KR20100137815A - Method for preparing polyisocyanurate foam using liquid nucleating agents and polyisocyanurate foam prepared by the same - Google Patents

Abstract

PURPOSE: A method for preparing polyisocyanurate foam using a liquid nucleating agent and polyisocyanurate foam prepared by the same are provided to reduce the size of foamed cell using a liquid nucleating agent while using a foaming agent and to improve compressive strength and flexural strength. CONSTITUTION: A method for preparing polyisocyanurate foam comprises a step of polymerizing a polyol-based compound and an isocyanate-based compound. A liquid silane compound is used as a nucleating agent for form formation. The content of the liquid silane compound is 0.5 ~ 10 parts by weight based on 100 parts by weight of the polyol-based compound.

Description

Method for preparing polyisocyanurate foam using liquid nucleating agent and polyisocyanurate foam using liquid nucleating agents and polyisocyanurate foam prepared by the same

The present invention relates to a method for producing a polyisocyanurate foam and a polyisocyanurate foam produced thereby, more specifically, the size of the foam cell is smaller than the prior art while using a blowing agent that does not destroy the ozone layer. The present invention relates to a method for producing a polyisocyanurate foam having low thermal conductivity and improved mechanical properties such as compressive strength and a polyisocyanurate foam using the same.

Insulation is a material used to block or reduce heat exchange between spaces to increase single-sided or cooling efficiency. Insulation is widely used in various fields, such as building panels, LNG ship insulators, home appliance packaging or automotive interior materials, generally made of a structure containing pores filled with gas to lower the thermal conductivity. Polyurethane foam, one of such insulation materials, has excellent thermal insulation performance and processability compared to other synthetic resins, and is widely used in the present. However, with the recent tightening of the flame retardant performance on insulation materials, the use of polyisocyanurate foam (PIR foam), which is superior to polyurethane foam, is increasing. The polyisocyanurate foam has a structure including an isocyanurate bond in which three isocyanate groups are bonded to an existing polyurethane foam to form a ring structure. Since polyisocyanurate foam has a ring structure, pyrolysis temperature is very high, such as 300 ° C. or higher, and thermal stability is superior to other heat insulating materials. In addition, it shows very good performance in terms of mechanical strength such as compressive strength and flexural strength.

Polyisocyanurate foam can be prepared by mixing a polyol with an isocyanate, a catalyst, a blowing agent, and the like as the polyurethane foam, and a porous foam is formed due to the foaming gas generated during the reaction. The foaming gas is contained in the cell structure of the polyisocyanurate foam, and it is diffused out over time and the inside of the cell is replaced with air. Since air is generally higher in thermal conductivity than foamed gas, the thermal conductivity of foams is gradually increased over time, resulting in poor thermal insulation performance. Currently used blowing agents include hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and pentanes, and research is being conducted to replace them with water. Currently, most industries use HCFC-141b as a blowing agent, but since such a blowing agent has a problem of destroying the ozone layer, its use is completely banned from 2030. Therefore, in recent years, researches on the development of a clean foaming agent without fear of ozone layer destruction have been actively conducted, and researches on a method of manufacturing a polyurethane foam or a polyisocyanurate foam using the same have also been conducted. However, until now, most of the materials developed as alternative blowing agents are pentane series or water. These materials are known to have poor thermal insulation performance because they have higher thermal conductivity than HCFC or HFC series, which are used in the past, and mechanical properties such as compressive strength and flexural strength are known. It is hard to be used as a heat insulating material due to degradation.

One of the techniques for replacing the blowing agent is a technique of securing the physical properties of the insulating material using a solid additive. Recently, attempts have been made to peel solid additives by dispersing solid additives, such as clay or aerosil, into microols or isocyanates and inserting them between the additive layers. Polyurethane foam incorporating clay or aerosil improves the insulation performance and mechanical strength to some extent, but the interaction between the polyurethane and the solid additive surface is so weak that the bonding force between the solid additive layers cannot be sufficiently overcome. Due to this, the solid additives show a problem of coagulation with each other. In addition, when the solid additive is dispersed in a polyol or an isocyanate, there is a problem that a storage stability problem occurs over time, so that a foam having a uniform cell size is difficult to obtain. Therefore, there is a great need for the development of insulation materials with improved physical properties without having the problem of ozone layer destruction.

Therefore, the first problem to be solved by the present invention is to use a blowing agent that does not affect the ozone layer destruction, and even when the additive is introduced, the aggregation phenomenon between the additives is effectively prevented, has a uniform cell, and compared with the thermal properties and mechanical It is to provide a method for producing a polyisocyanurate foam having excellent strength.

The second problem to be solved by the present invention is to provide a polyisocyanurate foam prepared by the above manufacturing method.

The present invention is made by polymerizing a polyol compound and an isocyanate compound in order to achieve the first object, wherein the liquid silane compound is used as a nucleating agent for foam formation of the polyisocyanurate foam It provides a manufacturing method.

According to one embodiment of the present invention, the content of the liquid silane compound is preferably 0.5 to 10 parts by weight based on 100 parts by weight of the polyol compound.

According to another embodiment of the present invention, in the liquid silane compound, at least one of hydrogen of the silane group may be substituted with a methyl group.

According to another embodiment of the present invention, the liquid silane-based compound may be at least one selected from the group consisting of hexamethyldisilase, hexamethyldisiloxane and dimethoxydimethylsilane.

According to another embodiment of the present invention, the isocyanate compound is at least one selected from the group consisting of polymeric methylene diphenyl diisocyanate, monomeric methylene diphenyl diisocyanate, polymeric toluene diisocyanate and monomeric toluene diisocyanate Can be.

According to another embodiment of the present invention, the polyol-based compound may be a polyester polyol or a polyether polyol.

According to another embodiment of the present invention, the polyester polyol may be polymerized by reacting phthalic anhydride or adipic acid with ethylene oxide, propylene oxide or a mixture thereof.

According to another embodiment of the present invention, the polyether polyol is ethylene glycol, 1,2-propane glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, 2-methyl -1,3-propanediol, glycerol, trimethylolpropane, 1,2,3-hexanetriol, 1,2,4-butanetriol, trimethylolmethane, pentaerythritol, diethylene glycol, triethylene glycol, At least one selected from the group consisting of polyethylene glycol, tripropylene glycol, polypropylene glycol, dibutylene glycol, polybutylene glycol, sorbitol, sucrose, hydroquinone, resorcinol, catechol and bisphenol is ethylene oxide, propylene oxide Or may be polymerized by reacting with a mixture thereof.

According to another embodiment of the present invention, a catalyst is used for the polymerization of the polyol compound and the isocyanate compound, and the catalyst is acetic acid, octanoic acid, 2,4,6-trisdimethylaminomethylphenol, 1,3,5 At least one selected from the group consisting of -tris 3-dimethylamine-propyl hexahydrotriazine and potassium hexanoate.

According to another embodiment of the present invention, a surfactant is used to polymerize the polyol-based compound and the isocyanate-based compound, and the surfactant may inhibit the size growth of the foamed cell formed on the polyisocyanurate foam.

According to another embodiment of the present invention, a blowing agent is used for the polymerization of the polyol compound and the isocyanate compound, and the blowing agent may be at least one selected from the group consisting of cyclopentane, isopentane, normalpentane and water.

According to another embodiment of the present invention, (a) mixing and stirring a polyol compound and a liquid silane compound, (b) mixing a polymerization catalyst, a surfactant and a blowing agent to the mixed liquid obtained in the step (a) It provides a method for producing a polyisocyanurate foam comprising the step of stirring and (c) mixing the isocyanate compound in the liquid mixture obtained in the step (b) and stirring to polymerize the polyisocyanurate.

According to another embodiment of the present invention, the step (a) and (b) is preferably carried out at a temperature of 20 to 40 ℃.

According to another embodiment of the present invention, the step (a) may be performed while gradually increasing the stirring speed in the stirring speed range of 500 to 2,500rpm.

According to another embodiment of the present invention, the step (c) is preferably carried out in a stirring speed range of 2,500 to 5,000rpm.

The present invention provides a polyisocyanurate foam prepared by the above production method in order to achieve the second object.

According to an embodiment of the present invention, the polyisocyanurate foam may further include a flame retardant.

According to another embodiment of the present invention, the foamed cell formed on the polyisocyanurate foam may have a volume ratio of 50 to 90% compared to the case where the liquid silane compound is not used as a nucleating agent under the same polymerization conditions.

Using the manufacturing method of the polyisocyanurate foam according to the present invention, it is possible to reduce the size of the foaming cell by using a liquid nucleating agent while using a blowing agent that does not affect the ozone layer destruction, low thermal conductivity, compression It is possible to produce a polyisocyanurate foam having improved mechanical properties such as strength and flexural strength. The polyisocyanurate foam thus prepared has a significantly lower cell size and thermal conductivity than the polyisocyanurate / clay nanocomposites or polyurethane / clay nanocomposites according to the prior art.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The polyisocyanurate foam according to the present invention is prepared by polymerizing a polyol compound and an isocyanate compound, wherein a liquid silane compound is used as a nucleating agent for foam formation.

The polyisocyanurate foam is a material including an isocyanurate group in the form of three isocyanate groups bonded in a ring structure to a polyurethane foam, which is conventionally used as a short material. Due to this ring structure, polyisocyanurate foam has excellent performance in terms of thermal stability and mechanical strength. The prior art has the effect of reducing the size of the foaming cell through the introduction of a solid additive, that is, a material such as clay or aerosil in the polyol in the production of polyurethane foam, thereby obtaining an effect of improving the thermal insulation performance. However, since the solid additives cause problems of segregation and storage stability when introduced into the polyol, the present invention proposes a technique for introducing a liquid nucleating agent to form a densely and uniformly formed foam cell of the polyisocyanurate foam. The smaller the foam cell formed in the insulation, the better the insulation effect and the higher the mechanical strength. Therefore, in addition to the foaming agent, materials that can help the initial nucleation are added to the polymer to reduce the foam cell size and increase the density of the foam cell. By increasing the physical properties of the heat insulating material can be improved. The liquid nucleus is a liquid substance and refers to a substance which is uniformly dispersed in the polymerization material to aid in nucleation. In the present invention, a liquid silane compound is used.

The nucleating agent used in the present invention is a liquid silane-based compound, for example, compounds such as hexamethyldisilazane (HMDS), hexamethyldisiloxane (hexamethyldisiloxane) and dimethoxydisilane (dimethoxydisilane) may be used, The scope of the present invention is not limited to the above compounds, and any silane-based compound is within the scope of the present invention as long as it forms a liquid phase. In the following Chemical Formulas 1 to 3, structural formulas of the liquid silane compounds are shown in order.

In the present invention, the liquid silane compound used as the nucleating agent is preferably a silane compound in which at least one of hydrogen bonded to silicon of the silane is substituted with a methyl group. Such silane compounds may be advantageously applied to the present invention because they exhibit high stability in the process of being incorporated into the polyol and then stirred. The liquid silane compound is preferably incorporated in the range of 0.5 to 10 parts by weight based on 100 parts by weight of the polyol compound. If the content of the liquid silane-based compound is less than 0.5 parts by weight, the density of the foaming cell formed is too low to ensure sufficient thermal insulation performance and mechanical properties, if it exceeds 10 parts by weight it is difficult to uniformly disperse.

A polyol compound is a substance including a plurality of hydroxyl groups in one molecule, and reacts with an isocyanate compound to generate a urethane bond and to proceed with polymerization. The polyol-based compound used in the present invention may be a polyester polyol or a polyether polyol. The polyester polyol may be prepared by reacting phthalic anhydride or adipic acid with ethylene oxide, propylene oxide, or a mixture thereof to polymerize the polyether polyol. Silver ethylene glycol, 1.2-propane glycol, 1,2-propane glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol ( 1,8-oxtanediol, neopentylglycol, 2-methyl-1,3-propanediol, glycerol, trimethylolpropane, 1 , 2,3-hexanetriol (1,2,3-hexanetriol), 1,2,4-butanetriol (1,2,4-butanetriol), trimethylolmethane, pentaerythriol , Diethyleneglycol, triethyleneglycol, polyethyleneglycol, tripropyleneglyc ol, polypropyleneglycol, dibutyleneglycol, polybutyleneglycol, sorbitol, sucrose, hydroquinone, resorcinol, At least one selected from the group consisting of catechol and bisphenol may be prepared by reacting and polymerizing ethylene oxide, propylene oxide or a mixture thereof.

An isocyanate compound is a substance containing an isocyanate group in a molecule, and the isocyanate group reacts with the hydroxyl group of the polyol compound to form a urethane bond, and also plays a role in forming isocyanurate by reacting and trimerizing three isocyanate groups. Do it. In the present invention, it is advantageous to use a material having a higher number of isocyanate groups than the isocyanate compound generally used for polymerization of polyurethane for isocyanurate formation. Therefore, it is preferable to use a diisocyanate compound having a high NCO index of about 250. Do. In the present invention, polymeric methylene diphenyl diisocyanate (polymeric MDI), monomeric methylene diphenyl diisocyanate (monomeric MDI), polymeric toluene diisocyanate (polymeric TDI) And at least one selected from the group consisting of monomeric toluene diisocyanate (monomeric TDI) may be used as the isocyanate compound.

According to the present invention, a polymerization catalyst, a surfactant, a blowing agent, or a flame retardant may be mixed with the polymer of the polyisocyanurate foam.

The polymerization catalyst promotes trimerization of isocyanates and improves the reaction rate to serve to form isocyanurate groups. In the present invention, the polymerization catalyst is acetic acid, octanoic acid, 2,4,6-trisdimethylaminomethylphenol (2,4,6-tris [(dimethylamino) methyl] phenol), 1,3 , 5-tris 3-dimethylamine-propyl hexahydrotrizine (1,3,5-tris 3-dimethylamine-propyl hexahydrotrizine) and potassium hexanoate (potassium hexanoate) may be at least one selected from the group consisting of.

The blowing agent serves to form a foaming cell in the heat insulating material by generating a gas during the polymerization process. Since the blowing agent is present in the cell after forming the polyisocyanurate foam, it is advantageous to use a material having low thermal conductivity and high stability. Blowing agents used in the present invention cyclopentane (cyclopentne), chlorofluorocarbon (chlorofluorocarbon), isopentane (isopentane), normal pentane (n-pentane), hydrochlorofluorocarbon (hydrochlorofluorocarbon), hydrofluorocarbon (hydrofluorocarbon) ), And at least one selected from the group consisting of water, in particular cyclopentane, water or a mixture thereof, which is a blowing agent that does not contain chlorine, is environmentally advantageous. In addition, the density of the polyisocyanurate foam can be adjusted by adjusting the content of the foaming agent. In the present invention, the density of the polyisocyanurate foam is adjusted to 50 kg / m 3, but the scope of the present invention is limited by the density value. It doesn't work.

The surfactant controls the surface tension at the time of formation of the foam cell to suppress the size of the foam cell from becoming too large and serves to stabilize the formation of the foam cell. In the present invention, it is possible to use various kinds of surfactants known in the art.

As the flame retardant, trischloropropyl phosphate may be used as an additive for improving the flame retardancy of the polyisocyanurate foam which is a heat insulating material, and various kinds of flame retardants known in the art may be used.

In the present invention, conditions such as stirring speed or reaction temperature are important for the polymerization of the polyisocyanurate foam. In order to explain the stirring speed and reaction speed of the preferred conditions, the manufacturing process is shown as follows. First, the polyol compound and the liquid silane compound are mixed and stirred (step (a)), and the polymerization catalyst, the surfactant and the blowing agent are mixed and stirred with the mixed liquid obtained in the step (a) (step (b)), The isocyanate compound is mixed with the mixed solution obtained in step (b) and stirred to polymerize the polyisocyanurate (step (c)).

In the step (a), the stirring rate of the polyol compound and the liquid silane compound is preferably 500 to 2,500 rpm. For uniform dispersion of the polyol compound and the liquid silane compound, the stirring is performed at a low speed of about 500 rpm at the initial stage. Stir for about 15 seconds, and gradually increase the speed to increase the stirring speed to 2,500 rpm later in the stirring. If the stirring is too slow during initial stirring, the viscosity of the polyol compound is high and the viscosity of the liquid silane compound is low, which may cause a problem that the liquid silane compound is not sufficiently dispersed. In addition, when the late stirring speed is stirred at too high a speed, it is difficult to obtain sufficient contact time to cause uniform dispersion between the polyol compound and the liquid silane compound. In addition, step (a) is preferably carried out at a temperature of 20 to 40 ℃. If the advancing temperature is less than 20 ℃ the dispersion between the polyol-based compound and the liquid silane-based compound does not occur sufficiently, on the contrary, if it exceeds 40 ℃, the liquid silane-based compound may evaporate because the volatilization point of the liquid silane-based compound is low.

Preferably, the stirring speed of step (b) is 500 to 2,500 rpm, which is a speed at which the polymerization catalyst, the surfactant, and the blowing agent are uniformly mixed, and if out of this range, each material is unevenly distributed and the poly The physical properties of the isocyanurate foam may be lowered. In addition, the temperature range of step (b) is preferably 20 to 40 ° C. If the temperature is exceeded, the properties of the added material may be changed. In particular, in the case of cyclopentane, a blowing agent, polyisocyanate is volatile. By changing the density of the late form it can cause a change in properties.

The stirring speed of step (c) is preferably 2,500 to 5,000 rpm, which is a rate set so that reaction of the polyol compound and the isocyanate compound and the trimerization reaction of the isocyanates can be made within a sufficiently fast time. Stirring at a rate lower than 2,500 rpm causes a problem that the mixture does not sufficiently mix to smoothly react. On the contrary, when the ratio exceeds 5,000 rpm, the reaction time may be incomplete due to a short contact time between the polyol and the isocyanate. In addition, the reaction temperature of step (c) is preferably 20 to 80 ℃, if less than the above temperature range, the condensation reaction between the polyol compound and the isocyanate compound and the trimerization reaction between isocyanate groups is less likely to occur, on the contrary If the temperature range is exceeded, an excessively fast reaction may be induced, thereby preventing the stabilization of the cell or volatilizing the reactant.

Hereinafter, the present invention will be described in more detail with reference to preferred examples. However, these examples are intended to illustrate the present invention in more detail, it will be apparent to those skilled in the art that the scope of the present invention is not limited thereby.

Example 1

Example 1-1 (mixing of a polyol compound and a liquid silane compound)

3.0 g of hexamethyldisilazane (HMDS), a liquid silane compound, was added to a polyol having a weight of 100 g. Polyol was used as a mixture of polyester polyol (polyether polyol, KFT-200, manufactured by Korea Polyol Co.) and polyester polyol (polyester polyol, POL-1001, manufactured by Aekyung Petrochemical Co.) at a weight ratio of 4: 6. . Since the viscosity of the polyol used is high and the viscosity of the hexamethyldisilazane is low, a low speed of 500 rpm is used at the beginning of the reaction by using a mechanical stirrer in order to be able to be intercalated between the hexamethyldisilase or the polyol compound. The mixture was stirred for 2 minutes (1 step agitation), followed by stirring for 30 seconds at a high speed of 2,500 rpm for 2 minutes at 1,000 rpm (2 step agitation).

Example 1-2

A polyisocyanurate foam was prepared by mixing and polymerizing a catalyst, distilled water and a blowing agent in the mixture obtained according to Example 1-1. In this case, the catalyst used was potassium hexanoate (H 977), and a blowing agent was obtained by polymerizing cyclopentane and water in a 5: 1 weight ratio. The amount of blowing agent used was an amount to adjust the density of the polyisocyanurate foam to about 50 kg / m 3. For the reaction of the polyol compound and the diisocyanate, the mixture was stirred at 5,000 rpm for 15 seconds using a mechanical stirring apparatus, and then prepared in an open mold.

Example 2

Polyisocyanurate foam was prepared in the same manner as in Example 1 except that hexamethyldisilazane (HMDS) was used instead of hexamethyldisilazane (HMDS).

Example 3

Polyisocyanurate foam was prepared in the same manner as in Example 1, except that dimethoxydimethylsilane was used instead of hexamethyldisilazane (HMDS).

Comparative Example 1

Comparative Example 1-1 ( Preparation of Organic Clay-Containing Polymeric MDI)

It was dried for 24 hours in a vacuum oven to remove the water contained in the organic clay containing a hydroxyl group (30B clay, fighting clay company (manufactured by Southern Clay Co.).) Next, 100 parts by weight of the polyol used in Example 1 160 parts by weight of polymeric 4,4-diphenyldetane diisocyanate (M50, manufactured by BASF) and 4.8 parts by weight of solid nucleating agent 30B clay were added thereto, followed by a water bath in an oil bath maintained at a reaction temperature of 60 ° C. The polymeric MDI and clay were uniformly mixed and stirred for 2 hours at a speed of 3,000 rpm using a mechanical stirrer in order to proceed with a smooth reaction.

Comparative Example 1-2 (Preparation of 30B clay-polyisocyanurate nanocomposite)

The clay-polyisocyanurate nanocomposite was prepared by adding 160 g of organic clay-containing polymeric MDI obtained in Comparative Example 1-1, 100 g of polyol, a catalyst and a surfactant, and reacting at room temperature. Polymeric 4,4'-diphenylmethane diisocyanate containing the organic clay was added in excess of 5% by weight of the stoichiometric ratio, and stirred for 5 seconds at 5,000 rpm using a mechanical stirring apparatus for the reaction.

Comparative Example 2

Polyisocyanurate foam was prepared in the same manner as in Example 1, except that a liquid nucleating agent such as hexamethyldisilazane or a solid nucleating agent was not added.

Experimental Example 1 (Comparison of Morphology of Foam Cell with Nucleating Agent)

In order to observe the morphology of the foaming cell, each of the polyisocyanurate foam nanocomposites and the polycysocyanurate foam specimens prepared according to Examples 1 to 3 and Comparative Examples 1 to 2 were each 30 mm (width) × After cutting into 30 mm (height) x 80 mm (height), the specimens were cut into liquid nitrogen, and the cross section of the cell was measured by an electron scanning microscope (SEM). 1 to 5 are cross-sectional SEM photographs of specimens prepared according to Examples 1 to 3 and Comparative Examples 1 to 2, respectively, and FIG. 6 shows a comparison of the average size of the foam cells. 1 to 6, the specimens of the embodiment of the liquid nucleating agent is smaller than the size of the foam cell than the specimen without the liquid nucleating agent, in particular the cell of Example 1 using hexamethyldisilazane as the liquid nucleating agent It can be seen that the size is the smallest. This is because hexamethyldisilazane is a molecule having a very high silane ratio and a high methyl group ratio, and the more the methyl group is substituted in the silane compound, the lower the van der Waals force and the lower the surface tension. It is believed that smaller foam cells are formed densely by preventing the phenomenon.

Experimental Example 2 (thermal conductivity test according to the addition of nucleating agent)

In order to compare the thermal insulation performance of the polyisocyanurate foam nanocomposite and the polysisocyanurate foam prepared according to Examples 1 to 3 and Comparative Examples 1 to 2, thermal conductivity was measured according to ASTM C518. It measured, and the result is shown in FIG. Referring to FIG. 7, it can be seen that the thermal conductivity of the embodiments in which the liquid nucleating agent is applied is lower than that of Comparative Example 2 in which the liquid nucleating agent is not applied. In addition, the polyisocyanurate foam prepared according to Example 1 exhibits the lowest thermal conductivity. Since the polyisocyanurate foam has a smaller thermal conductivity as the cell size decreases like the polyurethane foam, it can be seen that the tendency of the low thermal conductivity becomes more pronounced when a molecule having a high methyl group ratio is added.

Experimental Example 3 (Compressive Strength Test According to Nucleating Agent Addition)

The compressive strength of the polyisocyanurate foam nanocomposite and polyisocyanurate foam prepared according to Examples 1 to 3 and Comparative Examples 1 to 2 was measured according to ASTM D 1621, and the results were obtained. Is shown in FIG. 8. Polyisocyanurate foams prepared according to Example 3 exhibit the highest compressive strength. It is believed that this is because the cell size of the polyisocyanurate foam is further reduced and densely formed to better withstand the forces applied.

From the comparative experiments of the Examples and Comparative Examples described above, it was confirmed that the polycysocyanurate foams according to Examples 1 to 3 had lower thermal conductivity than the polycysocyanurate foam of Comparative Example 2. This is a physical property related to the thermal insulation performance, which is the most important physical property when the polyisocyanurate foam is used as the heat insulating material, it can be seen that the heat insulating performance of the heat insulating material is improved when the liquid silane-based compound is used as the nucleating agent according to the present invention. Comparative Example 1 exhibits properties similar to those of some examples in terms of thermal conductivity, but it is not preferable when the solid additives are mixed because they show disadvantageous results in terms of storage stability and the like. As a result of compressive strength measurement, some examples were measured to be more disadvantageous than comparative examples, but compressive strength is a function accompanying the insulation function, which is a fundamental function of the insulation, and both Examples and Comparative Examples exhibit sufficient physical properties to be used as insulation. Showed results.

1 is an electron scanning micrograph of the polyisocyanurate foam prepared according to Example 1. FIG.

2 is an electron scanning micrograph of the polyisocyanurate foam prepared according to Example 2. FIG.

3 is an electron scanning micrograph of the polyisocyanurate foam prepared according to Example 3. FIG.

4 is an electron micrograph of the polyisocyanurate nanocomposite prepared according to Comparative Example 1.

5 is an electron scanning micrograph of the polyisocyanurate foam prepared according to Comparative Example 2.

FIG. 6 shows cell sizes of polyisocyanurate foam and polyisocyanurate foam nanocomposite prepared according to Examples 1 to 3 and Comparative Examples 1 to 2, respectively.

7 is a thermal conductivity graph of polyisocyanurate foam and polyisocyanurate foam nanocomposites prepared according to Examples 1 to 3 and Comparative Examples 1 to 2.

8 is a graph of compressive strength of polyisocyanurate foam and polyisocyanurate foam nanocomposite prepared according to Examples 1 to 3 and Comparative Examples 1 to 2.

Claims (18)

A method for producing a polyisocyanurate foam by polymerizing a polyol compound and an isocyanate compound, wherein the liquid silane compound is used as a nucleating agent for foam formation. The method of claim 1, The content of the liquid silane compound is a polyisocyanurate foam production method, characterized in that 0.5 to 10 parts by weight based on 100 parts by weight of the polyol compound. The method of claim 1, The liquid silane compound is a method for producing a polyisocyanurate foam, characterized in that at least one of the hydrogen of the silane group is substituted with a methyl group. The method of claim 1, The liquid silane compound is a method for producing a polyisocyanurate foam, characterized in that at least one selected from the group consisting of hexamethyldisilase, hexamethyldisiloxane and dimethoxydimethylsilane. The method of claim 1, The isocyanate compound is polyisocyanate, characterized in that it comprises at least one selected from the group consisting of polymeric methylene diphenyl diisocyanate, monomeric methylene diphenyl diisocyanate, polymeric toluene diisocyanate and monomeric toluene diisocyanate Method for producing late foam. The method of claim 1, The polyol-based compound is a method for producing a polyisocyanurate foam, characterized in that the polyester polyol or polyether polyol. The method of claim 6, The polyester polyol is a method for producing a polyisocyanurate foam, characterized in that the polymerization by reacting phthalic anhydride or adipic acid with ethylene oxide, propylene oxide or a mixture thereof. The method of claim 6, The polyether polyol may be ethylene glycol, 1,2-propane glycol, butylene glycol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, 2-methyl-1,3-propanediol, glycerol, Trimethylolpropane, 1,2,3-hexanetriol, 1,2,4-butanetriol, trimethylolmethane, pentaerythritol, diethylene glycol, triethylene glycol, polyethylene glycol, tripropylene glycol, polypropylene Polymerized by reacting at least one selected from the group consisting of glycol, dibutylene glycol, polybutylene glycol, sorbitol, sucrose, hydroquinone, resorcinol, catechol and bisphenol with ethylene oxide, propylene oxide or mixtures thereof Method for producing a polyisocyanurate foam, characterized in that. The method of claim 1, A catalyst is used for the polymerization of the polyol compound and the isocyanate compound, and the catalyst is acetic acid, octanoic acid, 2,4,6-trisdimethylaminomethylphenol, 1,3,5-tris 3-dimethylamine-propyl hexahydro Method for producing a polyisocyanurate foam, characterized in that at least one selected from the group consisting of triazine and potassium hexanoate. The method of claim 1, In the polymerization of the polyol-based compound and the isocyanate-based compound, a surfactant is used, and the surfactant inhibits the size growth of the foam cell formed on the polyisocyanurate foam. . The method of claim 1, A foaming agent is used for the polymerization of the polyol compound and the isocyanate compound, and the blowing agent is at least one selected from the group consisting of cyclopentane, isopentane, normal pentane and water. (a) mixing and stirring the polyol compound and the liquid silane compound; (b) mixing and stirring a polymerization catalyst, a surfactant, and a blowing agent with the mixed solution obtained in the step (a); And (c) mixing the isocyanate compound with the mixed solution obtained in the step (b) and stirring to polymerize the polyisocyanurate. The method of claim 12, Step (a) and (b) is a method for producing a polyisocyanurate foam, characterized in that proceeding at a temperature of 20 to 40 ℃. The method of claim 12, The step (a) is a method for producing a polyisocyanurate foam, characterized in that proceeding gradually increasing the stirring speed in the stirring speed range of 500 to 2,500rpm. The method of claim 12, The step (c) is a method for producing a polyisocyanurate foam, characterized in that proceeds in a stirring speed range of 2,500 to 5,000rpm. Polyisocyanurate foam produced by the method of any one of claims 1 to 15. The method of claim 16, Polyisocyanurate foam further comprises a flame retardant. The method of claim 16, The foam cell formed in the polyisocyanurate foam, polyisocyanurate foam, characterized in that the volume ratio of 50 to 90% compared to the case where the liquid silane compound is not used as a nucleating agent under the same polymerization conditions.

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