KR20160072411A - Expandable polystyrene beads having excellent thermal insulation, flame retardancy and good moldability and a method of manufacturing the same - Google Patents

Abstract

The present invention relates to a foaming polyester particle having molding properties, insulation, and flame retardance and to a method for producing the same. More specifically, the present invention relates to a foaming polyester particle in which an insulating material, a flame retardant material, and a bubble adjusting agent are evenly dispersed and to a method for producing the same. A method for producing a foaming polyester particle comprises the steps of: (1) producing a mixed composition by mixing an insulating material, a flame retardant material, and a bubble adjusting agent in a styrene-based resin; (2) obtaining an extruded pellet having uniform particles by dissolving and extruding the composition; and (3) suspending the extruded pellet in ultrapure water having a suspending agent existing therein, adding a flame retardant assisting agent therein, and adding and dipping C4-C6 hydrocarbon therein. A foaming body produced from a foaming polystyrene-based particle according to the present invention may be excellently fused, has insulation functions of two bead schemes of KS M 3808, and exhibits excellent flame retardant functions in which autonomous-extinguishing flame retardance is ensured and the amount of discharged heat is low when there is a fire. Moreover, when a foaming body produced from a foaming polystyrene-based particle according to the present invention is used as a core material of a sandwich panel, the standards of a flame retardant material (flame retardance grade 3) may be satisfied on the basis of a scheme for testing flame retardance of a building internal finishing material, which has been established by the Ministry of Land, Transport and Maritime Affairs.

Description

FIELD OF THE INVENTION [0001] The present invention relates to expanded polystyrene particles having excellent moldability and excellent heat insulation performance and flame retardant performance, and a method of manufacturing the same,

The present invention relates to expandable polystyrene particles having excellent moldability and excellent heat insulating performance and flame retardancy, and a process for producing the same. More particularly, the present invention relates to a foamed polystyrene particle in which a heat insulating material, a flame retardant substance, and a foam modifier are uniformly dispersed, and a method for producing the same. The foam prepared from the expandable polystyrene-based particles of the present invention has two kinds of bead methods of KS M 3808 And has an effect of exhibiting excellent flame retardant performance as well as self-extinguishing flame retardance and low heat release amount in case of fire.

When the foam produced from the expandable polystyrene-based particles of the present invention is used as a core of a sandwich panel, the specification of the flame retardant material (flame retardant grade 3) can be satisfied based on the flame resistance test method of the interior finishing material of the building of the Ministry of Land, Transport and Maritime Affairs.

Foams made from expandable polystyrene-based particles are widely used as building materials due to their excellent heat insulation performance and easy workability, but they are disadvantageous in that flame retardancy is lowered than inorganic insulation materials such as glass fiber and gypsum board. More than 70% of the domestic foam polystyrene particles are used as general building insulation materials or sandwich panels. Recently, buildings designed with sandwich panels have been limited in use due to frequent fire and danger. In order to apply foaming polystyrene foam, flame retardant materials ) Flame retardancy is required.

There have been various attempts to improve the flame retardant performance of the foamable polystyrene foam. In the introduction of the flame retardant additive, there have been proposed a method of coating the flame retardant composition on expandable polystyrene particles or foam lips, a flame retardant substance in the suspension polymerization process of producing expandable polystyrene particles Is known.

Korean Patent No. 1093995 discloses a method for producing a flame retardant composition excellent in the anti-fuming property by using a metal hydroxide such as aluminum hydroxide, a non-metal hydroxide, expanded graphite, a curing agent, and a liquid polyvinyl acetate resin adhesive, And then the mixture is poured into a blender and rotated at a high speed to produce expandable polystyrene particles coated with a flame retardant composition. When the surface of the foamed polystyrene particles is physically coated with a flame retardant agent, the flame retardant agent is easily removed in the subsequent foaming and molding processes for producing the foam, so that the effect of improving the flame retardancy of the final product foamed article is small. Further, in addition to the conventional method of producing polystyrene foam, a flame retardant composition requires a process such as coating, drying, and the like, so that the workability is lowered and the mechanical properties such as strength deterioration due to degradation of fusion- It has the drawbacks of falling.

In another method, Korean Patent No. 573636 discloses a method for producing expandable polystyrene particles containing graphite particles by polymerizing styrene in an aqueous suspension in the presence of expanded graphite. In the method of producing expandable polystyrene particles by the suspension polymerization method, when the flame retardant additive is added in excess of 10 parts by weight or more in order to improve the flame retardancy, the dispersion stability is impaired and it is difficult to form the particles. It also leads to a broad particle size distribution after polymerization and leads to the generation of unacceptable Grade and Off Grade, which requires further processing of the stepwise fractionation work through the separator to obtain the authentic product .

In order to improve the heat insulating performance and the flame retardant performance of the expandable polystyrene particles as described above, additives such as a flame retardant are introduced in an amount of 10 parts by weight or more. If a large amount of additives is introduced into expandable polystyrene particles or pre-expanded lip particles, there is a problem that the fusion of the molded product is poor during the production of expandable polystyrene foam, resulting in deterioration of mechanical strength and deterioration of heat insulation performance and flame retardancy.

Korean Patent Registration No. 10-1093995 Korean Patent Registration No. 10-0573636

Disclosed is a foamed polystyrene particle in which a heat insulating substance, a flame retardant substance and a foam modifier are uniformly dispersed, and a method for producing the same.

The present invention also provides foamed polystyrene particles which are uniformly dispersed in a particle of a heat insulating material and a flame retardant and can be obtained at a high yield without a separate fractionation work through a separator and a method for producing the same.

The present invention also provides foamed polystyrene particles excellent in heat insulation and flame retardancy and capable of producing products as existing facilities without additional processes other than the conventional foaming and molding processes in the production of expandable polystyrene foam, and a method for producing the same.

The present invention also provides foamable polystyrene particles having two kinds of bead methods of KS M 3808 and capable of producing self-extinguishing flame retardant as well as a foam having an excellent flame retardancy with a low heat release amount in the case of fire, and a process for producing the same will be.

The present invention also provides a foamed polystyrene foam having excellent heat insulation performance and flame retardant performance using the expanded polystyrene particles produced by the present invention and having excellent fusion of molded articles.

The present invention also provides a core material for a sandwich panel corresponding to a flame retardant material (flame retardant grade 3) using the expandable polystyrene particles produced by the present invention.

According to the present invention, there is provided a process for preparing a mixed composition by mixing a heat insulating material, a flame retardant substance and a foam control agent with a styrenic resin to obtain a uniform particle pellet by melting and extruding the composition, suspending the pellet in water, And C4 ~ C6 hydrocarbons were added to the mixture to impregnate the foamed polystyrene particles with the foamed polystyrene particles.

The expandable polystyrene particles having excellent moldability and excellent heat insulation performance and flame retardant performance of the present invention are prepared by dispersing 20 to 40 parts by weight of a heat insulating substance, a flame retardant substance and a foam modifier in polystyrene particles evenly, No additional process is required.

Further, the foam prepared from the expandable polystyrene particles of the present invention can be produced as it is without any additional processing steps, and can be manufactured as it is with excellent fusion strength of the molded product and has high thermal insulation performance of two kinds of bead method of KS M 3808 and self- In addition, it has an effect of exhibiting excellent flame retardant performance with a low emission calorific value in case of fire.

Also, when the foam prepared from the expandable polystyrene particles of the present invention is used as a core material of a sandwich panel, there is an effect of exhibiting a flame retardancy performance corresponding to a flame retardant material (flame retardant grade 3) according to the flame retardancy test method of the interior finishing materials of buildings of the Ministry of Land, Transport and Maritime Affairs.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a photograph of a foam surface prepared from expandable polystyrene particles produced by the method according to Example 1 of the present invention. FIG.
2 is a photograph of a surface of a foam prepared from expandable polystyrene particles produced by the method according to Example 2 of the present invention.
3 is a photograph of a foam surface prepared from expandable polystyrene particles prepared by the method according to Comparative Example 1 of the present invention.
4 is a photograph of a foam surface prepared from expandable polystyrene particles prepared by the method according to Comparative Example 2 of the present invention.

The present invention relates to expandable polystyrene particles having excellent moldability and excellent heat insulating performance and flame retardancy, and a process for producing the same. The expandable polystyrene particles of the present invention are characterized in that impression graphite for improving the heat insulating performance, a flame retardant for enhancing the flame retardancy, and talc, which is a bubble regulator for refining the foamed lip cells, are well dispersed.

The production of the expandable polystyrene particles of the present invention comprises the steps of: (1) mixing a heat insulating material, a flame retardant substance and a bubble regulating agent in a styrene resin to prepare a mixed composition; (2) melting and extruding the composition to obtain a uniform particle extruded pellet; (3) suspending the extruded pellets in ultrapure water in which the suspension is present, adding a flame retardant aid, and then injecting and impregnating C4 to C6 hydrocarbons.

In the practice of the present invention, in the step of obtaining extruded pellets of suspendable and uniform particles, there is no particular limitation on the extruder, and the use of an underwater pelletizer or a water-cooled die-face pelletizer An extruder capable of suspending pellets of uniform particles can be used. The pellets of suspendable, homogeneous particles produced by this extrusion are generally less than 2 mm in size and can be obtained in high yield of particles of the desired size. The extrusion temperature is 130 to 260 ° C, preferably 150 to 230 ° C.

In the practice of the present invention, the styrene series resin may be styrene; Alkylstyrenes (e.g., ethylstyrene, dimethylstyrene, para-methylstyrene); Alpha-alkylstyrenes (e.g., alpha-methylstyrene, alpha-ethylstyrene, alpha-propylstyrene, alpha-butylstyrene); Halogenated styrenes (e.g., chlorostyrene, bromostyrene); And vinyltoluene, and is a polymer or copolymer of a styrenic monomer, and examples of the monomer copolymerizable with the styrenic monomer include acrylonitrile, butadiene, alkyl acrylate (e.g., methyl acrylate, alkyl methacrylate Methacrylate)), isobutylene, vinyl chloride, isoprene, and mixtures thereof. In a preferred embodiment of the present invention, the styrene resin is a polystyrene resin having a weight average molecular weight of 180,000 to 400,000 g / mol.

In the practice of the present invention, the heat insulating performance material to be mixed with the polystyrene resin is graphite, and graphite can be natural graphite or synthetic graphite. The particle size is preferably 1 to 50 mu m, particularly preferably 2 to 10 mu m Do. In the present invention, the content of graphite is preferably 0.05 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, based on the polystyrene resin.

In the practice of the present invention, the flame retardant used in the preparation of the mixed composition may be any conventionally used flame retardant without any particular limitation. For example, expanded graphite or metal hydroxide such as aluminum hydroxide or magnesium hydroxide and phosphorus flame retardants such as red phosphorus, ammonium polyphosphate, diphenyl phosphate, triphenyl phosphate, etc., bromine-based flame retardants such as hexabromocyclododecane and decabromodiphenylethane Flame retardants are used. Also, melamine-based flame retardants such as melamine, melamine cyanurate, and melamine phosphate and boron-based flame retardants such as zinc borate are used. One or a combination of two or more selected from the flame retardants may be used. Expanded graphite and decabromodiphenylethane were used in the examples of the present invention. In general, the particle size of the expanded graphite is preferably 20 to 500 μm, more preferably 50 to 300 μm. If the particle size of the expanded graphite is small, flame-retardant performance may be deteriorated due to low heat-induced wastewater drainage. If the particle size is large, the extrusion does not progress smoothly, and the cell of the prefoamed lip made of expandable polystyrene particles becomes large As the number of open cells increases, there is a disadvantage in that the fusion of molded articles of the foam is lowered and the mechanical strength is lowered. The content of the expanded graphite added is preferably 0.05 to 50 parts by weight, more preferably 0.5 to 30 parts by weight, based on the polystyrene resin. If the amount of the expanded graphite is too small, the flame retardant effect is insufficient. If the excessive amount of expanded graphite is added, the extrusion does not progress smoothly. In addition, the foaming property of the expandable polystyrene particles is lowered, have.

In the practice of the present invention, when the expanded polystyrene particles into which expandable graphite having a size of 20 탆 or more is pre-expanded, the expanded graphite tears the cell walls of the foamed lips to increase the open cell content, A large number of conflicting bubbles having a diameter of 500 to 1,500 탆 in the lip are present. The foams produced from such foamed foams may suffer from poor fusion of the molded articles, resulting in deterioration of mechanical strength and heat insulation performance. Therefore, in the present invention, a bubble regulator is used to improve the fusion, mechanical strength and thermal insulation of a molded article by making small and uniform bubbles of foamed lips during the production of foams. Talc, polyethylene wax and ethylene bisstearamide, calcium carbonate, Talc, clay, silica, diatomaceous earth, citric acid and sodium bicarbonate may be used, and it is preferable to use 0.05 to 10 parts by weight with respect to 100 parts by weight of the polystyrene resin.

In the practice of the present invention, the pellets containing the heat insulating material, the flame retardant substance and the air bubble modifier are suspended in ultrapure water in the presence of a suspension, the flame retardant aid is added, and C4 to C6 hydrocarbons are injected with a blowing agent, The suspending agent and the foaming agent may be those used for usual foam polystyrene polymerization.

In the present invention, 0.01 to 1.0 part by weight of sodium pyrophosphate and 0.01 to 1.0 part by weight of magnesium chloride are mixed with 100 parts by weight of ultrapure water by stirring. .

As the surfactant in the suspension, sodium laurylsulfonate, sodium alkylbenzenesulfonate, sodium oleinsulfonate and the like are used. In the present invention, 0.01-1.0 parts by weight of sodium alkylbenzenesulfonate is used for 100 parts by weight of ultrapure water.

Dicumylperoxide was used as the flame retardant aid and added with a bromine-based flame retardant, so that the bromine of the bromine-based flame retardant was quickly released during combustion, thereby facilitating the flame retarding effect to be exhibited quickly. In addition, there is an effect that the chain of the polystyrene resin is cut off, and the molecular weight of the final product is slightly reduced, thereby improving the fusion of the molded product in the production of the foam. In the present invention, the content of the added dicumyl peroxide is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 2 parts by weight, based on the polystyrene resin. When the amount is too large, the molecular weight of the final product is much lowered, which may cause a problem of shrinkage of the molded article during the production of the foam.

Examples of the foaming agent include butane, i-butane, n-pentane, i-pentane, neo-pentane, cyclopentane and halogenated hydrocarbons. Examples of the foaming agents C4 to C6 used in the production of general expandable polystyrene include butane 4 to 15 parts by weight based on 100 parts by weight of polystyrene particles are used.

In the practice of the present invention, the method of suspending the extruded pellets in ultrapure water in which the suspension is present, introducing the flame retardant aid, and then impregnating the extruded pellets by introducing C4 to C6 hydrocarbons is as follows. The extruded pellets including an ultrapure water, a dispersant, a surfactant, a heat insulating substance, a flame retardant substance and a foam controlling agent are put into a high pressure reactor to maintain dispersion. When the dispersion was stabilized, the flame-retardant aid, dicumyl peroxide, was added, the inlet of the reactor was closed, and the temperature of the reactor was raised to between 100 and 130 ° C. When the temperature stabilized, the blowing agent was introduced into the reactor under nitrogen pressure and impregnation was carried out for 5 hours while maintaining the final reactor pressure at 13 kgf / cm < 2 >. The product was then cooled to below 30 < 0 > C and the product was discharged from the reactor. The product was washed with water, dried, and applied with a blending agent used in ordinary foam polystyrene particle production. The foaming and shaping of the foamed polystyrene particles thus obtained can be carried out under usual foaming and molding conditions, and there is no particular limitation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments and comparative examples of the present invention will be described in detail with reference to the accompanying drawings. It is to be understood that the same is by way of illustration and example only and is not to be construed as limiting the present invention But does not mean that the technical idea and scope of the present invention are limited.

≪ Example 1 > 13 parts by weight of expanded graphite, a flame retardant aid,

4 parts by weight of graphite (Wad99: WF99-5) as 100 parts by weight of a polystyrene resin (Kumho Petrochemical GP 150), 13 parts by weight of expanded graphite (LS-Chem; CX-80) 5 parts by weight of decabromodiphenylethane (ALBEMARLE; SAYTEX 8010) and 1 part by weight of talc (KOCH) as a cell regulator were mixed and melted and kneaded at 190 ° C in a twin-screw extruder to obtain a Resin particles were obtained. A dispersion was prepared by dissolving 0.15 kg of sodium pyrophosphate (Youngjin), 0.4 kg of magnesium chloride (Seowon Chemical 30% aqueous solution) and 0.2 kg of surfactant alkylbenzenesulfonate (LGH Health) in 3 kg of ultrapure water as a dispersing agent. 62 kg of ultrapure water and the prepared dispersion were charged into a 100 L reactor and stirred, and 20 kg of the resin particles were added. When the dispersion stabilized, 0.1 kg of dicumyl peroxide (MyungJin Polychem) was added as a flame retardant aid. Subsequently, the inlet of the reactor was closed and the temperature of the reactor was elevated to 110 DEG C. When the internal temperature of the reactor was stabilized, 2 kg of a foaming agent (n-pentane; Duksan Chemical Co.) was introduced into the reactor under a nitrogen pressure. cm < 2 > for 5 hours. Thereafter, the internal temperature of the reactor was cooled to 30 DEG C or less, and the product was discharged from the reactor. The product was washed with water and dried, and then a blending agent used for preparing ordinary expandable polystyrene particles was applied, foamed, and molded, and the physical properties were evaluated.

≪ Example 2 > 13 parts by weight of expanded graphite,

4 parts by weight of graphite (Wad99: WF99-5) as 100 parts by weight of a polystyrene resin (Kumho Petrochemical GP 150), 13 parts by weight of expanded graphite (LS-Chem; CX-80) And 5 parts by weight of decabromodiphenylethane (ALBEMARLE; SAYTEX 8010) were added and mixed. The mixture composition was melt-kneaded in a twin-screw extruder at 190 캜 to obtain resin particles having an average diameter of 2.0 mm. The following process was carried out in the same manner as in Example 1 to prepare expandable polystyrene particles.

≪ Comparative Example 1 > 13 parts by weight of expanded graphite

4 parts by weight of graphite (Wad99: WF99-5) as 100 parts by weight of a polystyrene resin (Kumho Petrochemical GP 150), 13 parts by weight of expanded graphite (LS-Chem; CX-80) And 5 parts by weight of decabromodiphenylethane (ALBEMARLE; SAYTEX 8010) were added and mixed. The mixture composition was melt-kneaded in a twin-screw extruder at 190 캜 to obtain resin particles having an average diameter of 2.0 mm. 0.1 kg of sodium pyrophosphate (Youngjin), 0.4 kg of magnesium chloride (Seowon Chemical 30% aqueous solution) and 0.2 kg of surfactant (alkylbenzenesulfonate; LGH Health) were dissolved in 3 kg of ultrapure water to prepare a dispersion. 62 kg of ultrapure water and the prepared dispersion were charged into a 100 L reactor and stirred, and 20 kg of the resin particles were added. When the dispersion stabilizes, the reactor inlet is closed and the reactor temperature is raised to 110 ° C. When the internal temperature of the reactor is stabilized, 2 kg of a foaming agent (n-pentane; Duksan Chemical Co.) is introduced into the reactor under nitrogen pressure. 13 kgf / cm < 2 > for 5 hours. Thereafter, the internal temperature of the reactor was cooled to 30 DEG C or less, and the product was discharged from the reactor. The product was washed with water and dried, and then a blending agent used for preparing ordinary expandable polystyrene particles was applied, foamed, and molded, and the physical properties were evaluated.

≪ Comparative Example 2 > 20 parts by weight of expanded graphite

4 parts by weight of graphite (Wad9900: WF99-5) and 20 parts by weight of expanded graphite (LS-Chem; CX-80) as a flame retardant were added to 100 parts by weight of a polystyrene resin The resulting mixture was melt-kneaded at 190 DEG C in a twin-screw extruder to obtain resin particles having an average diameter of 2.0 mm. 0.1 kg of sodium pyrophosphate (Youngjin), 0.4 kg of magnesium chloride (Seowon Chemical 30% aqueous solution) and 0.2 kg of surfactant (alkylbenzenesulfonate; LGH Health) were dissolved in 3 kg of ultrapure water to prepare a dispersion. 62 kg of ultrapure water and the prepared dispersion were charged into a 100 L reactor and stirred, and 20 kg of the resin particles were added. When the dispersion stabilizes, the reactor inlet is closed and the reactor temperature is raised to 110 ° C. When the internal temperature of the reactor is stabilized, 2 kg of a foaming agent (n-pentane; Duksan Chemical Co.) is introduced into the reactor under nitrogen pressure. 13 kgf / cm < 2 > for 5 hours. Thereafter, the internal temperature of the reactor was cooled to 30 DEG C or less, and the product was discharged from the reactor. The product was washed with water and dried, and then a blending agent used for preparing ordinary expandable polystyrene particles was applied, foamed, and molded, and the physical properties were evaluated.

Comparative Example 3 Production of expandable polystyrene particles using a general suspension polymerization method

40 kg of styrene monomer (SK), 0.4 kg of hexabromocyclododecane (GLC; CD75PTM), which is a flame retardant, and 0.2 g of a flame retardant additive 0.14 kg of benzoyl peroxide (Hansol Chemical), 0.06 kg of t-butyl peroxybenzoate (Hosung Chemex), 0.04 kg of polyethylene wax (BAKER HUGHES) as a cell regulator Respectively. The internal temperature of the reactor was raised to 90 캜 and maintained for 6.5 hours. Then, the inlet of the reactor was closed, and the temperature was gradually raised from 90 DEG C to 115 DEG C for 1 hour and 30 minutes. When the reactor temperature stabilized at 115 ° C, 3 kg of pentane (SK) was charged to the reactor under nitrogen pressure and impregnation was carried out for 5 hours while maintaining the final reactor pressure at 13 kgf / cm 2. The product was then cooled to below 30 < 0 > C and the product was discharged from the reactor. The product was washed with water, dried, and applied with a blending agent used in ordinary foam polystyrene particle production, and subjected to foaming, molding and physical property evaluation.

Table 1 below shows the properties of the test pieces produced by the above examples. The method for evaluation is as follows.

(1) Relative Molecular Weight: Measured by Gel Permeation Chromatography (GPC).

(2) Cell Size (탆): The foamed polystyrene particles were cut and the diameter of the cell was measured with a digital micro-microscope.

(3) 5 minutes foaming property (fold): When foaming was carried out at a steam pressure of 0.3 kgf / cm 2 for 5 minutes, the foaming drainage was measured.

(4) Thermal conductivity (W / mK): Measured according to the initial thermal conductivity measurement method of expanded polystyrene (PS) insulation disclosed in Korean Industrial Standard KS M 3808 with a sample density of 24 kg / m 3.

(5) Surface spreadability (fusion): The surface of the foam made of expandable polystyrene particles was observed, and the degree of smoothness was expressed as upper, middle, and lower without a space between the foam lips.

(6) Total heat release rate (MJ / ㎡): The flame retardancy test was conducted according to KS F ISO 5660-1, the flame retardant performance test method of building finishing materials, and the total heat released after heating for 5 minutes was measured. For flame retardant materials (flame retardant grade 3), the total heat release rate is 8 MJ / ㎡ or less.

(7) Maximum heat release rate (㎾ / ㎡): The flame retardancy test was carried out in accordance with KS F ISO 5660-1, the flame retardant performance test method of building finishing materials, and the maximum heat release rate after heating for 5 minutes was measured.

(8) 200 kW / ㎡ continuous overtime (sec): KS F ISO

5660-1, and the time at which the heat release rate continuously exceeds 200 kW / m < 2 > during heating for 5 minutes was measured. In the case of the flame retardant material (flame retardant grade 3), the time exceeding 200 kW / m 2 continuously is 10 seconds or less.

(9) Gas Hazard Test: Flame retardancy test was carried out according to KS F 2271, a flame retardant performance test method of building finishing materials, and the average behavioral downtime of rats was measured. In the case of flame retardant materials (flame retardant grade 3), the average behavioral downtime of the rats is more than 9 minutes.

Property table Item Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Suzy
(Parts by weight)
polystyrene 100 100 100 100 Styrene monomer 100 Adiabatic material
(Parts by weight) black smoke 4 4 4 4 0 Flammability
matter
(Parts by weight)


Expanded graphite 13 13 13 20 Decablo
Diphenylethane 5 5 5 Dicyclohexyl oxide 0.6 0.6 One Hexabromo
Cyclododecane One bubble
Modulator
(Parts by weight)
Talc One Polyethylene wax 0.1 Relative molecular weight 25.7 million 25.5 million 27.2 million 26.8 million 25.9 million Bubble size (㎛) 150-500 300-1,000 300-1,000 800-1,500 150-200 5 minutes foaming (times) 62 60 55 40 65 Thermal conductivity (W / mK) 0.032 0.033 0.034 0.035 0.037 Surface spreadability (fusion) Prize Prize medium Ha Prize Core core itself

Flame retardant test
(KS F ISO 5660-1,
5 minutes)
Total emission
calorie
(MJ / m 2)
20.01 20.36 20.57 16.17 60.89 Maximum column
Release rate
(㎾ / ㎡)
288.46 279.52 269.00 217.87 405.02
Sandwich
panel
making

Flame retardant test
(KS F ISO 5660-1,
5 minutes)
Total emission
calorie
(MJ / m 2)
3.0 3.3 Not measured


200 kW / ㎡ continuous overtime (sec) 0 0 Gas hazard
(KS F 2271) Mean behavioral downtime of rats 12 minutes 07 seconds 13 minutes 28 seconds

From the results shown in the above Table 1, the expanded polystyrene particles prepared by the general suspension polymerization method of Comparative Example 3 had a thermal conductivity of 0.037 W / mK at a density of 24 kg / m 3, but the thermal conductivity was lower in the case of the graphite- Respectively. In addition, in Comparative Example 3, hexabromocyclododecane, which is a flame retardant generally used in the production of expandable polystyrene particles, was added. As a result of the flame retardant test of KS F ISO 5660-1, the total heat release amount was 60.89 MJ / , And the maximum heat release rate was 405.02 ㎾ / ㎡. As shown in the examples, when the expanded graphite was added as the flame retardant, the total heat release rate and the maximum heat release rate were lowered and the flame retardancy was improved remarkably.

In Comparative Example 2, when 20 parts by weight of expanded graphite was introduced, the total heat release rate and the maximum heat release rate were low. However, as shown in FIG. 4, when the fusion of the foam was poor and the cell size was large, I could see the fall.

In Comparative Example 1, the amount of expanded graphite was reduced, but the addition of a bromine-based flame retardant supplemented the flame retardancy. As shown in FIG. 3, the fusion of the foam was improved as shown in FIG. 3, and thus the heat conductivity of the two kinds of bead methods as a heat insulating material in the domestic 'A' group was 0.34 W / mK or less. Satisfaction.

In the case of Example 2, the addition of dicumyl peroxide as a flame retardant aid, which is a flame retardant aid, slightly lowered the molecular weight and increased the foamability. As shown in FIG. 2, the fusion of the foam was improved and the thermal conductivity was lowered .

In the case of Example 1, the cell size was small and stabilized, foamability was increased, and thermal conductivity was lowered by introducing talc, which is a bubble regulator, in comparison with Example 2.

In order to exhibit excellent flame retardancy and heat insulation performance through the present invention, additives were prepared by uniformly dispersing the inside of expandable polystyrene particles. In addition, the disadvantages of low foaming properties, cell confusion, and defective fusion of molded articles, which are caused by the introduction of many additives, can be improved by introducing a flame retardant auxiliary agent and a foam controlling agent to make bubbles small and uniform, It is confirmed that the fusion bonding and the heat insulating performance can be improved.

Further, the foam prepared from the expandable polystyrene particles of the present invention exhibits excellent flame retardant performance with low heat release amount in case of fire as well as thermal insulation performance and self-extinguishing flame of two kinds of bead method of KS M 3808, and the produced foam is used as core material of sandwich panel When used, the flame retardant performance corresponding to the flame retardant material (flame retardant grade 3) was shown according to the flame retardancy test method of the interior finishing material of the building of the Ministry of Land, Transport and Maritime Affairs.

Those skilled in the art will recognize that modifications of the invention are possible without departing from the scope and spirit of the invention, and the scope of the invention is determined by the claims that follow.

Claims (11)

(1) preparing a mixed composition by mixing a styrenic resin with a heat insulating material, a flame retardant, and a bubble controlling agent; (2) melting and extruding the composition to obtain a uniform particle extruded pellet; (3) suspending the extruded pellets in ultrapure water in the presence of a suspension, introducing a flame retardant aid, and then impregnating the foamed polystyrene particles by introducing C4 to C6 hydrocarbons as a blowing agent.
The method according to claim 1,
Wherein the styrene resin is a polystyrene resin and has a weight average molecular weight of 180,000 to 400,000 g / mol.
The method according to claim 1,
Wherein the heat insulating material comprises 0.05 to 20 parts by weight of graphite per 100 parts by weight of the styrene resin.
The method according to claim 1,
The flame retardant may be one or more selected from the group consisting of expanded graphite, metal hydroxide, phosphorus flame retardant, melamine flame retardant, boron flame retardant and halogen flame retardant, and 0.05 to 50 parts by weight ≪ / RTI >
5. The method of claim 4,
Wherein the expanded graphite has a particle size of 20 to 500 탆.
The method according to claim 1,
The bubbling agent is selected from the group consisting of talc, polyethylene wax and ethylene bisstearamide, calcium carbonate, talc, clay, silica, diatomaceous earth, citric acid and sodium bicarbonate,
Is 0.05 to 10 parts by weight based on 100 parts by weight of the styrene-based resin.
The method according to claim 1,
As the flame-retardant auxiliary, dicumyl peroxide is used,
Is 0.05 to 10 parts by weight based on 100 parts by weight of the styrene resin.
The method according to claim 1,
Wherein the foaming agent is 4 to 15 parts by weight based on 100 parts by weight of the foamable styrene resin.
6. A process for the preparation of a compound according to claim 1,
A foamed polystyrene particle characterized in that a heat insulating material, a flame retardant substance and a foam control agent are uniformly dispersed.
A foam made of the expandable polystyrene particles of claim 9.
A sandwich panel fabricated from the foam of claim 10 as core.

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