JPH06240055A - Flame-retardant resin composition - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a non-halogen flame-retardant resin composition that has both excellent flame retardancy and mechanical properties and is also excellent in heat resistance. [Structure] 100 parts by weight of a polyolefin polymer component containing 10% by weight or more of a random copolymer of ethylene and an unsaturated organic carboxylic acid has an organosiloxane oil having an amino group in the molecule and / or an amino group having an amino group in the molecule 5 to 30 parts by weight of an organosiloxane resin and 50 to 200 parts by weight of magnesium hydroxide are blended. [Effect] Excellent flame retardance with an oxygen index of 27-33, and 1.
A flame-retardant resin composition having a high tensile strength of ² kg / mm ² to 1.8 kg / mm ² and excellent heat resistance, and its practical value is extremely large.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halogen-free flame-retardant resin composition having both excellent mechanical properties and flame retardancy.

[0002]

2. Description of the Related Art Conventionally, a polyolefin polymer has been widely used as a coating material for electric wires and cables and a resin for connecting materials because it is excellent in electric insulation and workability.
Since it has the drawback of being flammable, various studies have been made on its flame retardancy. Conventionally, it has been general to add a halogen-based flame retardant as a technique for making a resin composition flame-retardant because it is highly effective. However, halogen-based flame retardants have a problem that they emit smoke when burned and generate toxic or corrosive hydrogen halide gas. Therefore, development of non-halogen flame retardant technology for resin compositions has been actively conducted in recent years. Has been done in.
As this non-halogen flame-retardant technique, a method has been proposed in which a hydrated metal compound such as magnesium hydroxide is mixed with a polyolefin resin.

[0003]

However, in the case of blending a hydrous metal compound, since the effect of imparting flame retardancy to the resin composition is weak, a relatively large amount must be added to impart high flame retardancy. As a result, the resulting flame-retardant resin composition has the disadvantage that the properties such as tensile strength and cold resistance are significantly reduced. In particular, in the case of a non-crosslinked flame-retardant resin composition that is often used as a sheath material for cables, etc., a crystalline polymer is blended in order to improve the heat resistance of the resin composition. The composition was further reduced in tensile strength and cold resistance. In order to avoid such deterioration of mechanical properties, the use of red phosphorus or silicone rubber, which exerts a synergistic effect when used in combination with a hydrous metal compound in imparting flame retardancy to a resin composition, has been studied. However, red phosphorus has smoke emission and is not preferable for non-halogen purposes. When silicone rubber is added, there is no problem of smoke emission or generation of toxic gas, but the obtained flame retardant resin. There is a new problem that the tensile strength of the composition is significantly reduced.

[0004]

DISCLOSURE OF THE INVENTION In the present invention, as a result of intensive research focusing on these points, a non-halogen flame-retardant resin that retains high flame retardancy and is excellent in mechanical properties. It was possible to develop a composition. That is, the flame-retardant resin composition of the present invention comprises an organosiloxane oil having an amino group in its molecule in 100 parts by weight of a polyolefin polymer component containing 10% by weight or more of a random copolymer of ethylene and an unsaturated organic carboxylic acid. And / or 5 to 30 parts by weight of an organosiloxane resin having an amino group in the molecule,
It is characterized in that magnesium hydroxide is mixed in a proportion of 50 to 200 parts by weight.

The random copolymer of ethylene and unsaturated organic carboxylic acid in the present invention is a random copolymer composed of a binary monomer of ethylene and unsaturated organic carboxylic acid,
Alternatively, in addition to ethylene and an unsaturated organic carboxylic acid, an olefin other than ethylene, or vinyl acetate,
Olefins such as ethyl acrylate and ethyl methacrylate where α-hydrogen of carbon / carbon double bond is partially replaced by ester group or ether group are copolymerized with one or two or more ternary copolymers. Refers to coalescence. The polyolefin polymer includes, for example, polyethylene, polypropylene, poly 1-butene, polyisobutylene, poly 4
-Homopolymer such as methyl-1-pentene, ethylene
Propylene / diene terpolymer, copolymer of two or more olefins such as styrene / ethylene / butylene / styrene block copolymer, olefin such as ethylene / vinyl acetate copolymer, ethylene / ethyl acrylate copolymer And a copolymer of another polymerizable monomer with each other, or a mixture of two or more kinds.

As the polyolefin polymer used in the present invention, from the viewpoint of the tensile strength of the obtained flame-retardant resin composition, a polyolefin polymer having a crystalline melting point of 90 ° C. or less and a large amorphous fraction is used. Further, from the viewpoint of improving heat resistance, it is preferable to use a crystalline polyolefin polymer having a high melting point, and if a crystalline polymer having a melting point of 120 ° C. or higher is used within a range of 20 to 60% by weight, Without significantly reducing the tensile strength of the flame-retardant resin composition obtained,
The heat resistance can be improved.

Further, the organosiloxane oil having an amino group in the molecule is a linear molecule, and the organosiloxane resin having an amino group in the molecule is a molecule partially having a three-dimensional skeleton. Each of them has an amino group at its terminal or side chain.

Organosiloxane oil having an amino group in the molecule and / or having an amino group in the molecule relative to 100 parts by weight of a polyolefin polymer component containing 10% by weight of a random copolymer of ethylene and an unsaturated organic carboxylic acid. Organosiloxane resin content of 5 to 3
0 parts by weight, the amount of magnesium hydroxide compounded is 50 to 2
The reason why the amount is 00 parts by weight is that the blending amount of the organosiloxane oil having an amino group in the molecule and / or the organosiloxane resin having an amino group in the molecule is 5 parts by weight based on 100 parts by weight of the polyolefin polymer component.
Less than 50 parts by weight, the content of magnesium hydroxide is 50
If the amount is less than 1 part by weight, the resulting resin composition has an oxygen index of 2
This is because only flame retardants having a flame retardancy of 5 or less can be obtained.
The amount of the organosiloxane oil having an amino group in the molecule and / or the organosiloxane resin having an amino group in the molecule is more than 30 parts by weight based on 100 parts by weight of the polyolefin polymer component. If the compounding amount of magnesium hydroxide exceeds 200 parts by weight, the resulting resin composition is saturated in the effect of improving flame retardancy, but on the other hand, the mechanical strength is impaired. It is not preferable.

As the magnesium hydroxide,
It is preferable to use a product surface-treated with a silane coupling agent such as aminosilane because the tensile strength can be further improved. Further, the flame-retardant resin composition of the present invention, if necessary, other additives,
For example, an inorganic filler, a colorant, an antioxidant or the like can be added, and its heat resistance is improved by applying chemical crosslinking using an organic peroxide or the like, or irradiation crosslinking using ionizing radiation. You can also

[0010]

In the flame-retardant resin composition of the present invention, the flame-retardant property is improved by blending an organosiloxane oil having an amino group in the molecule and / or a silicon compound such as an organosiloxane resin having an amino group in the molecule. , A crosslinked structure is formed by the reaction of the carboxylic acid group in the random copolymer of ethylene and the unsaturated organic carboxylic acid used with the amino group in the silicon compound and the improvement in the tensile property by preventing intermolecular slippage. Is obtained.

[0011]

EXAMPLES The working effects of the flame-retardant resin composition of the present invention will be described below with reference to specific examples. Examples 1 to 9 Each blending component was weighed at the composition ratio shown in Table 1, and this was mixed and kneaded by a roll mill at a temperature of 150 ° C to prepare pellets of a flame-retardant resin composition. Next, a sheet-shaped sample was prepared by hot pressing using each of the prepared flame-retardant resin composition pellets, and a tensile test, an oxygen index measurement test according to JIS K7201 and a heat deformation were performed using this sheet-shaped sample. The test was conducted. The test results obtained are also shown in Table 1.

[0012]

[Table 1]

Comparative Examples 1 to 6 Each blending component was weighed at the compositional ratio shown in Table 2, and this was mixed and kneaded by a roll mill at a temperature of 150 ° C. to prepare pellets of a flame retardant resin composition. Next, a sheet-like sample was prepared by hot pressing using each of the prepared flame-retardant resin composition pellets, and the sheet-like sample was used for a tensile test, an oxygen index measurement test according to JIS K7201, and a heat deformation. The test was conducted. The test results obtained are also shown in Table 2.

[0014]

[Table 2]

As is clear from Table 1, the flame-retardant resin compositions of the present invention of Examples 1 to 7 are all 1.3 to 1.8k.
It had a high tensile strength of g / mm ² and a high oxygen index of 27 to 33, which represents flame retardancy.
The flame-retardant resin composition of Examples 2 and 8 containing 40 parts by weight and 50 parts by weight of high-density polyethylene, which is a crystalline polymer having a melting point of 120 ° C. or higher, as a part of the polyolefin polymer component. The product has a slightly low tensile strength of 1.2 to 1.3 kg / mm ² , but the flame-retardant resin composition of Example 9 containing 50 parts by weight of polypropylene has a tensile strength of 1.6 kg / mm ^2. It was high. Also, the oxygen index representing flame retardancy is 29,
The heat deformation rate was as small as 8 to 12%, and high heat resistance was maintained.

On the other hand, as is clear from Table 2,
The base resin has the same constitution as that of the present invention, but the flame-retardant resin compositions of Comparative Examples 1 and 2 using a silicon compound having no amino group in the molecule as the silicon compound have a tensile strength of 0. It is as low as 9 to 1.0 kg / mm ² , has an oxygen index of 27 representing flame retardancy, and has a heating deformation rate of 35.
% And 80%, and the heat resistance was much lower. Further, the respective flame-retardant resin compositions of Comparative Examples 3, 5 and 6 in which the blending ratio of each component is out of the specified range of the present invention had an oxygen index of 28 to 29 which represents flame retardancy. , Its tensile strength is 0.9-1.0k for all
It was as low as g / mm ² . Further, particularly, the tensile strength of the flame-retardant resin composition of Comparative Example 5 was as small as 40 parts by weight with respect to 100 parts by weight of the polyolefin polymer component as 2.0 kg / mm ² . Although it was high, the oxygen index showing flame retardancy was 23, which was extremely low.

[0017]

The flame-retardant resin composition of the present invention has excellent flame retardancy and mechanical properties, and also has excellent heat resistance, and its practical value is extremely large. .

Claims (2)

[Claims] 1. An organosiloxane oil having an amino group in the molecule and / or an amino group in the molecule is added to 100 parts by weight of a polyolefin polymer component containing 10% by weight or more of a random copolymer of ethylene and an unsaturated organic carboxylic acid. A flame-retardant resin composition comprising 5 to 30 parts by weight of an organosiloxane resin having 5 to 50 parts by weight of magnesium hydroxide. 2. A polyolefin polymer component containing 10% by weight or more of a random copolymer of ethylene and an unsaturated organic carboxylic acid, 10 to 80% by weight of a random copolymer of ethylene and an unsaturated organic carboxylic acid, and a crystalline melting point. 2. The flame-retardant resin according to claim 1, which is a mixture of 20 to 60% by weight of a crystalline polyolefin polymer having a temperature of 120 ° C. or higher and the balance of a low crystalline polyolefin polymer having a crystalline melting point of 90 ° C. or lower. Composition.