KR20200002136A - Method for preparing expandable aromatic vinyl resin bead - Google Patents

Abstract

The present invention relates to a method for manufacturing expandable aromatic vinyl resin particles. The manufacturing method comprises steps of: manufacturing a suspension by mixing a dispersoid containing aromatic vinyl-based monomer, an initiator, a nucleating agent, a flame retardant, and a heat insulating material with a dispersion medium containing water, tricalcium phosphate, and potassium carbonate; manufacturing aromatic vinyl-based resin particles by conducting reaction of the suspension; and manufacturing expandable aromatic vinyl-based resin particles by introducing a foaming agent to the aromatic vinyl-based resin particles. The method for manufacturing expandable aromatic vinyl resin particles can manufacture expandable aromatic vinyl-based resin particles which have excellent flame retardancy, insulation properties, etc. and have controlled particle diameters.

Description

Method for producing foamable aromatic vinyl resin particles {METHOD FOR PREPARING EXPANDABLE AROMATIC VINYL RESIN BEAD}

The present invention relates to a method for producing expandable aromatic vinyl resin particles. More specifically, the present invention relates to a method for producing expandable aromatic vinyl resin particles having excellent flame retardancy, heat insulating property, and the like and having a controlled particle diameter.

Foamable aromatic vinyl-based resin particles are resins prepared to be foamed when the foaming agent diffuses and volatilizes to outside air when heated with steam or the like. After pre-expanding to a desired density, the foam is filled into a mold and heated and fused to form a molded article (foaming). Molded body). The molded article manufactured as described above is excellent in high strength, light weight, cushioning property, waterproofness, heat retention, heat insulation, and the like, and is used in various fields such as packaging materials for household appliances, agricultural products boxes, rich people, and thermal insulation materials for building materials.

Typically, the expandable aromatic vinyl resin particles are added to the reactor by suspension polymerization, water, an aromatic vinyl monomer, a polymerization initiator and a suitable suspension stabilizer, are dispersed by stirring, and then heated up to form spherical aromatic vinyl resin particles. It can be prepared and impregnated with a blowing agent to finally obtain spherical expandable aromatic vinyl resin particles.

However, when graphite, carbon black, alumina, or the like is used as the heat insulating material in the production of the expandable aromatic vinyl resin particles, the particle size distribution of the aromatic vinyl resin particles is broadly formed, so that the particle size control and homogeneous particle size distribution can be achieved. There is a problem that cannot be obtained.

Therefore, there is a need for development of a method capable of producing expanded aromatic vinyl-based resin particles having excellent flame retardancy, thermal insulation, etc., and having a uniform particle size distribution and having a controlled particle size.

Background art of the present invention is disclosed in US Patent No. 6,130,265 and the like.

An object of the present invention is to provide a method for producing expandable aromatic vinyl resin particles which are excellent in flame retardancy, heat insulation, etc., and can produce expandable aromatic vinyl resin particles having a controlled particle diameter.

Another object of the present invention is to provide an expandable aromatic vinyl-based resin particle formed from the above production method and a foamed molded article thereof.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to a method for producing expandable aromatic vinyl resin particles. The preparation method includes preparing a suspension by mixing a dispersion medium including water, tricalcium phosphate, and potassium carbonate with a dispersion including an aromatic vinyl monomer, an initiator, a nucleating agent, a flame retardant, and a heat insulating material; Reacting the suspension to prepare aromatic vinyl resin particles; And it is characterized in that it comprises the step of preparing a foamable aromatic vinyl resin particles by adding a blowing agent to the aromatic vinyl resin particles.

In one embodiment, the dispersoid comprises 100 parts by weight of an aromatic vinyl monomer, 0.3 to 1.2 parts by weight of initiator, 0.2 to 1.0 parts by weight of nucleating agent, 0.3 to 1.5 parts by weight of flame retardant, and 2.0 to 6.0 parts by weight of insulating material, and the dispersion medium 100 parts by weight of water, 0.2 to 1.5 parts by weight of tricalcium phosphate, and 0.04 to 0.2 parts by weight of potassium carbonate, wherein the weight ratio of the tricalcium phosphate and the potassium carbonate is 4: 1 to 11: 1, and the dispersoid and The weight ratio of the dispersion medium may be 1: 0.8 to 1: 1.2.

In embodiments, the weight ratio of the heat insulating material and the tricalcium phosphate may be 1: 0.1 to 1: 0.3.

In an embodiment, the initiator comprises benzoyl peroxide, dicumyl peroxide, tertiary-amyl (2-ethylhexyl) monoperoxycarbonate, tertiary-butyl (2-ethylhexyl) monoperoxycarbonate, and dibenzoyl peroxide. It may include one or more of the oxides.

In embodiments, the nucleating agent may be a polyolefin wax.

In an embodiment, the flame retardant is hexabromo cyclo dodecane, 1,3-butane bromine benzene ethyl polymer, and 1,1 '-(isopropylidene) bis [3,5-dibromo-4- (2,3-dibromo-2-methylpropyl) benzene] may be included.

In embodiments, the heat insulating material may include one or more of graphite, carbon black, and alumina.

In embodiments, the dispersion medium may have an electrical conductivity of 1,700 to 10,000 μs / cm measured according to ASTM D1125.

In embodiments, the reaction may be carried out at 80 to 130 ℃.

In an embodiment, the expandable aromatic vinyl-based resin particles may have an average particle diameter of 0.35 to 2.0 mm measured using a sieve of ASTM E-11 standard.

In embodiments, the expandable aromatic vinyl-based resin particles may be from 60 to 95% by weight of the particles having a particle diameter of 0.5 to 1.2 mm in 100% by weight of the total particles.

In embodiments, the expandable aromatic vinyl-based resin particles may have a thermal conductivity of 0.031 to 0.035 W / m · K measured based on KS M 3808.

In an embodiment, the expandable aromatic vinyl resin particles may have a burning length of 40 to 55 mm and a burning time of 3 to 11 seconds for a 150 × 50 × 12 mm size specimen measured according to KS M ISO 9772.

Another aspect of the present invention relates to expandable aromatic vinyl resin particles. The expandable aromatic vinyl resin particle is characterized in that it is produced by the above production method.

Another aspect of the present invention relates to a foamed molded article. The foamed molded article is characterized by being formed by pre-expanding the expandable aromatic vinyl resin particles in a mold, heating and fusion to form a mold.

The present invention provides a method for producing expandable aromatic vinyl resin particles having excellent flame retardancy, thermal insulation, and the like, and capable of producing expandable aromatic vinyl resin particles having a controlled particle diameter, expandable aromatic vinyl resin particles formed therefrom, and foamed molded products thereof. Provided has the effect of the invention.

Hereinafter, the present invention will be described in detail.

Foamable aromatic vinyl resin particles according to the present invention comprises the steps of preparing a suspension by mixing a specific dispersion medium to a specific dispersion; Reacting the suspension to prepare aromatic vinyl resin particles; And preparing a foamable aromatic vinyl resin particle by adding a blowing agent to the aromatic vinyl resin particle.

The dispersoid of the present invention is (A) an aromatic vinyl monomer; (B) an initiator; (C) a nucleating agent; (D) flame retardants; And (E) a heat insulating material.

(A) Aromatic vinyl monomer

The aromatic vinyl monomer according to one embodiment of the present invention is polymerized to form an aromatic vinyl resin contained in ordinary expandable aromatic vinyl resin particles.

In embodiments, the aromatic vinyl monomers include styrene, α-methylstyrene, β-methylstyrene, p-methylstyrene, pt-butylstyrene, ethyl styrene, vinyl xylene, monochlorostyrene, dichlorostyrene, dibromostyrene , Vinylnaphthalene, mixtures thereof and the like can be exemplified. For example, styrene, α-methylstyrene, mixtures thereof, and the like can be used.

In embodiments, the aromatic vinyl resin may have a weight average molecular weight of 200,000 to 400,000 g / mol, for example 250,000 to 350,000 g / mol, as measured by gel permeation chromatography (GPC). In the above range, the heat-insulating property, flame retardancy, foamability, etc. of the expandable aromatic vinyl resin particles (foamed molded body) may be excellent, and may be advantageous for forming a uniform cell structure.

(B) initiator

Initiator according to an embodiment of the present invention can be used without limitation the initiator used in the suspension polymerization of the thermoplastic resin.

In an embodiment, the initiator comprises benzoyl peroxide, dicumyl peroxide, tertiary-amyl (2-ethylhexyl) monoperoxycarbonate, tertiary-butyl (2-ethylhexyl) monoperoxycarbonate, and dibenzoyl peroxide. It may include one or more of the oxides.

In an embodiment, the initiator may be included in an amount of 0.3 to 1.2 parts by weight, for example, 0.4 to 0.7 parts by weight, based on 100 parts by weight of the aromatic vinyl monomer. When the content of the initiator is less than 0.3 parts by weight, there is a fear that the particles are not dispersed during the preparation of the particles, when the content of the initiator is more than 0.8 parts by weight, the particles are formed in a very fine form, there is a fear that particles of a suitable size can not be obtained from the expandable resin have.

(C) nuclear agent

The nucleating agent according to one embodiment of the present invention is added to the foamed molded article of the expandable aromatic vinyl resin particles to have a uniform cell structure, it may be used polyolefin wax or the like.

In an embodiment, the polyolefin wax may be a polymerized olefin monomer such as ethylene, propylene, isopropylene, butylene, isobutylene, and mixtures thereof, and may be, for example, polyethylene wax polymerized with ethylene.

In embodiments, the polyolefin wax may have a weight average molecular weight of 500 to 3,000 g / mol as measured by gel permeation chromatography (GPC). In the above range, a foamed molded article having a more uniform cell structure can be obtained.

In embodiments, the nucleating agent may be included in an amount of 0.2 to 1.0 parts by weight, for example 0.3 to 0.6 parts by weight, based on 100 parts by weight of the aromatic vinyl monomer. When the content of the nucleating agent is less than 0.2 parts by weight, there is a fear that a uniform cell structure may not be formed, and when the content of the nucleating agent is greater than 1.0 parts by weight, the particle size distribution of the particles may be broadly formed, thereby preventing the particle size control and obtaining a homogeneous particle size distribution. There is.

(D) flame retardant

The flame retardant according to one embodiment of the present invention can improve the flame retardancy of the expandable aromatic vinyl resin particles (foamed molded article) and the like, and can be used without limitation the flame retardant used for ordinary expandable aromatic vinyl resin particles.

In an embodiment, the flame retardant is hexabromo cyclo dodecane, 1,3-butane bromine benzene ethyl polymer, and 1,1 '-(isopropylidene) bis [3,5-dibromo-4- (2,3-dibromo-2-methylpropyl) benzene] may be included.

In embodiments, the flame retardant may be included in 0.3 to 1.5 parts by weight, for example 0.5 to 1.0 parts by weight based on 100 parts by weight of the aromatic vinyl monomer. When the content of the flame retardant is less than 0.3 parts by weight, the flame retardancy of the expandable aromatic vinyl-based resin particles (foamed molded body) may be lowered. When the content of the flame retardant exceeds 1.5 parts by weight, the molecular weight of the expandable aromatic vinyl-based resin may be lowered to form particles ( There exists a possibility that the foamability, cell quality, etc. of a foamed molded object may fall.

(E) insulating material

The heat insulating material according to one embodiment of the present invention is capable of improving the heat insulating property of the expandable aromatic vinyl resin particles (foamed molded article) and the like, and can use the heat insulating material used for ordinary expandable aromatic vinyl resin particles.

In embodiments, the heat insulating material may include at least one of graphite, carbon black, and alumina.

In an embodiment, the heat insulating material may be included in an amount of 2.0 to 6.0 parts by weight, for example 3.0 to 5.0 parts by weight, based on 100 parts by weight of the aromatic vinyl monomer. When the content of the heat insulating material is less than 2.0 parts by weight, there is a fear that the heat insulating properties of the expandable aromatic vinyl resin particles (foamed molded body), etc., may be lowered. Destruction may occur, and the foamability and uniform cell quality of the expandable aromatic vinyl-based resin particles (foamed molded article) may be lowered.

In the dispersion medium of the present invention, when the specific dispersant including the insulating material is applied, the particle size distribution of the aromatic vinyl resin particles is broadly formed, and thus the problem of not obtaining the particle size control and homogeneous particle size distribution can be solved through viscosity control. , (F) water; (G) tricalcium phosphate; And (H) potassium carbonate.

In embodiments, the dispersion medium may have an electrical conductivity of 1,700 to 10,000 μs / cm, for example, 3,000 to 7,000 μs / cm, as measured according to ASTM D1125. Within this range, the dispersion stability of the suspension can be ensured, the particle size of the expandable aromatic vinyl resin particles can be adjusted to a specific range, and a homogeneous particle size distribution can be obtained.

(F) water

Water according to one embodiment of the present invention can be used without limitation, conventional water (ultra pure water, ion-exchanged water, etc.) used as a dispersion medium in suspension polymerization.

(G) tricalcium phosphate

The tricalcium phosphate of the present invention is to adjust the electrical conductivity of the dispersion medium with potassium carbonate, to ensure the dispersion stability of the suspension, to control the particle size of the aromatic vinyl resin particles, and to have a homogeneous particle size distribution.

In an embodiment, the tricalcium phosphate may be included in an amount of 0.2 to 1.5 parts by weight, for example 0.5 to 1.0 parts by weight, based on 100 parts by weight of the water. When the content of the tricalcium phosphate is less than 0.2 parts by weight, when preparing the expandable aromatic vinyl-based resin particles, the suspension-based dispersion may be destroyed. When the content of the tricalcium phosphate exceeds 1.5 parts by weight, the particles are formed in a very fine form to form the expandable resin. There is a fear that particles of a suitable size may not be obtained.

(H) potassium carbonate

The potassium carbonate of the present invention is to adjust the electrical conductivity of the dispersion medium together with the tricalcium phosphate to ensure the dispersion stability of the suspension, to control the particle size of the aromatic vinyl resin particles, and to have a homogeneous particle size distribution.

In embodiments, the potassium carbonate may be included in an amount of 0.04 to 0.2 parts by weight, for example, 0.05 to 0.15 parts by weight, based on 100 parts by weight of the water. When the content of the potassium carbonate is less than 0.04 parts by weight, there is a fear that the particle size distribution is widened, and when the content of the potassium carbonate exceeds 0.2 parts by weight, the suspension-based dispersion may be destroyed during particle production.

In embodiments, the weight ratio (G: H) of the tricalcium phosphate (G) and the potassium carbonate (H) may be 4: 1 to 11: 1, for example, 5: 1 to 10: 1. If the weight ratio is less than 4: 1, the particle size distribution may be widened. If the weight ratio is more than 11: 1, the suspension-based dispersion may be broken during particle production.

The expandable aromatic vinyl resin particles according to one embodiment of the present invention may be prepared by applying a conventional method for producing expandable aromatic vinyl resin particles, except that the specific dispersion and the specific dispersion medium are applied.

Typically, the expandable aromatic vinyl resin particles are prepared by mixing a dispersant and a dispersion medium to prepare a suspension; Reacting the suspension to prepare aromatic vinyl resin particles; And it can be prepared by adding a blowing agent to the aromatic vinyl-based resin particles.

In an embodiment, the expandable aromatic vinyl-based resin particles are mixed with the dispersant to prepare a suspension; Reacting the suspension at 80 to 130 ° C., for example, 90 to 110 ° C. for 1 to 10 hours to produce aromatic vinyl resin particles; And a blowing agent is added to the aromatic vinyl resin particles, it can be prepared by reacting for 1 to 5 hours at 100 to 130 ℃, for example 110 to 130 ℃. The prepared expandable aromatic vinyl resin particles may be subjected to a conventional dehydration and drying process to obtain a final product in the form of particles.

In embodiments, the weight ratio (dispersion: dispersion medium) of the dispersoid and the dispersion medium may be 1: 0.8 to 1: 1.2, for example 1: 0.9 to 1: 1.0. Within this range, it is possible to form a uniform particle size distribution.

In embodiments, the weight ratio (E: G) of the heat insulating material (E) and the tricalcium phosphate (G) may be 1: 0.1 to 1: 0.3, for example, 1: 0.12 to 1: 0.25. In this range, the suspension dispersion can be maintained well.

In a specific embodiment, the blowing agent may be a blowing agent used for ordinary expandable aromatic vinyl resin particles, for example, propane, butane, isobutane, pentane, isopentane, cyclopentane, hexane, mixtures thereof, and the like. Hydrofluorocarbons such as a hydrocarbon compound, a hydrofluorocarbon (HCFC), a hydrofluorocarbon (HFC), a mixture thereof, and the like, may be used alone or in combination of two or more thereof. The content of the blowing agent may be 5 to 15 parts by weight, for example, 7 to 11 parts by weight, based on 100 parts by weight of the aromatic vinyl monomer. Within the above range, the foamability of the expandable aromatic vinyl resin particles may be excellent.

In embodiments, the expandable aromatic vinyl-based resin particles may have an average particle diameter of 0.35 to 2.0 mm, for example 0.5 to 1.2 mm, measured using a sieve of ASTM E-11 standard. In the above range, it is possible to minimize the voids generated during particle molding, it may be excellent in flame retardancy and thermal conductivity.

In embodiments, the expandable aromatic vinyl-based resin particles may be 60 to 95% by weight, for example 80 to 95% by weight of the particles having a particle diameter of 0.5 to 1.2 mm in 100% by weight of the total particles. In the above range, it is possible to minimize the voids generated during particle molding, it may be excellent in flame retardancy and thermal conductivity.

In embodiments, the expandable aromatic vinyl-based resin particles may have a thermal conductivity of 0.031 to 0.035 W / m · K, for example 0.0320 to 0.0335 W / m · K, measured based on KS M 3808.

In an embodiment, the expandable aromatic vinyl-based resin particles may have a burning length of 40 to 55 mm, for example 45 to 55 mm, of 150 × 50 × 12 mm size specimens measured according to KS M ISO 9772. The time may be 3 to 11 seconds, for example 5 to 11 seconds.

The foamed molded article according to one embodiment of the present invention is formed by foaming the expandable aromatic vinyl-based resin particles. For example, after pre-expanding the expandable aromatic vinyl-based resin particles, the foamed aromatic vinyl-based resin particles are filled in a mold, and heated and fused. Can be formed.

In an embodiment, the foamed molded article is filled (introduced) into the non-hermetic mold of the expandable aromatic vinyl-based resin particles, for example, the expandable foam using hot air or steam at a pressure of 0.1 to 0.5 g / cm ² The foamed molded article can be produced by fusing the aromatic vinyl resin particles into the mold. The foamed molded article has a uniform cell structure and may have a cell size of 0.001 to 0.05 mm, for example, 0.005 to 0.02 mm. In the above range, the foamed molded article may have excellent foamability, adhesion, strength, buffering properties, and the like.

In an embodiment, the expandable aromatic vinyl resin particles may be pre-expanded particles prepared by pre-expanding (heating above the softening point). For example, the pre-expansion is heated to 80 to 120 ℃, for example 90 to 110 ℃ using a heating medium such as steam, such as a predetermined bulk density, for example, 10 to 35 kg / m ³ , specifically 15 to 30 kg / m ³ It may be to foam. The balance of foamability and strength can be maintained well in the above range.

The pre-expanded particles and foamed molded article can be easily prepared by those skilled in the art to which the present invention pertains.

Hereinafter, the present invention will be described in more detail with reference to examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Example

Examples 1-4 and Comparative Examples 1-3

According to the content of Table 1, (A) aromatic vinyl monomer (styrene), (B) initiator (benzoyl peroxide), (C) nucleating agent (polyethylene wax, Baker Hughes), (D) flame retardant (1) , 1 '-(isopropylidene) bis [3,5-dibromo-4- (2,3-dibromo-2-methylpropyl) benzene], Daihachi Chemical Industry Co., Ltd.) and (E) insulating material ( Graphite, Qingdao Xinghe Graphite Co., Ltd. was added and stirred to prepare a dispersion, and then (F) water (ultra pure water), (G) tricalcium phosphate and (H) potassium carbonate or (I) sodium benzoate were added to a 100 L reactor. To prepare a dispersion medium by stirring and mixing, the dispersion was mixed into a 100L reactor to prepare a suspension, the suspension was reacted at 91.5 ℃ for 5 hours, and the blowing agent (pentane mixed gas) at 121 ℃ to the aromatic vinyl monomer 100 9 parts by weight based on parts by weight, and maintained for 2 hours to prepare expandable aromatic vinyl resin particles It was. After drying the prepared expandable aromatic vinyl-based resin particles for 3 hours, it was put into a flat plate molding machine to foam at a steam pressure of 0.2 to 0.5 g / cm ² to prepare a foamed molded article. The prepared foamed molded article was dried in a drying chamber at 50 ° C. for 24 hours, and then cut to prepare a test piece for measuring physical properties. The physical properties (average particle diameter, particle distribution, thermal conductivity and flame retardance) of the test piece were measured, and the results are shown in Table 1 below.

Property measurement method

(1) Electrical conductivity (unit: μs / cm): According to ASTM D1125, it was measured by an electrical conductivity measuring instrument (METGoler TOLEDO, FiveGoTM F3 Conductivity).

(2) Average particle size (unit: mm): A sieve of ASTM E-11 standard was used, and foamable aromatic vinyl resin particles were sorted for 5 minutes with a shaker, and the average particle diameter thereof was measured.

(3) Particle distribution (unit: wt%): Using a sieve of ASTM E-11 standard, the expandable aromatic vinyl-based resin particles were sorted for 5 minutes with a shaker, and in 100 wt% of the total particles. The content (wt%) of the expandable aromatic vinyl resin particles having a particle diameter of 0.5 to 1.2 mm was measured.

(4) Thermal Conductivity (Unit: W / mK): The thermal conductivity of the foam molded body specimens was measured based on KS M 3808.

(5) Evaluation of flame retardancy: According to KS M ISO 9772, the combustion length (unit: mm) and the combustion time (unit: second) of five foamed molded specimens of size 150 × 50 × 12 mm were measured and averaged.

Example Comparative example One 2 3 4 One 2 3 Dispersoid (A) (parts by weight) 100 100 100 100 100 100 100 (B) (parts by weight) 0.45 0.45 0.45 0.6 0.45 0.45 0.45 (C) (parts by weight) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 (D) (parts by weight) 0.65 0.65 0.65 0.65 0.65 0.65 0.65 (E) (parts by weight) 4.0 4.0 4.0 4.0 - 4.0 4.0 Dispersion (F) (parts by weight) 100 100 100 100 100 100 100 (G) (parts by weight) 1.0 0.75 0.5 0.5 0.45 1.0 1.0 (H) (parts by weight) 0.1 0.1 0.1 0.1 - - - (I) (parts by weight) - - - - 0.2 - 0.2 Weight ratio (dispersion: dispersion medium) 1: 1 1: 1 1: 1 1: 1 1: 1 1: 1 1: 1 Dispersion medium electrical conductivity
(μs / cm) 3,489 3,404 3,389 3,564 1,505 3 1,583 Average particle diameter (mm) 0.56 0.57 1.11 0.76 0.92 0.22 Dispersion
Destruction Particle Distribution (wt%) 62.6 65.1 81.3 86.7 95.4 2.8 Thermal Conductivity (W / mK) 0.0331 0.0337 0.0326 0.0324 0.0401 Measure
Impossible Flame retardant (burning time, seconds) 8.0 6.1 6.6 5.3 4.8 Flame retardant (combustion length, mm) 48.4 50.4 46.2 47.0 42.4

From the above results, it can be seen that the expandable aromatic vinyl resin particles of the present invention have an average particle diameter of 0.56 to 1.11 mm, and have a homogeneous particle distribution. In addition, it can be seen that the foamed molded article formed from the expandable aromatic vinyl resin particles is excellent in both heat insulating properties and flame retardancy.

On the other hand, in Comparative Example 1 in which sodium benzoate was applied instead of potassium carbonate without applying an insulating material, the thermal conductivity was significantly reduced. It can be seen that the flame retardancy, heat insulation, and the like are deteriorated. In Comparative Example 3 in which sodium benzoate was applied instead of potassium carbonate, it was found that the particles were not dispersed and particles were not formed.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (15)

A dispersion is prepared by mixing a dispersion comprising water, tricalcium phosphate, and potassium carbonate with a dispersion comprising an aromatic vinyl monomer, an initiator, a nucleating agent, a flame retardant, and a heat insulating material;
Reacting the suspension to prepare aromatic vinyl resin particles; And
A foaming aromatic vinyl-based resin particle manufacturing method comprising the step of preparing a foamable aromatic vinyl-based resin particles by adding a blowing agent to the aromatic vinyl-based resin particles.
The method of claim 1, wherein the dispersoid comprises 100 parts by weight of an aromatic vinyl monomer, 0.3 to 1.2 parts by weight of initiator, 0.2 to 1.0 parts by weight of nucleating agent, 0.3 to 1.5 parts by weight of flame retardant, and 2.0 to 6.0 parts by weight of insulating material, The dispersion medium comprises 100 parts by weight of water, 0.2 to 1.5 parts by weight of tricalcium phosphate, and 0.04 to 0.2 parts by weight of potassium carbonate, and the weight ratio of the tricalcium phosphate and the potassium carbonate is 4: 1 to 11: 1, and the dispersion The weight ratio of the quality and the dispersion medium is 1: 0.8 to 1: 1.2, characterized in that the foamable aromatic vinyl resin particle production method.
The method of claim 1, wherein the weight ratio of the heat insulating material and the tricalcium phosphate is 1: 0.1 to 1: 0.3.
The method of claim 1, wherein the initiator is selected from the group consisting of benzoyl peroxide, dicumyl peroxide, tertiary-amyl (2-ethylhexyl) monoperoxycarbonate, and tertiary-butyl (2-ethylhexyl) monoperoxycarbonate, di A method for producing expandable aromatic vinyl resin particles comprising at least one of benzoyl peroxides.
The method of claim 1, wherein the nucleating agent is a polyolefin wax.
The flame retardant of claim 1, wherein the flame retardant is hexabromo cyclo dodecane, 1,3-butane brominated benzene ethyl polymer, 1,1 ′-(isopropylidene) bis [3,5-dibromo-4 -(2,3-dibromo-2-methylpropyl) benzene] A method for producing expandable aromatic vinyl-based resin particles, characterized in that at least one.
The method of claim 1, wherein the heat insulating material comprises at least one of graphite, carbon black, and alumina.
The method of claim 1, wherein the dispersion medium is a foamed aromatic vinyl resin particle manufacturing method, characterized in that the electrical conductivity measured in accordance with ASTM D1125, 1,700 to 10,000 μs / cm.
The method of claim 1, wherein the reaction is performed at 80 to 130 ° C.
The method according to claim 1, wherein the expandable aromatic vinyl resin particles have a mean particle size of 0.35 to 2.0 mm measured using a sieve of ASTM E-11 standard.
The method according to claim 1, wherein the expandable aromatic vinyl resin particles are particles having a particle size of 0.5 to 1.2 mm, 60 to 95% by weight based on 100% by weight of the total particles.
The method according to claim 1, wherein the expandable aromatic vinyl resin particles have a thermal conductivity of 0.031 to 0.035 W / m · K measured according to KS M 3808.
The method of claim 1, wherein the foamable aromatic vinyl-based resin particles have a burning length of 40 to 55 mm and a burning time of 3 to 11 seconds of 150 × 50 × 12 mm specimen measured according to KS M ISO 9772 A method for producing an expandable aromatic vinyl resin particle.
The expandable aromatic vinyl resin particles produced by the method for producing expandable aromatic vinyl resin particles according to any one of claims 1 to 13.
A foamed molded article characterized in that the foamable aromatic vinyl resin particles according to claim 14 are formed by preliminary foaming, filling into a mold, and heating and fusion.