JP2003301323A - Flame-retardant fiber and flame-retardant fiber composite therefrom - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-retardant fiber that can form totally excellent fiber composites by combining it with a melt type combustible polyester fiber. <P>SOLUTION: The flame-retardant fiber is modacrylic one made of a copolymer that includes 15-40 wt.% of halogen-containing vinyl monomers and has a molecular weight of 50,000-60,000. In a preferred embodiment, the flame- retardant fiber additionally contains an antimony compound in order to increase the flame-retardancy. The flame-retardant fiber is blended with a polyester fiber and the fiber blend is woven to produce the flame-retardant fiber composite. The resultant flame-retardant fiber composite has both of the cost merit of the polyester fiber and the design merit of the acrylic fiber. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant fiber composite comprising a halogen-containing modacrylic synthetic fiber and a melt-type combustible fiber and having a high degree of flame resistance and washing durability.

[0002]

2. Description of the Related Art Acrylic synthetic fibers are known as a material having a higher design than other synthetic fibers such as polyester. It is widely used for clothing, bedding, and interior applications. In recent years, in this field, the demand for ensuring safety is increasing, and the need for flame-retardant materials is increasing.
Under such circumstances, a method of imparting flame retardancy by combining flame-retardant fibers having high flame retardancy with general-purpose flammable fibers has been attempted. In particular, it is very advantageous in terms of cost and design to combine a halogen-containing modacrylic synthetic fiber with an inexpensive polyester fiber to form a flame-retardant fiber composite.

However, in a combination of melt-type combustible fiber such as polyester fiber and carbonized flame-retardant fiber such as acrylic, the carbonized fiber acts as a candle core, and the melt-type combustible fiber continues to burn. It is known that the so-called candle phenomenon occurs.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a flame-retardant fiber which can be woven with a melt-type combustible fiber, polyester, to form an excellent fiber composite as a whole.

[0005]

Means for Solving the Problems The inventors of the present invention have studied a technique for interweaving flame-retardant acrylic fibers and polyester fibers, and have completed a flame-retardant acrylic fiber optimal for interweaving with polyester fibers.

That is, the present invention contains a halogen-containing vinyl monomer in an amount of 15 to 40% by weight and has a molecular weight of 5000.
It is a flame-retardant fiber composed of a copolymer of 0 to 60,000.
It is also a flame-retardant fiber composite obtained by interwoven with the above fibers and polyester fibers.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The flame-retardant fiber of the present invention is characterized by comprising a copolymer containing 15 to 40% by weight of a halogen-containing vinyl monomer and having a molecular weight of 50,000 to 60,000. A more preferable copolymer composition is 50 to 85% by weight of acrylonitrile and 10% by weight or less of a vinyl-based monomer copolymerizable therewith.

If the content of halogen-containing vinyl monomer in the copolymer is less than 15%, the flame-retardant component is too small, and the flame-retardant property of the woven product with polyester fibers becomes insufficient.
When it exceeds 40%, the maximum shrinkage temperature of the spun yarn decreases,
It is not possible to suppress the candle phenomenon with polyester fibers. The range of halogen-containing vinyl monomer is 20-30%
Is preferred.

The copolymer used as the raw material for the flame-retardant fiber of the present invention must have a molecular weight of 50,000 to 60,000. The molecular weight referred to here is the viscosity average molecular weight converted from the measurement result of the solution viscosity of the polymer, as shown below. If this molecular weight is less than 50,000, the maximum shrinkage temperature of the spun yarn is lowered, and the candle phenomenon with the polyester fiber cannot be suppressed. On the other hand, if the molecular weight exceeds 60,000, there is a problem of operability such as single yarn breakage.

Specific examples of the halogen-containing vinyl-based monomer include vinyl chloride, vinylidene chloride, vinyl bromide, vinylidene bromide and the like. One or more of these are copolymerized with acrylonitrile. It can be used, but not limited to the above, any vinyl-based monomer containing halogen can be used. Above all, from the viewpoint of cost, vinyl chloride, vinylidene chloride (VD
C) is preferred.

Examples of vinyl monomers copolymerizable with the halogen-containing monomer include, for example, acrylic acid alkyl esters such as methyl acrylate and ethyl acrylate; methacrylic acid alkyl esters such as methyl methacrylate and ethyl methacrylate; Styrene, vinyl acetate,
Neutral monomers such as vinyl ethyl ether and methacrylonitrile; acidic monomers such as acrylic acid, methacrylic acid, allyl sulfonic acid, methallyl sulfonic acid, styrene sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid and the like of these monomers. Examples thereof include ammonium salts and alkali metal salts, but are not particularly limited as long as they are vinyl-based monomers copolymerizable with acrylonitrile-halogen-containing vinyl-based monomers. The vinyl-based monomers may be used alone or in combination of two or more. Among them, sodium methallylsulfonate and sodium 2-acrylamido-2-methylpropanesulfonate (SAM) are preferable from the viewpoint of designability.

A preferred composition of the flame-retardant fiber of the present invention essentially comprises 15 to 40% by weight of a halogen-containing vinyl-based monomer, 50 to 85% by weight of acrylonitrile, and 0 to 10% by weight of a vinyl-based monomer copolymerizable therewith. Is included. More preferably, the content of the vinyl monomer as the third component is preferably 0.5 to 5% by weight.

Further, it is preferable to add an antimony compound to the flame-retardant fiber of the present invention. Specific examples of the antimony compound include, but are not limited to, inorganic antimony compounds such as antimony trioxide, antimony tetraoxide, antimony pentoxide, antimonic acid, and antimony oxychloride. Among these, antimony trioxide is oxygen blocking by antimony oxyhalide formation over a wide range from 245 ° C. near the thermal decomposition initiation temperature of the acrylonitrile-based polymer of the present invention, followed by continuous halogen supply by antimony trihalide formation, and It is the most preferable flame retardant because it has the effect of dehydrohalogenation from the base polymer and the effect of promoting char formation.

When an antimony compound is used,
The particle diameter is important, and in view of spinnability, generated static electricity, spinnability, dyeability, etc., it is preferably 3 μm or less. More preferably, it is 1.5 μm or less.

When an antimony compound is added,
It is preferable that 0.1 to 5.0% is contained in the fiber.

The acrylonitrile polymer used in the present invention may be polymerized by any known method such as suspension polymerization, solution polymerization and emulsion polymerization.

Next, the flame-retardant fiber composite of the present invention will be described. The flame-retardant fiber composite of the present invention is a mixture of the acrylic (modacrylic) flame-retardant fiber and the polyester fiber in a mixed weave. The mixing ratio of flame-retardant fiber and polyester fiber is not specified, but in order to express high flame-retardant performance,
As the polyester fiber which can be used, a general polyester fiber containing PET (polyethylene terephthalate) as a main component may be used, and a regular yarn and a processed yarn,
Examples include those that have undergone special processing.

The reason why the flame-retardant composite of the present invention has excellent flame retardancy is that the flame-retardant fiber made of a copolymer containing halogen is
It is presumed that the fiber has a maximum shrinkage temperature close to that of polyester fiber, so that the fiber can be efficiently shrunk at the time of combustion, can be quickly moved away from the fire source, and can escape the spread of fire. If the maximum shrinkage temperature of the flame-retardant fiber is significantly higher or lower than that of polyester, the shrinkage of the fabric does not proceed uniformly, so that it cannot be quickly moved away from the fire source.

The flame-retardant fiber of the present invention can be used alone, but its effect is maximized when it is mixed with the polyester fiber. Further, the flame-retardant fiber composite of the present invention,
It is used for clothing, bedding, and interior applications, and is particularly suitable for interior applications such as curtains and upholstered chairs.

[0020]

The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. Before describing the examples, evaluation methods for various characteristic evaluations will be described.

(1) Measurement of molecular weight An Ostwald viscosity tube was used to measure the molecular weight. Raw cotton is used as a measurement sample, and 200 mg of raw cotton is dissolved in 50 ml of dimethylformamide (DMF), and the solution viscosity is 30 ° C.
Was measured in a constant temperature bath and converted into a molecular weight. Conversion formula Mw = (ηsample / ηblank-1) × 53/6
× 10 ⁴ Here, Mw: molecular weight, η sample: viscosity of sample solution (s), η blank: viscosity of solvent only (s).

(2) Flame-retardant test The flame-retardant test was carried out in accordance with the fire-fighting test method 45 ° tarmac method 60 seconds heating method. The woven cloth used was both unwashed and washed. The burning direction of the woven fabric was from the four directions of the front and back of the cloth. In the combustion test from the front and back 4 directions, even one piece was completely burned (flame reached the frame supporting the woven cloth), and the woven cloth was rejected (x). The product was passed (○). (3) Evaluation of operability When a single yarn breakage or winding around the roller occurred during the operation, it was judged as fail (x), and when no problem occurred, it was judged as pass (◯).

Examples 1 and 2 and Comparative Examples 1 and 2 The mass ratio of acrylonitrile / vinylidene chloride / 2-acrylamido-2-methylpropanesulfonic acid sodium was 5
A monomer mixture of 7/40/3 was dissolved in DMF to a monomer concentration shown in Table 1, and solution polymerization was carried out at a temperature shown in Table 1 using azobisdimethylvaleronitrile as a polymerization initiator to obtain residual monomers. Was removed. afterwards,
The concentration of acrylonitrile polymer was adjusted to 20 to 30%. The flame retardant Sb ₂ O ₃ uses DMF as a dispersion solvent and has a concentration of 3
Adjusted to 5% by weight. The obtained Sb ₂ O ₃ dispersion was added to the acrylonitrile-based polymer so that the Sb ₂ O ₃ concentration was 3% by weight to prepare a spinning dope. DM the above spinning solution
After wet spinning in an F aqueous solution, post-treatments such as washing with water, application of an oil agent, drying and densification by drying, crimping, wet heat setting, and cutting were performed.

The molecular weight of each raw cotton was confirmed and spun with a metric count of 17 and the spun yarn obtained was 40 wefts /
A woven fabric was prepared with 2.5 cm and warp polyester 165 dtex Woolly yarn 130 / 2.5 cm. Table 1 shows the results of the flame retardance evaluation of the woven fabric and the results of the operability evaluation.

[0025]

[Table 1]

As shown in Table 1, in Examples 1 and 2,
It satisfied both flame retardancy and operability. Molecular weight 4500
In Comparative Example 1 of 0, sufficient flame retardancy was not obtained, and the test failed. Comparative Example 2 having a molecular weight of 70,000 had high flame retardancy as in Examples 1 and 2, but had a problem in operability and was rejected.

Examples 3 to 5 and Comparative Examples 3 and 4 In the preparation of acrylonitrile-based polymers, Table 2 shows a monomer mixture of acrylonitrile / vinylidene chloride / 2-acrylamido-2 methylpropanesulfonic acid using DMF as a solvent. As described above, it is dissolved in DMF, and solution polymerization is carried out using azobisdimethylvaleronitrile as a polymerization initiator.
The residual monomer was removed. Then, the concentration of the acrylonitrile polymer was adjusted to 20 to 30%. Flame retardant S
b ₂ O ₃ was adjusted to a concentration of 35% by weight using DMF as a dispersion solvent. The obtained Sb ₂ O ₃ dispersion solution was added to the acrylonitrile-based polymer so that the Sb ₂ O ₃ concentration was 3% by weight, to prepare a spinning dope. After the above spinning solution was wet-spun in a DMF aqueous solution, it was subjected to post-treatments such as washing with water, application of an oil, drying and densification by drying, crimping, wet heat setting, and cutting.

This raw cotton was spun at a metric count of 17 and the resulting spun yarn was 40 wefts / 2.5 cm, warp polyester 165 dtex Woolly yarn 130/2.
A woven fabric was made with 5 cm. Table 2 shows the pass / fail results of the flame retardancy evaluation of the woven fabric.

[0029]

[Table 2]

As shown in Table 2, VDC of Example 3
Since the maximum shrinkage temperature of the spun yarn having an amount of 15% by weight is close to that of polyester, when the woven fabric is used, the spun yarn shows high flame retardancy in spite of a small amount of the flame retardant component.
Woven fabrics using spun yarns by weight are burned down. Although the woven fabric using the spun yarn with the VDC amount of 40% by weight of Example 4 exhibits high flame retardancy, the VDC amount of Comparative Example 4 is 50% by weight.
The spun yarn is burned down despite its high flame-retardant content, probably because it is much lower than the maximum shrinkage temperature of polyester.

[0031]

The flame-retardant fiber composite of the present invention exhibits excellent flame-retardant properties in the combination of carbonized acrylic fibers and melt-type polyester fibers, which is usually difficult to obtain flame-retardant properties. It is possible to provide flame-retardant interior textile products with excellent design and cost.

Claims (4)

[Claims] 1. A halogen-containing vinyl-based monomer of 15 to
A flame-retardant fiber comprising a copolymer having a molecular weight of 50,000 to 60,000 containing 40% by weight. 2. The flame-retardant fiber according to claim 1, wherein the copolymer further contains 50 to 85% by weight of acrylonitrile and 0 to 10% by weight of a vinyl monomer copolymerizable therewith. 3. The flame-retardant fiber according to claim 1, which contains an antimony compound. 4. A flame-retardant fiber composite obtained by interwoven with the flame-retardant fiber according to claim 1 and a polyester fiber.