JPH1160825A - Flame retardant for polyolefin resin and flame-retardant polyolefin resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a nonhalogen flame retardant having a marked effect of imparting flame retardancy by mixing a nitrogenous compound being an isocyanuric acid (derivative) with ammonium polyphosphate, titanium dioxide and silicon dioxide in a specified ratio. SOLUTION: This retardant is prepared by mixing 5-40 wt.% nitrogenous compound represented by the formula (wherein R<1> to R<3> are each H, a 1-16C hydroxyalkyl, a dihydroxylalkyl, a hydroxyaryl or a dihydroxyaryl) with 40-94.9 wt.% ammonium polyphosphate, 0.05-10 wt.% titanium dioxide and 0.05-10 wt.% silicon dioxide. Among the nitrogenous compounds represented by the formula, tris(2-hydroxyethyl) isocyanurate can be desirably used from the aspects of affinity and an effect of imparting flame retardancy. This retardant is used in an amount of usually 5-200 pts.wt. per 100 pts.wt. polyolefin resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a flame retardant for a polyolefin resin and a flame-retardant polyolefin resin composition.

[0002]

2. Description of the Related Art Many polyolefin resins are inherently flammable resins, and are required to be flame-retardant materials in accordance with the expansion of use in recent years. Have been. As a method of making a polyolefin resin flame-retardant, a method of adding a halogen-containing compound has been generally used. These flame retardant treatments do have a flame retardant effect, and the reduction in moldability and the mechanical strength of molded products are relatively small.However, a large amount of gas is generated during processing and combustion, causing corrosion of equipment. In addition, there is a strong demand for non-halogen flame retardant treatment from the viewpoint of safety.

Under such circumstances, aluminum hydroxide, magnesium hydroxide, which do not generate harmful gas during combustion,
Investigation of resin flame retardation by adding hydrated metal oxides such as basic magnesium carbonate has been actively conducted. However, in order to impart sufficient flame retardancy to a polyolefin resin which is flammable only with these hydrated metal oxides, a large amount of the hydrated metal oxides must be added, and as a result, Various products obtained from these polyolefin-based resin compositions have remarkable reductions in mechanical strength and have various practical problems.

The flame retardant disclosed in JP-A-5-50536 is a combination of a condensed phosphoric acid compound and a triazine compound. However, a polyolefin resin is flame retardant (oxygen according to JIS K7201). In order to obtain an index of 28 or more), it is necessary to add a large amount of the above-mentioned flame retardant, and the mechanical strength of the obtained polyolefin resin product is remarkably reduced, which is not preferable.

Japanese Patent Application Laid-Open No. 60-152542 discloses that a polyethylene-based resin or a copolymer resin mainly composed of ethylene is added with a phosphorus-based flame retardant and triphenylantimony which do not impair the transparency of these resins. Although a flame-retardant transparent polyolefin resin composition is disclosed, a combination of the phosphorus-based flame retardant and triphenylantimony is intended to obtain a flame-retardant polyolefin resin composition having an oxygen index of 28 or more according to the standard. If this is the case, it is necessary to add a large amount of the above-mentioned phosphorus-based flame retardant and triphenylantimony, and the mechanical strength of the resulting polyolefin-based resin product is significantly reduced.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and has as its object to provide a flame retardant for a non-halogen polyolefin resin having a remarkable flame retarding effect and a flame retardant for the same. An object of the present invention is to provide a polyolefin-based resin composition having excellent flame retardancy using the same.

[0007]

According to the first aspect of the present invention, a nitrogen-containing compound represented by the following structural formula is 5 to 40% by weight, and ammonium polyphosphate is 40 to 94.9% by weight.
And a flame retardant for a polyolefin resin, comprising 0.05 to 10% by weight of titanium dioxide and 0.05 to 10% by weight of silicon dioxide.

Embedded image (In the formula, R ^{1 to} R ³ are each hydrogen or carbon number 1 to 1
6, a hydroxyalkyl group, a dihydroxyalkyl group,
It represents a hydroxyaryl group or a dihydroxyaryl group. )

According to a second aspect of the present invention, there is provided a flame retardant for a polyolefin resin according to the first aspect, wherein the nitrogen-containing compound is tris (2-hydroxyethyl) isocyanurate. is there.

According to a third aspect of the present invention, there is provided a polyolefin-based resin composition comprising the flame retardant for a polyolefin-based resin according to the first aspect in an amount of 5 to 200 parts by weight per 100 parts by weight of the polyolefin-based resin. It is assumed that.

The nitrogen-containing compound used in the present invention is represented by the following structural formula.

[0011]

Embedded image (In the formula, R ^{1 to} R ³ are each hydrogen or carbon number 1 to 1
6, a hydroxyalkyl group, a dihydroxyalkyl group,
It represents a hydroxyaryl group or a dihydroxyaryl group. )

Specific examples of the nitrogen-containing compound include, for example, isocyanuric acid, mono (hydroxymethyl) isocyanurate, bis (hydroxymethyl) isocyanurate, tris (hydroxymethyl) isocyanurate, and mono (dihydroxymethyl) isocyanate. Nurate, bis (dihydroxymethyl) isocyanurate, tris (dihydroxymethyl) isocyanurate, mono (2-hydroxyethyl) isocyanurate, bis (2
-Hydroxyethyl) isocyanurate, tris (2-
Hydroxyethyl) isocyanurate, tris (1,2
-Dihydroxyethyl) isocyanurate, tris (3
-Hydroxypropyl) isocyanurate, tris (2,3-dihydroxypropyl) isocyanurate,
Tris (4-hydroxybutyl) isocyanurate, tris (3,4-dihydroxybutyl) isocyanurate, tris (8-hydroxyoctyl) isocyanurate, tris (4-hydroxyphenyl) isocyanurate, tris (2,4-dihydroxyphenyl) ) Isocyanurate, tris (2,3-dihydroxyphenyl) isocyanurate and the like. Above all, tris (2-hydroxyethyl) isocyanurate is preferably used from the viewpoint of affinity with a polyolefin-based resin and flame retardant effect.

Among the above nitrogen-containing compounds, tris (2-hydroxyethyl) isocyanurate (decomposition temperature: 207 to 314 ° C.) used in the invention of claim 2 is a temperature range including the lower limit of the decomposition temperature of the polyolefin resin. When the polyolefin resin is burned, incombustible gas is generated smoothly during the combustion of the polyolefin resin, which is extremely effective in imparting the flame retardancy of the polyolefin resin in combination with the nonflammable film formed by ammonium polyphosphate. Works.

Furthermore, tris (2-hydroxyethyl) isocyanurate has extremely good compatibility with polyolefin resins, and therefore does not affect the excellent physical properties of polyolefin resin products without causing flame retardancy to the polyolefin resins. It is possible to give the property.

The above ammonium polyphosphate used in the present invention has a general formula (NH ₄ PO ₃ ) _n (where n is 100
-1,000 is preferable from the viewpoint of dispersibility in the polyolefin resin. ) Is a free-flowing powder that is hardly soluble in water. The ammonium polyphosphate may be used as a free-flowing powder that is hardly soluble in water and has a surface coated with a melamine-formaldehyde resin or the like.

Titanium dioxide and silicon dioxide used in the present invention each have an action of strongly catalyzing a reaction in the direction in which the above-mentioned ammonium polyphosphate is further polymerized when the polyolefin resin is burned, so that ammonium polyphosphate is formed. Reinforce nonflammable coatings. The present invention uses titanium dioxide and silicon dioxide together,
This is based on the fact that a greater effect is obtained than when each is used alone, and in combination with the action of the above-mentioned nitrogen-containing compound, acts extremely effectively on imparting flame retardancy to the polyolefin resin.

The flame retardant used in the present invention comprises 5 to 40% by weight of a nitrogen-containing compound represented by the following structural formula, 40 to 94.9% by weight of ammonium polyphosphate, and 0.1% of titanium dioxide.
05-10% by weight and silicon dioxide metal oxide 0.05-
However, if the composition is out of the above three components, the balance between the amount of nonflammable gas generated and the amount of nonflammable film formed is lost, and sufficient flame retardancy cannot be imparted to the polyolefin resin. .

[0018]

Embedded image (In the formula, R ^{1 to} R ³ are each hydrogen or carbon number 1 to 1
6, a hydroxyalkyl group, a dihydroxyalkyl group,
It represents a hydroxyaryl group or a dihydroxyaryl group. )

The polyolefin resin which can be made flame-retardant by the flame retardant of the present invention is not particularly limited, and may be polyethylene resin, polypropylene resin, poly (1-
Butene) -based resins, polypentene-based resins, and the like.
The polypropylene-based resin may be any of a homopolymer of propylene, a copolymer containing propylene as a main component, and a mixture thereof. Examples of the copolymer include a propylene-α-olefin copolymer containing a propylene component as a main component. As the α-olefin, propylene, 1-hexene, 4-methyl-1-
Examples thereof include pentene, 1-octene, 1-butene, and 1-pentene.

The polyethylene resin may be any of a homopolymer of ethylene (low density, medium density, high density), a copolymer containing ethylene as a main component, and a mixture thereof.
Examples of the copolymer include an ethylene-α-olefin copolymer containing ethylene as a main component. α
-As the olefin, ethylene, 1-hexene, 4-
Methyl-1-pentene, 1-octene, 1-butene, 1
-Pentene and the like. Further, as the copolymer other than the α-olefin, an ethylene-vinyl acetate copolymer, an ethylene-ethyl acrylate copolymer, or the like may be used.

The flame-retardant polyolefin resin composition of the invention according to claim 3 is prepared by adding 5 to 200 parts by weight, preferably 10 to 100 parts by weight of the flame retardant to 100 parts by weight of the polyolefin resin. Is used. When the amount is less than 5 parts by weight, the polyolefin-based resin composition does not have sufficient flame retardancy, and when it exceeds 200 parts by weight, various products molded from the obtained flame-retardant polyolefin-based resin composition Cannot be put to practical use.

In the present invention, in addition to the above four-component flame retardant, a flame retardant auxiliary comprising a hydrated metal oxide such as aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate and dawsonite may be added. . The amount of these flame retardant aids depends on the amount of the four-component flame retardant of the invention according to claim 1 and claim 2.
It is preferable to add 100 parts by weight or less per 100 parts by weight. When the amount exceeds 100 parts by weight,
Although high flame retardancy can be obtained, there is a possibility that mechanical strength is reduced and a product that can be used practically cannot be obtained. Above all,
When the polyolefin-based resin composition of the present invention is applied to a foamable resin composition, the foaming properties may be impaired, a fine and uniform foamed structure may not be obtained, and the appearance and the mechanical strength may be deteriorated.

The flame-retardant polyolefin-based resin composition of the present invention may further contain an antioxidant such as a phenol-based, amine-based, or sulfur-based resin, a stabilizer, a hydrocarbon-based, a fatty acid-based, a higher alcohol-based, an amide-based, or an ester. It is permissible to add a metal-based or metal soap-based lubricant or the like without departing from the spirit of the present invention.

(Function) As described above, the flame retardant for a polyolefin resin according to the first aspect of the present invention comprises 5 to 40% by weight of a nitrogen-containing compound represented by the above structural formula and 40 to 94. 9% by weight and titanium dioxide 0.0
5 to 10% by weight, and silicon dioxide metal oxide 0.05 to 1
0% by weight, the compound exhibits excellent combined flame retardancy which cannot be inferred from each of the ammonium polyphosphate and the nitrogen-containing compound represented by the structural formula. A flame-retardant polyolefin-based resin composition having excellent self-extinguishing properties by burning can be obtained. Further, when the flame retardant for a polyolefin resin according to the first aspect of the invention is applied to a polyolefin resin composition containing a foaming agent, the flame retardant polyolefin resin foam having excellent self-extinguishing properties due to non-halogen flame retardancy is obtained. You can get the body.

The flame retardant for a polyolefin resin of the invention according to claim 2 is, as described above, the flame retardant according to claim 1, wherein the nitrogen-containing compound is tris (2-hydroxyethyl).
Since it is isocyanurate, it has a decomposition temperature in the temperature range including the lower limit of the decomposition temperature of the polyolefin resin, and the complex with ammonium polyphosphate also has a decomposition temperature in the above temperature range (decomposition temperature: 252 to 640 ° C). Have
During the combustion of the polyolefin resin, the generation of nonflammable gas occurs smoothly, and in combination with the non-combustible coating formed by ammonium polyphosphate, acts extremely effectively on imparting flame retardancy to the polyolefin resin.

Furthermore, tris (2-hydroxyethyl) isocyanurate has extremely good compatibility with polyolefin resins, and therefore does not affect the excellent physical properties of the polyolefin resin products without affecting the flame retardancy of the polyolefin resins. It is possible to give the property. In particular, when the polyolefin resin composition of the present invention is applied to a foamable resin composition, a flame retardant for a polyolefin resin which does not adversely affect foaming properties and excellent physical properties of the polyolefin resin is provided. .

The flame-retardant polyolefin resin composition according to the third aspect of the present invention has remarkable flame retardancy as described above, does not generate harmful halogen-based gas during combustion, and is inexpensive. It has excellent features not found in the prior art in that it is inexpensive.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention and comparative examples will be described. In the examples, the combustion test was measured and evaluated by the following methods.

(Examples 1 to 6) and (Comparative Examples 1 to 3) Each component was melt-kneaded using a Labo Plastomill according to the composition shown in Table 1, and hot-pressed at a molding temperature in the table to obtain a test piece. Was prepared. The following tests were performed on the obtained test pieces. The results are shown in Table 1.

(Combustion test) A-1 test piece (length: 150 mm, width: 6.5 mm, thickness: 3.0 m) in accordance with JIS K7201 (Test method for flammability of organic materials for vehicle interior)
The oxygen index of m) was measured, and the evaluation was made in two stages: ：: oxygen index of 28 or more, x: less than 28.

In Examples 1 to 6 and Comparative Examples 1 to 3, the following components were used. Polyethylene resin: MI = 3.4, density 0.92 g /
cm ³ Nitrogen-containing compound: Tris (2-hydroxyethyl) isocyanurate [manufactured by Wako Pure Chemical Industries, Ltd.] Ammonium polyphosphate: manufactured by Hoechst, trade name “AP
P422 "Titanium dioxide: manufactured by Ishihara Sangyo Co., Ltd., trade name" MC90 "Silicon dioxide: manufactured by Asahi Glass Co., Ltd., trade name" Sildex H-5 "
1 "

[0032]

[Table 1]

[0033]

The flame retardant for a polyolefin resin according to the first aspect of the present invention is constituted as described above, and since the nonflammable film is strengthened and can surely conceal a fire source,
It shows excellent performance as a flame retardant for polyolefin-based resins, particularly, polyolefin-based resin foams containing many bubbles.

The flame retardant for a polyolefin resin of the invention according to claim 2 is, as described above, the flame retardant according to claim 1, wherein the nitrogen-containing compound is tris (2-hydroxyethyl).
Isocyanurate, the decomposition temperature of which exists in a temperature range including the lower limit of the decomposition temperature of the polyolefin resin,
Since the generation of nonflammable gas occurs smoothly and can conceal the fire source quickly, it is difficult to form a polyolefin resin, especially a polyolefin resin foam containing many bubbles, in combination with the above ammonium polyphosphate. Shows excellent performance as a fuel.

Furthermore, tris (2-hydroxyethyl) isocyanurate has extremely good compatibility with polyolefin resins, and is difficult to use in polyolefin resins which do not adversely affect the excellent physical properties of polyolefin resin products. Flammability can be imparted.

The flame-retardant polyolefin resin composition of the present invention according to claim 3 has remarkable flame retardancy as described above, and does not generate harmful halogen-based gas during combustion.
In addition, it has excellent features not found in the prior art in that it is inexpensive.

Claims (3)

[Claims] 1. A nitrogen-containing compound 5 represented by the following structural formula:
-40% by weight and ammonium polyphosphate.
A flame retardant for a polyolefin resin, comprising 9% by weight, 0.05 to 10% by weight of titanium dioxide and 0.05 to 10% by weight of silicon dioxide. Embedded image (In the formula, R ^{1 to} R ³ are each hydrogen or carbon number 1 to 1
6, a hydroxyalkyl group, a dihydroxyalkyl group,
It represents a hydroxyaryl group or a dihydroxyaryl group. ) 2. The flame retardant for a polyolefin resin according to claim 1, wherein the nitrogen-containing compound is tris (2-hydroxyethyl) isocyanurate. 3. The flame retardant for a polyolefin resin according to claim 1, which is added in an amount of 5 parts by weight per 100 parts by weight of the polyolefin resin.
A flame-retardant polyolefin-based resin composition obtained by adding about 200 parts by weight.