JP2010024382A - Flame-retardant resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame-retardant resin composition which exhibits excellent flame retardancy without using a halogen compound nor a phosphorous compound. <P>SOLUTION: The flame-retardant resin composition contains a resin A, a solid acid B, and an inorganic filler whose dehydration starts in a temperature range from -50°C being the thermal decomposition temperature of a mixture of A and B to +50°C. As the resin A, a compound containing an organic acid group and/or an organic acid ester group is preferable. As the solid acid B, a substance containing an oxide of silicon and nitrogen ion is preferable. As the inorganic filler C, a compound selected from the group comprising magnesium oxide, aluminum oxide, basic magnesium carbonate and hydrotalcite is preferable. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a flame retardant resin composition that does not have a halogen atom and can exhibit higher flame retardancy than a conventional inorganic flame retardant.

  Conventionally, a material to which a metal hydroxide is added is known as a flame retardant containing no halogen. In order to achieve high flame retardant performance, a large amount of the metal hydroxide must be added. By reducing the relative resin amount, physical properties other than flame retardant, such as moldability and mechanical properties, etc. There was a problem that decreased. As means for solving these problems, the following techniques have already been disclosed.

  Japanese Patent Laid-Open No. 2002-302613 (Patent Document 1) adds a nitrate metal salt as an oxidative decomposition accelerator for a resin, and the resin during combustion instantaneously oxidatively decomposes and liquefies to obtain combustion inhibition. ing. However, since the oxidative decomposition liquid is dripped at the time of combustion, there is a concern that the combustion is continued at the dropping point.

  In Japanese translations of PCT publication No. 2007-507564 (Patent Document 2), by adding ammonium polyphosphate and pentaerythritol to a resin material, foaming and crosslinking of the resin are promoted during combustion to impart flame retardancy. However, due to the presence of phosphorus, there are concerns about soil and water pollution and adverse effects on the human body.

JP 2002-302613 A Special Table 2007-507564

  The subject of this invention is providing the flame-retardant resin composition which expresses the outstanding flame retardance, without using a halogen-type compound and a phosphorus compound.

Conventionally, in a non-halogen flame retardant material, a method of adding a large amount of an inorganic filler to a main resin has been common. Alternatively, as in Patent Document 1, a technique has been used in which the main material is rapidly decomposed to a low molecular weight and liquefied to extinguish the flame.
In the present invention, a flame-retardant resin composition that does not use a halogen-based compound or a phosphorus-based compound, can exhibit higher flame retardance than before, and does not cause liquefaction of the main resin during combustion. Offer things.

That is, this invention includes the following aspects.
1. A flame retardant resin composition comprising resin A, solid acid B, and inorganic filler C that starts dehydration at a temperature equal to or higher than a thermal decomposition temperature of −50 ° C. of a mixture of A and B.
2. 2. The flame retardant resin composition according to 1, wherein the inorganic filler C starts dehydration at a temperature equal to or lower than a thermal decomposition temperature of the mixture of A and B + 50 ° C.
3. 3. The flame retardant resin composition according to 1 or 2 above, wherein the solid acid B is a porous body containing an oxide of silicon.
4). 4. The flame retardant resin composition according to 3 above, wherein the solid acid B further contains an oxide of aluminum.
5). 3. The flame retardant resin composition according to 1 or 2 above, wherein the solid acid B is silica alumina.
6). 6. The flame retardant resin composition according to any one of 1 to 5, wherein the solid acid B further contains nitrogen-containing ions.
7). 7. The flame retardant resin composition as described in 6 above, wherein the nitrogen-containing ions are ammonium ions and / or nitrate ions.
8). 2. The flame retardant resin composition according to 1, wherein the thermal decomposition temperature of the resin A is higher than the thermal decomposition temperature of the mixture of A and the solid acid B.
9. 9. The flame retardant resin composition as described in 8 above, wherein the resin A has an organic acid group and / or an organic acid ester group.
10. 10. The flame retardant resin composition according to 9, wherein the organic acid group is a carboxylic acid group, and the organic acid ester group is a carboxylic acid ester group.
11. 3. The flame retardant resin composition according to 1 or 2, wherein the inorganic filler C is one or more selected from the group consisting of magnesium hydroxide, aluminum hydroxide, basic magnesium carbonate, and hydrotalcite.

  Addition of the flame retardant resin composition of the present invention improves the flame retardancy of the main resin material.

  The flame retardant resin composition of the present invention comprises a resin A, a solid acid B, and an inorganic filler C that starts dehydration at a temperature equal to or higher than the thermal decomposition temperature −50 ° C. of the mixture of A and B. It is a thing. Furthermore, the inorganic filler C preferably starts dehydration at a temperature not higher than + 50 ° C. of the thermal decomposition temperature of the mixture of A and B.

  The thermal decomposition temperature can be determined by measuring the weight loss at the time of temperature increase at a constant rate by simultaneous differential thermothermal weight measurement.

  The thermal decomposition temperature in the present invention refers to the thermal decomposition start temperature of each substance, and means the weight decrease start temperature in the air atmosphere of the measurement substance confirmed by the analysis method. In the case of a mixture, it refers to the initial weight loss onset temperature. There is a change in the slope of the data at the start of weight loss. The temperature at the point where the tangent lines of the slope before and after the slope change intersect is defined as the thermal decomposition temperature. If the slope after the change cannot be determined, the thermal decomposition temperature cannot be determined. In such a case, the thermal decomposition temperature is determined as a temperature range within the range of possibilities. When the thermal decomposition temperatures of different substances are compared, if the temperature A falls within the temperature range B, it is regarded as an equivalent temperature. Further, comparison between measurement substances is performed using data obtained by the same measurement method. The relationship between the pyrolysis temperature materials obtained in each measurement is as follows.

T _{A + B} : thermal decomposition temperature of a mixture of resin A and solid acid B,
T _A : thermal decomposition temperature of resin A,
T _C : Dehydration start temperature of the inorganic filler C

When the rate of temperature increase is 10 ° C./min, the thermal decomposition temperature is T (° C.), and T _{A + B} −50 ≦ T _C , preferably T _{A + B} −50 ≦ T _C ≦ T _{A + B} is +50, also, if T _{a +} B <T _a, further improves the flame retardancy.

  The solid acid B used in the present invention refers to a solid acid whose surface exhibits acid properties. The acid point only needs to be present on the surface, and may be an acidic substance-supported product. The solid acid B is suitably a porous body having pores of 100 nanometers or less and / or layers. Moreover, it is also called solid acid B when it contains nitrogen-containing ions. The acid point may be present in the solid acid B when it is completed as a flame retardant resin composition, or may be generated by heating in the course of combustion. For example, the solid acid B is also changed to an ammonium type by adsorption of ammonia.

Solid acid B is a porous body comprising SiO ₂ or SiO ₂ / Al ₂ O _3,, a further porous body comprising other metal oxides. Specifically, natural or synthetic silicate materials, alumina silicate materials, and clay minerals. For example, silica, silica alumina, aluminum modified silica, aluminum silicate, polysilicic acid, polyaluminosilicate mordenite, zeolite, titania, zirconia, heteropolyacid, montmorillonite, magatiite, saponite, fullerhectorite, laponite, sepiolite, attapulgite, hect Mainly includes light, beidellite, vermiculite, kaolinite, nontronite, bentonite, smectite, hydrotalcite. These may be used individually by 1 type and may use 2 or more types together.

  Among the solid acids B, those further containing nitrogen-containing ions are preferable because flame retardancy efficiency can be improved. In particular, those containing ammonium ions and / or nitrate ions are preferred. Examples of the method for incorporating the substance containing nitrogen into the solid acid B include the following. During the synthesis of solid acid B, a nitrogen-containing compound is added to the ingredients. The solid acid B is treated by contacting with ammonia gas or immersing in ammonia water. Alternatively, the solid acid B is loaded with a nitrogen-containing compound such as ammonium salt or nitrate. Examples of the ammonium salt include ammonium sulfate, ammonium nitrate, ammonium carbonate, and ammonium acetate. Examples of nitrates include potassium nitrate, sodium nitrate, calcium nitrate, magnesium nitrate, and ammonium nitrate. Examples of the solid acid B further containing nitrogen-containing ions include ammonium-type silica alumina, various ammonium-type zeolites, nitric acid-treated aluminum silicate, potassium nitrate-supported aluminum silicate, and the like. In addition, at the stage of finishing the solid acid B, a treatment that removes a substance that is not stable to the solid acid B may be performed by purging with an inert gas or washing with water.

  Resin A is selected in consideration of the functionality and compatibility of the resin material to which the flame retardant resin composition is finally added. Examples of the resin A include a thermosetting resin and a thermoplastic resin, and examples of the thermosetting resin include a phenol resin, an epoxy resin, a melamine resin, a urea resin, an unsaturated polyester resin, and a polyimide resin. Examples of the thermoplastic resin include polyolefin resins such as polyethylene and polypropylene, polystyrene resin, polyvinyl acetate resin, acrylonitrile butadiene styrene resin, acrylic resin, polyethylene terephthalate, polycarbonate, polylactic acid, and polyamide resin. These may be used alone or in combination of two or more.

  Furthermore, what has further an organic acid group and / or an organic acid ester group is preferable. Particularly preferred are those further having a carboxylic acid group and / or a carboxylic acid ester group. Furthermore, acrylic acid group, maleic acid group, fumaric acid group, itaconic acid group, methacrylic acid group, sorbic acid group, crotonic acid group, citraconic acid group, phthalic acid group, terephthalic acid group, succinic acid group, adipic acid group, etc. A copolymer obtained by copolymerizing an unsaturated carboxylic acid group or an unsaturated carboxylic acid ester group is preferred.

  The inorganic filler C starts dehydration at a temperature equal to or higher than the thermal decomposition temperature −50 ° C. of the mixture of A and B, preferably dehydrated at a temperature equal to or lower than the thermal decomposition temperature of the mixture of A and B + 50 ° C. It is a substance that starts. The dehydration start temperature means a temperature at which weight reduction due to dehydration starts when the temperature is increased at a constant rate. The weight loss at the time of temperature rise can be determined by simultaneous differential thermothermal weight measurement (TG / DTA). Moreover, it can be confirmed by mass spectrometry (MS) whether the weight loss at the time of temperature rise originates from dehydration.

Similar to the thermal decomposition temperature, the dehydration start temperature is determined at the point where the tangent lines of the inclination intersect.
As the inorganic filler C, hydrates of inorganic metal compounds such as aluminum hydroxide, magnesium hydroxide, hydrotalcite, calcium hydroxide, barium hydroxide, zirconium hydroxide, tin oxide hydrate, zinc borate , Zinc metaborate, barium metaborate, zinc carbonate, magnesium carbonate, mu calcium, calcium carbonate, calcium aluminate, barium carbonate and the like. These may be used alone or in combination of two or more. In particular, a material selected from the group consisting of magnesium hydroxide, aluminum hydroxide, calcium hydroxide and hydrotalcite has an endothermic effect due to thermal decomposition or dehydration, and is preferable because of its high flame retardant effect.

  Further, the solid acid B and the inorganic filler C are preferably dispersed uniformly in the resin A because the flame retardancy efficiency is enhanced. The mixing of the resin A, the solid acid B, and the inorganic filler C is performed in a state where the resin A is heated to a temperature at which the resin A melts, and the solid acid B is added and mixed. Examples of the mixing method include an extruder and a mixer.

  Further, it is more effective that B and C have smaller particle diameters. For both B and C, the number average particle diameter is preferably 100 μm or less, more preferably 10 μm or less. The lower limit of the number average particle diameter is 10 nm. The number average particle size is determined by a particle size distribution measurement method using a laser diffraction / scattering method, a laser Doppler method, or a particle size measurement method using particle image observation. When the number average particle diameter exceeds 100 μm, the flame retardant effect is insufficient, while when it is less than 10 nm, handling becomes difficult.

The mixing ratio of A and (B + C) is preferably A: (B + C) = 100: 50 to 250, more preferably 100: 100 to 200, as a mass ratio. When the mass ratio (B + C) is less than 50 with respect to A100, the flame retardant effect is insufficient, and when it exceeds 250, molding is difficult.
The mixing ratio of B and C is preferably B: C = 0.1 to 100: 100, more preferably 1 to 40: 100 in terms of mass ratio. If the mass mixing ratio of B is less than 0.1 with respect to C100, the flame retardant effect is insufficient, and if it exceeds 100, the flame retardant effect is insufficient.

  The flame retardant resin composition described above can be added to various resin materials and used as a flame retardant.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited by the following example.

Example 1:
40 g of EEA (ethylene-ethyl acrylate copolymer: A1100 manufactured by Nippon Polyethylene Co., Ltd., thermal decomposition temperature: 330 ° C.) was melted with a mixer (capacity 100 cc) of Labo Plast Mill (manufactured by Toyo Seiki Co., Ltd.) Kneaded with 12 g of amorphous silica alumina (molar ratio: Si / Al = 2, number average particle size: 30 μm, preparation method will be described later). Next, 52 g of aluminum hydroxide (manufactured by Showa Denko KK, Hydylite H42M, number average particle size: 1 μm) was added. It knead | mixed for 10 minutes at 180 degreeC and 50 rpm.
Subsequently, a 2.5 mm thick sheet was produced with a press machine in which the above mixture was set at 170 ° C. After storage for 20 hours at 25 ° C. and 50% humidity, a UL94 V-0 combustion test was performed.
In addition, the measurement data of the thermal decomposition temperature of EEA (resin A) and ammonium type amorphous silica alumina (solid acid B) are shown in FIG. 1, and the measurement data of the dehydration start temperature of Heidilite H42M (inorganic filler C) is shown. It is shown in 2. The measurement method is differential thermothermogravimetric simultaneous measurement (TG / DTA), which shows the weight reduction rate when the temperature is raised from room temperature to 600 ° C. at a constant temperature of 10 ° C./min in an air atmosphere. The thermal decomposition temperature of A + B was 270 ° C., and the dehydration start temperature of C was 240 ° C. from the point where the tangent lines of the slope before and after the slope of the weight loss curve data changed.
The UL94 V-0 combustion test was performed according to the following procedure. A 2.5 mm-thick sheet was punched out with a die of a specified size, and five strip-shaped test pieces were obtained. The methane gas burner flame was applied to the lower end of the vertically supported test piece for 10 seconds and then released. When the flame disappeared, the burner flame was applied for another 10 seconds and then released. The time from completion of flame contact to flame extinction was measured twice for each test piece. However, when the flame did not extinguish after 120 seconds, the value was set to 120 seconds. The number average value up to a total of 10 flame extinction times was calculated and shown in Table 1 as the flame extinction time. In addition, when the time from the end of two flame contact to the extinction of each test piece is all within 10 seconds, the total of all is within 50 seconds, and the absorbent cotton placed under the test piece is not ignited, The test was passed, and is shown in Table 1 as A. The others were shown as B in Table 1 as rejected.
Ammonium type amorphous silica alumina (molar ratio: Si / Al = 2) was prepared by the following method. 20 g of proton-type amorphous silica alumina CSA-H (manufactured by Catalyst Kasei Kogyo Co., Ltd., number average particle size: 30 μm) was added to a mixed solution of 20 g of 28% by mass of ammonia water and 200 g of pure water, and then allowed to stand for 12 hours. I put it. The supernatant was taken out and 200 g of pure water was added and stirred. The supernatant was taken out through a centrifuge, and 200 g of pure water was added and stirred. The washing with pure water was repeated four times, and then the obtained cake was dried at 180 ° C. for 5 hours to obtain ammonium type amorphous silica alumina.

Example 2:
A sample was prepared in the same manner as in Example 1 except that Hydrite H42M was changed to hydrotalcite (manufactured by Kyowa Chemical Industry Co., Ltd., DHT-4A), and a UL94 V-0 combustion test was performed. The dehydration start temperature of DHT-4A was 250 ° C. (However, since it was heated at 180 ° C. until the preparation of the combustion test sample, it was the dehydration start temperature obtained by measurement after heating to 180 ° C. once. ).

Example 3:
A sample was prepared in the same manner as in Example except that the solid acid B was changed to the one prepared as follows. Nitrate ion-containing amorphous silica alumina (molar ratio: Si / Al = 2) was prepared by the following method. To an aqueous solution in which 50 g of potassium nitrate was dissolved in 200 g of pure water, 20 g of proton type amorphous silica alumina CSA-H (manufactured by Catalytic Chemical Industry Co., Ltd.) was added and stirred for 12 hours. The supernatant was taken out and 200 g of pure water was added and stirred. The supernatant was taken out through a centrifuge, and 200 g of pure water was added and stirred. The cake obtained after repeating washing with pure water 4 times was dried at 180 ° C. for 5 hours to obtain a nitrate ion-containing amorphous silica alumina.

Example 4:
A sample was prepared in the same manner as in Example except that the solid acid B was changed to the one prepared as follows. An ammonium type X type zeolite (molar ratio: Si / Al = 1.2) was prepared by the following method. After adding 20 g of molecular sieve 13X (manufactured by Showa Union Co., Ltd., number average particle size: 5 μm) to 200 g of pure water and adjusting the pH to 5 by adding nitric acid while stirring, the supernatant was taken out through a centrifuge. A mixed solution of 20 g of 28% by mass ammonia water and 200 g of pure water was added and stirred, and then allowed to stand for 12 hours. The supernatant was taken out and 200 g of pure water was added and stirred. The supernatant was taken out through a centrifuge, and 200 g of pure water was added and stirred. The cake obtained after repeating washing with pure water 4 times was dried at 180 ° C. for 5 hours to obtain a nitrate ion-containing amorphous silica alumina.

Comparative Example 1:
A sample was prepared in the same manner as in Example 1 except that 64 g of aluminum hydroxide (Hidilite H42M) was used and no ammonium type amorphous silica alumina was added, and a UL94 V-0 combustion test was performed.

Comparative Example 2:
A sample was prepared in the same manner as in Example 1 except that the ammonium type amorphous silica alumina was changed to molecular sieve 4A (manufactured by Showa Union Co., Ltd., number average particle size 10 μm), and a UL94 V-0 combustion test was performed. .

Comparative Example 3:
120 g of Hydrite H42M was added to 200 g of an aqueous solution containing 40 g of zinc nitrate and stirred. Thereafter, 64 g of an inorganic filler obtained by drying at 180 ° C. for 5 hours was used in the experiment, and a sample was prepared in the same manner as in Example 1 except that Hijilite H42M and solid acid B were not added. UL94 V-0 A combustion test was conducted. Moreover, the dehydration start temperature of this mixed inorganic filler C was 240 ° C.

[Explanation of results]
From the above UL94 V-0 combustion test, when a part of aluminum hydroxide was replaced with ammonium-type amorphous silica alumina, nitrate-containing amorphous silica alumina, or ammonium-type X-type zeolite, aluminum hydroxide before replacement Compared with the case of adding only the flame retardancy improved. On the other hand, when the sodium type A type zeolite was substituted, the flame retardancy decreased. In addition, when a part of aluminum hydroxide was replaced with zinc nitrate by impregnation treatment with aluminum hydroxide, dripping matter was generated during combustion, and the absorbent cotton was ignited, resulting in V-0 test failure.

The measurement data of the thermal decomposition temperature of the mixture of resin A (ethylene-ethyl acrylate copolymer) of Example 1 and solid acid B (ammonium type amorphous silica alumina) are shown. The measurement data of the dehydration start temperature of the inorganic filler C of Example 1 (aluminum hydroxide; Hygielite H42M manufactured by Showa Denko KK) are shown.

Claims (11)

  A flame retardant resin composition comprising resin A, solid acid B, and inorganic filler C that starts dehydration at a temperature equal to or higher than a thermal decomposition temperature of −50 ° C. of a mixture of A and B.   The flame retardant resin composition according to claim 1, wherein the inorganic filler C starts dehydration at a temperature equal to or lower than a thermal decomposition temperature of the mixture of A and B + 50 ° C.   The flame retardant resin composition according to claim 1 or 2, wherein the solid acid B is a porous body containing an oxide of silicon.   The flame retardant resin composition according to claim 3, wherein the solid acid B further contains an oxide of aluminum.   The flame retardant resin composition according to claim 1 or 2, wherein the solid acid B is silica alumina.   The flame retardant resin composition according to any one of claims 1 to 5, wherein the solid acid B further contains a nitrogen-containing ion.   The flame retardant resin composition according to claim 6, wherein the nitrogen-containing ions are ammonium ions and / or nitrate ions.   The flame-retardant resin composition according to claim 1, wherein the thermal decomposition temperature of the resin A is higher than the thermal decomposition temperature of a mixture of A and the solid acid B.   The flame-retardant resin composition according to claim 8, wherein the resin A has an organic acid group and / or an organic acid ester group.   The flame retardant resin composition according to claim 9, wherein the organic acid group is a carboxylic acid group, and the organic acid ester group is a carboxylic acid ester group.   The flame retardant resin composition according to claim 1 or 2, wherein the inorganic filler C is at least one selected from the group consisting of magnesium hydroxide, aluminum hydroxide, basic magnesium carbonate, and hydrotalcite.

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