JPS62125849A - Hexaantimony tridecaoxide aqueous sol - Google Patents

Abstract

PURPOSE:To obtain the titled aq. sol contg. extremely fine hexaantimony tridecaoxide(Sb6O13) and having excellent chemical stability by dispersing the Sb6O13 having specified particle diameter in an aq. medium. CONSTITUTION:Antimony trioxide, hydrogen peroxide, and a specified alkali metal compd. are mixed in a specified molar ratio, the aq. dispersion is heated, and the Sb6O13 particles having 1-100mmu particle diameter are dispersed in the aq. medium. The Sb6O13 aq. sol has a high concn., a low content of impurities, and excellent thermal stability and chemical stability. The sol, when mixed into a fiber-forming spinning soln., is not condensed, and no frothing is caused due to thermal decomposition even in metal spinning.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an aqueous sol of hexaantimony dexaoxide having a fine particle size and excellent stability.

(Prior art) Antimony oxide has traditionally been used in combination with organic chlorides, bromides,
It was used as a flame retardant synergist to improve the flame retardant effect together with other flame retardants such as halogen-containing substances. However, conventional antimony oxide is a large particle with a particle size comparable to that of a pigment, so the texture of products using it
There was a drawback that gloss, transparency, and other physical properties were deteriorated. In order to overcome these drawbacks, research has been conducted in recent years on methods for obtaining fine particulate antimony oxide. A method for producing an antimony pentoxide (sb70.) colloidal sol having a particle size of 2 to 100 mμ by reacting it to form potassium antimonate and then deionizing it.
Japanese Patent Publication No. 57-11848), and a method for producing an aqueous antimony pentoxide colloidal sol by refluxing a mixture of antimony trioxide, hydrogen peroxide, and water for 1 to 10 hours and then cooling it (Japanese Patent Publication No. 52-198) 123997) is known.

On the other hand, the above-mentioned antimony pentoxide decomposes upon heating and releases oxygen, and at 780 to 920°C, antimony hexaoxide (
S b60. ,, hereinafter referred to as antimony 13 oxide), and as the temperature rises further, antimony tetroxide (Sb,
04) has been known for a long time to be produced (Inorganic Aji 71V-4, Maruzen Co., Ltd., May 1950 250
Publication, pp. 168-170).

(Problems to be Solved by the Invention) In the production of the colloidal sol of antimony pentoxide in the former known method (Japanese Patent Publication No. 57-11848), a large amount of hydroxide columnum is used. Potassium remains and requires a deionization step to remove this impurity. In addition, in this known production method, when the concentration is high, the particle size becomes large, so it is necessary to reduce the concentration of antimony pentoxide in the colloidal sol.
In order to obtain a product with a high enough concentration to have commercial value, an additional evaporation step is required, which increases the number of manufacturing steps and is cumbersome. The latter method (Japanese Unexamined Patent Publication No. 52-123997) does not add an alkaline substance, so there is no problem in removing impurities, but on the other hand, the reaction speed is very slow, so it is necessary to carry out the reaction at a high temperature close to boiling. There are risks such as bumping during the reaction, and once one reaction has started, the temperature rapidly rises due to the reaction heat, making it difficult to control the temperature.Not only is it impossible to increase the production scale, but equipment is also limited. It also has to be expensive in terms of energy. Furthermore, as mentioned above, antimony pentoxide thermally decomposes at a relatively low temperature, so its thermal stability is not sufficient, and the foaming caused by the release of oxygen during melt molding of plastics deteriorates the physical properties of the molded product and reduces its appearance. There are problems such as damage to the In addition, when antimony pentoxide colloidal sol is mixed with one type of latex and used, it aggregates due to inorganic salts in the latex, and there is a problem that it lacks so-called chemical stability.

On the other hand, antimony 13 oxide is produced as an intermediate oxide when antimony pentoxide is heated to produce antimony tetroxide as described in the above-mentioned document. During the manufacturing process, especially during the drying process, the primary particles aggregate and become larger, and even if they are crushed, the I! 11Np'1. Only particles with a large particle size can be obtained.

Therefore, an aqueous sol containing sb, o, and 3 particles of fine particle size has not yet been known.

Previously, the present inventors proposed an improved method for producing the above-mentioned known antimony pentoxide colloidal sol by mixing antimony trioxide, hydrogen peroxide, and an inorganic alkaline substance in a ratio of 1:1.25 or more:
'XI production method of colloidal antimony oxide mixed and reacted at a molar ratio of 0.015 to 0.3 (JP-A-59-23
29] Japanese Patent Publication No. 137828/1982)
invented. As a result of subsequent research, the colloidal antimony oxide obtained by setting the molar ratio of hydrogen peroxide within a specific range and selecting a specific inorganic alkaline substance in the above invention was found to be more effective than antimony decaoxide. It is an aqueous sol, and they learned that this aqueous sol has excellent chemical stability.

(Means for Solving the Problems) The present invention is an aqueous sol of hexaantimony decaoxide, characterized in that hexaantimony decathoxide particles having a particle size of 1 to 100 mμ are dispersed in an aqueous medium. The aqueous sol of this invention contains antimony trioxide, hydrogen peroxide,
It is obtained by heating an aqueous dispersion in which a specific alkali metal compound is mixed in a specific molar ratio.

The particle size of the antimony decathoxide in the aqueous sol of this invention is extremely fine particles with a diameter of 1 to 100 mμ, preferably 1 to 50 mμ. This particle diameter is a value obtained by photographing at a magnification of 1,000,000 times using an electron microscope (model IAH-800 manufactured by Hitachi, Ltd.).

Antimony oxide in aqueous sol is also described in Canadian Journal of Chemistry, Vol. 50 (1972).
It was identified as antimony decaoxide based on the X-ray diffraction pattern shown in FIG. 2(e) described on page 696.

The antimony 13 oxide aqueous sol of this invention has a pH of 1.
It maintains a stable aqueous sol state without agglomeration in the range of 0 to 10.0, particularly 1.5 to 8.0, and has excellent chemical stability. This chemical stability is judged by the change in light transmittance of the aqueous sol. The light transmittance is tlITAclllI-1015pect;roph
.

The value is the light transmittance of white light measured for a colloidal sol with a solid content concentration of 0.4% using a tomet, er (newly manufactured by Hitachi). The light transmittance after 5 minutes of a mixed solution in which an aqueous solution (Pold 4) was added and stirred is shown. The larger the value of this light transmittance, the smaller the particles and the less agglomerated they are.

The aqueous medium in the aqueous sol is water alone, or an aqueous mixed solvent of water and a water-miscible organic medium such as methyl alcohol, ethyl alcohol, propyl alcohol, or acetone within a range that does not impair the stability of the aqueous sol.

To produce the aqueous sol of this invention, antimony trioxide, hydrogen peroxide, and a specific alkali metal compound are
: 1:1.8: React at a ratio of 0.015 to 0.3 mol.

The particle size of antimony trioxide is 100μ or less, but from the point of view of dispersibility in water and reactivity with hydrogen peroxide, it is 0.5μ in diameter.
It is preferable that it is 1-10 micrometers. In order to prepare a dispersion liquid by dispersing this antimony trioxide in an aqueous medium, the concentration of antimony trioxide in the dispersion liquid is 5 to 40 weight-1 it%.
, preferably 7 to 25% by R amount.

The blending amount of hydrogen peroxide is 1:1.8 mol per 1 mol of antimony trioxide; if it is less than 1.25 mol, colloidal fine particles cannot be obtained, and on the other hand, if it exceeds 1.8 mol, Chemical stability against electrolytes such as inorganic salts decreases, and unreacted hydrogen peroxide remains in the resulting aqueous sol, which is undesirable.

The alkali metal compound blended into the antimony trioxide dispersion is selected from lithium hydroxide, monohelium hydroxide, lithium carbonate, and sodium carbonate. When other alkali metal compounds such as potassium hydroxide and calcium hydroxide are used, fine particulate antimony hexoxide will not be produced. The amount of the above specific alkali metal compound is 0.0 per mole of antimony trioxide.
The amount is 15 to 0.3 mol, preferably 0.02 to 0.2 mol. If the amount of the alkali metal compound is less than 0.015 mol, the reaction will be slow, so it is necessary to maintain the reaction temperature near or above the boiling point of water. The particle size of antimony increases. On the other hand, if the amount of the alkali metal compound exceeds 0.3 mol, fine particulate antimony decathoxide cannot be selectively produced, and in a high-concentration reaction system, the proofreading and diameter become extremely coarse.

There is no particular restriction on the order in which the above-mentioned raw materials antimony trioxide, hydrogen peroxide, and alkali metal compound are blended; for example, they may be mixed together at the same time to form an aqueous dispersion, or an aqueous dispersion of antimony trioxide and an alkali metal compound may be mixed together. Hydrogen peroxide may be mixed with the liquid.

The temperature for reacting the aqueous dispersion is 30°C or higher, preferably 50-100°C, but the reaction can be started even at a low temperature of 5°C or lower, reducing the energy required to heat the reaction system. Not only is this reduced, but most of the exothermic heat produced by the reaction is absorbed as the amount of heat necessary to raise the temperature of the reaction system to the boiling point, so there is little need for external cooling, and there is no need to adjust the temperature to prevent bumping. There isn't.

The solid content concentration in the aqueous sol obtained by the above reaction is 6 to 4 depending on the concentration of antimony trioxide in the aqueous dispersion.
5% by weight, preferably from 8 to 28% by weight, but optionally without the addition of stabilizers by concentrating the aqueous sol.

It can be an aqueous sol with a solid content concentration of 45% by weight or more.

In addition, the above aqueous sol requires 2 yen to adjust the pH.
Soft alkaline compounds can be added.

(Function) Although the mechanism by which an extremely fine and chemically stable antimony trioxide aqueous sol is obtained in this invention is not clear, a specific alkaline earth compound acts as a catalyst in the reaction between antimony trioxide and hydrogen peroxide. It is presumed that antimony decaoxide is selectively formed and refined by the specific amount of the alkali metal compound.

Example 1 A three-loaf flask (capacity 11Q) with a stirrer was immersed in a constant temperature water bath at 90°C, and 5b2o of water was added to the flask.

(a degree 13% by weight, average particle size 0.8μ) and Na0
11 aqueous solution (concentration 25% by weight) and when the temperature of the contents reaches 50°C, add hydrogen peroxide aqueous solution (35% by weight).
% by weight) was added and reacted for 1 hour.

The blending ratio of the dispersion, the particle diameter of antimony decathoxide, the light transmittance, and the chemical stability (light transmittance at 5% sodium chloride level) of the aqueous sol are shown in Table 1 below.

(Blank below) As shown in Table 1 above, which experiment N of Example 1
As for α, the particle size of antimony dexoxide is extremely small and has excellent chemical stability, but the comparative example 820 and the experimental Na 6 with a small ratio have large particle sizes and poor chemical stability.
Experiment Nα7 with a large H2O2 molar ratio has a small particle size but poor chemical stability, and experiment N with no NaOH added.
Experimental corner 9, which had a large amount of α8 and Na○■, both had significantly large particle diameters.

In addition, commercially available antimony pentoxide aqueous sol (Nyaco1
Co., Ltd., concentration 50% by weight) had a particle diameter of 20 to 50 mμ, but its chemical stability was 10% or less.

Example 2 The fruit of Example 1 above! 91NQ3. and Comparative Example Experiment N
Table 2 below shows the results when the concentration of antimony trioxide was varied in α9.

As is clear from Table 2 above, even if the sb, o, and 'a degrees are increased, the particle size is small and the chemical stability is excellent.

Usage Examples 1-0 The antimony decathoxide aqueous sol obtained in Experiment 3 of Example 1 was mixed with 2.7% acrylonitrile, 9% vinylidene chloride (electrophasic component), and 8% methyl acrylate. and 0.3% by weight of sodium methallylsulfonate into a 50% aqueous solution of rhodan soda (polymer concentration 10% by weight, pH 5, 6). Solid content of antimony decathoxide based on the weight of the copolymer. is 5
%, and mixed and stirred using a pipeline homo mixer (manufactured by Tokushu Kikako Co., Ltd.) to produce an acrylic spinning dope in which antimony decathoxide fine particles were uniformly dispersed. This spinning stock solution was spun into a 13% Rodan soda aqueous solution at -3°C, and then washed with water, stretched, dried, and
A 10 denier acrylic fiber was obtained by heat treatment.

The knit L○■ value of the obtained fiber was 211.5, and there was no devitrification and the dyeing clarity was also good. As a comparative example, the knit LOI value of a 10-denier fiber obtained in the same manner as above using a spinning dope without adding an aqueous sol of antimony trioxide was 21.0. The nit LOI value without addition was 18.0, which indicates that the antimony decaoxide aqueous sol of the present invention has a synergistic effect on the antimony. The above knit LOI value is calculated using the above 10 denier fiber and made into a 1/IO's yarn using a conventional method, and has a basis weight of 300 g/rr? Knitting Amagasa knitted fabric, J
The value is determined according to IS-7201, and the larger the value, the greater the flame retardant effect.

(Effects of the invention) The effects of this invention are that it is a previously unknown aqueous sol of antimony decathoxide with fine particles, which is highly concentrated, has few impurities, and is thermally and chemically stable. The reason is that we have provided

In other words, the aqueous sol of the present invention is stable without condensation when mixed with a spinning stock solution for fiber forming, etc., and does not cause foaming due to thermal decomposition during melt spinning, and does not cause problems such as deterioration of physical properties and appearance during operation. problem is solved. Furthermore, the aqueous antimony 13 oxide sol of the present invention can be used as an aqueous sol as in the above usage example, or if desired, it can be further concentrated or spray-dried to form antimony 13 oxide particles, such as a flame retardant synergist, etc. It can be used for various purposes.

7 Contents of the amendment Procedures Amendment band December 24, 1985 Patent Application No. 266866 of 1985 2 Name of the invention Antimony trioxide aqueous sol 3 Relationship with the case of the person making the amendment Patent applicant's residence Location Kita, Osaka City Ward Dojimahama 2-2-8 Name (40
5) Nippon Exlan Kogyo Co., Ltd. 4 Agent Residence: 2-10 Azuchi-cho, Higashi-ku, Osaka City Residence: Same as above.
Part 6: Subject of amendment (1) On page 2 of the specification cylinder, line 5, "It was used." was corrected to "It was used and worked."

(2) Specifications section, page 7, line 8 "rNaCL aqueous solution" was corrected to "Wenzaku aqueous solution".

(3) On page 13 of the specification, line 4 from the bottom, "acrylonitrile 2.7" was corrected to "acrylonitrile U2".

(/I) All page 14, line 16, ``Not added'' was corrected to ``Not added, and the acrylonitrile was 91.7% by weight.''

(5) Mei A+ Book, page 14, line 19 “It shows” was corrected to “It shows.”

Claims (1)

[Scope of Claims] [1] An aqueous sol of hexaantimony dexaoxide, characterized in that hexaantimony dexaoxide particles having a particle size of 1 to 100 mμ are dispersed in an aqueous medium. [2] Antimony trioxide, hydrogen peroxide, and an alkali metal compound selected from lithium hydroxide, sodium hydroxide, lithium carbonate, and sodium carbonate in a ratio of 1:1.25 to
The aqueous sol of hexaantimony decathoxide according to claim 1 obtained by heating an aqueous dispersion mixed at a molar ratio of 1.8:0.015 to 0.30.