KR102594257B1 - Manufacturing method of porous polyurethane foam having excellent flame retardancy - Google Patents

Abstract

The present invention is a porous polyurethane foam formed by the polymerization reaction of isocyanate and polyol, and one or more inorganic particles selected from the group consisting of oxides, hydroxides, and phosphorylates are dispersed in the cell walls surrounding the pores in the porous polyurethane foam. It relates to porous polyurethane foam and its manufacturing method. According to the present invention, it is possible to manufacture porous polyurethane foam that has the excellent insulation properties of polyurethane foam and has enhanced stability against fire.

Description

{Manufacturing method of porous polyurethane foam having excellent flame retardancy}

The present invention relates to polyurethane foam and a method of manufacturing the same, and more specifically, to a porous polyurethane foam with excellent thermal insulation properties and enhanced stability against fire, and a method of manufacturing the same.

Polyurethane is not a thermosetting resin, but is a plastic with a similar three-dimensional structure. Polyurethane has strong chemical resistance and electrical insulation properties, so it is used in insulation materials. It is also used as a substitute for rubber due to its good elasticity.

Polyurethane foam is economically inexpensive, easy to handle, and has excellent insulation performance, so it is used for various purposes such as building insulation and automobile insulation. When a fire occurs, these polyurethane foams or materials mainly produce carbon monoxide, nitrogen oxides, and hydrogen cyanide.

Due to this flammability, if a fire occurs, it can cause serious casualties or huge property damage. Since polyurethane insulation is light, easy to process, and economically inexpensive, it is widely used as an insulation material for buildings or automobiles. However, due to these problems, the use of polyurethane insulation is gradually becoming difficult to apply. Therefore, in order to solve this problem, research is being conducted to make it difficult to ignite by coating polyurethane insulation or adding iodine. In addition, due to the flammability of polyurethane, methods of treating it as nonflammable or adding additives that can provide nonflammability properties are being studied.

Republic of Korea Registered Utility Model Publication No. 20-0252362

The problem to be solved by the present invention is to reduce the emission of toxic gases caused by fire or suppress the occurrence of fire by dispersing at least one type of inorganic particles selected from the group consisting of oxides, hydroxides, and phosphorylates inside the polyurethane foam. The aim is to provide a flame-retardant porous polyurethane foam that has the excellent insulation properties of polyurethane foam while enhancing fire stability, and a method of manufacturing the same.

The present invention is a porous polyurethane foam formed by the polymerization reaction of isocyanate and polyol, and one or more inorganic particles selected from the group consisting of oxides, hydroxides, and phosphorylates are dispersed in the cell walls surrounding the pores in the porous polyurethane foam. Provides a porous polyurethane foam characterized in that it is.

The oxide may include fumed silica with a hydrophilic surface.

The oxide may include fumed silica with a hydrophobic surface.

The hydroxide may include one or more materials selected from the group consisting of aluminum hydroxide and magnesium hydroxide.

The phosphorylate may include one or more substances selected from the group consisting of aluminum phosphate and ammonium phosphate.

The inorganic particles may include particles larger than 10 nm and smaller than 100 μm.

In addition, the present invention includes the steps of (a) forming an isocyanate solution, (b) forming a polyol solution, and (c) mixing the isocyanate solution and the polyol solution and polymerizing the isocyanate and the polyol to form a porous poly. Comprising the step of forming a urethane foam, wherein at least one inorganic particle selected from the group consisting of oxide, hydroxide, and phosphorus is dispersed in at least one of the isocyanate solution and the polyol solution, and within the porous polyurethane foam. A method for producing porous polyurethane foam is provided, wherein one or more types of inorganic particles selected from the group consisting of oxides, hydroxides, and phosphorylates are dispersed in the cell walls surrounding the pores.

The oxide may include fumed silica with a hydrophilic surface.

The oxide may include fumed silica with a hydrophobic surface.

The hydroxide may include one or more materials selected from the group consisting of aluminum hydroxide and magnesium hydroxide.

The phosphorylate may include one or more substances selected from the group consisting of aluminum phosphate and ammonium phosphate.

The inorganic particles may include particles larger than 10 nm and smaller than 100 μm.

The isocyanate solution is selected from the group consisting of methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). It may contain more than one type of substance.

The polyol solution contains at least one material selected from the group consisting of diethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyester, polyether, and polytetramethylene ether glycol (PTMEG; Polytetramethylene Ether Glycol). can do.

In step (c), at least one amine compound selected from the group consisting of triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, and 1,4-diazabicyclooctane (DABCO) is added to the isocyanate solution and the polyol solution. The polymerization reaction can be achieved by mixing together.

In step (c), a metal compound containing at least one material selected from the group consisting of an alkyl tin carboxyl group, an alkyl zinc carboxyl group, an alkyl bismuth carboxyl group, and a mercapto group is mixed with the isocyanate solution and the polyol solution. A polymerization reaction can occur.

In step (c), CO ₂ gas, water (H ₂ O), CFC11 (Trichlorofluoromethane), HFC (pentafluoropropane), CHFC (1,1 Dichloro-1-fluoroethane), cyclopentane, methyl formate ( The polymerization reaction is carried out by mixing one or more materials selected from the group consisting of methyleformate), HFC-245fa (1,1,1,3,3-Pentafluoropropane), and HFO (Hydrofluoroolefin) with the isocyanate solution and the polyol solution. It can be done.

According to the present invention, by introducing inorganic particles such as oxides, hydrates, and phosphorylates into polyurethane foam, the cell size within the polyurethane foam is reduced, thereby improving thermal conductivity. The size of pores formed within polyurethane foam ranges from hundreds of micrometers to millimeters in size. When inorganic particles enter, the inorganic particles absorb the vaporized gas and act as a nucleating agent for the pores. As a result, the pore size tends to decrease. As a result, the size of the pores becomes smaller, which leads to a decrease in thermal conductivity. Since the smaller pore size acts as a factor that hinders heat transfer by convection, this can lower the thermal conductivity and improve the insulation effect. In addition, in order for water molecules chemically bonded with hydroxide to decompose, heat must be absorbed, and since inorganic particles do not decompose by heat, they act to prevent polyurethane foam from burning. In the case of phosphorylate, the phosphorylate decomposes and plays a role in carbonizing polyurethane, and the carbide produced at this time acts to hinder the combustion of polyurethane. In addition, the amount of polyurethane burned per unit mass decreases depending on the content of inorganic particles, resulting in a decrease in the amount of heat generated per unit mass, resulting in a flame retardant effect of polyurethane foam.

The inorganic particles are dispersed in the cell walls surrounding the pores, which has the effect of lowering the fire risk of polyurethane foam.

1 is a diagram showing the structure of polyurethane foam according to a preferred embodiment of the present invention.
Figure 2 is a scanning electron microscope (SEM) photograph and an energy dispersive
Figure 3 is a scanning electron microscope (SEM) photo EDX (energy dispersive
Figure 4 is a scanning electron microscope (SEM) photo EDX (energy dispersive
Figure 5 is a differential thermal analysis and thermogravimetric analysis graph of polyurethane foam manufactured by adding aluminum phosphate according to Example 4.
Figure 6 is a differential thermal analysis and thermogravimetric analysis graph of polyurethane foam prepared by adding ammonium phosphate according to Example 5.
Figure 7 is a differential thermal analysis and thermogravimetric analysis graph of polyurethane foam prepared by adding ammonium phosphate and aluminum hydroxide according to Example 6.
Figure 8 is a differential thermal analysis and thermogravimetric analysis graph of polyurethane foam prepared by adding magnesium hydroxide and ammonium phosphate according to Example 7.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings. However, the following examples are provided to enable those skilled in the art to fully understand the present invention, and may be modified into various other forms, and the scope of the present invention is limited to the examples described below. It doesn't work.

When it is said that one component "includes" another component in the detailed description or claims of the invention, this shall not be construed as being limited to consisting of only that component, unless specifically stated to the contrary, and other components may not be added. It must be understood that it can be included.

The porous polyurethane foam according to a preferred embodiment of the present invention is a porous polyurethane foam formed by the polymerization reaction of isocyanate and polyol, and the cell walls surrounding the pores in the porous polyurethane foam are composed of oxides, hydroxides, and phosphorylates. One or more types of inorganic particles selected from the group are dispersed.

The oxide may include fumed silica with a hydrophilic surface.

The oxide may include fumed silica with a hydrophobic surface.

The hydroxide may include one or more materials selected from the group consisting of aluminum hydroxide and magnesium hydroxide.

The phosphorylate may include one or more substances selected from the group consisting of aluminum phosphate and ammonium phosphate.

The inorganic particles may include particles larger than 10 nm and smaller than 100 μm.

A method for producing porous polyurethane foam according to a preferred embodiment of the present invention includes (a) forming an isocyanate solution, (b) forming a polyol solution, and (c) mixing the isocyanate solution and the polyol solution. And polymerizing the isocyanate and the polyol to form a porous polyurethane foam, wherein at least one of the isocyanate solution and the polyol solution contains one or more inorganic particles selected from the group consisting of oxides, hydroxides, and phosphorylates. is dispersed, and one or more types of inorganic particles selected from the group consisting of the oxide, hydroxide, and phosphorus are dispersed in the cell walls surrounding the pores in the porous polyurethane foam.

The oxide may include fumed silica with a hydrophilic surface.

The oxide may include fumed silica with a hydrophobic surface.

The hydroxide may include one or more materials selected from the group consisting of aluminum hydroxide and magnesium hydroxide.

The phosphorylate may include one or more substances selected from the group consisting of aluminum phosphate and ammonium phosphate.

The inorganic particles may include particles larger than 10 nm and smaller than 100 μm.

The isocyanate solution is selected from the group consisting of methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). It may contain more than one type of substance.

The polyol solution contains at least one material selected from the group consisting of diethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyester, polyether, and polytetramethylene ether glycol (PTMEG; Polytetramethylene Ether Glycol). can do.

In step (c), at least one amine compound selected from the group consisting of triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, and 1,4-diazabicyclooctane (DABCO) is added to the isocyanate solution and the polyol solution. The polymerization reaction can be achieved by mixing together.

In step (c), a metal compound containing at least one material selected from the group consisting of an alkyl tin carboxyl group, an alkyl zinc carboxyl group, an alkyl bismuth carboxyl group, and a mercapto group is mixed with the isocyanate solution and the polyol solution. A polymerization reaction can occur.

In step (c), CO ₂ gas, water (H ₂ O), CFC11 (Trichlorofluoromethane), HFC (pentafluoropropane), CHFC (1,1 Dichloro-1-fluoroethane), cyclopentane, methyl formate ( The polymerization reaction is carried out by mixing one or more materials selected from the group consisting of methyleformate), HFC-245fa (1,1,1,3,3-Pentafluoropropane), and HFO (Hydrofluoroolefin) with the isocyanate solution and the polyol solution. It can be done.

Below, the porous polyurethane foam according to a preferred embodiment of the present invention will be described in more detail.

Figure 1 is a diagram showing the structure of porous polyurethane foam according to a preferred embodiment of the present invention.

Referring to Figure 1, the porous polyurethane foam according to a preferred embodiment of the present invention is a polyurethane foam formed by the polymerization reaction of isocyanate and polyol, and has a cell wall surrounding the pores 10 in the porous polyurethane foam ( Inorganic particles 30 are dispersed in 20). The inorganic particles may be one or more types of particles selected from the group consisting of oxides, hydroxides, and phosphorylates.

The polyurethane foam according to a preferred embodiment of the present invention is porous, and the cell walls 20 surround the pores 10.

Inorganic particles 30 are dispersed in the cell wall 20 surrounding the pores 10. The inorganic particles are preferably composed of particles having a size between 10 nm and 100 ㎛, and may be hydroxide particles, phosphorite particles, oxide particles, or a mixture thereof that can undergo an endothermic reaction in the event of fire.

When the inorganic particles 30 are particles smaller than 10 nm, the apparent density is very low, for example, about 0.1 g/cc, so the volume to mass ratio is large, so it is very difficult to disperse the inorganic nanoparticles in the polyurethane foam. Additionally, in the case of particles larger than 100㎛, it is very difficult to disperse them in an isocyanate solution or polyol solution, which are raw materials for polyurethane foam. Therefore, the inorganic particles need to have a size or surface shape that allows them to be well dispersed in an isocyanate or polyol solution, which is a polyurethane raw material solution. In the case of the oxide particle, it may be an oxide particle whose surface is modified to be hydrophilic, or it may be an oxide particle whose surface is modified to be hydrophobic. An example of the oxide particle is fumed silica, which is either fumed silica whose surface is treated with silane and thus has a hydrophobic surface, or which is not treated with silane and whose surface is a hydroxyl group and thus hydrophilic. It could be fumed silica. In the case of inorganic particles with hydrophilic properties, they disperse well in polyol solutions and also disperse well in isocyanate. However, since hydrophobic particles are better dispersed in isocyanate than polyol, it can be determined whether the inorganic particles are dispersed in isocyanate or polyol depending on the surface shape of the particles and whether they are hydrophilic or hydrophobic.

The inorganic particles 30 may be particles of hydroxide (hydroxide compound) such as aluminum hydroxide or magnesium hydroxide. In the case of hydroxide, an endothermic reaction is required to decompose the bound water molecules. Therefore, if a fire occurs, it can have the effect of delaying the fire depending on the heat absorbed by the hydroxide contained in the polyurethane foam. In the case of hydroxide, it is preferable to disperse it in a polyol solution and then react it with isocyanate.

The inorganic particles 30 may be phosphoric acid (phosphoric acid compound) such as ammonium phosphate or aluminum phosphate. In the case of phosphorus compounds such as ammonium phosphate or aluminum phosphate, they have the effect of delaying a fire by carbonizing the surface when decomposing polyurethane foam.

Hereinafter, the method for manufacturing porous polyurethane foam according to a preferred embodiment of the present invention will be described in more detail.

An isocyanate solution is formed. The isocyanate solution is selected from the group consisting of methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). It may contain more than one type of substance.

A polyol solution is formed. The polyol solution contains at least one material selected from the group consisting of diethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyester, polyether, and polytetramethylene ether glycol (PTMEG; Polytetramethylene Ether Glycol). can do. In the case of the polyol solution, those with two hydroxyl groups are called glycols or diols, diethylene glycol and polyethylene glycol are etherified ethylene glycol, and dipropylene glycol and polypropylene glycol are etherified propylene glycol. .

Inorganic particles are dispersed in at least one of the isocyanate solution and the polyol solution. The inorganic particles may be one or more types of particles selected from the group consisting of oxides, hydroxides, and phosphorylates. Isocyanate solutions or polyol solutions make it easy to disperse hydrophilic particles. However, when a dispersant such as silane or a surfactant is used in an isocyanate solution or polyol solution, hydrophobic particles can also be dispersed.

In order to disperse inorganic particles (nanopore inorganic material) on the cell walls of the polyurethane foam, the inorganic particles are dispersed in a solution containing isocyanate or a polyol solution containing polyol. The surface of the inorganic particle may be modified to be hydrophilic or hydrophobic. If the inorganic particle is an oxide particle, the surface may be hydrophilic in the form of a hydroxyl group (OH), or may be treated with a silane compound and the surface may be substituted with an alkyl group to make it hydrophobic.

The amount of dispersion may vary depending on the particle size, pore size, specific surface area, etc. of the inorganic particles, but it is preferable to disperse the inorganic particles at a weight ratio of about 0.1 to 50% compared to the isocyanate solution or polyol solution. If the inorganic particles are dispersed in excess of 50%, the viscosity of the solution may increase, which may cause problems such as not being uniformly dispersed or the polyurethane reaction due to mixing of the isocyanate solution and the polyol solution not occurring uniformly. Therefore, it is desirable to maintain the content ratio of inorganic particles within 50%.

The inorganic particles preferably have a particle size of 10 nm to 100 micrometers or less. If the size is less than 10nm, it is difficult to disperse it in the raw materials that make up polyurethane foam, so particles smaller than this are not desirable. In addition, if the particle size is larger than 100 micrometers, it may be difficult to disperse in an isocyanate solution or polyol solution, which is a polyurethane raw material, and ultimately precipitation occurs in the solution, which may have the disadvantage of making uniform dispersion difficult.

The inorganic particles may be oxide particles such as fumed silica. In the case of hydrophobic fumed silica, the surface is modified with silane and thus has hydrophobicity, and it is possible to disperse it in an isocyanate solution or polyol solution. The fumed silica may be an inorganic particle whose surface is modified to be hydrophilic. Hydrophilic inorganic particles can also be dispersed. For example, general fumed silica has hydrophilic properties, and it is also possible to disperse it.

The inorganic particles may be hydroxide particles such as aluminum hydroxide or magnesium hydroxide. In the case of hydroxide (hydroxide compound), an endothermic reaction is necessary to decompose the bound water molecules. Therefore, if a fire occurs, it can have the effect of delaying the fire depending on the heat absorbed by the hydroxide contained in polyurethane. In the case of such hydroxides, it is preferable to disperse them in a polyol solution and then react them with isocyanate.

The inorganic particles may be phosphate particles such as ammonium phosphate or aluminum phosphate. In the case of phosphorus compounds such as ammonium phosphate or aluminum phosphate, when decomposing polyurethane foam, it carbonizes the surface and has the effect of delaying a fire.

Additionally, the inorganic particles may be particles in the form of two or more complexes of oxides, hydroxides, and phosphorylates.

When adding the inorganic particles, for example, it may not be easy to disperse the hydrophobic inorganic particles in the polyol solution. To disperse inorganic particles, a surfactant may be added to ensure good dispersion by attaching the lipophilic group of the surfactant to one end of the hydrophobic inorganic particle and the hydrophilic group to the other end. A representative surfactant is sodium dodecyl sulfate (SDS). In addition, cationic surfactants such as cetrimonium promide (CTAB), phosphalipid-based surfactants, fatty alcohol ethoxylate-based surfactants such as octaethylene glycol monododecyl ether, and alkylphenols such as Triton X-100. Ethoxylate-based surfactant, glycerol fatty acid ether-based surfactant, Span-based surfactant, Tween-based surfactant, methyltrimethoxysilane, ethyltrimethoxysilane, methyltrichlorosilane, glycidoxytriethoxysilane. Silane-based surfactants such as can also be used. When a surfactant is added, it has the advantage of stabilizing the size of the pores formed within the polyurethane foam, that is, the cell structure, and preventing the collapse of the foam and surface voids.

The isocyanate solution and the polyol solution are mixed and the isocyanate and polyol are polymerized to form porous polyurethane foam.

When mixing the isocyanate solution and the polyol solution, at least one amine compound (amine-based) selected from the group consisting of triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, and 1,4-diazabicyclooctane (DABCO) The polymerization reaction may be achieved by mixing a catalyst) with the isocyanate solution and the polyol solution, or the amine compound may be mixed in advance with the isocyanate solution or the polyol solution and then mixed with the isocyanate solution and the polyol solution. there is. The amine compound is preferably mixed at a weight ratio of less than 5% compared to the isocyanate solution or the polyol solution.

When mixing the isocyanate solution and the polyol solution, a metal compound (metal complex catalyst) containing at least one material selected from the group consisting of an alkyl tin carboxyl group, an alkyl zinc carboxyl group, an alkyl bismuth carboxyl group, and a mercapto group is added to the isocyanate solution. The polymerization reaction can be achieved by mixing with the polyol solution, or the metal compound can be mixed in advance with the isocyanate solution or the polyol solution and then mixed with the isocyanate solution and the polyol solution. The metal compound is preferably mixed at a weight ratio of less than 5% compared to the isocyanate solution or the polyol solution.

A catalyst may be needed to cause a polyurethane reaction between the isocyanate solution and the polyol solution, and the catalyst can be classified into an amine compound (amine-based catalyst) or a metal compound (metal complex). Amine-based catalysts include triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, and tertiary amines such as 1,4-diazabicyclooctane (DABCO). The tertiary amine catalyst is selected depending on the reaction between polyol and isocyanate, gel reaction element, blowing reaction element, isocyanate trimerization reaction element, etc. Carboxyl group metal compounds containing components such as mercury, lead, tin, bismuth, and zinc are used as polyurethane catalysts. For example, there are metal compounds such as dibutyltin dilaurate or bismuth octanoate. If water is present in the reaction mixture, it is usually intentionally added as a blowing agent to form foam, and it reacts with isocyanate to form urea bonds and generate carbon dioxide, resulting in a polymer composed of urethane and urea combined. . This reaction is referred to as a blowing reaction and is catalyzed by a tertiary amine such as bis-(2-dimethylaminoethyl)ether. Since the mercury complex used in the elastomer film is toxic, it is preferable to use a metal compound containing an alkyl bismuth carboxyl group, an alkyl zinc carboxyl group, or an alkyl tin carboxyl group. Isocyanate trimer reaction is important to form an insulating hard foam, and potassium octoate may be used as a catalyst for this.

When mixing the isocyanate solution and the polyol solution, CO ₂ gas, water (H ₂ O), CFC11 (Trichlorofluoromethane), HFC (pentafluoropropane), CHFC (1,1 Dichloro-1-fluoroethane), and cyclopentane , methyleformate, HFC-245fa (1,1,1,3,3-Pentafluoropropane), and HFO (Hydrofluoroolefin). At least one material (blowing agent) selected from the group consisting of the isocyanate solution and the polyol solution The polymerization reaction can be achieved by mixing with the isocyanate solution or the polyol solution, and the isocyanate solution and the polyol solution can be mixed in advance. It is preferable to mix the material (blowing agent) at a weight ratio of less than 10% compared to the isocyanate solution or the polyol solution.

The isocyanate solution and the polyol solution can be mixed with an amine catalyst such as triethylenediamine or a metal compound catalyst such as an alkyl tin carboxyl group (metal complex catalyst), CO ₂ gas, water, CFC11, HFC, Blowing agents such as CHFC and Cyclopentane can also be mixed together. A dispersant may be mixed with the isocyanate solution and the polyol solution. The desirable properties of polyurethane are to make it porous in the form of a foam, and for this to happen, gas must be generated during polyurethane polymerization (gelation). This gas is formed by CO ₂ generated by the reaction of isocyanate and water, or by liquid volatilized above the boiling point due to the heat of reaction. This liquid contains hydrocarbon compounds such as CFC11 (Trichlorofluoromethane), HFC-245fa (1,1,13,3-pentafluoropropane), HFC-134a (1,1,12-tetrafluoropropane), HFO (Hydrofluoroolefin), and n-pentane. There is.

A catalyst, a blowing agent, etc. are mixed with the isocyanate solution and the polyol solution and mixed mechanically and uniformly. The mixing is preferably performed by rotating at 100 to 8000 rpm, preferably 2000 to 5000 rpm, using a blade or the like to ensure uniform mixing. As isocyanate and polyol polymerize, an exothermic reaction occurs, gas is generated as the blowing agent evaporates, and bubbles are uniformly dispersed to form polyurethane foam containing inorganic particles.

The polyurethane foam produced in this way is a porous polyurethane foam formed by the polymerization reaction of isocyanate and polyol, and inorganic particles are dispersed in the cell walls surrounding the pores in the porous polyurethane foam.

Below, embodiments according to the present invention are presented in detail, but the present invention is not limited to the embodiments presented below.

<Example 1>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

Fumed silica (inorganic particles) with a hydrophilic surface were added and dispersed within 50% by weight in the polyol solution. More specifically, the inorganic particles (hydrophilic fumed silica) were dispersed to achieve a weight ratio of 2.9, 5.7, 8.6, and 11.5%, respectively, compared to the polyol solution.

The isocyanate solution and the polyol solution in which inorganic particles are dispersed are mixed to form polyurethane foam in which inorganic particles are dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 1 below.

<Example 2>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

Fumed silica (inorganic particles) with a hydrophobic surface was added within 50% of the weight in the polyol solution. More specifically, the inorganic particles (hydrophobic fumed silica) were dispersed to achieve a weight ratio of 2.9, 5.7, 8.6, and 11.5%, respectively, compared to the polyol solution.

The isocyanate solution and the polyol solution in which inorganic particles were dispersed were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 1 below.

<Example 3>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution.

Aluminum hydroxide (Al(OH) ₃ ) was added within 50% by weight in the polyol solution. More specifically, aluminum hydroxide (inorganic particles) was dispersed to achieve a weight ratio of 1.4, 2.8, 4.2, and 5.6%, respectively, compared to the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

The isocyanate solution in which inorganic particles were dispersed and the polyol solution were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 2 below.

<Example 4>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution. Aluminum phosphate (AP) was added within 50% of the polyol solution. More specifically, aluminum phosphate (inorganic particles) was dispersed to achieve a weight ratio of 0.7, 1.4, 2.8, 4.0, 5.5, and 6.6%, respectively, compared to the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

The isocyanate solution in which inorganic particles were dispersed and the polyol solution were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 3 below.

<Example 5>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution. Ammonium phosphate (APP) was added within 50% of the polyol solution. More specifically, ammonium phosphate (inorganic particles) was dispersed in weight ratios of 0.7, 1.4, 2.8, 4.0, 5.5, and 6.6%, respectively, compared to the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

The isocyanate solution in which inorganic particles were dispersed and the polyol solution were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 4 below.

<Example 6>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution. Aluminum hydroxide (Al(OH) ₃ ) and ammonium phosphate (APP) were added within 50% of the polyol solution. More specifically, aluminum hydroxide and ammonium phosphate were each dispersed in a weight ratio of 4.0% compared to the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

The isocyanate solution in which inorganic particles were dispersed and the polyol solution were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 5 below.

<Example 7>

As the isocyanate solution, a mixture of methylenediphenyldiisocyanate (MDI) and toluene diisocyanate (TDI) in a volume ratio of 50:50 was used.

Polyethylene glycol was used as the polyol solution. Magnesium hydroxide (Mg(OH) ₂ ) and ammonium phosphate (APP) were added within 50% of the polyol solution. More specifically, aluminum hydroxide was dispersed at a weight ratio of 2% and ammonium phosphate at 4.0% compared to the polyol solution.

In the polyol solution, an amine compound was added within 5%, water was added within 5%, and HFC-245fa (1,1,13,3-pentafluoropropane) as a blowing agent was added within 10%.

The isocyanate solution in which inorganic particles were dispersed and the polyol solution were mixed to form polyurethane foam in which inorganic particles were dispersed. The physical properties of the polyurethane foam prepared in this way are shown in Table 6 below.

[Method of measuring physical properties]

1. Density (ρ)( ) was calculated as the apparent density after measuring the volume (V) and mass (m). The density measurement results are shown in Tables 1 to 6.

2. Thermal conductivity was measured using the normal calorimetry method. The temperature of the lower plate was kept constant at 35°C and the temperature of the upper plate was kept constant at 25°C, then the heat quantity was measured, and the thermal conductivity was calculated through the thickness and area of the sample. , where Q is the amount of heat (W/㎡), k is the thermal conductivity (W/m*?*K), and dT/dx means the temperature gradient according to the thickness of the sample.

3. Volume expansion (VE) was calculated by calculating the volume of the polyurethane foam composite (V _c ) in which nanoporous inorganic particles were dispersed compared to the volume of polyurethane (V _pu ) from the density, and then calculating the relative volume ratio as a percentage.

4. The calorific value per unit mass represents the area of the exothermic peak obtained through Differential Theramla Analysis and Thermogravimetric Analysis, converted to the calorific value per unit mass of the sample. In addition, the amount of residual inorganic matter after combustion of the sample indicates the remaining mass through thermogravimetric analysis, and the heat resistance temperature at 50% mass reduction (T50) indicates the temperature at 50% mass reduction in thermogravimetric analysis.

The physical property measurement results of the polyurethane foam manufactured according to Examples 1 to 7 are shown in Tables 1 to 6 below.

Sample No. Contents of Al(OH) ₃
(per Polyol, %) Contents of SiO ₂
(per total, %) Density
(g/ ^cm3 ) Hydrophobic One 2.9 1.4 0.0252 2 5.7 2.7 0.0224 3 8.6 4.1 0.0225 4 11.5 5.3 0.0212 Hydrophilic One 2.9 1.4 0.0243 2 5.7 2.7 0.0222 3 8.6 4.1 0.0217 4 11.5 5.3 0.0210

Table 1 shows that compared to the polyol solution according to Examples 1 and 2, hydrophilic fumed silica (Hydrophilic, K-200; brand name) and hydrophobic fumed silica (Hydrophobic, KD-15: brand name) were 2.9, 5.7, 8.6, and 11.5, respectively. It shows the physical properties of polyurethane foam manufactured by adding % weight ratio (relative to polyol). As the content of fumed silica increased, density tended to decrease.

Contents (%) Thermal conductivity (mW/mK) Density (g/cm ³ ) One 2 average One 2 average 1.4 19.74 19.93 19.83 0.026 0.027 0.0265 2.8 21.84 19.89 20.87 0.021 0.024 0.0225 4.2 20.76 20.99 20.88 0.023 0.021 0.0220 5.6 20.29 20.98 20.64 0.022 0.023 0.0225

Table 2 shows the physical properties of polyurethane foam prepared by adding aluminum hydroxide to the polyol solution at a weight ratio of 1.4, 2.8, 4.2, and 5.6% (relative to polyurethane) according to Example 3. As the content of aluminum hydroxide increases, the density slightly decreases, and the thermal conductivity tends to increase.

Sample No. Contents of AP (per total, %) Density
(g/㎤) Height(%) Mresidue Heat 95% confidence level cm % J/g PU AP 0.0 0.0353 29.5 0.68 3,800 One 0.7 0.0300 32.2 - 3,806 2 1.5 0.0340 32.4 2.28 4,277 3 2.8 0.0311 30.8 1.15 4,093 4 4.0 0.0400 29.5 1.16 4,125 5 5.5 0.0366 30.0 5.14 3,727 6 6.6 0.0387 31.0 6.54 3,261

In Table 3 above, 'AP' refers to aluminum phosphate. In Table 3, 'PU' refers to polyurethane foam manufactured without adding inorganic particles (aluminum phosphate).

Table 3 shows the physical properties of polyurethane foam prepared by adding aluminum phosphate to a weight ratio of 0.7, 1.4, 2.7, 4.0, 5.5, and 6.6% compared to the polyol solution according to Example 4. It can be seen that as the content of aluminum phosphate increases, the density increases, and the amount of inorganic substances remaining during thermal analysis also increases. Additionally, the amount of heat generated tends to decrease with the addition of minerals.

Sample No. Contents of AG (per total, %) Density
(g/㎤) Height(%) Mresidue Heat 95% confidence level cm % J/g PU APP 0.0 0.0353 29.5 0.682 3,800 One 1.4 0.0252 31.9 1.43 3,867 2 2.7 0.0271 31.6 2.22 3,231 3 4.0 0.0258 31.3 3.20 3,267 4 5.5 0.0301 31.1 3.04 3,120 5 6.6 0.0276 31.3 4.04 3,049

In Table 4 above, 'APP' refers to ammonium phosphate. In Table 4, 'PU' refers to polyurethane foam manufactured without adding inorganic particles (APP).

Table 4 shows the physical properties of polyurethane foam prepared according to Example 5 by adding ammonium phosphate content to a weight ratio of 0.7, 1.4, 2.7, 4.0, 5.5, and 6.6% compared to the polyol solution. As the content of ammonium phosphate increases, the density tends to decrease, the content of inorganic substances remaining during thermal analysis also increases, and the amount of emission also tends to decrease.

Sample No. Contents of APP (per total, %) Contents of Al(OH) ₃ (per total, %) Density
(g/㎤) Height(%) Mresidue Heat 95% confidence level cm % J/g PU 0.0 0.0353 29.5 0.682 3,800 One 4.0 - 0.0258 31.3 3.20 3,2,67 2 4.0 4.0 0.0320 31.0 6.12 3,340

In Table 5 above, 'APP' means ammonium phosphate, and Al(OH) ₃ means aluminum hydroxide. In Table 5, 'PU' refers to polyurethane foam manufactured without adding inorganic particles (APP or aluminum hydroxide).

Table 5 shows polyurethane foam manufactured by adding ammonium phosphate content to 4% compared to the polyol solution according to Example 5, and polyurethane manufactured by adding ammonium phosphate and aluminum hydroxide to 4% according to Example 6. Shows the physical properties of the foam. When only ammonium phosphate was added according to Example 5, the density decreased, but when ammonium phosphate and aluminum hydroxide were added together according to Example 6, the density increased compared to when only ammonium phosphate was added according to Example 5. , it can be seen that the density is lower than that of PU, the calorific value is also small, and the residual weight during thermal analysis is also large.

Sample name density
(g/ ^cm3 ) thermal conductivity
(W/m·k) T50
(℃) Mresidue
(%) Total Heat (J/g) PU-0% 0.0353 0.0210 413.31 0.682 3800.3 AP_6.6% 0.0387 0.2010 454.74 6.54 3261.5 APP_6.6% 0.0276 0.0197 450.18 4.04 3049.97 Al(OH) ₃ 4%
+APP 4% 0.0320 0.0206 450.57 6.122 3347.86 Mg(OH) ₂ 2%
+APP 4% 0.0475 0.0197 488.24 3.72 3418.67

Table 6 shows polyurethane foam (AP_6.6%) manufactured by adding 6% of aluminum phosphate compared to the polyol solution according to Example 4, and polyurethane foam (APP_6.6%) manufactured by adding 6.6% of ammonium phosphate according to Example 5. 6%), polyurethane foam (Al(OH) ₃ 2% + APP 4%) prepared by adding 2% aluminum hydroxide and 4% ammonium phosphate according to Example 6, and 2% magnesium hydroxide according to Example 7 It shows the density and thermal conductivity of polyurethane foam (Mg(OH) ₂ + 4% APP) manufactured by adding 4% of ammonium phosphate, temperature at 50% mass reduction, residual inorganic content, and heat per mass. When aluminum phosphate is added, the density increases, the thermal conductivity is the same as polyurethane foam (PU), and the heat generation amount decreases. It can be seen that when only ammonium phosphate or aluminum hydroxide and ammonium phosphate are added, the density decreases, the thermal conductivity decreases, and the calorific value also decreases. And when magnesium hydroxide and ammonium phosphate are added, the density increases, but the thermal conductivity decreases. It can be seen that the decreases and the calorific value also decreases.

specimen number PU_APP PU_Al(OH) ₃ 5min 10min 5min 10min Total heat release (MJ/m ² ) 16.5 18.3 9.3 10.6 Time exceeding 200 kW/m ² (s) 0 0 Maximum heat release rate (kW/m ² ) 178.38 141.53 141.53 Harmful cracks, holes and melting, etc. has exist has exist Ignition time (s) 6 3

Table 7 shows polyurethane foam (PU_APP) prepared by adding 6.6% of ammonium phosphate compared to the polyol solution according to Example 5, and polyurethane foam (PU_APP) prepared by adding 2% aluminum hydroxide and 4% ammonium phosphate according to Example 6 ( Using a cone calorimeter of PU_Al(OH ₃ )), the total heat release amount, time exceeding 200kW/m ² , maximum heat release rate, presence of cracks and holes, and ignition time are shown. It can be seen that the total heat release is smaller when aluminum hydroxide is added than when only ammonium phosphate is added. In addition, when heated for 5 minutes, the total heat release is 9MJ/m ² , which is equivalent to the flame retardant insulation level of 8MJ/m ² It can be seen that it is close to .

Above, the present invention has been described in detail with reference to preferred embodiments, but the present invention is not limited to the above embodiments, and various modifications may be made by those skilled in the art.

10: Pores in polyurethane foam
20: Cell wall of polyurethane foam
30: Inorganic particles dispersed in the cell walls of polyurethane foam

Claims (17)

delete delete delete delete delete delete (a) forming an isocyanate solution;
(b) forming a polyol solution; and
(c) mixing the isocyanate solution and the polyol solution and polymerizing the isocyanate and polyol to form a porous polyurethane foam,
In at least one of the isocyanate solution and the polyol solution, one or more types of inorganic particles selected from the group consisting of hydroxides and phosphorylates are dispersed,
One or more types of inorganic particles selected from the group consisting of hydroxides and phosphorylates are dispersed in the cell walls surrounding the pores in the porous polyurethane foam,
The hydroxide includes one or more substances selected from the group consisting of aluminum hydroxide and magnesium hydroxide,
The phosphorylate includes one or more substances selected from the group consisting of aluminum phosphate and ammonium phosphate,
In step (c) above,
A metal compound containing at least one material selected from the group consisting of an alkyl tin carboxyl group, an alkyl zinc carboxyl group, an alkyl bismuth carboxyl group, and a mercapto group is mixed with the isocyanate solution and the polyol solution to effect the polymerization reaction,
In step (c) above,
A method for producing porous polyurethane foam, characterized in that the polymerization reaction is achieved by mixing methyleformate with the isocyanate solution and the polyol solution.
delete delete delete delete The method of claim 7, wherein the inorganic particles include particles larger than 10 nm and smaller than 100 μm.
The method of claim 7, wherein the isocyanate solution is methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and xylylene diisocyanate (XDI). ) A method for producing porous polyurethane foam, characterized in that it includes one or more materials selected from the group consisting of.
The method of claim 7, wherein the polyol solution is selected from the group consisting of diethylene glycol, polyethylene glycol, dipropylene glycol, polypropylene glycol, polyester, polyether, and polytetramethylene ether glycol (PTMEG; Polytetramethylene Ether Glycol). A method for producing porous polyurethane foam, characterized in that it contains one or more types of materials.
The method of claim 7, wherein in step (c),
The polymerization is carried out by mixing one or more amine compounds selected from the group consisting of triethylenediamine, dimethylcyclohexylamine, dimethylethanolamine, and 1,4-diazabicyclooctane (DABCO) with the isocyanate solution and the polyol solution. A method for producing porous polyurethane foam, characterized in that the reaction occurs.
delete delete