KR101193976B1 - Flame-retardant material with the boron composition, and it - Google Patents

Abstract

PURPOSE: A borate-based flame retardant composition is provided to good molding effect in state a melting point is reduced by mixing boron-based flame retardant powder and ethylene vinyl acetate to moderate mixing ratio and to obtain good mechanical properties. CONSTITUTION: A borate-based flame retardant composition is manufactured through a step of mixing 100.0 parts by weight of ethylene-vinyl acetate as a base resin in a kneader for 9 minutes in advance, a step of adding 10-200 parts by weight of powder type sodium polyborate, 0.3-9 parts by weight of azodicarbonamide-based foaming agent, 0.5-3 parts by weight of t-butyl peroxyneodecanoate crosslinking agent and 2-12 parts by weight of hindered phenol-based lactone based antioxidant, a step of mixing the additive mixture for 3 minutes, pulverizing the mixture through a resin pulverizer, and a step of putting the same into a twin screw extruder(diameter=30mm, l/d=29).

Description

Boron-based flame retardant composition and flame retardant material using the same

The present invention relates to a boron-based flame retardant composition and a flame retardant material using the same, and more particularly, a state in which melting point is suppressed by mixing boron-based flame retardant (particularly, sodium polyborate) powder with ethylene vinyl acetate (EVA) at a mixing ratio of a family register. It relates to a boron-based flame retardant composition and a flame retardant material using the same to obtain an easy molding effect in the.

In general, styrene-based plastics are mainly used as exterior materials for electrical and electronic products because of their excellent processability and mechanical strength.In countries such as the United States and Europe, flame retardant resins can be used to increase the safety of electronic products. It is legal to use only.

The plastic itself is not resistant to flame, and when the spark is ignited by an external ignition source, the resin itself acts as an energy to assist combustion, thereby continuously spreading the fire.

Flame-retardant properties of plastics with these properties include additive-based flame retardants, which add a flame retardant and auxiliary flame retardants, and polymerized flame retardants that produce resins using special monomers containing flame-retardant atoms during polymerization. Can be divided into speech.

Among them, the polymerization type flame retardant method has been studied in the experimental stage, but due to the high cost and difficulty of achieving flame retardancy, commercialization is slow. Therefore, most commercially available flame retardant resins have an additional flame retardant method in which a flame retardant containing halogen or phosphorus, which is an inert element during compounding, is mainly selected from halogen-containing organic compounds and antimony-containing organic compounds. It is prepared by adding to the resin. Halogen-containing organic compounds, mainly bromine or chlorine compounds, are highly flame retardant when added to styrene-based resins, but seriously deteriorate overall physical properties such as impact strength, UV stability, heat resistance and processability of the resin itself. Therefore, in producing a flame retardant resin, a technique of imparting excellent flame retardancy while minimizing a decrease in physical properties of the resin is very important.

In recent years, as the building materials and home appliances, which are the main uses of the flame retardant resins, have been gradually enlarged and diversified, a high flowability flame retardant resin having excellent moldability and workability has been required. In order to increase the fluidity of the resin, a flame retardant having excellent flowability should be used. In the styrene resin, a melt flame retardant having a low melting point is mainly used. However, molten flame retardants are not more flame retardant than filler flame retardants, so in order to exhibit flame retardancy that meets the US UL (Underwriters Laboratories) standard, it is inevitable that excessive addition is required, resulting in severe degradation of physical properties. Have.

The present invention has been made to solve the above-mentioned conventional problems, the main object of the present invention is to provide a boron-based flame retardant composition excellent in flame retardancy or quasi-incombustibility compared to the filling flame retardant despite the melt-type flame retardant.

Another object of the present invention, by mixing the ethylene vinyl acetate (EVA) and the boron-based flame retardant (particularly sodium polyborate) that serves to suppress the melting point, extrusion molding, injection molding, etc. that was not possible due to melting point imbalance It is to provide a boron-based flame retardant composition that can facilitate the resin molding operation of.

Still another object of the present invention is to provide a flame retardant material prepared by injection, injection molding or other molding method of the boron-based flame retardant composition.

According to a first aspect of the present invention for achieving the above object, 100 parts by weight of ethylene-vinyl acetate (EVA) as a base resin is first mixed in a kneader for 9 minutes, and then 10 to 200 weight of powdered sodium polyborate Part, 0.3 to 9 parts by weight of azodicarbonamide-based blowing agent, 0.5 to 3 parts by weight of t-butylperoxy neodecanoate crosslinking agent, hindered phenol or lactone antioxidant 2 After adding 12 parts by weight to further mix for 3 minutes, the mixture is pulverized with a resin grinder, and then fed to a biaxial resin extruder (diameter = 30 mm, l / d = 29) to provide a boron-based flame retardant composition.

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In addition, in 100 parts by weight of the ethylene vinyl acetate (EVA), vinyl acetate (VA) is characterized in that 10 to 45 parts by weight.

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In the present invention described above, the boron-based flame retardant powder is kneaded with ethylene vinyl acetate (EVA) at a mixing ratio of a family register, so that an easy molding effect can be obtained in a state in which melting point is suppressed, and good mechanical properties can be obtained.

Hereinafter, embodiments according to the present invention are disclosed.

In the disclosed embodiments, the same reference numerals refer to the same configuration, and additional descriptions that may overlap or limit the meaning of the invention may be omitted in describing the embodiments of the present invention.

Prior to the detailed description, the concept of the invention, in spite of the singular form of the present disclosure, in the light of the circumstances in which the singular / plural is not clearly distinguished in the use of Korean and in the ordinary terminology used in the art. It is used in the sense that it includes plural expressions unless otherwise contradictory or clearly different from each other. In addition, the words "include", "have", "include", "comprise", or the like described or described in this specification may indicate in advance the possibility of the presence or addition of one or more other features or components, or a combination thereof. It should be understood that it does not exclude.

In addition, in the present invention, 'composition' is a term that includes the meaning of the original mixture and the compound, in the present invention 'composition' of the 'binder composition' is a 'mixture', unless otherwise stated or contrary to the overall content of the invention It is used to mean '.

The present invention relates to a boron-based flame retardant composition and a flame retardant material using the same. However, it is assumed that the present invention may also be provided in semi-combustible compositions and semi-combustible materials. For reference, flame retardant (material) means that it does not burn itself when it is put in fire but does not burn itself when it is burned out (fire retardant class 3), non-combustible means property that does not burn even when put in fire (flame retardant class 1), Semi-non-combustible means having properties similar to non-combustible (flame retardant class 2).

The boron-based flame retardant composition according to the present invention is made by kneading 5 to 200 parts by weight of boric acid-based flame retardant powder to 100 parts by weight of the base resin.

The base resin, which is one component of the boron-based flame retardant composition according to the present invention, including ethylene vinyl acetate (ethylene), ethylene-ethyl acrylate copolymer (ethylene-ethyl acrylate copolymer), ethylene-butylacryl Ethylene-butyl acrylate copolymer (EBA), low density polyethylene (LDPE), high density polyethylene (HDPE), linear low density polyethylene (LLDPE), polypropylene copolymer ( polypropylene copolymer (PP), polyvinyl chloride (PVC), chlorinated polyethylene (CPE), chlorosulfonated polyethylene (CSM), polychloroprene (CR) and polyvinylidene Fluoride (poly vinylidene fluoride, PVDF) may preferably be used, these alone or It may be used interchangeably with the above.

In particular, in the present invention, it is recommended that ethylene vinyl acetate (EVA) is used.

Ethylene vinyl acetate has high flexibility as a building material because of its flexibility, adhesion, toughness (particularly impact resistance), heat sealability, cold resistance, optical properties (gloss, transparency, etc.), scratch resistance, and ethylene vinyl acetate (EVA). The melting point can be adjusted according to the content ratio of vinyl acetate (VA). For example, when the compounding ratio of vinyl acetate (VA) is 10 parts by weight based on 100 parts by weight of ethylene vinyl acetate, the melting point is about 94 ° C., and the melting point is lowered to 61 ° C. when the ratio of VA is 33 parts by weight. At this time, the compounding weight range of preferable vinyl acetate is 10-45 weight part, and a more preferable vinyl acetate compounding weight is 10 weight part. When the vinyl acetate is blended in the above range (10 parts by weight or less), the effect of lowering the melting point is insignificant, and when the vinyl acetate is blended in the above range (more than 45 parts by weight), slippage occurs between molecules, thereby lowering the breaking point tension.

As such, when the vinyl acetate in the ethylene vinyl acetate is contained and the melting point of the ethylene vinyl acetate is suppressed to 100 ° C. or less, local foaming of the sodium polyborate kneaded therewith can be prevented, thereby enabling good molding.

The boron-based flame retardant which is this component of the boron-based flame retardant composition according to the present invention may be used, for example, sodium polyborate. Sodium polyborate (sodium) is a flame retardant foamed upon contact with a flame, 35 parts by weight of boric acid (H ₃ BO ₃ ), 40 parts by weight of heavy rain sand (Na2B ₄ O ₇ ~ 10 H ₂ O) with respect to 100 parts by weight of water It can be obtained by adding a part, dissolving by heating to 70-90 degreeC, and cooling to room temperature. Since the sodium polyborate is in an aqueous solution state, it can be obtained in powder form by a known evaporation drying method such as spray drying (spray drying method) in which an aqueous solution is sprayed in hot air and dried instantly.

The sodium polyborate is kneaded in an amount of 5 to 200 parts by weight based on 100 parts by weight of the base resin. When kneaded at 5 parts by weight or less, the flame retardant performance is drastically reduced. While there is no significant improvement, the economy is poor due to the excessive input of materials.

The boron-based flame retardant composition according to the present invention may further include an antioxidant. It is preferable that the said antioxidant contains 2-12 weight part with respect to 100 weight part of said base resins. If the antioxidant is less than the above lower limit, it is difficult to exert sufficient effect by the addition. If the antioxidant is exceeded, the economy is inferior due to the excessive addition. Preferred antioxidants include hindered phenol- or lactone-based antioxidants, and phosphite and thioester-based antioxidants are added to further enhance the antioxidant effect. Can be used.

The boron-based flame retardant composition according to the present invention may further include a blowing agent for foaming. The blowing agent is an azo compound such as azodicarbonamide, a nitroso compound such as N, N'-dinitrosopentamethylenetetramine, p-toluenesulfonylhydrazide and p, p'-oxybis ( Sulfonylhydrazide compounds such as benzenesulfonylhydrazide), p-toluenesulfonyl semicarba, azobisisobutyronitrile and diazoaminoazobenzene, at least one having a decomposition temperature of 110 to 180 캜, and EVA It is preferable that 0.3-9 weight part is contained with respect to 100 weight part of copolymers. If the blowing agent content is less than 0.3 parts by weight, the hardness and specific gravity are very high, and if it exceeds 9 parts by weight, foam of a stable cell structure cannot be obtained due to excessive foaming, and the mechanical properties of the foam are sharply deteriorated.

The boron-based flame retardant composition according to the present invention may further include a crosslinking agent for chemical bonding of the composition. The crosslinking agent is t-butylperoxy neodecanoate, t-butylperoxy pivalate, t-butylperoxy-2-ethylhexanoate, 1,1-di (t-butylperoxy) cyclohexane, t It is preferable to select from -butyl cumyl peroxide and t-butyl peroxy benzoate, and 0.5-3 weight part is included with respect to 100 weight part of said base resins. If the content of the crosslinking agent is less than 0.5 parts by weight, the crosslinking effect is insignificant. If the content of the crosslinking agent is more than 3 parts by weight, the cell structure becomes excessively dense due to excessive crosslinking during crosslinking and foaming, resulting in poor workability and workability during crosslinking and foaming.

Alternatively, vinyl tris (2-methoxyethoxy) silane may be applied as the crosslinking agent.

In addition, the boron-based flame retardant composition according to the present invention may further include various additives within a range that does not inhibit the effects of the present invention. Examples thereof include UV inhibitors, heat stabilizers, lubricants, enblocking agents, antistatic agents, waxes, coupling agents, pigments, processing aids, carbon blacks and the like.

Referring to the process for producing a flame retardant material using a boron-based flame retardant composition according to the present invention.

The base resin, sodium polyborate, antioxidant, blowing agent and crosslinking agent are mixed at a temperature above the melting point of the base resin using a kneader or banbury mixer or the like. The mixture is fed directly from the kneader to the extruder hopper and fed directly into the melt, or pulverized to a suitable size with a resin mill and then fed into the extruder in a solid state. The injected mixture is extruded using a single-screw or twin-screw extruder for resin at a temperature of 70-150 ° C. to prepare pellet-like samples. At this time, the extrusion temperature should be selected within the temperature range that is above the melting point of the base resin and below the decomposition temperature of the blowing agent. If the extrusion temperature is 70 ° C. or less, the resin is not sufficiently melted and the resin melt pressure is excessively increased, making it difficult to extrude. If the temperature is 150 ° C. or higher, the resin is easily melted, but excessive crosslinking and foaming occur, which causes extrusion. it's difficult. After sufficiently drying the prepared pellet sample using a dryer, an appropriate amount of pellets were put into a mold and extruded for 2 to 70 minutes at a high temperature and pressure of 120 to 180 ° C. and 3 to 520 kgf / cm ² . By opening the mold instantaneously and demolding and foaming at the same time, a flame retardant material is produced.

Such flame retardant materials may be utilized as construction pads, wires, tent sheets, films, and the like.

Hereinafter, although an Example and a comparative example demonstrate this invention in detail, this invention is not limited by this.

Example  1-4

In Examples 1 to 4, as shown in Table 1, ethylene-vinyl acetate (EVA) was first mixed in a kneader for about 9 minutes as a base resin, followed by powdered sodium polyborate 80 g and its corresponding A mixture of 2 g of azodicarbonamide blowing agent and 2 g of t-butylperoxy neodecanoate crosslinking agent was further added, followed by further mixing for 3 minutes, and the total mixing time was 12 minutes. The mixture was pulverized with a resin pulverizer, and then put into a twin screw extruder (diameter = 30 mm, l / d = 29) and extruded to obtain a flame retardant composition according to the present invention in pellet form.

The appropriate amount of the obtained flame retardant composition pellets was put in a mold, compression molded at 130 ° C. for 30 minutes, and then foamed to prepare a pad-type flame retardant material using the flame retardant compositions of Examples 1 to 4, and its physical properties were measured.

Comparative example

As a comparative example for the flame retardant materials prepared using the flame retardant compositions of Examples 1 to 4, ethylene vinyl acetate (EVA) was used as the base resin as indicated in [Table 2], and thus sodium polyborate Instead, halogen-based flame retardants were used, and the physical properties thereof were measured in the same manner as in Examples 1 to 4.

The physical property measurement results of the flame retardant materials prepared using the flame retardant compositions of Examples 1 to 4 are shown in [Table 1].

In addition, the measurement results of the physical properties of the flame retardant materials manufactured using the flame retardant compositions of Comparative Examples 1 to 4 are shown in [Table 2].

Property measurement method

The physical properties of the pad-type flame retardant materials prepared by Comparative Examples and Examples 1 to 4 were measured by the following method.

Ⓛ Specific gravity

The specific gravity of the flame-retardant material was measured three times using the automatic specific gravity measuring apparatus after removing the surface of the pad type flame-retardant material, and the average value was taken.

② tensile strength and elongation

After removing the surface of the flame-retardant material and the thickness of 5mm, the specimen was cut with a specimen-shaped cutter, and the tensile strength and elongation were measured by ASTM D-412 method. At this time, the tensile speed was 500mm / min, and the average value was taken five times per test piece.

③ permanent compression reduction rate

After making a cylindrical specimen with a thickness of 15 mm and a diameter of 35 mm, a test piece is placed between two parallel metal plates, a spacer equal to 50% of the thickness of the test piece is inserted, and then compressed into an oven. After heat treatment at 60 ° C. for 7 hours, the test piece was taken out from the compression apparatus, cooled at room temperature for 40 minutes, and then the thickness thereof was measured.

④ flame retardant

The evaluation of flame retardancy was based on the vertical combustion test of the UL Subject 94 (Underwriters Laboratories Incorporation) "Combustibility Test of Plastic Material for Mechanical Components" in the vertical phase (VO). The test fraction used was 1/40 inch thick.

Property measurement result

As a result of comparing Examples 1 to 4 and Comparative Example, specific gravity, tensile strength and elongation of Examples 1 to 4 were generally superior to Comparative Examples.

On the other hand, although not mentioned in the above examples, when the content of vinyl acetate (VA) to ethylene vinyl acetate (EVA) in the range of 10 to 45 parts by weight can lower the melting point of ethylten vinyl acetate, so that Local abnormal foaming can be prevented, and a good molding can be performed.

Example 1 Example 2 Example 3 Example 4 Ethylene Vinyl Acetate Content (g) 100 100 100 100 Sodium polyborate (g) 10 20 100 200 Blowing agent (g) 0.3 One 3 9 Crosslinking agent (g) 0.5 1.2 2.5 3 Specific gravity (g / cm ³ )
0.23 0.17 0.19 0.16 Tensile Strength (kg / cm ² )
25 20 20 16 Elongation (%) 250 260 270 250 Heat deformation temperature (℃) 98 97 98 95

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Ethylene Vinyl Acetate Content (g) 100 100 100 100 Halogen flame retardant (g) 10 20 100 200 Blowing agent (g) 0.3 One 3 9 Crosslinking agent (g) 0.5 1.2 2.5 3 Specific gravity (g / cm ³ )
0.14 0.09 0.1 0.13 Tensile Strength (kg / cm ² )
19 14 12 17 Elongation (%) 240 250 252 220 Heat deformation temperature (℃) 68 70 71 70

Claims (11)

100 parts by weight of ethylene-vinyl acetate (EVA) as a base resin was first mixed in a kneader for 9 minutes, and then 10 to 200 parts by weight of powdered sodium polyborate and 0.3 to 9 weight of azodicarbonamide-based blowing agent Parts, 0.5 to 3 parts by weight of t-butylperoxy neodecanoate crosslinking agent, 2 to 12 parts by weight of hindered phenol or lactone-based antioxidant are added, and further mixed for 3 minutes, and the mixture is mixed. After grinding with a resin mill, a boron-based flame retardant composition prepared by feeding into a twin screw extruder (diameter = 30mm, l / d = 29).
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Boron flame retardant composition, characterized in that the vinyl acetate (VA) is 10 to 45 parts by weight in 100 parts by weight of the ethylene vinyl acetate (EVA). delete delete