JPS59204918A - Flame-retardant acrylic synthetic yarn - Google Patents

Abstract

PURPOSE:Novel acrylic synthetic yarn satisfying high flame retardance, improved gloss and transparency, obtained by adding a halogen-containing inorganic tin compound to a copolymer of acrylonitrile-vinyl monomer system. CONSTITUTION:For example, 1wt% (calculated as content in yarn) halogen-containing inorganic tin compound (e.g., stannous chloride, stannic chloride, stannic bromide, etc.) is added to a spinning stock solution consisting of 30-70wt% acrylonitrile, 70-30wt%, halogen-containing vinyl monomer (e.g., vinyl chloride, vinylidene chloride, etc.), and 0-10wt% vinyl monomer copolymerizable with them [e.g., (meth)acrylic acid, etc., preferably at least one of the monomers is sulfone group-containing vinyl monomer such as methallylsulfonic acid, etc.], and the solution is spun, to give the desired yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel acrylic synthetic fiber having a high degree of flame retardancy and excellent gloss and transparency.

Traditionally, so-called modacrylic fibers, which are copolymerized with a relatively large amount of vinyl halide, have some degree of flame retardancy, but social demands for flame retardancy are rapidly increasing due to recent hotel fires. -Nowadays, there is a demand for delicate materials with better flame retardancy. Methods for imparting flame retardancy to fibers include copolymerizing flame retardant monomers, adding and mixing flame retardants to the spinning dope and spinning them later, and attaching flame retardants during post-processing. etc. are known.

Generally, a method of adding a flame retardant to the spinning dope is often used because it can impart flame retardance semi-permanently without impairing the physical properties of the fiber of the comparison source. As a flame retardant,
Although various kinds of compounds are known, such as halides containing chlorine and bromine, nitrogen-containing and phosphorous compounds, and other metal compounds, there are few that are effective in making acrylic synthetic fibers flame retardant. Among them, metal oxides such as tin oxide, antimony oxide, and magnesium oxide are relatively effective in improving the flame retardancy of acrylic synthetic fibers, but because they are unnecessary as solvents, the permeability of the fibers is significantly reduced. It has the disadvantage of not being able to obtain ropes (lower quality swords). Furthermore, when manufacturing fibers, it has the disadvantage of increasing the pressure during filtration of the spinning solution and easily clogging the nozzle.
It is extremely difficult to develop synthetic fibers that satisfy both transparency and the reality is that no satisfactory product has yet been obtained.

The present inventors have conducted extensive research to find an acrylic synthetic fiber that eliminates these drawbacks and satisfies both high mP properties and excellent gloss and transparency, in view of the actual situation described in 7:l), and as a result, the present invention has been developed. has been reached.

That is, the present invention relates to an acrylic synthetic fiber comprising a polymer composed of acrylonitrile and a vinyl monomer copolymerizable therewith, and containing a halogen-containing inorganic tin compound.

The acrylic synthetic fibers related to the present invention are not only used in various textile products like general acrylic synthetic fibers, but also in product groups that require a high degree of flame retardancy, such as interior decorations such as curtains and carpets. Products, toys, clothing for the elderly such as night clothes, children's items, hospital bedding, as well as wool, animal hair-like filament I-+ yarn, bedding, and high pile, which are preferred for their excellent gloss, transparency, dyeability, and texture. It is also suitable for

The synthetic fiber referred to in the present invention is an acrylic synthetic fiber made of a polymer whose main component is acrylonitrile, and the polymer contains 30 to 70% by weight of acrylonitrile.
(hereinafter simply abbreviated as %), it is preferably a copolymer composed of 70 to 30% of a halogen-containing vinyl monomer and 0 to 10% of a vinyl monomer copolymerizable with these. The halogen-containing vinyl monomer mentioned here is, for example, at least one type of monomer selected from vinyl chloride, vinylidene chloride, vinyl bromide, vinylidene bromide, etc., and vinyl that can be copolymerized with r+J. The monomers include acrylic acid, Melit J/IJ le and Sowara salts and esters, acrylamide, methacrylamide,
Examples include vinyl acetate, but at least one copolymerizable vinyl monomer is a vinyl monomer containing a sulfonic acid group, such as methallyl sulfonic acid, styrene sulfonic acid, and salts thereof. It is more preferable to do so.

The halogen-containing inorganic tin compound referred to in the present invention is
Tin, stannic chloride, stannic bromide, tin oxychloride (
I), soot oxychloride (JV), etc.

The method for producing the acrylic synthetic fiber of the present invention is not particularly limited, but for example, in the polymerization system for obtaining the polymer that is the base material of the fiber, in the polymerization reaction mixture, or in the spinning dope. There are methods of incorporating halogen-containing inorganic tin compounds into fibers by adding or producing halogen-containing inorganic tin compounds, and of course additives to further improve the properties of the fibers may also be included. Needless to say, there is no harm in doing so. In addition, when the halogen-containing inorganic tin compound is added as a water bath liquid or a water mixture, the particle size of the halogen-containing inorganic tin compound contained in the fiber becomes smaller as the concentration of the aqueous solution or water mixture becomes thinner. By force and combing, the concentration of the aqueous solution or aqueous mixture is 30% or less, more preferably 1
It is desirable that it be 5% or less.

By smelling, the average particle size of the halogen-containing inorganic tin compound contained in the fibers can be reduced to about 100 rnμ or less, making it possible to obtain fibers with extremely excellent gloss and transparency.

The reason why the fibers of the present invention have good gloss, transparency, and flame retardance is not necessarily clear, but the halogen-containing inorganic tin compound is compatible with the acrylic polymer that is the fiber base material and the solvent for this polymer. Because it has extremely good coexistence and affinity, it can exist in a microscopic state in the fiber, does not interfere with light transmission, has a large surface area, and does not contain halogen. It is thought that it functions effectively as a flame retardant.

The flame retardant evaluation of the fibers in the present invention was carried out using the oxygen index method.

That is, in the oxygen index method, a 25-inch piece of filament 1 with a total fineness of 5,400 deniers is taken, twisted 75 times, combined into two pieces, and reverse-twisted 45 times (7111) to obtain a silk-like sample. The sample was heated at 170°C for 5 minutes and placed upright in the holder of the oxygen index sampler.
Measurements were made of the percent oxygen required to keep burning. The larger the number indicated by the oxygen index method, the more history 1
It is highly flammable. The oxygen index, its combustion state, and the sample after combustion were observed, and a comprehensive evaluation of flame retardancy was performed based on the evaluation criteria listed in F.

◎: Very good flammability.

0: Excellent flame retardancy. , △: Poor flame retardancy.

X: Almost no flame retardancy, poor.

The transparency of the fiber is determined by dissolving the fiber sample in dimethylformamide as a 5% solution, and determining the wavelength of the solution at 6.
Measure the light transmittance at 50 mμ with a spectrophotometer,
The comparison was made with the transmittance of dimethylformamide as 100.

The metallic tin content referred to in the present invention is the amount of tin contained in a sample measured by atomic absorption spectrometry according to a conventional method.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1, Comparative Examples 1 to 2 Acrylonitrile (hereinafter abbreviated as A and N), vinylidene chloride (hereinafter abbreviated as F and V'D), vinyl chloride (hereinafter abbreviated as F-V
(abbreviated as C), sodium methallylsulfonate (hereinafter referred to as S
MS), 0.3% sodium lauryl sulfate aqueous solution,
Emulsion polymerization was performed using ammonium persulfate.

This polymerization reaction mixture 5A; 1 polymer content 22%, polymer composition A N 48.2%, vDat, o%, \/C
Add and mix 10% tin water m solution (1.1%, 9.7%, SMS 1.1%) as specified, and adjust p II to 6 using caustic soda. -, further salting out using a common salt bath and washing were performed to obtain a polymer.

Mix this polymer with acetone to a concentration of 30%.
Spinning B: 4J i? As l, the pore diameter is 0"" m
, spinning with 300 holes] from gold was discharged into a 25% acetone water bath without pressure increase or nozzle clogging, and through the usual steps of water washing and drawing, a single 3-denier filament was obtained. Example 1 And so.

On the other hand, for comparison, as Comparative Example 1, the polymerization reaction mixture of Example 1 was taken out only the polymer without adding tin tetrachloride and spun as a spinning stock solution, and as Comparative Example 2,
Mexusic acid (average particle size 1.5 I) was added to the spinning stock solution of Comparative Example 1.
A filament spun with the same amount of metal tin content as the filament of Example 1 was also evaluated at the same time. The results are shown in Table 1.

Table 1 From Table 1, the fiber of Example 1 efficiently contains tin chloride (IVI) and has not only extremely good flame retardancy but also excellent gloss and transparency. Furthermore, it is also excellent in general fiber properties such as white skin and dyeability.

On the other hand, Comparative Example 1 does not contain an inorganic tin compound, so as expected, the gloss and transparency are good, but the flame retardance is poor. On the other hand, Comparative Example 2, which is a conventional flame-retardant fiber, has excellent flame retardancy, but the fibers become white due to the flame retardant particles and have poor transparency.

Examples 2 to 7, Comparative Examples 3 to 8 Emulsion polymerization was carried out in the same manner as in Example 1, and the polymer composition was AN5.
6. A polymerization reaction mixture containing 20% of a polymer consisting of O%, V D 42.9%, and 5M 54.1% was obtained.

51 cg of each of this polymerization reaction mixture was added and mixed with a lO% tin dichloride water mixture so that the metal tin content shown in Table 2 was contained in the fibers, and pl
( was adjusted to 4 to salt out the polymers. Examples 2 to 7 were obtained by dissolving these polymers in dimethylformamide and spinning them.

On the other hand, in Comparative Examples 3 to 8, tin dichloride was not added to the polymerization reaction mixture, but various amounts of metastannic acid were added to the spinning stock solution.
and spun. The results are shown in Table 2.

Table 2 The fibers of Examples 2 to 7 contain tin oxychloride (JV) and are glossy.

While both transparency and flame retardancy are good, in comparison examples made using the conventional flame retardant strengthening method, flame retardance improves as the amount of metastannic acid is increased, but gloss and transparency decrease. On the contrary, it decreases, making it difficult to obtain the desired quality. Comparing the Examples and Comparative Examples, it can be seen that the present invention is clearly superior.

Examples 8 to 10, Comparative Example 9 In the spinning dope of Comparative Example 1, the tin compound in the fiber was also added to L- (so that the tin compound was 0.7% in terms of metal tin or metal tin content). , and other additives were mixed and spun.The results are shown in Table 3.

Table 3 As shown in Table 3, Examples 8 to 1O of the present invention had the desired quality, whereas Comparative Example 9 obtained a relatively good evaluation from the results in Table 3. The fibers are used to make woven fabrics, such as J' I S L1091-1978 A
When subjected to a flammability test such as the -1 method, the fiber failed due to the afterflame time, so it cannot be said to be a practical fiber.

patent applicant Kanebuchi Chemical Industry Co., Ltd.

Claims (1)

[Scope of Claims] ■, Acrylic comprising a polymer composed of IJ and a vinyl monomer copolymerizable therewith, and containing a halogen-containing inorganic tin compound. synthetic fiber. 2. The polymer is 30 to 70% by weight of acrylonitrile,
Acrylic synthesis according to claim 1, which is a copolymer composed of 70 to 30% by weight of a halogen-containing vinyl monomer and 0 to IO% by weight of a vinyl monomer copolymerizable therewith. fiber. 3. The acrylic synthetic fiber according to claim 2, wherein at least one of the copolymerizable vinyl monomers is a sulfonic acid group-containing vinyl monomer.