KR20050117068A - Flame retartant composition having drip-free and low smoke properties on combustion and the cable using thereof - Google Patents

Abstract

The present invention relates to a flame retardant composition in which a certain amount of a flame retardant or an inorganic substance is added to a composite resin in which an alpha olefin copolymer, which is excellent in electrical properties, has good additive filling, has a low melting temperature, and has a low crystalline polymer mixed with an ethylene copolymer. will be. The present invention is based on 100 parts by weight of the base resin consisting of an ethylene copolymer and an alpha olefin copolymer, 30 to 100 parts by weight of a flame retardant or inorganic or a mixture thereof; 0.1 to 5 parts by weight of antioxidant; 0.5 to 3 parts by weight of the processing aid; 1 to 4 parts by weight of the crosslinking aid; And 1 to 15 parts by weight of a crosslinking agent, which provides a flame retardant composition having excellent low smokeability and no bleeding during combustion.

Description

Flame-retardant composition which does not flow down during combustion and has excellent low smokeability and wire using the same {FLAME RETARTANT COMPOSITION HAVING DRIP-FREE AND LOW SMOKE PROPERTIES ON COMBUSTION AND THE CABLE USING THEREOF}

The present invention relates to a flame-retardant composition that does not flow down during combustion and has excellent low smokeability and an electric wire using the same. More specifically, the present invention relates to an excellent property of electrical properties, good filling of additives, low melting temperature, and low crystalline polymer. It relates to a flame retardant composition in which a certain amount of an inorganic flame retardant and an inorganic substance are added to a composite resin in which a copolymer is mixed with an ethylene copolymer.

In the prior art, ethylene copolymers such as ethylene vinyl acetate, ethylene ethyl acrylate, ethylene methyl acrylate, ethylene butyl acrylate, low density polyethylene, linear low density polyethylene, medium, etc. Polyethylene resins such as density polyethylene and high density polyethylene, and resins such as cloned polyethylene and ethylene propylene rubber, were used alone or in combination to crosslink organic resins with organic peroxides. These insulating materials exhibited excellent electrical insulation and heat resistance properties.

Insulation materials used for power cables and crab cables of ship electric wires exhibit excellent electrical and mechanical properties by using ethylene copolymers having a low copolymer content and polyethylene having a high molecular weight alone or in combination. Among the ethylene copolymers, resins and polyethylenes that do not have a large amount of copolymers are generally crystalline resins and have a certain degree of hardness, so that the surface scratches are small and the tensile strength is high, thereby minimizing damage to the insulator during laying. As described above, the crystalline resin has a high melting temperature and thermal characteristics are improved after crosslinking.

In the prior art, the insulating material using the crystalline resin used increases depending on the content of the crosslinking agent and the crosslinking conditions even when a certain load is applied at a high temperature even after crosslinking. Problems will arise. In order to reduce the deformation at high temperature by increasing the crosslinking density, a large amount of crosslinking agent may be added. As a result, the crosslinking time may be shortened, resulting in scorch during extrusion, resulting in poor appearance and poor mechanical properties. In general, the non-combustible insulation material is rapidly burned when the flame is applied, and the flame is diffused, and the flame is diffused by the drip of the resin during combustion, and a large amount of smoke is generated.

In the prior art, by adding a small amount of halogen flame retardant, flame retardancy can be improved or secured without deteriorating mechanical and heat resistance properties. However, in recent years, since environmental regulations have been intensified, halogenated compounds cannot be used, and metal hydrates such as aluminum hydroxide or magnesium hydroxide and organic flame retardants such as nitrogen and phosphorus may be used. However, when a large amount of flame retardant is added for flame retardancy, mechanical properties such as tensile strength and elongation rate are lowered and extrusion processability is lowered.

In the prior art, insulating materials using crystalline resins such as low density polyethylene and high density polyethylene are strongly adhered to copper and tin plated conductors, making it difficult to peel off during installation. In order to solve this problem, a polyester film or the like is wound on the conductor and an insulating material is extruded.

The present invention has been made to solve the above problems, the present invention is excellent in the electrical properties, the filler of the additive is good, the melting temperature is low, the low crystalline polymer mixed with an alpha olefin copolymer mixed with an ethylene copolymer It is an object of the present invention to provide a flame retardant composition having a low flame retardancy and excellent electrical conductivity without adding a flame retardant or an inorganic substance to the resin and having low flow during combustion.

The object is a flame retardant or inorganic or mixtures thereof for a base resin consisting of an ethylene copolymer and an alpha olefin copolymer; Antioxidants; Processing aids; Crosslinking aids; And it can be made through a flame retardant composition excellent in low smoke and no flow during combustion characterized in that it comprises a crosslinking agent.

In addition, the object can be achieved through a flame-retardant composition excellent in low smoke and no flow during combustion, characterized in that the content of the ethylene copolymer is 30 parts by weight to 70 parts by weight with respect to 100 parts by weight of the base resin.

In addition, the object can be achieved through a flame-retardant composition excellent in low smoke and low flow during combustion, characterized in that the content of the flame retardant or inorganic or mixture thereof is 30 parts by weight to 100 parts by weight with respect to 100 parts by weight of the base resin. .

In addition, the object is 0.1 to 5 parts by weight of antioxidant based on 100 parts by weight of the base resin; 0.5 to 3 parts by weight of the processing aid; 1 to 4 parts by weight of the crosslinking aid; And 1 part by weight to 15 parts by weight of a crosslinking agent, which may be made through a flame retardant composition having excellent low smokeability without burning during combustion.

In addition, the object is that the ethylene copolymer is at least one or more of ethylene vinyl acetate, ethylene ethyl acrylate, ethylene methyl acrylate or ethylene butyl acrylate during combustion, even through a low flame retardant composition excellent in low smokeability Can be done.

In addition, the object is that the ethylene copolymer is at least one or more of ethylene vinyl acetate, ethylene ethyl acrylate, ethylene methyl acrylate or ethylene butyl acrylate during combustion, even through a low flame retardant composition excellent in low smokeability Can be done.

In addition, the object is that the ethylene copolymer flows during combustion, characterized in that the melt index is 0.2 g / 10min to 2 g / 10min and the content of the ethylene copolymer is 12 parts by weight to 33 parts by weight with respect to 100 parts by weight of the base resin. It can also be made through a flame-retardant composition having no lowering and excellent low smokeability.

In addition, the above object can be achieved through the flame retardant composition excellent in low smoke and no flow during combustion, characterized in that the alpha olefin copolymer is 30 parts by weight to 70 parts by weight with respect to 100 parts by weight of the base resin.

In addition, the above object can be achieved through the flame retardant composition excellent in low smoke and no flow during combustion, characterized in that the alpha olefin copolymer is one or more of ethylene butene copolymer, ethylene propylene copolymer, ethylene octene copolymer.

In addition, the object is that the alpha olefin copolymer has a melt index of 0.5 g / 10min to 35g / 10min and the content of 100 parts by weight of the base resin of 12 parts by weight to 33 parts by weight during the combustion, it does not flow down and low smokeability It can also be achieved through this excellent flame retardant composition.

In addition, the purpose of the flame retardant is an average particle diameter of 0.4 ㎛ to 5 ㎛, and the specific target is 3m ² / g to 20 m ² / g during combustion characterized in that even through a flame-retardant composition excellent in low smoke and low smokeability Can be.

In addition, the purpose of the flame retardant is a metal hydroxide surface-treated with a silane is at least one or more of magnesium hydroxide, aluminum hydroxide, magnesium carbonate or zinc borate during the combustion, characterized in that no flow through the flame retardant composition excellent in low smoke Can be done.

In addition, the inorganic agent has an average particle diameter of 0.2 ㎛ to 6 ㎛, specific target is 3m ² / g to 6 m ² / g during the combustion, characterized in that the flame retardant composition excellent in low smoke and low smokeability Can be done.

In addition, the above-mentioned object may be achieved even through a flame retardant composition having excellent low smokeability without burning during combustion, characterized in that at least one of talc or clay surface-treated with silane.

In addition, the object is that the antioxidant is excellent in low smoke and low smoke during combustion, characterized in that containing 0.1 to 5 parts by weight of at least one of phenolic, hindered phenolic, thioester or amine-based It may also be made through a flame retardant composition.

In addition, the object of the processing aid may be achieved through a flame retardant composition excellent in low smoke and no slump during combustion, characterized in that at least one of wax, stearic acid or silicon.

In addition, the object of the processing aid may be made through a flame-retardant composition excellent in low smoke and no flow during combustion, characterized in that the content is 0.5 parts by weight to 3 parts by weight.

In addition, the above object can also be achieved through the electric wire, characterized in that made of the flame retardant composition.

Other objects, specific advantages and novel features of the present invention will become more apparent from the following detailed description and the preferred embodiments associated with the accompanying drawings.

Hereinafter will be described in detail with respect to the flame-retardant composition and the wire using the excellent flame retardancy without flowing during the present invention.

The present invention relates to a polymer resin composition which is an insulating material used for an insulator of a general power cable, has no phenomena during combustion, has low smokeability, and is easily peelable to a conductor. The flame retardant composition according to the present invention comprises a base resin composed of an ethylene copolymer and an alpha olefin copolymer, a flame retardant, an antioxidant, a processing aid, a crosslinking aid and a crosslinking agent. Hereinafter, each of the components of the present invention will be described.

The flame retardant composition according to the present invention uses an ethylene copolymer and an alpha olefin copolymer as the base resin.

Ethylene copolymer is a resin suitable for compound for electric wires because of excellent filling property of flame retardant or inorganic material. The ethylene copolymer has a melt index of 0.2 g / 10min to 2 g / 10min, but when the melt index is less than 0.2 g / 10min, the viscosity is high, so that the extrusion is overloaded. This will affect the appearance of the wires, such as maintaining the prototype.

Ethylene vinyl acetate, ethylene ethyl acrylate, ethylene methyl acrylate, ethylene butyl acrylate and the like are used as the ethylene copolymer, and the content of the copolymer in the ethylene copolymer is 12 parts by weight to 33 parts by weight based on 100 parts by weight of the ethylene copolymer. Preference is given to using parts by weight. When the content of the copolymer in the ethylene copolymer is 12 parts by weight or less, the crystallinity is high, the low temperature property is lowered, the hardness is increased, the flexibility is decreased, and it is difficult to fill a large amount of flame retardant. When the content of the copolymer in the ethylene copolymer is 33 parts by weight or more, the flame retardant filling property is excellent, but mechanical properties such as tensile strength are lowered.

The alpha olefin copolymer is characterized by excellent flexibility, light weight, and low temperature characteristics, and a melt index of 0.5 g / 10 min to 35 g / 10 min is used. If the melt index is less than 0.5g / 10min, the viscosity is high, the overload is extruded, and if the melt index is more than 35g / 10min, the viscosity is low, affecting the appearance of the wire, such as maintaining the circular shape during extrusion.

As the alpha olefin copolymer, an ethylene butene copolymer, an ethylene propylene copolymer, an ethylene octene copolymer, or the like is used. The content of the propylene copolymer, butene copolymer, octene copolymer, etc. is 12 weight based on 100 parts by weight of the alpha olefin copolymer. Part to 33 parts by weight is preferable. If the content of the propylene copolymer, butene copolymer, octene copolymer, etc. is less than 12 parts by weight with respect to 100 parts by weight of the alpha olefin copolymer, the crystallinity is increased and the flexibility is inferior. It is lowered, the extrudability is lowered, and mechanical properties such as tensile strength are lowered.

As the base resin of the flame retardant composition according to the present invention, 100 parts by weight of 30 parts by weight to 70 parts by weight of the ethylene copolymer and the ethylene alpha copolymer are used. When using 70 parts by weight or more of the ethylene copolymer and 30 parts by weight or less of the alpha olefin copolymer in the base resin, there is a disadvantage in that the flow phenomenon occurs during combustion or the properties at low temperatures are deteriorated. On the contrary, when the ethylene copolymer is used in an amount of 30 parts by weight or less and the alpha olefin copolymer is used in an amount of 70 parts by weight or more, the crystallinity is lowered, resulting in poor mechanical properties.

The present invention uses a flame retardant to improve flame retardancy and to improve insulation. As the flame retardant, inorganic flame retardants such as metal hydroxides are preferably used. In order to impart flame retardancy to the flame retardant composition according to the present invention and to improve oil resistance and tear strength properties, a metal hydroxide surface-treated with silane is used. It is preferable to use at least one of magnesium hydroxide, aluminum hydroxide, magnesium hydroxide carbonate, zinc borate and the like for the metal hydroxide surface-treated with silane. Typically, the average particle size of the flame retardant is 0.4 µm to 5 µm, and the specific target (BET) is preferably 3 m ² / g to 20 m ² / g.

In the present invention, an inorganic material may be used instead of the flame retardant. Inorganic materials have an effect of improving the tensile strength and tear strength properties with the improvement of flame retardancy. As the inorganic substance, at least one of talc or clay surface-treated with silane is preferably used. Usually, the average particle diameter of the inorganic material is preferably 0.2 µm to 6 µm and the specific target (BET) is 3 m ² / g to 6 m ² / g.

When used by mixing the flame retardant and inorganic described above, because of the synergistic effect of the flame retardancy and tensile strength, tear strength and the like is further improved in the present invention, it is more preferable to use a mixture of the flame retardant and inorganic. The content of the flame retardant or the inorganic substance or mixtures thereof is preferably 30 parts by weight to 100 parts by weight. If the flame retardant or inorganic material or mixture thereof is 30 parts by weight or less, the flame retardancy and low smoke resistance is inferior. If it is 100 parts by weight or more, the flame retardancy is excellent, but mechanical properties such as tensile strength and elongation rate are remarkably inferior.

In the present invention, an antioxidant is used. As the antioxidant, a phenol-based, hindered phenol-based, thioester-based, or amine-based may be used to prevent aging of the insulating material due to long-term use. As the antioxidant, 0.1 to 5 parts by weight of the hindered phenol-based antioxidant may be used. Preferably 0.5 to 1.5 parts by weight was applied.

In the present invention, it is preferable to use a processing aid. Higher fatty acids, fatty acid amir compounds, stearic acid, waxes, silicones and the like can be used as processing aids. Specifically, the processing aid may use 0.5 parts by weight to 3 parts by weight of polyethylene wax to secure thermal stability, and 0.5 parts by weight to 3 parts by weight of stearic acid consisting of a nonpolar long aliphatic hydrocarbon and a few polar groups as an external processing aid. Can be.

In this invention, it is preferable to use a crosslinking adjuvant in order to raise crosslinking density. The crosslinking aid is preferably at least one of trially isocyanate or trimethylolpropane trimethacrylate. In addition, the content of the crosslinking aid is generally preferably used 1 part by weight to 15 parts by weight.

The flame-retardant composition according to the present invention is preferably chemically cross-linked and organic peroxides are used as crosslinking agents in order to satisfy thermal properties and mechanical properties required in electric wire materials. Such organic peroxides preferably use organic peroxides contained in various carriers. In particular, it is preferable to use 2 parts by weight to 10 parts by weight of di-2tert butyl peroxyisopropyl benzene (Di- (2-tert.-butyl-peroxyisopropyl) -benzene) to which silica is applied as a carrier. It is preferable to use 1 to 4 parts by weight of trimethylolpropane trimethacrylate, triallyl isocyanurate, polybutadiene, etc. in order to increase the crosslinking density and reduce the heat deformation properties. It is also preferable to use 50% to 70% of triallyocyanurate for the crosslinking agent.

The flame retardant composition which does not flow during combustion according to the present invention and has excellent low smokeability, and the electric wire using the same are prepared through the composition consisting of a mixture of the flame retardant and the inorganic material, the antioxidant, the processing aid, the crosslinking aid, and the crosslinking agent. It is possible to obtain excellent properties, good filling properties of additives, low melting temperature, low crystalline polymer composition and wires using the same.

Hereinafter, a flame retardant composition having no flow-down during combustion according to the present invention and excellent flame retardancy and an electric wire using the same will be described in more detail with reference to preferred examples and comparative examples.

In the present invention, the ethylene alpha olefin copolymer having low melting temperature and low crystallinity and an inorganic flame retardant and an inorganic material surface-treated with silane are applied to the ethylene copolymer instead of polyethylene, which is mainly used in the insulation material of the prior art, and is melted and melted during combustion. The embodiment to eliminate the phenomenon and have a low smokeability is shown in Table 1 below.

Formulation Name Example 1 Example 2 Example 3 Example 4 Example 5 Ethylene vinyl acetate ¹⁾ 50 50 50 30 50 Alpha olefin copolymer 50 50 50 70 50 Antioxidant 1.5 1.5 1.5 1.5 1.5 Processing aid One One One One One Magnesium Hydroxide (Silane Surface Treatment) 60 Talc (silane surface treatment) 60 60 80 Clay (Silane Surface Treatment) 60 Crosslinking agent 2 2 2 2 2 Crosslinking aid 4 4 4 4 4 Test Items Exam conditions unit The tensile strength 250 mm / min kgf / mm ² 1.87 2.47 1.59 2.33 1.76 Elongation % 340 458 310 486 387 Tensile residual rate 121 ℃ 168 hours % 94 98 101 94 96 Elongation % 96 99 94 100 92 Acting index NES 711 SI 46.2 35.6 38.4 55 38 Stripping pass pass pass pass pass Crosslinking 150 ° C., 15 minutes % 2.5 2.5 5 5 5 Volume resistance Ωcm (× 10 ¹⁴ ) 3.2513 4.8867 3.8275 6.6218 5.3126

1) Ethylene vinyl acetate with a vinyl acetate content of 19 parts by weight

As the base resin of the insulating material, medium-density polyethylene, low-density polyethylene, or linear low-density polyethylene with high crystallinity and high melting temperature has been conventionally used. Such non-polar crystalline polymer resins have limitations in the filling of organic and inorganic additives, making it difficult to fill excess organic and inorganic additives, and thus have disadvantages of flame retardancy, mechanical properties, and high smokeability during combustion. A comparative example of such a prior art is shown in Table 2 below.

Formulation Name Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Ethylene vinyl acetate ¹⁾ 50 50 50 50 Low density polyethylene 50 50 50 50 Antioxidant 1.5 1.5 1.5 1.5 Processing aid One One One One Magnesium hydroxide 60 Talc 60 80 Clay 60 Crosslinking agent 2 2 2 2 Crosslinking aid 4 4 4 4 Test Items Exam conditions unit The tensile strength 250 mm / min kgf / mm ² 1.91 1.59 1.13 1.35 Elongation % 481 290 250 279 Tensile residual rate 121 ℃ 168 hours % 100 102 118 100 Elongation % 85 90 89 81 Acting index NES 711 SI 110 88 84.7 94 Stripping fail fail fail fail Crosslinking 150 ° C., 15 minutes % 20 20 200 20 Volume resistance Ωcm (× 10 ¹⁴ ) 1.3441 1.06 2.0427 2.8102

1) Ethylene vinyl acetate with a vinyl acetate content of 9 parts by weight

Tensile strength and elongation were tested according to ASTM D638.

The smoke index was tested according to NES711.

Crosslinking was tested according to IECA T-28-562.

Peelability determined that the insulator stripped did not deform when the cable was produced and stripped with the stripper.

The present invention has been described in more detail by describing preferred embodiments and comparative examples. However, the scope of the present invention is not limited to the above embodiments but may be embodied in various forms of embodiments within the appended claims. Without departing from the gist of the invention as claimed in the claims, any person of ordinary skill in the art is considered to be within the scope of the claims described in the present invention to the extent possible to vary.

The present invention provides excellent electrical properties, good filling properties of additives, low melting temperature, low crystalline polymer, and the addition of a certain amount of inorganic flame retardant and inorganic material to the composite resin mixed with the ethylene copolymer. It provides a flame-retardant composition having no falling and excellent in low smoke, and a wire having such an effect.

Although the invention has been described with reference to the preferred embodiments mentioned above, many other possible modifications and variations can be made without departing from the spirit and scope of the invention. Accordingly, the appended claims are intended to cover such modifications and variations as fall within the true scope of the invention.

Claims (14)

Regarding the base resin consisting of an ethylene copolymer and an alpha olefin copolymer, Any one or mixtures thereof selected from flame retardants and inorganics; Antioxidants; Processing aids; Crosslinking aids; And A flame retardant composition excellent in low smokeability without flowing down during combustion, comprising a crosslinking agent. The flame retardant composition of claim 1, wherein the content of the ethylene copolymer is 30 parts by weight to 70 parts by weight with respect to 100 parts by weight of the base resin. The flame retardant composition of claim 1, wherein the content of the flame retardant or the inorganic substance or the mixture thereof is 30 parts by weight to 100 parts by weight with respect to 100 parts by weight of the base resin. According to claim 1, with respect to 100 parts by weight of the base resin, 0.1 to 5 parts by weight of antioxidant; 0.5 to 3 parts by weight of the processing aid; 1 to 4 parts by weight of the crosslinking aid; And 1 to 15 parts by weight of the crosslinking agent, characterized in that the flame-retardant composition excellent in low smoke and low flow during combustion . The flame retardant composition of claim 1, wherein the ethylene copolymer is at least one of ethylene vinyl acetate, ethylene ethyl acrylate, ethylene methyl acrylate, and ethylene butyl acrylate. The combustion of claim 1, wherein the ethylene copolymer has a melt index of 0.2 g / 10 min to 2 g / 10 min and a content of the ethylene copolymer is 12 parts by weight to 33 parts by weight based on 100 parts by weight of the base resin. Flame-retardant composition that does not run off and has excellent low smokeability. The flame retardant composition of claim 1, wherein the alpha olefin copolymer is 30 parts by weight to 70 parts by weight with respect to 100 parts by weight of the base resin. The flame retardant composition of claim 1, wherein the alpha olefin copolymer is at least one of an ethylene butene copolymer, an ethylene propylene copolymer, and an ethylene octene copolymer. According to claim 1, wherein the alpha olefin copolymer has a melt index of 0.5 g / 10min to 35g / 10min and the content of 100 parts by weight of the base resin of 12 parts by weight to 33 parts by weight without burning down during combustion, characterized in that Flame retardant composition excellent in low smoke. The flame retardant composition of claim 1, wherein the flame retardant is a metal hydroxide surface-treated with silane and is at least one of magnesium hydroxide, aluminum hydroxide, magnesium carbonate, and zinc borate. The flame retardant composition of claim 1, wherein the inorganic agent is at least one of talc or clay surface-treated with silane. The method of claim 1, wherein the antioxidant is at least one or more of the phenolic, hindered phenolic, thioester or amine-based 0.1 to 5 parts by weight of the non-flowing during combustion, low smokeability This excellent flame retardant composition. The flame retardant composition of claim 1, wherein the processing aid is at least one of wax, stearic acid, or silicone. An electric wire made of the flame retardant composition according to any one of claims 1 to 14.