KR100199052B1 - Flame retardant polyolefin compound having low smoking and toxicity - Google Patents

Abstract

60 to 150 parts by weight of a flame retardant component added with 1 to 20 parts by weight of carbon fine powder based on 100 parts by weight of the composite metal hydroxide represented by the general formula Mg _1-x M ²⁺ _x (OH) ₂ with respect to 100 parts by weight of the polyolefin resin. A low-flammability-low-toxic flame-retardant polyolefin compound characterized by being added, wherein M ²⁺ is a divalent metal ion of Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ²⁺ and Zn ²⁺ . It is at least 1 sort (s) selected from the group of, and X is a number which satisfy | fills 0.001 <= X <= 0.9.

Description

Low flame and low toxicity flame retardant polyolefin compounds

TECHNICAL FIELD The present invention relates to a low smoke and low toxicity flame retardant material used as a low smoke and low toxicity polyolefin compound, in particular as an electric wire and cable coating material or various electrical component materials.

Polyolefin resins generally have flexibility, are excellent in electrical insulation, and are inexpensive compared to other materials, and thus are widely used in wire coating materials and various electric component materials. By the way, regarding wire covering materials and various electric component materials, the demand for flame retardation has increased and became severe in the event of a serious fire accident which occurred in the past.

In order to meet the demand of flame retardant, flame retardants using an organic halogen compound and antimony trioxide in combination have been proposed and implemented, but the flame retardant material by these combinations partially decomposes during processing to generate halogen gas, Not only does it corrode processing machines and molding machines, but it is also toxic to workers. In addition, when a fire occurs, there is a problem of generating a large amount of smoke containing toxic gas. For this reason, in consideration of safety in manufacturing and use, the demand for a non-halogen-based flame retardant has increased, and metal hydroxides have attracted attention.

However, aluminum hydroxide, which is a typical metal hydroxide, has a problem that the resin to be applied is limited because dehydration starts from about 190 ° C. and problems due to foaming occur in the molded article.

On the other hand, since magnesium hydroxide has a high decomposition temperature and almost no application resin, it has been applied to wire coating materials and various electric component materials as non-halogen flame retardant compound materials.

By the way, polyolefin resins are generally easy to burn, and in order to be flame retardant, it is necessary to add magnesium hydroxide in large quantities, and thus practical problems such as deterioration of the original resin properties and a significant drop in mechanical properties and workability. There were a lot.

In order to solve these problems, in the polyolefin resin material containing no halogen, flame retardant aids such as red powder and fine carbon powder are added to reduce the amount of hydroxide added as much as possible. Attempts have been made. However, the red has a problem that care must be taken in handling during processing, and that the addition of fine carbon powder reduces the compounding amount to the level of REBE that satisfies the mechanical properties, and thus the effect as a flame retardant aid is not recognized.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and in the polyolefin resin material containing no halogen, the addition of flame retardant materials, particularly hydroxides, can be reduced as much as possible, and mechanical properties are improved and flame retardancy is improved. An object of the present invention is to provide a flame retardant polyolefin-based compound suitable as a secured wire covering material and an electric component material.

As a result of intensive studies, the present inventors have used the composite metal hydroxide and the fine carbon powder as a flame retardant, so that the amount of the flame retardant component can be significantly reduced in the polyolefin resin, thereby securing necessary flame retardancy. At the same time, a flame retardant polyolefin compound with sufficient mechanical properties was found.

That is, the low-flammability, low-toxic flame-retardant polyolefin compound of the present invention comprises a flame retardant component in which 1 to 20 parts by weight of carbon fine powder is added to 100 parts by weight of polyolefin resin and 100 parts by weight of the composite metal hydroxide represented by the following formula (1). It contains to 60 to 150 weight part specifically.

In the formula, M ²⁺ is at least one selected from the group of divalent metal ions of Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ^2+, and Zn ²⁺ , and X is 0.001 ≦ X A number satisfying ≤0.9.

As the polyolefin resin, polyethylene, polypropylene, ethylene-ethyl acrylate copolymer and the like are used, but polyethylene is particularly suitable in terms of flame retardancy and mechanical properties.

As mentioned above, the flame-retardant component of this invention adds 1 to 20 weight part of carbon fine powders with respect to 100 weight part of composite metal hydroxides represented by Formula (1).

It is dispersed in the above fine carbon powder and polyolefin resin, and acts like a carbon-forming epitaxial substrate at the time of combustion, and efficiently expresses the carbonization catalyst effect of the transition metal dissolved in the composite metal hydroxide. As a result, the carbonization of the resin is greatly improved.

Therefore, since it is possible to achieve the required flame retardant by a small amount of flame retardant, it is possible to improve the physical properties, ie mechanical properties of the compound.

The amount of the flame-retardant component added to the resin is 60 to 150 parts by weight based on 100 parts by weight of the resin. If it is less than 60 parts by weight, the flame retardant effect is insufficient, and if it exceeds 150 parts by weight, the processability of the compound and the mechanical properties of the product are significantly reduced. More preferably, it exists in the range of 80-150 weight part.

That is, when used as an electric wire coating material or an electric component, as a standard of mechanical strength, as these plastic materials, it is preferable that tensile strength is 1 Kg / mm <2> or more and the elongation is 500% or more. When it is below these strengths, handling of a product becomes difficult practically.

In addition, as mentioned above, the flame-retardant component in this invention adds 1-20 weight part of carbon fine powders with respect to 100 weight part of composite metal hydroxides. If the added amount of the fine carbon powder is less than 1 part by weight, sufficient flame retardant effect cannot be obtained, and if it is more than 20 parts by weight, the physical properties are inferior. Preferably, the range of 1-15 weight part is preferable.

By using a combination of the composite metal hydroxide as the flame retardant component and the carbon fine powder with respect to the polyolefin resin, the flame retardancy of the polyolefin compound can be greatly improved, and low smoke and low toxicity can be achieved. It is also possible to improve the mechanical properties of the compound.

EXAMPLE

EMBODIMENT OF THE INVENTION Below, this invention is demonstrated in detail with reference to an Example.

[Examples 1-3]

As the material provided for the test, 0.2 parts by weight of an antioxidant and 100 parts by weight of low-density linear polyethylene (hereinafter referred to as LLDPE) were used as the flame retardant component, Mg _0.98 Ni _0.02 (OH) ₂ and Mg _0.95 Zn _0.05 (OH) ₂ and fine carbon powder were mixed by blender with the amounts shown in Table 1, and then kneaded at 130 ° C. in a biaxial roll, and then press-molded at 160 ° C. to form a 1 mm thick sheet and about 3.2 mm thick. The sheet was molded and punched into a dumbbell shape and a rectangular shape, respectively, to obtain a test sample. These samples were subjected to a tensile test in accordance with JIS C 3005 and a combustion test in accordance with UL 94VE.

[Comparative Examples 1-4]

As the comparative sample, magnesium hydroxide Mg (OH) ₂ was used in place of the composite metal hydroxide constituting the flame retardant component in Examples 1 to 3, and the sample shown in Table 1 was prepared in the same manner as in Examples 1 to 3 Was written and tested.

The test results are shown in Table 2.

As apparent from Table 2, it was found that when a flame retardant component composed of the composite metal hydroxide and the carbon fine powder represented by the formula (1) was used, the flame retardancy was greatly improved and the mechanical strength also reached the practical level.

On the contrary, in the comparative example in which the metal hydroxide was used in combination with the fine carbon powder instead of the composite metal hydroxide, in the case where the addition amount of the metal hydroxide was the same level as the metal hydroxide as in Examples 1 to 3, as in Comparative Examples 1 to 3, The required flame retardancy could not be obtained.

In addition, as in Comparative Example 4, in order to impart flame retardancy, when 120 parts by weight of metal hydroxide was added, the required flame retardancy was obtained, but as mechanical properties, the tensile strength was 0.91 Kg / mm 2, and the required strength was 498%. Could not be held and became practically impaired.

By adding a prescribed amount of a flame retardant component composed of a composite metal hydroxide and a fine carbon powder to a polyolefin resin containing no halogen, sufficient flame retardancy can be achieved even if the amount is less than the amount of the conventional metal hydroxide, and also low smoke and low toxicity It became possible to achieve this. It has become possible to greatly reduce the amount of metal hydroxide and to significantly prevent deterioration of mechanical properties due to the large amount of hydroxide addition.

Claims (5)

60 to 150 parts by weight of a flame retardant component added with 1 to 20 parts by weight of fine carbon powder based on 100 parts by weight of the composite metal hydroxide represented by the general formula Mg _1-x M ²⁺ _x (OH) ₂ with respect to 100 parts by weight of the polyolefin resin. A low smoke and low toxicity flame retardant polyolefin compound, which is prepared by addition. [ ^Wherein M ²⁺ is at least one member selected from the group of divalent metal ions of Mn ²⁺ , Fe ²⁺ , Co ²⁺ , Ni ²⁺ , Cu ²⁺ and Zn ²⁺ , and X is 0.001 ≦ X Is a number satisfying ≤0.9] The low-flammability and low-toxic flame retardant polyolefin compound according to claim 1, wherein the divalent metal ion M ²⁺ is at least one member selected from the group of Ni ²⁺ and Zn ²⁺ . The low flame retardant and low toxicity flame retardant polyolefin compound according to claim 1 or 2, wherein the flame retardant component is added by adding 80 to 130 parts by weight. The low-flammability and low-toxic flame retardant polyolefin compound according to claim 1 or 2, wherein the carbon fine powder is added in an amount of 1 to 15 parts by weight based on 100 parts by weight of the composite metal hydroxide. The low-flammability and low toxicity flame retardant polyolefin according to claim 1 or 2, wherein the polyolefin resin comprises at least one member selected from polyethylene, polypropylene, ethylene-ethyl acrylate copolymer and ethylene-vinyl acetate copolymer. compound.