KR100624878B1 - Composition and method for production flame retardant insulating material of halogen free type with high voltage cut-through test - Google Patents

Abstract

The present invention relates to a composition for producing a non-halogen flame retardant insulating material having a cut-through property and a method for producing a non-halogen flame-retardant insulating material having a cut-through property using the same. The composition for producing a non-halogen flame-retardant insulating material having a cut-through property according to the present invention, 100 parts by weight of a polyolefin resin that is a base resin; 110 to 300 parts by weight of a metal hydroxide of an inorganic flame retardant; 5 to 100 parts by weight of zinc borate which is a flame retardant aid; 0.5 to 20 parts by weight of fatty acid processing aid; 0.5 to 20 parts by weight of tartaric acid processing aid; And 0.5 to 5 parts by weight of antioxidant; characterized in that consisting of. According to the present invention, since the halogen element is not included in the composition composition used, it can be said to be more environmentally friendly than conventional halogen-based products during combustion, and it is possible to secure the flame retardancy required by the high flame retardant grade VW-1. In addition, it is possible to meet the cut-through characteristics to improve the productability, and in the case of using as an insulating material, in particular, an insulating coating layer for electric wire, it is preferable because the physical properties such as the required tensile strength and elongation can be secured well.

Cut-through, flame retardant, zinc borate, metal hydroxide, crosslinking

Description

Composition for manufacturing non-halogen flame retardant insulating material having cut-through characteristics and method for producing non-halogen flame retardant insulating material having cut-through characteristics {Composition and method for production flame retardant insulating material of halogen free type with high voltage cut-through test}

The present invention relates to a composition for producing a non-halogen flame-retardant insulating material having a cut-through property, and more specifically, to maintain the crystallinity less than 50% to ensure a modulus ratio of 75% or more according to the temperature to be a damage factor of the insulating material The present invention relates to a composition for producing a non-halogen flame retardant insulating material capable of securing resistance to cut through.

Thermoplastic resins such as polyethylene, which are conventionally used as a flame retardant insulating material, are organic materials composed of combustible materials such as hydrogen and carbon due to their chemical structure, and have a high smoke concentration at the time of fire. In addition, when a fire occurs, a large amount of smoke containing toxic gas is generated, causing secondary casualties and the like.

In order to be used as an insulating material for electric wires, a flame retardance of a certain degree or more is required, and a method of using a resin composition containing a halogen element is known that has been developed for the purpose of improving the flame retardancy. On the other hand, in the case of an insulating material manufactured using a resin composition containing a halogen element, it is known to suppress the combustion of materials by generating a non-flammable heavy halogen gas during combustion and forming a solidified ash by reacting with an additive. Therefore, in the case of the insulating material manufactured using a halogen-based resin, flame retardancy is basically retained, and various flame retardants are added for the purpose of further improving flame retardancy. The various flame retardants added in this way does not significantly affect the basic physical properties of the base resin, and does not cause an increase in the viscosity of the insulating material, and thus has an advantage of expressing excellent extrusion processability. On the other hand, compared to the case where the polar resin used alone is difficult to secure the physical properties required as an insulating material, a method of mixing different polar resins having physical and chemical affinity are becoming common. Specifically, polar resins containing chlorine, which is a halogen element, are used in a resin composition for producing an insulating material used as a conventional insulating coating layer for electric wires. Chlorinated polyethylene, polyvinyl chloride, etc. are used for this polar resin. In addition, a resin in which vinyl chloride is bonded to ethylene vinyl acrylate and chlorinated polyethylene may be used in combination. In the prior art, by adjusting the content of the copolymer such as ethylene vinyl acetate copolymer, ethylene ethyl acrylate copolymer appropriately and mixed with polyethylene to improve the electrical properties, heat resistance, heat deformation characteristics and the like.

When an insulating material is used as an insulating coating layer of an electric wire, damage occurs to the insulating material when contact with a metal piece of a sharp blade applied from the outside occurs. This phenomenon is called 'cut-through'. Research has been done in parallel.

In order to manufacture a conventional insulation coating layer for electric wires, a high-density polyethylene and an ethylene copolymer having high melting temperature, crystallinity, and the like have been used. In this regard, for an electric wire coated with an insulating material manufactured using a conventional halogen-based resin, it is prevented from being deformed by a certain load at a high temperature and crosslinked using an electron beam in the manufacturing process for the purpose of preventing cut-through. We are going to make a step. However, when the electron beam is irradiated for the purpose of crosslinking, the halogen element contained in the base resin is decomposed, and thus, the heat resistance is significantly lowered, and thus, the heat deformation and the cut through properties are deteriorated. In particular, if the electron beam is excessively irradiated to increase the crosslinking density of the base resin for the purpose of enhancing the heat resistance property, mechanical properties such as elongation rate are drastically lowered, and the decomposition of the base resin is accelerated during the exposure to the electron beam, thereby significantly reducing the heat deformation. When the base resin is exposed to the electron beam for a long time at a specific temperature, it has an extremely low elongation, which is not preferable. In order to compensate for this, it is also possible to consider adding an additive to enhance the properties, but it is expected that problems may change the physical properties of the base resin. As a result, the insulating material produced by using a conventional halogen-based resin has a problem that the flame retardancy is lowered.

In addition, halogen-based flame retardant insulation materials containing bromine (Br) and chlorine (Cl) components, which are halogen elements, have been confirmed to cause various problems that threaten the human body or the environment in the manufacturing process or use thereof. Due to the problem of emitting toxic gases such as dioxins, research has been conducted on flame-retardant insulating materials containing no halogen element from an environmentally friendly point of view.

As described above, as a highly flame-retardant insulating material that does not contain a halogen element, a study on the development of a material for manufacturing a new type of insulating material in which the cut-through characteristics should be improved and the required mechanical properties of the product can be maintained Has been made consistently in the related art, the present invention has been devised under this technical background.

Technical problem to be solved by the present invention based on the above-mentioned conventional problems, using a resin composition that does not contain a halogen element in the insulating material, should be able to suppress or prevent cut-through, product manufactured using the insulating material In order to ensure the various physical properties required in the present invention, and a composition for producing a non-halogen flame-retardant insulating material having a cut-through characteristic that can achieve such a technical problem and a method for producing a non-halogen flame-retardant insulating material having a cut-through characteristic using the same. It is an object of the present invention to provide.

In order to achieve the technical problem to be achieved by the present invention, the composition for producing a non-halogen flame-retardant insulating material having a cut-through property according to the present invention, 100 parts by weight of a polyolefin-based resin of the base resin; Parts by weight; 5 to 100 parts by weight of zinc borate which is a flame retardant aid; 0.5 to 20 parts by weight of fatty acid processing aid; 0.5 to 20 parts by weight of tartaric acid processing aid; And 0.5 to 5 parts by weight of antioxidant; characterized in that consisting of.

The base resin polyolefin resin is any one selected from ethylene copolymers consisting of ethylene vinyl acetate (EVA), ethylene ethyl acrylate (EEA), ethylene butyl acrylate (EBA) and ethylene methyl acrylate (EMA) or 5 to 80 parts by weight of a mixture of two or more; 5 to 20 parts by weight of the modified polyolefin resin; And ethylene propylene rubber (EPR) comprising 0 to 80 parts by weight.

In this case, with respect to the content of the ethylenic copolymer constituting a part of the base resin, when the lower limit of the numerical limit is less than, the tensile strength or elongation at room temperature is lowered due to the flame retardant filler lowering, the numerical limit If the upper limit is exceeded, electrical insulation is deteriorated due to a decrease in volume resistance, which is undesirable.

On the other hand, ethylene propylene rubber (EPR) constituting a part of the base resin may not be included in the base resin at all, when used in excess of the upper limit of the numerical limit is not preferable because the high temperature modulus occurs. In addition, when the content of the modified polyolefin resin constituting a part of the base resin is less than the lower limit of the numerical limit, the coupling effect between the resin and the flame retardant is small, resulting in a decrease in elongation and tensile strength. When the upper limit of the limit is exceeded, a problem that the elongation rate is lowered due to excessive coupling effect is not preferable.

The modified polyolefin resin is preferably one having two or more selected from polyethylene (PE), high density polyethylene (HDPE), ethylene vinyl acetate (EVA), and linear low density polyethylene (LLDPE).

The metal hydroxide which is the inorganic flame retardant is preferably any one selected from magnesium hydroxide (Mg (OH) ₂ ) and aluminum hydroxide (Al (OH) ₃ ) or a mixture of the two. At this time, with respect to the content of the metal hydroxide which is the inorganic flame retardant, the flame retardancy is lowered when the numerical limits are not exceeded, and when the numerical limits are exceeded, mechanical properties such as elongation and tensile strength of the product are lowered, which is not preferable. Can not do it.

Zinc borate, a flame retardant aid, serves to facilitate the formation of a char that improves flame retardancy by forming a solid film during combustion, and in relation to its content, flame retardancy is lowered if it is less than the numerical limit. When the numerical limit is exceeded, the mechanical properties are lowered, which is not preferable.

The fatty acid-based processing aid and tartaric acid-based processing aid may exhibit an additive effect only when the lower limit of the numerical limit is included in the composition. When the fatty acid-based processing aid exceeds the upper limit of the numerical limit, the additive is not uniformly dispersed, which is not preferable. . Calcium stearate is used as the fatty acid processing aid, and zinc stannate or calcium stannate is used as the tartaric acid processing aid.

With respect to the antioxidant, when the numerical limit is not reached, the original additive effect related to the antioxidant cannot be expressed, and when the numerical limit is exceeded, the blooming or bleed out effect occurs, which is not preferable.

In order for the flame retardant insulating material manufactured using the above-described composition to have cut-through characteristics, the ratio between high modulus and room temperature modulus becomes an important factor, and its crystallinity must be less than 50% so that the modulus ratio according to temperature is 75% or more. This can be secured. Therefore, the flame-retardant insulating material manufactured using the above-described composition is preferably such that the modulus at 105 ° C. (high temperature) is at least 10 kgf / mm 2, and the modulus at 105 ° C. is 75% or more relative to the modulus at room temperature. On the other hand, the insulating material prepared according to the present invention is preferable if the insulation resistance at room temperature (25 ℃) is ensured more than 300M Ω / km.

In order to achieve the technical problem to be achieved by the present invention, in the method for producing an insulating material using a composition for producing a non-halogen flame-retardant insulating material having a cut-through property according to the present invention, the resin crosslinking in the composition for preparing the insulating material is a crosslinking method, a chemist It is characterized by proceeding by any one method selected from the teaching method and the investigation bridge method.

The above-described composition for producing a non-halogen flame retardant insulating material and a method for producing a non-halogen flame retardant insulating material using the same are preferably used to prepare an insulating coating layer for a non-halogen flame retardant wire having cut-through characteristics.

Hereinafter, the present invention will be described with reference to Examples. However, embodiments according to the present invention can be modified in many different forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art.

Classification of Example (1-7) and Comparative Example (1-4)

As examples according to the present invention, the divisions were set as Examples 1 to 7 (see Table 1 below), and Comparative Examples 1 to 4 (see Table 2 below) were set as the purpose for the purpose of comparison.

Insulation coating layer manufacture for electric wire

The manufacturing method of the insulating material for the wire coating layer using the composition according to Examples 1 to 7 (see Table 1) and Comparative Examples 1 to 4 (see Table 2) according to the following table is described as follows.

Prepare the composition according to Examples 1 to 7 and the composition according to Comparative Examples 1 to 4, respectively (step S1). The prepared composition is added to a 120 L kneader and kneaded for 15 minutes (preferably 15 to 20 minutes) (step S2). The kneaded composition is extruded under an extrusion temperature of 150 ° C. (preferably 130 to 180 ° C.) using a 75 mm single screw extruder (step S3). The extruded flame retardant is irradiated with 8Mrad (preferably 5-10Mrad) electron beam and crosslinked (step S4).

Exam and evaluation

On the other hand, in Table 1, after measuring the modulus at high temperature (105 ℃) and room temperature with respect to the resin composition according to Examples 1 to 7, respectively, the modulus ratio was calculated and expressed as a percentage, and the crystal ratio was expressed. . On the other hand, Table 1 shows the results of evaluating the passability of the high flame retardant grade VW-1 standard and the resistance to cut-through for the insulating material prepared using the resin composition according to Examples 1 to 7. Evaluation results regarding the composition according to Comparative Examples 1 to 4 with respect to the evaluation items same as those of the embodiments are shown in Table 2 below.

division Example One 2 3 4 5 6 7 Composition  EVA    90    80    70    60    50    40    30  EPDM (EPR)    15    25    30    40    50    60  Modified EVA    10     5     5    10    10    10    10 Mg (OH) ₂   110   100   200   150 Al (OH) ₃   200   100   200   150  Zinc borate     5   100    10    20    20    20    20  Fatty acid processing aid     One     One     One     One     One     One     One  Tartaric acid processing aid     5     5     5     5     5     5     5  Antioxidant     3     3     3     3     3     3     3  Crosslinking agent     2     2     2     2     2     2     2 Properties  Room temperature modulus (kgf / mm2)    20    19    18    17    16    15    14  High temperature modulus (kgf / mm2)    15    15    14    15    13    12    12  Modulus ratio   75.0%   78.9%   77.8%   88.2%   81.3%   80.0%   85.7%  Decision ratio   45.0%   42.0%   40.0%   38.0%   37.0%   37.0%   38.0%  VW-1   pass   pass   pass   pass   pass   pass   pass  Cut-through   pass   pass   pass   pass   pass   pass   pass

In Table 1, the EVA is ethylene vinyl acetate, the EPDM is ethylene propylene rubber (EPR), the modified EVA is ethylene vinyl acetate with maleic anhydride introduced, the magnesium hydroxide (Mg (OH) ₂ ) and aluminum Hydroxide (Al (OH) ₃ ) was used as a flame retardant, the zinc borate was used as a flame retardant aid, calcium stearate (Ca-Stearate) as the fatty acid processing aid, zinc stannate was used as the tartaric acid processing aid. . On the other hand, the antioxidant and the crosslinking agent used a conventional well-known material for implementing the function.

The same evaluation items as in the evaluation items relating to the physical properties of the aforementioned embodiments were performed in the same manner as in Comparative Examples 1 to 5, and the results are shown in Table 2 below.

division Comparative example One 2 3 4 Composition  EVA     50     70     30     20  EPDM (EPR)     70  Modified EVA     10  HDPE     50     30     70 Mg (OH) ₂     90     50    100 Al (OH) ₃     50     50    100  Zinc borate      5     50      0     20  Fatty acid processing aid      One      One      One      One  Tartaric acid processing aid      5      5      5      5  Antioxidant      3      3      3      3  Crosslinking agent      2      2      2      2 Properties  Room temperature modulus (kgf / mm2)     60     22     50     11  High Temperature Modulus (㎏f / ㎠)     12     10     14      9  Modulus ratio    20.0%    45.5%    28.0%    81.8%  Decision ratio    65.0%    55.0%    70.0%    35.0%  VW-1   fail   fail   fail    pass  Cut-through   fail   fail   fail   fail

In Table 2, the EVA is ethylene vinyl acetate, the EPDM is ethylene propylene rubber (EPR), the modified EVA is ethylene vinyl acetate with maleic anhydride introduced, the HDPE is a high density polyethylene, the magnesium hydroxide (Mg (OH) ₂ ) and aluminum hydroxide (Al (OH) ₃ ) were used as a flame retardant, the zinc borate was used as a flame retardant aid, and as the fatty acid-based processing aid, calcium stearate, tartaric acid-based Zinc tartarate was used as a processing aid. On the other hand, the antioxidant and the crosslinking agent used a conventional well-known material for implementing the function.

As can be seen through Tables 1 and 2, it can be seen that the embodiments according to the present invention exhibit excellent properties compared to the comparative examples. Specifically, in embodiments of the present invention, it can be seen that the cut-through property suitable for use as an electric wire is secured by increasing the modulus ratio at high temperature and modulus at room temperature. In addition, even if the modulus ratio is high, the cut-through characteristics cannot be satisfied unless the minimum modulus value is 10 kgf / mm2 or more at high temperature. It is obvious that the advantages of the technical improvement according to the present invention can be further highlighted.

On the other hand, when the melting point of the crystal is similar to the test temperature (about 105 ℃) when using the composition according to the present invention shows a sudden volume change near the melting point of the resin. In contrast, in the case of amorphous, a sudden volume change cannot be observed. Therefore, the present invention is to maintain the crystallinity less than 50%, and the smaller the crystal content, the smaller the component exhibits a sudden volume change, thereby improving the cut-through characteristics.

Optimal embodiments of the present invention described above have been disclosed. Although specific terms have been used herein, they are only used for the purpose of describing the present invention in detail to those skilled in the art and are not intended to limit the scope of the present invention as defined in the claims or the claims.

According to the present invention, since the halogen element is not included in the composition composition used, it can be said to be more environmentally friendly than conventional halogen-based products during combustion, and it is possible to secure the flame retardancy required by the high flame retardant grade VW-1. In addition, it is possible to meet the cut-through characteristics to improve the productability, and in the case of using as an insulating material, in particular, an insulating coating layer for electric wire, it is preferable because the physical properties such as the required tensile strength and elongation can be secured well.

Claims (11)

5 to 5 or more selected from ethylene copolymers consisting of ethylene vinyl acetate (EVA), ethylene ethyl acrylate (EEA), ethylene butyl acrylate (EBA) and ethylene methyl acrylate (EMA) 80 parts by weight; and 5 to 20 parts by weight of modified polyolefin resin; And 100 parts by weight of a polyolefin-based resin which is a base resin containing 0 to 80 parts by weight or less of ethylene propylene rubber. 110 to 300 parts by weight of the metal hydroxide which is an inorganic flame retardant; 5 to 100 parts by weight of zinc borate which is a flame retardant aid; 0.5 to 20 parts by weight of fatty acid processing aid; 0.5 to 20 parts by weight of tartaric acid processing aid; And 0.5 to 5 parts by weight of antioxidant; composition for producing a non-halogen flame retardant insulating material having a cut-through property, characterized in that it comprises a. The method of claim 1, The modified polyolefin resin is characterized in that the one or two or more selected from polyethylene (PE), high density polyethylene (HDPE), ethylene vinyl acetate (EVA) and linear low density polyethylene (LLDPE) is modified from a mixed resin A non-halogen flame retardant insulating material manufacturing composition having cut-through characteristics. The method of claim 1, The metal hydroxide which is the inorganic flame retardant is a non-halogen having cut-through characteristics, characterized in that any one selected from magnesium hydroxide (Mg (OH) ₂ ) and aluminum hydroxide (Al (OH) ₃ ) or a mixture of the two. Composition for producing a flame retardant insulating material. The composition for producing a non-halogen flame retardant insulating material according to any one of claims 1 to 3 has a cut-through characteristic, characterized in that it is used to prepare a coating layer for a non-halogen flame-retardant wire having a cut-through property. Non-halogen flame retardant insulation composition. The insulating material prepared by using the composition for producing a non-halogen flame retardant insulating material according to any one of claims 1 to 3 has a modulus of at least 10 kgf / mm2 at 105 ℃, the modulus at 105 ℃ at room temperature Non-halogen flame retardant insulation composition having a cut-through characteristic, characterized in that more than 75% of the modulus of the. A composition for producing a non-halogen flame retardant insulating material according to claim 5, wherein the composition for producing a non-halogen flame retardant insulating material is used to manufacture a coating layer for a non-halogen flame-retardant wire having cut-through properties. The method of manufacturing an insulating material using any one of the compositions selected from claim 1 to claim 3, wherein the step of crosslinking the resin in the composition for producing the insulating material is any one selected from water crosslinking method, chemical crosslinking method and irradiation crosslinking method. A non-halogen flame-retardant insulating material manufacturing method having a cut-through characteristic, characterized in that it proceeds by the method of. The non-halogen flame retardant insulating material manufacturing method according to claim 7 is used as a method for producing a non-halogen flame retardant wire coating layer having a cut-through property. delete delete delete