JPH05295181A - Flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To provide the objective compsn. generating no halogen gas during burning and having improved mechanical and electrical properties by compounding a polyolefin, a specific adhesive polymer, and Mg(OH)2. CONSTITUTION:The compsn. is prepd. by compounding 100 pts.wt. base resin comprising 65-99wt.% polyolefin and 1-35wt.% adhesive polymer obtd. by introducing 0.1-10wt.% unsatd. carboxylic acid (deriv.) into a polyolefin skeleton with 5-200 pts.wt. Mg(OH)2 surface-treated with a dialcoholamine salt of a (di)alkyl phosphate represented by formula I (wherein R is a 10-30C alkyl or an alkenyl; m is 1-6; and n is 1 or 2) or an alkali metal salt of a (di)alkyl phosphate represented by formula II (wherein M is an alkali metal).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition, and more particularly, it does not generate a toxic halogen-based gas during combustion, and has excellent mechanical properties and electrical insulation properties. The present invention relates to a flame-retardant resin composition useful as a material for an insulating layer or a sheath.

[0002]

2. Description of the Related Art Recently, in underground malls and high-rise buildings, as a fire protection measure, communication cables and electric power cables that generate a small amount of smoke during combustion and do not generate halogen-based gas such as hydrogen halide gas are required. It is like this. In order to meet such a demand, development of a flame-retardant resin composition containing a non-halogen flame retardant as a material for an insulating layer or a sheath of a communication cable or an electric power cable is under way.

Such a flame-retardant resin composition is generally based on a thermoplastic resin such as polyolefin such as polyethylene or polypropylene, and a metal hydroxide such as aluminum hydroxide or magnesium hydroxide as a flame retardant. It is widely used that a certain amount of powder of the product is blended.

[0004]

By the way, in the case of the above-mentioned flame-retardant resin composition, in order to ensure sufficient flame retardancy, a large amount of the above-mentioned metal hydroxide powder as a flame retardant is blended. Will be needed. However, when a large amount of a metal hydroxide is blended, the excellent properties of the base polyolefin are impaired, and as a result, the mechanical properties of the resulting resin composition are poorly known as halogen-based compounds. There is a problem in that it is lower than that of the flammable resin composition.

Further, since the metal hydroxide compounded therein is hygroscopic in itself, when the resin composition is exposed to a moist environment or immersed in water, the insulation resistance of the resin composition is reduced. There is also the problem of a sharp drop. The present invention solves the above problems when a metal hydroxide is blended as a flame retardant, has more excellent flame retardancy, and is a non-halogen flame retardant resin that also has excellent mechanical properties and electrical insulation properties. The purpose is to provide a composition.

[0006]

In order to achieve the above object, in the present invention, polyolefins 65 to 99 are used.
50 parts by weight of magnesium hydroxide to 100 parts by weight of a base resin composed of 1% by weight and 1 to 35% by weight of adhesive polymer.
In a resin composition prepared by mixing 200 parts by weight, the adhesive polymer is formed by introducing an unsaturated carboxylic acid or a derivative thereof into the skeleton of polyolefin, and the magnesium hydroxide has the following formula:

[0007]

[Chemical 3]

(In the formula, R represents an alkyl group or an alkenyl group having 10 to 30 carbon atoms, m is an integer of 1 to 6, and n is 1 or 2.) Alcohol phosphate ester dialcohol amine salt , Or the following formula:

[0009]

[Chemical 4]

(Where R and n have the same meanings as above, and M
Represents an alkali metal), and a flame-retardant resin composition characterized by being surface-treated with an alcohol phosphoric acid ester alkali metal salt represented by the formula: The base resin of the flame-retardant resin composition of the present invention comprises a polyolefin and an adhesive polymer described below, and the flame retardant is magnesium hydroxide subjected to the surface treatment described below.

First, as the polyolefin constituting the base resin, for example, extremely low density polyethylene (VLDP)
E), linear low density polyethylene (LLDPE), low density polyethylene (LDPE), high density polyethylene (H
DPE), polypropylene, ethylene-propylene copolymer, ethylene-propylene-diene terpolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer (EEA) and the like. it can. Each of these may be used alone, or two or more kinds may be appropriately mixed and used.

Of these, VLDPE, EVA, EE
A is preferable because a large amount of metal hydroxide can be blended. EVA and EEA are more preferable because they have good flame retardancy, and EEA is particularly preferable because it can increase the volume resistivity of the obtained resin composition. The other component of the base resin is an adhesive polymer. This adhesive polymer has the above-mentioned polyolefin as a skeleton, and an unsaturated carboxylic acid such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, citraconic acid is added to the skeleton by, for example, a graft reaction. Or a metal salt of the above unsaturated carboxylic acid, an amide, an imide,
It is introduced by graft-polymerizing derivatives such as esters and anhydrides.

As such an adhesive polymer, for example, 0.1 to 10% by weight of maleic anhydride is added to a polyolefin such as LLDPE or EVA and the presence of an organic peroxide such as benzoyl peroxide or lauryl peroxide. The ones that have been graft-polymerized below can be mentioned,
Examples of commercially available products include N polymer (Nisseki Chemical Co., Ltd.)
Made).

This adhesive polymer functions to enhance the adhesiveness between the polyolefin and the metal hydroxide described later, and thus to improve the mechanical properties of the resin composition. Further, when the resin composition is immersed in warm water, it also has a function of preventing a decrease in volume resistivity of the resin composition. In the base resin, the blending ratio of the polyolefin and the adhesive polymer is from 65 to 99% by weight of the polyolefin and from 1 to 3 of the adhesive polymer.
It is set to 5% by weight.

When the amount of the adhesive polymer is less than 1% by weight (the amount of polyolefin is more than 99% by weight), the resulting resin composition has a small effect of improving the volume resistivity,
On the other hand, when the amount is more than 35% by weight (when the amount of polyolefin is less than 65% by weight), the volume resistivity of the resin composition is increased, but the hardness is also increased and the mechanical properties such as elongation are deteriorated. The preferred blending ratio of both is 85 to 97% by weight of polyolefin and 3 to 15% by weight of adhesive polymer.

In the resin composition of the present invention, the flame retardant compounded in the base resin is magnesium hydroxide powder.
Since metal hydroxides such as magnesium hydroxide generally do not wet well with the resin, when these are mixed with the resin, the metal hydroxide should be prepared beforehand with stearates, oleates, silanes or titanium couplings. A surface treatment is performed using the agent.

In the present invention, the magnesium hydroxide to be blended is surface-treated with an alcohol phosphate ester dialcohol amine salt represented by the formula (1) or an alcohol phosphate ester alcohol alkali metal salt represented by the formula (2). To be done. When magnesium hydroxide surface-treated with any of these compounds is used as a flame retardant, in the case of the base resin having the above-mentioned composition, the decrease in volume resistivity of the resulting resin composition when immersed in warm water is significantly suppressed.

The surface treatment of magnesium hydroxide may be carried out by mixing a powder of magnesium hydroxide with stirring and adding a predetermined amount of an aqueous solution in which the above compound is dissolved to the surface of the powder. The compounding amount of the surface-treated magnesium hydroxide in the base resin is set to 50 to 200 parts by weight with respect to 100 parts by weight of the base resin.

When the amount is less than 50 parts by weight, the flame retardancy of the obtained resin composition cannot be said to be good, and when it is more than 200 parts by weight, the mechanical properties of the resin composition are remarkably deteriorated. The resin composition of the present invention contains the above-mentioned components as essential components, and further includes known flame retardants such as antiaging agents, lubricants, plasticizers, fillers, pigments, carbon black, and red phosphorus.
You may add a suitable quantity of crosslinking agents.

The resin composition of the present invention can be easily produced by kneading the above components with a conventional kneader such as a mixing roll or a Banbury mixer. Further, by extruding and coating the outer periphery of a conductor or a communication wire with this resin composition, a flame-retardant power cable or communication cable that has excellent mechanical properties and electrical insulation properties and does not generate halogen-based gas during combustion can be provided. It can be manufactured.

[0021]

EXAMPLES Various flame retardants were prepared as follows. Flame retardant A 50% cumulative particle size measured by laser diffraction particle size measurement is 1.3μ
Water containing 1000 g of magnesium hydroxide powder of m 1
0 liter and the following formula:

[0022]

[Chemical 5]

Aqueous solution 1 in which 40 g of dioleyl alcohol phosphate ester diethanolamine represented by
The liters were mixed and the whole was stirred and mixed at 80 ° C. for 120 minutes. The mixed solution is filtered, and the filtered material is washed with water and then at 110 ° C.
The resulting dried cake was crushed with a Henschel mixer to obtain a flame retardant A. Flame retardant B The surface treatment agent has the following formula:

[0024]

[Chemical 6]

A flame retardant B was produced by carrying out a surface treatment in the same manner as in the case of the flame retardant A except that it was an aralkyl alcohol phosphate diethanolamine represented by Flame Retardant C The surface treatment agent is the above-mentioned dioleyl alcohol phosphate diethanolamine and the following formula:

[0026]

[Chemical 7]

Flame-retardant C was prepared by surface-treating in the same manner as flame-retardant A except that the mixture was 1: 1 with dilauryl alcohol phosphate sodium salt represented by .. Flame Retardant D Except that the surface treatment agent was sodium stearate represented by the following formula: CH ₃ (CH ₂ ) ₁₆ COONa,
The surface treatment was carried out in the same manner as in the case of the flame retardant A to produce the flame retardant D.

Flame Retardant E Flame Retardant D was surface-treated with the above-mentioned aralkyl alcohol phosphate diethanolamine, and the surface of magnesium hydroxide powder was sequentially coated with sodium stearate and aralkyl alcohol phosphate diethanolamine. Flame retardant E was produced.

Flame Retardant F The surface treatment agent is the above-mentioned dioleoyl alcohol phosphate diethanolamine and the following formula: CH ₃ (CH ₂ ) ₇ CH =
A flame retardant F was produced by performing surface treatment in the same manner as in the case of the flame retardant A, except that it was sodium oleate represented by CH (CH ₂ ) ₇ COONa.

Flame retardant G 50% cumulative particle size measured by laser diffraction particle size measurement is 1.3μ
Water containing 1000 g of aluminum hydroxide powder of m 1
0 liter and 1 liter of an aqueous solution of 40 g of sodium stearate are mixed, and the whole is heated at 80 ° C. for 120
Stir and mix for minutes. The mixed solution was filtered, the filtered material was washed with water and dried at 110 ° C. for 48 hours, and then the obtained dried cake was crushed with a Henschel mixer to obtain a flame retardant G.

Next, using the above flame retardants, the components shown in Table 1 were mixed in the indicated proportions, and sufficiently kneaded at 160 ° C. using an 8-inch twin-screw roll, and then the kneaded product was obtained. The sample sheet was molded by extrusion with a pressure press. The oxygen index and volume resistivity of each sheet were measured. The above results are collectively shown in Table 1. The volume resistivity is ○ when the volume resistivity after the sample sheet is immersed in warm water at 50 ° C. for 20 days is 1 × 10 ¹⁴ Ω · cm or more and is less than 1 × 10 ¹⁴ Ω · cm. If the case is x, then 5
After being immersed in warm water at 0 ° C for 40 days, the volume resistivity is 1
The case of × 10 ¹⁴ Ω · cm or more is indicated by ⊚.

[0032]

[Table 1]

[0033]

As is apparent from the above description, the resin composition of the present invention does not generate a halogen-based gas even when burned, has good mechanical properties, and has excellent electrical insulation properties.
In particular, since the volume resistivity does not decrease even when immersed in warm water, it is useful as a material for insulators and sheaths of power cables and communication cables.

Claims (1)

[Claims] 1. A base resin 100 comprising 65 to 99% by weight of a polyolefin and 1 to 35% by weight of an adhesive polymer.
In a resin composition obtained by mixing 50 to 200 parts by weight of magnesium hydroxide with respect to parts by weight, the adhesive polymer is formed by introducing an unsaturated carboxylic acid or a derivative thereof into the skeleton of polyolefin, Magnesium oxide has the following formula: (In the formula, R represents an alkyl group or an alkenyl group having 10 to 30 carbon atoms, m represents an integer of 1 to 6, and n represents 1 or 2), or an alcohol phosphate dialcohol amine salt, or The following formula: (In the formula, R and n have the same meanings as above, and M represents an alkali metal), and the surface treatment is carried out with an alcohol phosphoric acid ester alkali metal salt. ..