition mixed in parts by weight. 2. The fiber according to claim 1, wherein the halogen-containing monomer is vinylidene chloride and / or vinyl chloride. 3. The sulfonic acid-containing monomer of polymer (I) is
The fiber according to claim 1, which is 0.5 to 5% by weight.