KR100886845B1 - Incombustibility improved polystyrene foam bead and the method for producing polystyrene foam bead thereof - Google Patents

Abstract

A method for manufacturing flame retardant polystyrene foam bead is provided to prepare styrofoam with high water resistance and high fire retardant characteristic by using an inexpensive flame retardant. A method for manufacturing flame retardant polystyrene foam bead comprises (S1) a step for mixing one or at least two organic solvents selected from hexane, benzene, toluene, xylene, diethyl ether, chloroform, ethyl acetate, dioxane, tetrahydrofuran, dichloromethane, acetone, acetonytryl, dimethylformamide, dimethyl sulfuroxide, acetic acid, N-butanol, isopropanol, N-propanol, ethanol, methanol, formic acid, cyclohexanone, polypropylene acetate, styrene, and styrene butadiene, and spraying the solvent in beads; (S2) a step for spraying a flame retardant mixed with one or more selected from an alkaline earth metal compound, magnesium oxides, zinc, and zinc oxides, in the beads coated with the organic solvent, to adhere the flame retardant; and (S3) a step for spraying a sodium silicate-based binder in the bead passed though the (S2) step to coat the beads.

Description

Incombustibility improved polystyrene foam bead and the method for producing polystyrene foam bead featuring a coating layer

The present invention generally relates to a polystyrene bead that is a raw material used to prepare styrofoam. In general, styrofoam has a disadvantage of being susceptible to heat because of its good thermal insulation property but its lack of flame retardancy.

In the fire, polystyrene, a component of styrofoam, was burned, releasing soot, odor, and strong harmful substances, causing a great physiological and environmental problem.

In addition, styrofoam has a big problem that it is difficult to extinguish in case of fire because it is used as insulation material inside the building.

Therefore, in order to give a great flame retardancy to such styrofoam, many technicians have been proposed a number of techniques for producing flame retardant polystyrene beads.

As a method for producing a flame retardant styrofoam as described above, techniques for flame retarding unfoamed polystyrene particles (normally polystyrene beads, hereinafter simply beads) have been disclosed.

In the prior art, a flame retardant is coated on a surface of a bead and a flame retardant such as a halide, a phosphate, or a brominated organic compound is foamed to produce a flame retardant styrofoam, or a mixture of porous mineral particles such as zeolite, bentonite, pearlite, and illite is compressed and molded. There is a technique to do.

In addition, the beads are crushed to apply a coating agent consisting of sodium silicate and calcium carbonate to foam, or a flame retardant composition containing sodium silicate and calcium carbonate, aluminum hydroxide, talc, and the like is applied, followed by drying by microwave heating. It was also foamed.

However, the above-mentioned conventional technologies have disadvantages in that the manufacturing process is difficult and the manufacturing cost is high, and the coating material used as the flame retardant is not only expensive but also inferior in flame retardancy as well as in the formability of foam molding of styrofoam. In addition, even the molded product could not guarantee the uniformity of quality.

In addition, there was a problem that a method of preparing general beads into flame retardant polystyrene beads, that is, a method of coating a silicic acid-based flame retardant on the beads was not specifically presented.

Therefore, in reality, the silicate-based flame retardant coated beads were hardly produced, and the beads coated with the silicic acid-based flame retardant were difficult to be molded into styrofoam, and even if foamed and molded, the styrofoam was cracked or cracked.

Therefore, in order to manufacture foams into stable styrofoam and to manufacture realistic and practical flame retardant styrofoam, it is necessary to prepare flame retardant polystyrene beads by adhering a flame retardant to the raw material beads and coating a silicic acid-based flame retardant uniformly and stably. It has emerged.

In order to solve the above problems,

Ordinary beads are prepared, and an organic solvent or a mixed solution obtained by mixing and dissolving ordinary beads in an organic solvent is prepared.

The organic solvent or the mixed solution is applied to the beads by spraying with an injector that produces droplets that are significantly smaller than the beads (particles).

Flame retardant powder is sprayed onto the beads coated with the organic solvent or mixed solution to evenly adhere the flame retardant powder.

A flame retardant polystyrene bead is prepared by performing a process of evenly spraying a sodium silicate-based binder on the beads to which the flame retardant powder is adhered several times and coating and drying the same.

When the styrofoam is produced through the foaming process and the molding process, the flame-retardant polycyrene beads prepared as described above are produced significantly, and the flame retardant styrofoam is a finished product without any cracks having good moldability.

According to the present invention, a "flame retardant polystyrene bead" which is a raw material of styrofoam having high water resistance and remarkably high flame retardancy was prepared.

In particular, it has an effect of completely preventing the cracks of the molded styrofoam, it is possible to manufacture a very inexpensive flame-retardant styrofoam using economical low-cost flame retardant material instead of the conventional expensive flame retardant material.

In addition, the polystyrene beads according to the present invention can be produced through the foaming and molding process, which is a common technique, to produce styrofoam that is lightweight, strong insulated, and heat resistant, and thus can be used for various purposes such as building insulation insulation, impact buffer, etc. Supply is also expected to significantly increase demand.

In addition, since the present invention relates to a method for producing flame retardant polystyrene beads using general beads before foaming, and a flame retardant polystyrene bead and a flame-retardant styrofoam which is a foam thereof, it is easy to supply the flame retardant polystyrene beads to a factory for producing styrofoam. Therefore, it is possible to manufacture a flame retardant styrofoam, significantly reducing the logistics cost, there is also an effect that can be easily transported where the flame retardant styrofoam is needed.

The present invention relates to a "method for producing flame retardant polystyrene beads by preparing polystyrene beads (hereinafter referred to simply as" beads "), which are raw materials used to prepare styrofoam, and to" flame retardant polystyrene beads "prepared by the method. .

It also relates to a "method for producing a flame retardant styrofoam" using this flame retardant polystyrene bead and a molded article "flame retardant styrofoam".

First, "bead" means round particles in which hydrocarbon gas, such as pentane or butane, is injected into polystyrene resin, and generally means that flame retardant treatments from Cheil Industries, LG, Dongbu, and BASP are not performed.

A feature of the present invention is to apply a predetermined amount of a solution (hereinafter mixed solution) in which an organic solvent or an organic solvent and beads are mixed and dissolved in the beads that are not flame retardant, and then spray a predetermined amount of the flame retardant powder to uniformly adhere to the beads. The powder-adhered beads are sprayed evenly over several times to coat and dry a predetermined amount of sodium silicate-based binder (preferably a water-resistant sodium silicate binder) to make flame-retardant polystyrene beads.

When the styrofoam is produced through the foaming process and the molding process, the flame-retardant polycyrene beads prepared as described above are significantly increased in flame retardancy, and thus the flame-retardant styrofoam is manufactured as a finished product without any cracks having good moldability.

The present invention.

First, 0.1-1.2 parts by weight of an organic solvent is added to 100 parts by weight of beads, and sprayed on the beads with droplets (fine mist form) significantly smaller than those of beads with a high-pressure injector at room temperature to coat the surface of the beads.

Although it can be used as a conventional injector, it is very useful to use a high-pressure injector to make fine droplets. These small droplets must be evenly sprayed onto the beads to dissolve the bead granules so that they can easily adhere to the flame retardant powder.

Therefore, in the case of the use of the range smaller than the organic solvent usage, the state of dissolution of the bead grain surface is reduced, so that the flame retardant powder does not stick evenly to the bead grain surface. Melting and cracking of beads cause the foaming gas in the beads to leak, not only to be molded into styrofoam, but also to cause beads to fuse together.

The organic solvent can be any conventional organic solvent, and there are hexanes, benzenes, toluenes, xylenes, diethyl ethers, chloroforms, ethyl acetates, and the like, which are nonpolar solvents, depending on the type of solvent. Dioxanes, tetrahydrofuran (THF), dichloromethane (DCM), acetone, acetonitrile, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO), which are magnetic solvents (Polar Aprotic Solvents) Polar Protic Solvents include acetic acid, N-butanol, isopropanol (IPA), N-propanol, etarol, methanol and formic acid. Drew, etc., all of which can be used as a solvent for melting polystyrene beads.

Moreover, cyclohexanone, propylene acetate, styrene, styrene butadiene, etc. can be used as another organic solvent.

However, the organic solvent is not limited to the above-mentioned organic solvents, and in general, any solvent can dissolve the bead surface.

In the case where the organic solvent is sprayed onto the bead, the organic solvent may be used alone, but the organic solvent may be mixed (hereinafter referred to as a mixed organic solvent).

However, the organic solvent is preferably used alone, it is recommended to use a mixture of the same properties. In addition, using an organic solvent free from chlorine does not cause environmental problems. Even more preferably, it is preferable to use a nonpolar solvent, and in particular, to use xylenes and toluenes. This is because xylenes and toluenes are non-polar and have a high boiling point and are excellent solvents. In addition, styrene is also called vinylbenzene, which corresponds to a very good organic solvent, and thus it is also preferable to use it.

As one of the most characteristic features of the present invention, a mixed solution (hereinafter referred to as a mixed solution) in which an organic solvent is mixed with ordinary beads to dissolve the beads is sprayed onto the beads and applied.

In this case, the mixing ratio of organic solvent and beads is 1: 0.05-0.3 weight ratio.

As the organic solvent, the above-mentioned organic solvents are used, and beads may be used alone or in combination of several organic solvents.

In addition, the organic solvent is not limited to the above-mentioned organic solvents, and in general, any solvent can dissolve the bead surface.

However, it is preferable to use alone, and it is recommended to use a mixture of solvents having the same properties, if possible. It is also preferable to use an organic solvent free of chlorine, and more preferably to use a nonpolar solvent.

In particular, xylenes and toluenes are non-polar and have a high boiling point, which is a preferable organic solvent because they are excellent solvents. In addition, styrene is also called vinyl benzene, which corresponds to a very good organic solvent. When styrene is melted as a monomer of polystyrene and sprayed onto bead granules, it is very effective for adhering flame retardant powder to the bead granule surface.

In the case of mixing the beads lower than the mixing ratio of the organic solvent and the beads, when the mixed solution is sprayed on the beads, the surface of the bead grains is excessively dissolved, so that the polystyrene bead grains are broken and the hydrocarbon gas inside the grains is leaked and the beads are fused together. The phenomenon occurs, and when the beads are excessively dissolved in excess of the mixing ratio, the surface of the bead grains does not dissolve properly when sprayed on the beads, so that the flame retardant powder does not stick well.

Then, the beads are placed in a rotary mixing stirrer and the above-described organic solvent or mixed solution is sprayed on the beads with a high pressure sprayer to apply polystyrene beads. This process is sufficiently possible at room temperature.

The organic solvent is used in an amount of 0.1-1.2 parts by weight based on 100 parts by weight of beads as mentioned above.

In addition, the mixed solution usage amount is 0.25-1.25 weight part with 100 weight part of beads.

When spraying the organic solvent or the mixed solution on the surface of the bead granules, the method of spraying on the surface of the bead granules may be selected, and preferably, a means for spraying the mixed solution in the same concentration on the entire polystyrene bead granules may be employed.

In addition, as mentioned above, when injecting an organic solvent or a mixed solution, it should be sprayed to have a droplet that is significantly smaller than the grains of the beads. Although it may be used as a conventional injector, it is preferable to use a high pressure sprayer to spray like fine mist to uniformly apply the polystyrene beads that are stirred in the rotary mixing stirrer.

Therefore, when the organic solvent or the mixed solution is sufficiently applied to the surface of the bead grains as described above, the surface of the bead grains is slightly melted, and the flame retardant powder to be described below can be sufficiently adhered.

Thus, the bead coated with the organic solvent or the mixed solution sufficiently uniformly proceeds to the process of adhering the flame retardant powder which is the next step.

The beads coated with the organic solvent or the mixed solution are in a state where the surface of the bead granules is melted to a very fine thickness and thus forms stickiness. Therefore, the flame retardant powder is sprayed onto the surface of the bead grains which are stirred and mixed in a rotary mixing stirrer. Evenly enough to stick. This process is also possible to proceed at room temperature and the beads are agitated in a rotary mixing stirrer while the flame retardant powder is sprayed, and because the flame retardant powder does not adhere to each other, they adhere to a uniform concentration on the surface of the beads.

In addition, the particle size of the flame retardant powder is in the form of fine powder having an average of about 1-100 μm, that is, it has a powder form having a significantly smaller diameter than the beads, so that it can stick very uniformly to all the viscous beads formed thereon. will be.

The flame retardant powder may be alkaline earth metal oxide, zinc or zinc oxide, and may be used alone or in combination. Preferably, it is preferable to use magnesium oxide powder, zinc powder, zinc oxide powder, which are inexpensive, highly flame retardant, and have low molecular weight.

The amount of flame retardant powder used is 2.5-7.5 parts by weight based on 100 parts by weight of beads. Preferably, 4-6 parts by weight is appropriate in terms of economics and flame retardancy.

In this way, the flame retardant powder is evenly adhered to the surface of each grain of the beads so that the flame retardancy of the polystyrene beads is significantly increased.

These flame-retardant powder-adhered beads have a very smooth surface and have sufficient fluidity so that the polystyrene bead grains do not adhere to each other. Due to this property, the process of adhering the next process, the sodium silicate-based binder, may be facilitated.

Next, the flame-retardant powder-coated beads are sprayed onto a soda silicate-based binder to coat the entire surface of the polystyrene bead-coated grains.

As a sodium silicate-based binder, a conventional sodium silicate binder is used, and preferably, a water-resistant water-resistant sodium silicate binder is preferably used (collectively referred to as a sodium silicate-based binder collectively called a sodium silicate binder and a water-resistant sodium silicate binder).

The water-resistant sodium silicate binder means a water-soluble sodium silicate binder prepared by a conventional method, and thus contains water dispersible alkali silicate, water dispersible silica, and water dispersible silica coated with an organic functional silane compound as a coating agent. Ordinary water resistance, which contains a hydrolysis reaction product hydrolyzed with water dispersible alumina to an organic functional silane compound as a coating agent, or a water-resistant sodium silicate binder containing boric acid as a main component in a ceramic binder. It means a sodium silicate binder.

However, preferably, the water resistant sodium silicate binder means sodium silicate containing a water resistance accelerator. That is, a water resistance accelerator composed of 50-130 parts by weight of calcium deoxygenate and dissolved in 100 parts by weight of a 20-45% aqueous solution of potassium deoxyderate, and 1-200 parts of water resistance accelerator added to 100 parts by weight of sodium silicate. it means.

The soda silicate-based binder is used in an amount of 1.5-5 parts by weight of a sodium silicate-based binder in 100 parts by weight of polystyrene beads.

Then, at room temperature, the surface of the whole polystyrene bead grains to which the flame retardant component is adhered is completely coated by using a high-pressure injector so that the droplets are very fine at room temperature. Therefore, by spraying a soda silicate-based binder with a high-pressure injector to the beads adhering to the flame-retardant component is stirred in the rotary mixing stirrer to sufficiently coat the entire surface of the beads grains adhering to the flame-retardant component.

Thereafter, the beads coated with a flame retardant component coated with a sodium silicate-based binder are sufficiently dried at room temperature. Drying at room temperature typically takes about 10-25 minutes. In some cases, it is possible to induce rapid drying using a blower.

Then, the dried sufficiently coated silicate-based binder is sprayed by coating 1.5-5 parts by weight of the sodium silicate-based binder based on 100 parts by weight of the beads and dried. This process is possible at room temperature in the same manner as mentioned above, and in some cases can be dried with a blower.

Repeat this process three to four more times.

Therefore, the process of coating the sodium silicate-based binder is a total of one to six times.

The coating process of the sodium silicate-based binder is determined according to the physical properties of various types of sodium silicate binders, and can be adjusted according to the flame retardancy of the desired polystyrene beads. In general, three to six times is generally repeated, preferably five times.

The reason is that if the number of coatings of the sodium silicate-based binder is too small, proper flame retardancy cannot be secured. If the number of soda silicate-based binders is exceeded, cracks of the styrofoam may occur in the process of foam molding the polystyrene beads.

After the coating process of such a sodium silicate-based binder, the molding fusion is completed by using a foaming process and a high temperature steam, which is a normal styrofoam forming process, to complete a flame-retardant styrofoam molded body. In addition, the moldability is very excellent and the molded styrofoam molded body does not generate cracks at all. In addition, the molded flame retardant styrofoam has a fire resistance far higher than KSF 2271 grade 2 (semi-combustible material).

Embodiments of the present invention are as follows. However, the present invention is not limited to these examples and includes all implementations included in the detailed description of the present invention.

<Example 1>

20 kg of normal beads (Cheil Industries, Shinwoo) are prepared.

Again, 200 g of polystyrene beads are mixed with 1 kg of toluene to form a completely dissolved solution.

130 g of this mixed solution is taken and 20 kg of polystyrene beads are sprayed with a high pressure jet while stirring in a rotary mixing stirrer (product name Aiki), and all the beads are sufficiently coated at a uniform concentration.

Then, the grain surface of the bead to which this mixed solution is applied will have a slight melting effect.

Then, the bead coated with the mixed solution is sprayed with 1 kg of magnesium oxide powder (average particle size of about 20-50 μm), which is a flame retardant powder, and uniformly adheres the magnesium oxide powder to the surface of the bead grains which are stirred and mixed in a rotary mixing stirrer. Let's do it. In this process, magnesium oxide adheres uniformly and strongly to all the bead grains.

The magnesium oxide powder-adhered beads were sprayed with a rotary mixed stirrer while spraying 600 g of sodium silicate-based binder (one kind of monochemical sodium silicate) to coat all of the bead grain surfaces coated with magnesium oxide powder.

After that, dry sufficiently at room temperature for 15-20 minutes. At this time, it is also possible to dry naturally at room temperature, but may be dried using a blower to promote drying.

This sodium silicate coating and drying process is repeated four more times.

Through this process, flame retardant polystyrene beads were prepared.

Then, using the flame retardant polystyrene beads, the flame retardancy is rapidly improved through the foaming process, which is a conventional styrofoam forming process, and the molding and fusion process using high temperature steam, and a flame retardant styrofoam is formed into a very stable molded body.

This flame retardant styrofoam exceeds the KSF 2271 grade 2 standard.

<Example 2>

As in Example 1, a water-resistant sodium silicate binder was used as the sodium silicate-based binder.

At this time, 85 parts by weight of calcium carbonate was added and dissolved in 100 parts by weight of 33% aqueous potassium carbonate solution (hereinafter, referred to as a water resistance accelerator), and then 5 parts by weight of this water resistance accelerator was added to 100 parts by weight of sodium silicate. Means made by.

The water-resistant sodium silicate binder is coated with 3 parts by weight of 100 parts by weight of beads and dried. Again, this water-resistant sodium silicate binder coating drying process is repeated four times.

Through this process, flame retardant polystyrene beads were prepared.

Then, using the flame retardant polystyrene beads, the flame retardancy is rapidly improved and the flame retardant styrofoam is formed into a very stable molded body through the foaming process, the forming process using the high temperature steam, and the fusion process, which are common styrofoam forming processes.

This flame retardant styrofoam has become a high quality flame retardant styrofoam that exceeds the KSF 2271 grade 2 standard.

Example 3

In the same manner as in Example 1, in this case, the organic solvent is used styrene, and the flame retardant powder is zinc powder (average particle size about 10-30㎛).

The sodium silicate-based binder uses a water-resistant sodium silicate binder,

The water-resistant sodium silicate binder is prepared by dissolving 90 parts by weight of calcium carbonate in 100 parts by weight of 33% aqueous potassium carbonate solution (hereinafter referred to as a water resistance accelerator) and adding 8 parts by weight of this water resistance accelerator to 100 parts by weight of sodium silicate. use.

The water-resistant sodium silicate binder is used in an amount of 3.5 parts by weight based on 100 parts by weight of the beads. In addition, the coating process with the water-resistant sodium silicate binder was performed five times.

Through this process, flame retardant polystyrene beads were prepared.

After that, the flame retardant styrofoam is formed into a highly stable and flame-retardant molded article by using a flame-retardant polystyrene bead through a foaming process, which is a conventional styrofoam forming process, and a process of forming and fusion with high temperature steam.

This flame retardant styrofoam exceeds the KSF 2271 grade 2 standard.

Example 4

In the same manner as in Example 1, in which case an organic solvent was used without using a mixed solvent and toluene was used. 100 g, 150 g and 200 g of toluene are taken and sprayed on the beads.

The flame retardant powder is zinc oxide powder (average particle size of about 20-30㎛).

In addition, the coating process with the sodium silicate binder is performed about five times.

Through this process, flame retardant polystyrene beads were prepared.

After that, flame-retardant styrofoam is manufactured by using a flame-retardant polystyrene bead through a foaming process, which is a conventional styrofoam forming process, and high-temperature steam, through a molding and fusion process. Flame-retardant styrofoam was molded according to the amount of toluene, but slightly non-uniform than Examples 1, 2 and 3.

Example 5

In the same manner as in Example 1, in this case, the organic solvent is prepared by mixing acetic acid and N-butanol in a weight ratio of 1: 1 to 1 kg. Thereafter, 200 g of polystyrene beads are dissolved in this organic solvent mixture to form a mixed solution.

The flame-retardant powder is mixed with magnesium oxide and zinc oxide in a weight ratio of 2: 1 to prepare 1.2 kg, and then sprayed onto the surface of the bead grains to which the mixed solution is applied to undergo adhesion.

In addition, the coating process with the water-resistant sodium silicate binder is carried out six times.

Through this process, flame retardant polystyrene beads were prepared.

Then, the flame retardant styrofoam is formed into a highly stable and flame-retardant molded article by using the flame-retardant polystyrene beads through the foaming process which is a conventional styrofoam forming process and the molding and fusion process using high temperature steam.

The present invention is a flame retardant polystyrene bead and a method of manufacturing the flame retardant polystyrene bead that is a raw material for producing styrofoam used as a thermal insulation material of various construction materials and a buffer product of electronic products significantly increased flame retardancy, The invention relates to a method for producing a flame retardant styrofoam and a flame retardant styrofoam.

Therefore, the use of styrofoam is very infinite, but there is a problem of fire resistance that the weakness of heat, which is the biggest problem of styrofoam in the present situation, when manufacturing the flame retardant styrofoam according to the present invention will be spotlighted as a buffer product of the construction industry and various products Expect.

In particular, the technique of coating a flame-retardant material on the beads as a conventional technology is not only economical due to the high cost of the coating material, but also lacks the moldability, while the present invention is not only significantly lower manufacturing cost but also rapidly increase the fire resistance, light and stable flame retardant styrofoam It is expected that the demand will increase rapidly.

In addition, it is expected to strengthen the competitiveness of domestic companies in the trade reality, where regulations on flame retardancy are intensifying.

Claims (18)

Hexanes, benzenes, toluenes, xylenes, diethyl ethers, chloroforms, ethyl acetates, dioxanes, tetrahydrofuran (THF) s, dichloromethane (DCM) s, acetones, acetonitriles , Dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetic acid, N-butanol, isopropanol (IPA), N-propanol, etarol, methanol, Injecting organic solvents such as mixed acid, cyclohexanone, propylene acetate, styrene, styrene butadiene alone or in a mixture of two or more (first step), Spraying a flame retardant material alone or mixed with alkaline earth metal oxide, magnesium oxide, zinc, zinc oxide to the organic solvent-coated beads (second step), Characterized in that the step of coating the coating by spraying a soda silicate-based binder to the beads after the second step, How to prepare flame retardant polystyrene beads The method of claim 1, The organic solvent is one of toluene, styrene and xylene or mixed and the amount used to spray the beads is 0.1-1.2 parts by weight to 100 parts by weight of the beads, The flame retardant is an alkali earth metal oxide or zinc or zinc oxide or a mixture thereof and the amount of the flame retardant is 2.5 to 7.5 parts by weight based on 100 parts by weight of the beads, The amount of the soda silicate-based binder used is 1.5-5 parts by weight in 100 parts by weight, and the number of coatings is 1 to 6 times in one coating. How to prepare flame retardant polystyrene beads Flame retardant polystyrene beads made according to claim 1. Claim 4 was abandoned when the registration fee was paid. A method for producing a flame retardant styrofoam through the foaming, molding, fusion process of the flame retardant polystyrene beads prepared according to claim 3. Claim 5 was abandoned upon payment of a set-up fee. Flame retardant styrofoam prepared according to claim 4 The method according to claim 1 or 2, The sodium silicate-based binder is a water-resistant sodium silicate binder in which 1-200 parts by weight of 100 parts by weight of sodium silicate is added to 100 parts by weight of 20-45% aqueous potassium silicate solution in which 50-130 parts by weight of calcium nitrate is dissolved. Flame retardant polystyrene beads manufacturing method characterized in that Flame retardant polystyrene beads prepared according to claim 6 Claim 8 was abandoned when the registration fee was paid. A method of manufacturing a flame retardant styrofoam through the foaming, molding, and fusion process of the flame retardant polystyrene beads prepared according to claim 7. Claim 9 was abandoned upon payment of a set-up fee. Flame retardant styrofoam prepared according to claim 8 Hexanes, benzenes, toluenes, xylenes, diethyl ethers, chloroforms, ethyl acetates, dioxanes, tetrahydrofuran (THF) s, dichloromethane (DCM) s, acetones, acetonitriles , Dimethylformamide (DMF), dimethyl sulfoxide (DMSO), acetic acid, N-butanol, isopropanol (IPA), N-propanol, etarol, methanol, The beads are mixed in an organic solvent such as mixed acid, cyclohexanone, propylene acetate, styrene, styrene butadiene, or a solution obtained by mixing two or more of the above organic solvents in a weight ratio of 1: 0.05-0.3 (organic solvent: beads). To prepare a dissolved solution (hereinafter referred to as a mixed solution) (first step) Spraying the mixed solution onto the beads (second step), Spraying a flame retardant material mixed with alkali metal oxide, magnesium oxide, zinc, zinc oxide alone or a mixture of these materials to the beads coated with the mixed solution (third step), Characterized in that the injection through the step of spraying a soda silicate-based binder to the bead after the third step, How to prepare flame retardant polystyrene beads The method of claim 10, In the preparation of the mixed solution, the organic solvent is one of toluene, styrene, and xylene or mixed and used.  When the mixed solution is injected into the beads, the amount used is 0.25-1.25 parts by weight to 100 parts by weight of the beads, The flame retardant is an alkali earth metal oxide or zinc or zinc oxide or a mixture thereof and the amount of the flame retardant is 2.5 to 7.5 parts by weight based on 100 parts by weight of the beads, The amount of the soda silicate-based binder used is 1.5-5 parts by weight in 100 parts by weight, and the number of coatings is 1 to 6 times in one coating. How to prepare flame retardant polystyrene beads Flame retardant polystyrene beads made according to claim 10. Claim 13 was abandoned upon payment of a registration fee. Fire retardant styrofoam manufacturing method through the foaming, molding, fusion process on the flame retardant polystyrene beads prepared according to claim 12 Claim 14 was abandoned when the registration fee was paid. Flame retardant styrofoam prepared according to claim 13 The method according to any one of claims 10 to 11, The sodium silicate-based binder is a water-resistant sodium silicate binder in which 1-200 parts by weight of 100 parts by weight of sodium silicate is added to 100 parts by weight of 20-45% aqueous potassium silicate solution in which 50-130 parts by weight of calcium nitrate is dissolved. Flame retardant polystyrene beads manufacturing method characterized in that Flame retardant polystyrene beads prepared by claim 15 Claim 17 was abandoned upon payment of a registration fee. 17. A method for producing a flame retardant styrofoam by foaming, molding and fusion process on a flame retardant polystyrene bead according to claim 16 Claim 18 was abandoned upon payment of a set-up fee. Flame retardant styrofoam prepared by claim 17