JPH09100121A - Production of double metal hydroxide, double metal hydroxide obtained by the same production method and flame-retardant polymer composition using the same hydroxide - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a double metal hydroxide as a uniform metal solid solution, excellent in flame retardance, by specifying a production method in a double metal hydroxide of zinc and magnesium. SOLUTION: A magnesium-containing aqueous solution X containing a water- soluble zinc compound and having 0.01-1mol/liter magnesium ion concentration is reacted with an alkali substance Y in a reaction equivalent ratio (X:Y) of X:Y=1:1.01 to 1.20. The formed double metal hydroxide is subjected to hydrothermal treatment in a chlorine-containing aqueous solvent having 0.5-2.0mol/liter chloride ion concentration at 100-200 deg.C. Consequently, the objective double metal hydroxide of the formula Mg1-x Znx (OH)2 [(x) is 0.003<=x<=0.1] is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a composite metal hydroxide which is a uniform solid solution, a composite metal hydroxide obtained thereby, and flame retardance and mechanical properties obtained using them. The present invention relates to a flame-retardant polymer composition having excellent strength.

[0002]

2. Description of the Related Art Demands for flame retardancy of resin compositions or rubber compositions have become stricter year by year due to serious fire accidents that occurred in the past.

In order to meet such a demand for flame retardancy, various flame retardants are currently on the market. Among them, from the viewpoint of safety in production and use, demands for strict flame retardancy have been strengthened centering on non-halogen flame retardants, and metal hydroxides have been receiving attention.

[0004]

However, among the above metal hydroxides, for example, aluminum hydroxide is
Since the dehydration temperature is low (about 190 ° C.), the temperature at the time of molding must be maintained below this dehydration temperature, and there is a problem that the types of applicable resins are limited. Also,
Since magnesium hydroxide has a dehydration initiation temperature of about 340 ° C, there is almost no restriction on the type of resin that can be applied, but in order to obtain flame retardancy, a large amount of magnesium hydroxide must be blended. There are many practical problems in that the physical properties of the resin are deteriorated due to the filling property. In order to solve these problems, for example, JP-A-6-4144
In Japanese Patent Publication No. 1, a composite metal hydroxide is proposed. Compared with magnesium hydroxide, these complex metal hydroxides can exhibit a flame-retardant effect with a low compounding amount. However, regarding the mixed metal hydroxide of zinc and magnesium hydroxide, due to the nature of zinc, which is a solid solution element, in the conventional manufacturing method, basic salts and oxides (zinc oxide) are by-produced as by-products. However, it is difficult to obtain a composite metal hydroxide that is a uniform solid solution, and it is difficult to achieve expected properties (flame retardancy, mechanical strength, etc.).

The present invention has been made in view of such circumstances, and a method for producing a composite metal hydroxide which is a uniform metal solid solution having excellent flame retardancy, a composite metal hydroxide, and a machine. It is an object of the present invention to provide a flame-retardant polymer composition having excellent dynamic strength.

[0006]

To achieve the above object, the present invention provides a magnesium-containing aqueous solution (X) containing a water-soluble zinc compound and having a magnesium ion concentration of 0.01 to 1 mol / liter. , Alkaline substances (Y)
In the reaction equivalent ratio (X: Y), X: Y = 1: 1.01
The first aspect is a method for producing a composite metal hydroxide to be reacted at 1: 1.20, and in this production method, the produced composite metal hydroxide is added with a chloride ion concentration of 0.5 to 2.0 mol / liter. The second method for producing a composite metal hydroxide is hydrothermal treatment in a chlorine-containing aqueous medium within a temperature range of 100 to 200 ° C.
In addition, in this production method, the produced composite metal hydroxide is added in the presence of a reaction mother liquor at 80 to 150 ° C.
The third gist is a method for producing a composite metal hydroxide in which only the crystal surface portion of the composite metal hydroxide is replaced with nickel by heating within the temperature range of 10 and adding a water-soluble nickel compound solution. .

Then, the following formula (1) obtained by the method for producing the composite metal hydroxide, which is the first or second aspect of the present invention, is obtained.
The fourth gist is a composite metal hydroxide represented by.

Embedded image Mg _1-x Zn _x (OH) ₂ (1) [In the formula (1), x is a positive number of 0.003 ≦ x ≦ 0.1. ]

A fifth aspect is a complex metal hydroxide represented by the following formula (2) obtained by the method for producing a complex metal hydroxide which is the third aspect.

_{Embedded image} Mg _1-xy Zn _x Ni _y (OH) ₂ (2) [In the formula (2), x is a positive number of 0.003 ≦ x ≦ 0.1, y
Is a positive number of 0.01 ≦ y ≦ 0.05. ]

Further, 80 to 150 parts by weight of the composite metal hydroxide represented by the above formula (1) or the composite metal hydroxide represented by the above formula (2) is added to 100 parts by weight of the polymer compound. The flame-retardant polymer composition contained within the range of the sixth
The summary of the

That is, since the stable crystal form of the hydroxide is not a hexagonal crystal, it is difficult for the present inventors to stably produce a composite metal hydroxide which is a uniform solid solution with Mg by the conventional manufacturing method. Therefore, a series of studies were conducted on the reaction process for obtaining a uniform solid solution. Then, first, attention was paid to the Mg ion concentration of the Zn-containing Mg aqueous solution serving as the Mg source and the reaction equivalence ratio between the Zn-containing Mg aqueous solution and the alkaline substance, and further research was conducted focusing on these two points. As a result, the Mg ion concentration is 0.01 to 1
Using a Zn-containing Mg aqueous solution set to mol / liter,
In addition, the reaction equivalent ratio (X: Y) of the Zn-containing Mg aqueous solution (X) and the alkaline substance (Y) is X: Y = 1: 1.
It was found out that the composite metal hydroxide represented by the above formula (1), which is a uniform solid solution, can be obtained by reacting both by setting it to 01 to 1: 1.20. Furthermore, the composite metal hydroxide obtained by reacting at the above reaction equivalence ratio is added to 100 to 2 in an aqueous medium having a specific chloride ion concentration.
The inventors have also found that it becomes possible to control the crystal shape of the composite metal hydroxide produced by hydrothermal treatment and aging in the temperature range of 00 ° C., and to suppress the occurrence of secondary aggregation.

Then, the obtained composite metal hydroxide is heated in the temperature range of 80 to 150 ° C. in the presence of the reaction mother liquor, and a water-soluble Ni compound solution is added to the crystal surface portion. The present invention has been accomplished by finding that a composite metal hydroxide represented by the above formula (2), in which only Ni is substituted, is obtained.

Then, 80 to 150 parts by weight of the composite metal hydroxide represented by the above formula (1) and the composite metal hydroxide represented by the above formula (2) are added to 100 parts by weight of the polymer compound. The flame-retardant polymer composition obtained by containing it within the range has high flame retardancy while having a lower content than before, and is sufficiently satisfactory in mechanical strength (tensile strength, etc.). I found that

[0013]

Next, the present invention will be described in detail.

The method for producing the composite metal hydroxide of the present invention mainly comprises three steps.

That is, by using a Zn-containing Mg aqueous solution having a specific Mg ion concentration and reacting the Zn-containing Mg aqueous solution with an alkaline substance at a specific equivalent ratio, the following formula (1) is obtained. The first step is the reaction process for producing the mixed metal hydroxide. It is preferable that the reaction step of the first stage is performed at a temperature in the range of 10 to 35 ° C.

[0016]

[Image Omitted] Mg _1-x Zn _x (OH) ₂ (1) [In the formula (1), x is a positive number of 0.003 ≦ x ≦ 0.1. ]

In the above formula (1), the value of x is 0.00
When it is less than 3, the amount of solid solution is insufficient to develop the expected effect of the composite metal hydroxide (high flame retardancy). Also,
When it exceeds 0.1, since the ionic radius of zinc is larger than that of magnesium, it becomes difficult to form a uniform solid solution, and by-products of basic salts and oxides are confirmed. Further, it becomes difficult to control the crystal shape, secondary aggregation easily occurs, and the expected effect of the composite metal hydroxide does not appear.

Examples of the above-mentioned Zn-containing Mg aqueous solution include a Zn aqueous solution added with a Zn compound. M above
Examples of the g aqueous solution source include diluted bittern, seawater, magnesium nitrate and the like, and the Mg ion concentration thereof is 0.01 to 1
It should be set in the range of mol / liter. It is preferably in the range of 0.03 to 0.3 mol / liter. That is, for example, when dilute bitter juice or seawater is used as the Mg aqueous solution source, if the Mg ion concentration exceeds 1 mol / liter, the by-product of the basic salt becomes predominant and it is difficult to form a uniform solid solution. It is because The measurement of the Mg ion concentration is not particularly limited as long as it is a method for generally analyzing the ion concentration in the solution, such as a chelate titration method or ICP emission spectroscopy.

The Zn compound added to the Mg aqueous solution is not particularly limited as long as it is a water-soluble zinc compound such as zinc nitrate and zinc chloride. And that M
The amount of Zn added to the aqueous solution is preferably set so that Zn is in the range of 0.3 to 10 mol% with respect to Mg in the aqueous solution, and particularly preferably 1 to 7 mol%. That is, if the addition amount is less than 0.3 mol%, the amount of solid solution is insufficient to develop the expected effect (high flame retardancy) of the composite metal hydroxide. On the contrary, if it exceeds 10 mol%, since the ionic radius of zinc is larger than that of magnesium, it becomes difficult to form a uniform solid solution, so that by-products of basic salts and oxides are confirmed. Become. Further, it is difficult to control the crystal shape, and secondary aggregation is likely to occur, and the expected effect of the composite metal hydroxide tends not to be exhibited.

The alkaline substance to be reacted with the Zn-containing Mg aqueous solution having the above specific Mg ion concentration includes calcium hydroxide, sodium hydroxide and the like.

Then, in the first step, the above M containing Zn is
g The reaction ratio between the aqueous solution (X) and the alkaline substance (Y) is equivalent ratio (X: Y), and X: Y = 1: 1.01-1:
It should be set to 1.20. Particularly preferably, X:
Y = 1: 1.03 to 1: 1.10. That is, in the above reaction equivalence ratio, the alkaline substance (Y) is 1.0
If it is less than 1, a basic salt by-product is recognized and a uniform solid solution cannot be formed, and conversely, the alkaline substance (Y) is not formed.
When it exceeds 1.20, by-products of oxides are recognized,
This is because it becomes difficult to control the crystal shape and secondary aggregation easily occurs.

A preferable combination of the Zn-containing Mg aqueous solution and the alkaline substance used in the first step is as follows.
From the viewpoint of stability and production cost of the produced mixed metal hydroxide, seawater (Mg aqueous solution) obtained by adding zinc chloride, which is a water-soluble zinc compound, to an aqueous Mg solution containing Zn and calcium hydroxide (lime milk) as an alkaline substance. ) Is a combination that uses.

Next, a description will be given of a second-stage manufacturing method which is performed subsequent to the above-mentioned first-stage manufacturing method of the composite metal hydroxide.

In the second step, the composite metal hydroxide represented by the formula (1) produced by the reaction step in the first step is used in a chlorine-containing aqueous medium having a specific chlorine ion concentration. And a hydrothermal treatment in a temperature range of 100 to 200 ° C. for aging.

Examples of the chlorine-containing aqueous medium include calcium chloride aqueous solution, sodium chloride aqueous solution, magnesium chloride aqueous solution, potassium chloride aqueous solution and the like. Above all, it is preferable to use an aqueous solution of calcium chloride as the chlorine-containing aqueous medium from the viewpoint of controlling the crystal shape of the composite metal hydroxide. And the chlorine ion concentration in these chlorine-containing aqueous media must be in the range of 0.5 to 2 mol / liter. Particularly preferably 0.5-1.
It is 0 mol / liter. That is, when the chlorine ion concentration is as low as less than 0.5 mol / liter, the control of the crystal shape of the composite metal hydroxide becomes insufficient, and secondary aggregation easily occurs. On the other hand, when it exceeds 2 mol / liter, by-products of basic salts and oxides are recognized, and it becomes difficult to form a uniform solid solution. The measurement of the chlorine ion concentration is not particularly limited as long as it is a method for generally analyzing the ion concentration in the solution, such as a chelate titration method or ICP emission spectroscopy.

Further, as the aging condition by the hydrothermal treatment, the temperature must be within the range of 100 to 200 ° C., and accordingly, the pressure is usually 0.5 to 10 kg / cm.
It becomes ² .

The composite metal hydroxide thus obtained is represented by the above formula (1), and the crystal is further grown by passing through the step of the second step, and Secondary aggregation will be reduced, compatibility with the polymer compound described below, dispersibility, appearance of the molded article,
Considering various characteristics such as mechanical strength, it is an even more preferable flame retardant.

Next, a description will be given of the third step of producing the composite metal hydroxide in the second step. The composite metal hydroxide obtained by this production method is
A composite metal hydroxide represented by the following formula (2):
It is a solid solution of three metal elements of Mg, Zn and Ni.

[0029]

_{Embedded image} Mg _1-xy Zn _x Ni _y (OH) ₂ (2) [In the formula (2), x is a positive number of 0.003 ≦ x ≦ 0.1, y
Is a positive number of 0.01 ≦ y ≦ 0.05. ]

In the above equation (2), the value of x is 0.00
When it is less than 3, the amount of solid solution is insufficient to develop the expected effect of the composite metal hydroxide (high flame retardancy). vice versa,
When it exceeds 0.1, since the ionic radius of zinc is larger than that of magnesium, it becomes difficult to form a uniform solid solution, and by-products of basic salts and oxides are confirmed. Further, it becomes difficult to control the crystal shape, secondary aggregation easily occurs, and the expected effect of the composite metal hydroxide does not appear. On the other hand, if the value of y is less than 0.01, the amount of nickel substitution on the crystal surface portion will be insufficient, and the expected effect of the composite metal hydroxide cannot be sufficiently exhibited. Further, even if the amount added exceeds 0.05, only the cost is increased, and the nickel substitution amount on the crystal surface portion is saturated, which causes a problem such as by-product of free nickel hydroxide.

In the third step, the composite metal hydroxide represented by the formula (1) produced by the reaction step in the second step is used, and this is used in the presence of the reaction mother liquor at 80 to 150 ° C.
By heating in the temperature range of 1, and adding a water-soluble nickel compound solution to this to replace only the crystal surface portion with Ni to form a composite metal hydroxide represented by the above formula (2). It is a process.

The above water-soluble nickel compound solution is
Examples thereof include a nickel chloride aqueous solution and a nickel nitrate aqueous solution. Of these, nickel chloride is preferably used from the viewpoint of reactivity with the composite metal hydroxide. The addition ratio of the water-soluble nickel compound solution is 1 to the mixed metal hydroxide in the reaction mother liquor to be added.
It is preferably set in the range of 5 mol%. It is particularly preferably 1 to 3 mol%.

Further, as the temperature condition when the water-soluble nickel compound solution is added, as described above, the temperature must be heated in the range of 80 to 150 ° C. Particularly preferable temperature condition is 9
0-120 ° C. By setting such a temperature range, it becomes possible to effectively replace only the crystal surface portion with nickel. That is, if the set temperature is too low, substitution is insufficient and free nickel hydroxide by-products are generated,
On the other hand, if the set temperature is too high, nickel substitution will proceed to the inside of the crystal, and the expected effect will not be obtained in any case.

In this way, the above formula (1) obtained through the manufacturing process up to the first stage or the second stage
The complex metal hydroxide represented by the formula (1) or the complex metal hydroxide represented by the formula (2) obtained through the manufacturing steps up to the third stage has a crystallite size of 0. 2 to
4 μm, more preferably 0.2 to 2 μm, particularly preferably 0.5 to 1.5 μm, with little or little secondary aggregation, that is, an average secondary particle diameter of 0.2 to
4 μm, more preferably 0.2 to 2 μm, particularly preferably 0.5 to 1.5 μm, and a BET specific surface area of 1 to ²⁰ m ² / g, more preferably 3 to 15 m ² / g,
Particularly preferably, it is 6 to 12 m ² / g. That is, the above-mentioned composite metal hydroxide has such a range of characteristic values, so that the compatibility, dispersibility, moldability, appearance of the molded product, and mechanical properties with polymer compounds such as resins and rubbers described later are obtained. It is possible to maintain excellent effects in various properties such as strength. The average secondary particle size is
It is a value measured by the Microtrack method after ultrasonically dispersing the sample powder in a 0.2% sodium hexametaphosphate aqueous solution.

The BET specific surface area is a value measured according to the N ₂ adsorption method.

The thus obtained composite metal hydroxides represented by the above formulas (1) and (2) can be used as they are as flame retardants, but further, various fatty acids and phosphoric acid esters are used. Alternatively, those surface-treated with a surface-treating agent such as a coupling agent may be used. The above various surface treatment agents may be used alone or in combination of two or more.

Examples of the above various fatty acids include higher fatty acids having 10 or more carbon atoms such as oleic acid, stearic acid, erucic acid, palmitic acid, lauric acid and behenic acid, and alkali metal salts of these higher fatty acids. Also,
Examples of the phosphoric acid ester include orthophosphoric acid and mono- or diesters of oleyl alcohol, stearyl alcohol, etc., or a mixture of both, acid-type or alkali metal salts thereof, amine salts and the like.

As the above coupling agent, vinylethoxysilane, vinyl-tris (2-methoxy-ethoxy) silane, γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, β-
Silane coupling agents such as (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, isopropyltriisostearoyl titanate, isopropyltris (dioctylpyrophosphate) Examples thereof include titanate-based coupling agents such as titanate, isopropyltri (N-aminoethyl-aminoethyl) titanate, and isopropyltridecylbenzenesulfonyl titanate, and aluminum-based coupling agents such as acetoalkoxyaluminum diisopropylate.

The surface treatment of the composite metal hydroxide using the above-mentioned various surface treatment agents is not particularly limited and may be carried out by a conventionally known wet or dry method.

By adding the composite metal hydroxide represented by the formula (1) and the composite metal hydroxide represented by the formula (2) to the polymer compound as a flame retardant, high flame retardancy can be obtained. A molecular composition is obtained.

The polymer compound is not particularly limited, and examples thereof include general resins and rubbers. For example, polyethylene, copolymers of ethylene and other α-olefins, copolymers of ethylene and vinyl acetate, ethyl acrylate or methyl acrylate, polypropylene, copolymers of propylene and other α-olefins, polybutene. -1, polystyrene, copolymer of styrene and acrylonitrile, thermoplastic resin such as vinyl acetate, polyacrylate, polymethacrylate, polyurethane, polyester, polyether, polyamide, phenol resin, melamine resin, epoxy resin, unsaturated polyester resin , Thermosetting resins such as alkyd resins, ethylene-propylene-diene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, butyl rubber,
Examples include isoprene rubber and chlorosulfonated polyethylene. These polymer compounds are appropriately selected depending on the application and the like.

The compounding amounts of the composite metal hydroxide represented by the formula (1) and the composite metal hydroxide represented by the formula (2) are appropriately selected depending on the kind of the polymer compound. Is a polymer compound 100 parts by weight (hereinafter abbreviated as “part”)
Is set in the range of 80 to 150 copies. It is particularly preferably 100 to 130 parts. That is, if the compounding amount of the composite metal hydroxide is less than 80 parts, the flame retardancy becomes insufficient, and conversely, if the compounding amount exceeds 150 parts, the mechanical properties such as tensile strength decrease. . Then, the composite metal hydroxides represented by the formulas (1) and (2) may be used alone within the range of the above blending amount,
You may use together.

The flame-retardant polymer composition of the present invention obtained by blending a composite metal hydroxide with a polymer compound,
In addition to the composite metal hydroxide represented by the formula (1) and the composite metal hydroxide represented by the formula (2), various additives may be added as necessary. Examples include common flame retardant aids such as carbon fine powder and red phosphorus. Further, a lubricant, an antioxidant, an anti-UV agent, an antistatic agent, a pigment, a foaming agent, a plasticizer, a filler, a reinforcing agent, a cross-linking agent and the like can be mentioned.

The flame-retardant polymer composition of the present invention comprises a polymer compound containing a predetermined amount of a composite metal hydroxide represented by the formula (1) and a composite metal hydroxide represented by the formula (2). It is obtained by blending, mixing and kneading. The above mixing and kneading methods are not particularly limited and conventionally known methods,
For example, a mixing and kneading method using a single-screw or twin-screw extruder, a roll, a Banbury mixer and the like can be mentioned.

Further, the molding method using the flame-retardant polymer composition thus obtained is not particularly limited, and it depends on the kind of polymer compound, the kind of desired molded article and the like. Then, a molding method using an appropriate molding means can be mentioned. For example, injection molding, extrusion molding, blow molding, press molding, rotational molding, calendar molding, sheet forming molding, transfer molding, lamination molding, vacuum molding and the like can be mentioned.

Next, examples will be described together with comparative examples.

[0047]

Example 1 First-grade zinc chloride as a reagent was dissolved in ionic bitterness and diluted with ion-exchanged water to obtain a Mg ion concentration of 0.14.
300 liters of a mixed aqueous solution having a mol / liter and a Zn ion concentration of 0.008 mol / liter was prepared. Also, as the alkaline substance, 0.9 mol / liter of lime milk 5
1 liter was produced, and both were continuously added with stirring in a continuous reaction tank having an effective volume of 50 liters with stirring so that the mixed aqueous solution: lime milk = 1: 1.03 at a reaction equivalence ratio. Further, this reaction product was emulsified in an aqueous calcium chloride solution having a chlorine ion concentration of 1.0 mol / liter to obtain a volume of 1
Place in a 00 liter autoclave with stirrer,
It was hydrothermally treated at ℃ for 2 hours. After that, filtration with a filter press, washing with water, dehydration, drying in an oven and pulverization were carried out to obtain the target composite metal hydroxide.

[0048]

Example 2 In Example 1, emulsification of the reaction product was carried out with an aqueous sodium chloride solution having a chloride ion concentration of 0.5 mol / liter, and hydrothermal reaction was carried out at 170 ° C. for 2 hours.
Other than that was obtained in the same manner as in Example 1 to obtain a target composite metal hydroxide.

[0049]

[Example 3] 50 liters of a mixed aqueous solution obtained by dissolving first-grade reagent zinc nitrate in ionic bitter juice and diluting with ion-exchanged water and having a Mg ion concentration of 1.0 mol / liter and a Zn ion concentration of 0.003 mol / liter Was produced. Further, 52 liters of 1.0 mol / liter lime milk was prepared as an alkaline substance, and a continuous system with an effective volume of 10 liters was prepared so that both were in a reaction equivalence ratio of mixed aqueous solution: lime milk = 1: 1.04. The mixture was continuously poured into the reaction tank with stirring for reaction. Furthermore, this reaction product was emulsified in an aqueous sodium chloride solution having a chloride ion concentration of 2.0 mol / liter, and the mixture was placed in an autoclave equipped with a stirrer and having a volume of 100 liters.
Hydrothermal treatment for hours. After that, filter with a filter press,
The target composite metal hydroxide was obtained by washing with water, dehydration, drying in an oven and pulverization.

[0050]

Example 4 In Example 3, the reaction equivalent ratio of the mixed aqueous solution and lime milk was set to mixed aqueous solution: lime milk = 1: 1.20. Other than that was carried out similarly to Example 3, and obtained the target composite metal hydroxide.

[0051]

Example 5 First-grade reagent magnesium nitrate and zinc nitrate were dissolved in ion-exchanged water to prepare 1 liter of a mixed aqueous solution having a Mg ion concentration of 0.9 mol / liter and a Zn ion concentration of 0.1 mol / liter. Also, as an alkaline substance, a 2.04 mol / liter sodium hydroxide aqueous solution 1
1 liter is prepared, and both are in a reaction equivalence ratio, and a mixed aqueous solution:
The above mixed aqueous solution was dropped into the aqueous sodium hydroxide solution with stirring so that the sodium hydroxide was 1: 1.02, and the reaction was carried out to obtain a reaction product. Further, this reaction product was emulsified in an aqueous sodium chloride solution having a chloride ion concentration of 1 mol / liter, placed in an autoclave with a stirrer and having a volume of 3 liters, and hydrothermally treated at 150 ° C. for 2 hours. Then, it was filtered with a vacuum filter, washed with water, dried in an oven, and then pulverized to obtain the target composite metal hydroxide.

[0052]

Example 6 1530 liters of seawater decarbonated (M
Zinc nitrate was added to a g ion concentration of 0.032 mol / liter so that the Zn ion concentration would be 0.002 mol / liter to prepare synthetic seawater. Further, as an alkaline substance, 51 liters of lime milk having an alkali ion concentration of 1.07 mol / liter was prepared, and both of them were used in a reaction equivalent ratio.
Synthetic seawater: lime milk = 1: 1.05 was continuously poured into a continuous reaction tank having an effective capacity of 250 liters with stirring to cause a reaction. Further, this reaction product was emulsified in an aqueous calcium chloride solution having a chloride ion concentration of 1.2 mol / liter, placed in an autoclave equipped with a stirrer and having a capacity of 100 liter, and hydrothermally treated at 150 ° C. for 2 hours. After that, filtration with a filter press, washing with water, dehydration, drying in an oven and pulverization were carried out to obtain the target composite metal hydroxide.

[0053]

Example 7 The reaction mother liquor after hydrothermal treatment at 150 ° C. for 2 hours in Example 6 was cooled to 100 ° C.
3.5 liters of a nickel chloride aqueous solution having a Ni ion concentration of 0.3 mol / liter was added with stirring and aged by heating at 100 ° C. for 30 minutes. Other than that was obtained in the same manner as in Example 6 to obtain a target composite metal hydroxide.

[0054]

Example 8 In Example 7, an aqueous solution of nickel chloride was added at a ratio of 1 mol% to the produced composite metal hydroxide. Other than that was carried out similarly to Example 7, and obtained the target composite metal hydroxide.

[0055]

[Example 9] In Example 7, an aqueous solution of nickel chloride was added at a ratio of 5 mol% to the produced mixed metal hydroxide, and the mixture was aged at 150 ° C for 30 minutes. Other than that was carried out similarly to Example 7, and obtained the target composite metal hydroxide.

[0056]

Example 10 In Example 3, the reaction mother liquor after hydrothermal treatment at 150 ° C. for 2 hours was cooled to 100 ° C., and 3.9 liters of an aqueous nickel chloride solution having a Ni ion concentration of 0.4 mol / liter was added thereto. Is added with stirring, and the temperature is 100 ° C.
It was heated and aged for 30 minutes. Other than that was obtained in the same manner as in Example 6 to obtain a target composite metal hydroxide.

[0057]

[Comparative Example 1] Dissolving first-grade reagent zinc chloride in bitter juice and adding Mg
Ion concentration 1.7 mol / liter, Zn ion concentration 0.
30 liters of a mixed aqueous solution of 085 mol / liter was prepared. As an alkaline substance, 46 liters of lime milk having an alkali ion concentration of 1.0 mol / liter was prepared, and both were mixed at a reaction equivalent ratio.
A continuous reaction tank having an effective volume of 2.5 liters was continuously added with stirring so as to be 0.9 and reacted. Further, this reaction product was placed in an autoclave equipped with a stirrer and having a capacity of 100 liters, and subjected to hydrothermal treatment at 150 ° C. for 2 hours. Then, the reaction product was obtained by filtering with a filter press, washing with water, dehydration, drying in an oven and crushing.

[0058]

Comparative Example 2 The reaction equivalent ratio of the mixed aqueous solution and the lime milk was set to mixed aqueous solution: lime milk = 1: 1.05. A reaction product was obtained in the same manner as in Comparative Example 1 except for the above.

[0059]

Comparative Example 3 In Example 5, the reaction equivalent ratio of the mixed aqueous solution and sodium hydroxide was set to mixed aqueous solution: sodium hydroxide = 1: 1.25. A reaction product was obtained in the same manner as in Example 5 except for the above.

[0060]

Comparative Example 4 In Example 5, the reaction equivalent ratio of the mixed aqueous solution and sodium hydroxide was set to mixed aqueous solution: sodium hydroxide = 1: 1.00. A reaction product was obtained in the same manner as in Example 5 except for the above.

[0061]

[Comparative Example 5] Mg ion concentration 1.1 mol / liter, Z
A mixed aqueous solution having an n ion concentration of 0.055 mol / liter was prepared. In addition, the reaction equivalent ratio of the mixed aqueous solution and lime milk,
The mixed aqueous solution: lime milk = 1: 1.05 was set. A reaction product was obtained in the same manner as in Comparative Example 1 except for the above.

[0062]

[Comparative Example 6] In Example 1, the mixed aqueous solution was treated with a Mg ion concentration of 0.14 mol / liter and a Zn ion concentration of 0.0.
It was set to 19 mol / liter. A reaction product was obtained in the same manner as in Example 1 except for the above.

[0063]

[Comparative Example 7] In Example 1, the mixed aqueous solution was treated with a Mg ion concentration of 0.88 mol / liter and a Zn ion concentration of 0.1.
It was set to 2 mol / liter. A reaction product was obtained in the same manner as in Example 1 except for the above.

The chemical composition, average secondary particle size and BET specific surface area of each composite metal hydroxide thus obtained were measured. The results are shown in Tables 1 and 2 below.

With respect to the above chemical composition, the amount of contained elements is quantified by a fluorescent X-ray analysis, a complex metal hydroxide dissolved in hydrochloric acid, and a chelate titration method, ICP emission spectroscopic analysis, etc.
In addition, identification and measurement of the lattice constant were carried out by X-ray diffraction analysis to determine whether or not uniform solid solution was achieved.

The average secondary particle diameter was measured by the Microtrack method after ultrasonically dispersing the sample powder in a 0.2% sodium hexametaphosphate aqueous solution.

The BET specific surface area was measured by the N ₂ adsorption method.

[0068]

[Table 1]

[0069]

[Table 2]

From the above Tables 1 and 2, it can be seen that a uniform solid solution was obtained in all Examples.

[0071]

Examples 11 to 15 Next, each composite metal hydroxide (Example product) shown in Table 3 below was suspended in water, heated to 70 ° C. under stirring, and then dissolved in advance. The surface treatment was carried out by adding 2% by weight of oleic acid, which was set aside, to the complex metal hydroxide of sodium oleate. Then, it was dehydrated, washed with water, and dried in an oven.

As test materials, 0.2 part of an antioxidant and the following table were used per 100 parts of ethylene-ethyl acrylate copolymer (ethylene acrylate content: 15% by weight, manufactured by Nippon Petrochemical Co., Ltd.). Add each surface-treated composite metal hydroxide (Example product) at the ratio shown in 3,
Mixed with a blender. After mixing, use a biaxial roll for 13
The mixture was kneaded at 0 ° C. and press-molded at 160 ° C. to form a sheet having a thickness of 1 mm, and a thickness of about 3.2 mm (1/8).
Inch) sheets were each molded. Then, each of the above sheets is punched into a dumbbell shape and a strip shape,
A test sample was used. For these test samples, the tensile test is based on JIS C3005, and the flame retardant test is UL9.
It carried out based on 4VE.

[0073]

[Table 3]

[0074]

Comparative Examples 8 to 11 Each reaction product (comparative example product) shown in Table 4 below and Mg (OH) ₂ were used in the proportions shown in the same table. Other than that, each sheet was molded in the same manner as in Examples 12 to 19 above. Then, each of the above-mentioned sheets was punched out into a dumbbell shape and a strip shape to obtain test samples. For these test samples, a tensile test is conducted according to JIS C3005.
The flame retardancy test was carried out based on UL94VE.

[0075]

[Table 4]

The results of the flame retardant test and the tensile test using these test samples are also shown in Tables 5 and 6 below.

[0077]

[Table 5]

[0078]

[Table 6]

From the above Tables 5 and 6, it can be seen that the tensile strength is low and the mechanical strength is poor for all the comparative examples. Moreover, in Comparative Examples 8 to 10, good flame retardancy could not be obtained in the flame retardant test. On the other hand, in all the example products, although the compounding amount was smaller than that in the comparative example product, good evaluation results were obtained regarding the result of the flame retardant test. Further, the tensile strength of the example products is higher than that of all the comparative example products, and it is clear that all the example products have high flame retardancy and excellent mechanical strength.

[0080]

INDUSTRIAL APPLICABILITY As described above, the present invention provides a Zn-containing Mg aqueous solution having a specific Mg ion concentration and an alkaline substance,
By reacting at a predetermined reaction equivalence ratio, the composite metal hydroxide represented by the above formula (1) is produced. For this reason, Z, which is a uniform solid solution that was difficult to obtain by conventional synthesis,
An n-solid solution Mg-based composite metal hydroxide is obtained. further,
The composite metal hydroxide of the above formula (1) produced by aging the composite metal hydroxide obtained at this reaction equivalence ratio in an aqueous medium having a specific chloride ion concentration under predetermined temperature conditions. Makes it possible to control the crystal shape, and the occurrence of secondary aggregation is suppressed.

Further, water-soluble Ni is added to the composite metal hydroxide of the above formula (1) in the presence of a reaction mother liquor under a predetermined temperature condition.
By adding the compound solution, the composite metal hydroxide represented by the above formula (2) in which only the crystal surface portion is replaced with Ni is obtained. The composite metal hydroxide thus obtained is a uniform solid solution, and a Zn / Ni solid solution Mg-based composite metal hydroxide can be obtained. Therefore, a flame-retardant polymer composition obtained by containing the composite metal hydroxide represented by the above formulas (1) and (2) in a predetermined amount with respect to the polymer compound has been conventionally used. Although it has a lower compounding ratio, it exhibits high flame retardancy and also has excellent mechanical strength.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display area C09K 21/14 C09K 21/14

Claims (6)

[Claims] 1. An alkaline substance (Y) is added to a magnesium-containing aqueous solution (X) containing a water-soluble zinc compound and having a magnesium ion concentration of 0.01 to 1 mol / liter.
In the reaction equivalent ratio (X: Y), X: Y = 1: 1.01
A process for producing a composite metal hydroxide, which comprises reacting at 1: 1.20. 2. The method for producing a composite metal hydroxide according to claim 1, wherein the produced composite metal hydroxide is in a chlorine-containing aqueous medium having a chloride ion concentration of 0.5 to 2.0 mol / liter. And a hydrothermal treatment in the temperature range of 100 to 200 ° C., a method for producing a composite metal hydroxide. 3. The method for producing a composite metal hydroxide according to claim 2, wherein the produced composite metal hydroxide is heated in the temperature range of 80 to 150 ° C. in the presence of a reaction mother liquor to be water-soluble. A method for producing a composite metal hydroxide, wherein only the crystal surface portion of the composite metal hydroxide is replaced with nickel by adding a nickel compound solution. 4. A composite metal hydroxide represented by the following formula (1) obtained by the method for producing a composite metal hydroxide according to claim 1 or 2. [Image Omitted] Mg _1-x Zn _x (OH) ₂ (1) [In the formula (1), x is a positive number of 0.003 ≦ x ≦ 0.1. ] 5. A composite metal hydroxide represented by the following formula (2) obtained by the method for producing a composite metal hydroxide according to claim 3. _{Embedded image} Mg _1-xy Zn _x Ni _y (OH) ₂ (2) [In the formula (2), x is a positive number of 0.003 ≦ x ≦ 0.1, y
Is a positive number of 0.01 ≦ y ≦ 0.05. ] 6. The composite metal hydroxide according to claim 4 or the composite metal hydroxide according to claim 5 is contained within a range of 80 to 150 parts by weight with respect to 100 parts by weight of the polymer compound. A flame-retardant polymer composition characterized by the above.