KR100750626B1 - Styrene-form with excellent insulation and a manufacturing method thereof - Google Patents

Abstract

Provided is a method for preparing an extruded styrene foam having a low density, a low thermal conductivity, an excellent heat insulation and satisfactory physical properties. A method comprises the steps of injecting 0.1-5 wt% of a graphite powder, 1-5 wt% of HBCD as a bromine-based flame retardant, and 0.3-4 wt% of a nucleating agent based on the weight of a polystyrene resin into an extruder and melting them at a temperature of 180-240 deg.C; injecting 3-15 wt% of a foaming agent; and extruding the mixture at a temperature of 100-140 deg.C to prepare an extruded styrene foam. Preferably the HBCD is EPS (expanded polystyrene foam) or XPS (extruded polystyrene foam); and the nucleating agent is talc, calcium carbonate or silica.

Description

Manufacturing method of extruded styrene foam with excellent insulation {STYRENE-FORM WITH EXCELLENT INSULATION AND A MANUFACTURING METHOD THEREOF}

The present invention relates to a method for producing an extruded styrene foam having excellent thermal insulation, and more particularly, to a polystyrene resin as a main raw material, graphite powder, a flame retardant, and a nucleating agent are added to an extruder, melted, and then extruded by adding a blowing agent. It is to make this excellent extruded styrene foam.

The density of foamed polystyrene foam boards used for thermal insulation is generally about 30 g / l, since the thermal conductivity of the expanded polystyrene foam has a minimum value at this density.

The density of foamed polystyrene foam boards used for thermal insulation is generally about 30 g / l, since the thermal conductivity of the expanded polystyrene foam has a minimum value at this density.

In order to save material and space, it is preferable to use foam boards having a lower density, in particular less than 15 g / l, for thermal insulation. The production of such foams is technically free of problems.

However, the low density foam boards dramatically reduce the thermal insulation performance and do not meet the requirements of thermal conductivity class 035 (DIN 18 164, 1 part).

It is known that the thermal conductivity of the foam can be reduced by the incorporation of heatless materials such as carbon black, metal oxides, metal powders or pigments.

Thus, EP 372 343 describes polystyrene foams containing 1 to 25% by weight carbon black. The particle size of the carbon black is 10 to 100 nm.

The polystyrene foams described are mainly produced by extrusion method, preferably the density is 32-40 g / l. Also described is a process for mixing carbon black concentrate in polystyrene with a blowing agent into a polystyrene melt and extruding and crystallizing the mixture to produce particulate polystyrene containing blowing agent which is very complicated.

International Publication No. 94/13721 describes similar foams with a particle size of carbon black greater than 150 nm.

EP 620 246 describes expanded polystyrene foam moldings containing particulate heatless materials, in particular carbon black and also graphite. The density of the moldings is less than 20 g / l.

The incorporation of the particles into the molding is preferably carried out by coating the surface of the prefoamed polystyrene beads or by embedding them in a polystyrene particle body which has not yet been foamed. However, distributing the particles on the surface of the polystyrene particles greatly impairs the adhesion of the prefoamed beads, resulting in low quality foams, and the particles can also peel off from the surface of the moldings. In both cases the particles are not evenly distributed inside the polystyrene particles.

The present invention has been invented to solve the above problems, and an object thereof is to form a foamed polystyrene foam having low density and especially low thermal conductivity and to be processed to have good processing properties and good physical properties. The present invention provides an extruded styrene foam having excellent heat insulation and a method of manufacturing the same.

Characteristic technical features of the present invention for achieving the above object, 0.1-5% by weight of graphite powder relative to the weight of polystyrene resin, flame retardant is added to the extruder by broth-based HBCD 1-5% by weight, nucleating agent 0.3-4% by weight It melts at 180-240 ° C, and 3-15% by weight of blowing agent is extruded at 100-140 ° C.

In addition, the graphite powder is any one of natural graphite or synthetic graphite (artificial graphite), the HBCD is any one of expanded polystyrene foam (EPS) or extruded polystyrene foam (XPS), the nucleating agent is TALC, calcium carbonate, Any one of silica, and the blowing agent is any one of H ₂ O, alcohol, HCFCs (HCFC-22, HCFC-142b), butane, CO ₂ , DME (CH ₃ OCH ₃ ) that has been liquefied by pressing.

Referring to the method of producing an extruded styrene foam with excellent thermal insulation of the present invention having the above characteristics as follows.

First, the reasons for the content of each component used to prepare the extruded styrene foam having excellent thermal insulation of the present invention will be described.

Polystyrene resin (polymer) was used as the main material for use in extrusion applications with a weight molecular weight of 20-300,000. Styrofoam polystyrene polymer recycled according to extrusion conditions can be used at 0.1-50% of the main material, so that process unstable due to poor thermal insulation or uneven quality due to open cell formation can be avoided.

The graphite powder may be either natural graphite or synthetic graphite (artificial graphite). The reason for the amount of the graphite powder used is 0.1-5% by weight. When used, the amount of graphite used was 0.1-5% by weight because it affects the cell structure including opening the cell, thereby increasing the thermal conductivity rather than decreasing the thermal conductivity.

In addition, the graphite has a density of 20-40 g / l, which is difficult to maintain the product shape at a low density below 20 g / l, and is uneconomical due to a high manufacturing cost at a high density above 40 g / l.

The synthetic graphite, that is, artificial graphite, is a graphitization process that changes the structure of the clove array when the coke extracted from petroleum coke or the coke extracted from coal is heated at 2,500 ° C. or more. It is called graphite (synthetic graphite).

The flame retardant is bromine-based, and the reason for using the bromine-based foam is that the expanded polystyrene foam board is made of bromine so that it is self-extinguishing by flame retardant mechanisms such as incombustible gas generation and digestion. The flame retardant is used in the form of powder or in the form of mixed (master batch) pellets with polystyrene resin before use, and its amount is 1-5% by weight, because less than 1% by weight can meet the KS M 3808 combustibility standards. If it is more than 5% by weight, it is uneconomical with the use of expensive flame retardant, and 1-5% by weight is used because it lowers product strength and thermal conductivity.

The flame retardant used as described above is bromine-based HBCD, the HBCD is Hexabromocyclododecane is an organic halogen-based flame retardant material used in polystyrene-based EPS (expanded polystyrene foam) or XPS (extruded polystyrene foam).

The nucleating agent is used to supplement the thermal insulation during the manufacture of the extruded expandable polystyrene polymer and at the same time, it is used to make the expanded cell size small or uniform. The amount of the nucleating agent is preferably 0.3-4.0%.

The blowing agent is used to induce sufficient foaming of the polystyrene resin. The amount of the blowing agent is 3-15% by weight because the polystyrene resin cannot be sufficiently foamed below 3% by weight, thereby increasing the density of the product. Exceeding the weight% causes blowing agent loss, making it difficult to obtain an uneconomical and flat plate. Therefore, it is preferable to use 3-15% by weight of the blowing agent.

The blowing agent is any one of H ₂ O, alcohol, HCFCs (HCFC-22, HCFC-142b), butane, CO _{2, and} DME (CH ₃ OCH ₃ ) which have been liquefied under pressure. 22 (Monochloro difluoro methane), HCFC-142b (Monochloro difluoro ethane).

Hereinafter, an embodiment of the present invention will be described in detail.

Example 1

100 kg of polystyrene resin (LG Chemistry 24HRE) was added as an additive to flame retardant 3 kg, 1 kg of nucleating agent was mixed and dissolved at 220 ° C., and 8 kg of blowing agent HCFC22,142b was added to 120 ° C. to produce a cold extrusion expanded polystyrene polymer. The density was 30 g / l. Thermal conductivity test method KS L 9016 at the average temperature of 20 ± 5 ℃, the thermal conductivity was 0.0253W / mk. And 0.0235 W / mk was obtained when 0.3% of graphite particles were added.

Example 2

When the graphite particles were added 0.9% under the same conditions as in the above example, 0.0218w / mk was obtained.

Example 3

0.0225w / mk was obtained when 0.9% was added repeatedly under the same conditions in the above examples.

Example 4

100 kg of polystyrene resin (LG Chemistry 24HRE) was added as an additive to flame retardant 3 kg and nucleating agent 2 kg, and the mixture was dissolved at 220 ° C., and 9 kg of blowing agent HCFC22,142b was added to 120 ° C. to produce a cold-extruded polystyrene polymer. The density was 30 g / l. The thermal conductivity was 0.0236 W / mk. And 0.0212 W / mk was obtained when 0.9% of graphite particles were added.

Example 5

100 kg of polystyrene resin (LG Chemistry 24HRE) was added as an additive to flame retardant 3 kg and 1 kg of nucleating agent, and the mixture was dissolved in 220 ° C., and 8 kg of blowing agent HCFC22,142b was added to 120 ° C. to produce a cold-extruded polystyrene polymer. The density was 30 g / l. The thermal conductivity was 0.0241 W / mk. And when 2.4% of graphite particles were added, 0.0204 W / mk was obtained.

The present invention as described above is 0.1-5% by weight graphite powder relative to the weight of the polystyrene resin, flame retardant is bromine-based, 1-5% by weight of HBCD, 0.3-4% by weight of the nucleating agent is melted at 180-240 ℃, 3-15% by weight of the blowing agent is extruded at 100-140 ° C. to form a polystyrene foam having a low density and low thermal conductivity, thereby providing an extruded styrene foam manufacturing method having excellent heat insulating properties having good processing properties and good physical properties. It can work.

Claims (6)

0.1-5% by weight of graphite powder relative to the weight of polystyrene resin, flame retardant is bromine-based, 1-5% by weight of HBCD and 0.3-4% by weight of nucleating agent are melted at 180-240 ° C, and 3-15% by weight of blowing agent Extruded styrene foam manufacturing method, characterized in that the extruded at 100-140 ℃ by adding a. The method of claim 1, wherein the graphite powder is any one of natural graphite or synthetic graphite (artificial graphite). The method of claim 1, wherein the HBCD is either expanded polystyrene foam (EPS) or extruded polystyrene foam (XPS). The method of claim 1, wherein the nucleating agent is any one of TALC, calcium carbonate, silica. The method of claim 1, wherein the blowing agent is any one of H ₂ O, alcohol, HCFCs (HCFC-22, HCFC-142b), butane, CO _2, DME (CH ₃ OCH ₃ ) that is liquefied by pressing Method for producing extruded styrene foam having excellent thermal insulation. delete