JPH0987408A - Heat insulating foam and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat insulating foam having high heat insulating property by early fixing carbon dioxide in a heat-insulating foam. SOLUTION: This heat insulating foam comprises an expandable urethane resin composition containing an epoxide and a carbonate component produced by reacting the epoxide with carbon dioxide and satisfies the formula (molar concentration of epoxy group)>(molar concentration of carbon dioxide + molar concentration of isocyanate group) in the relationship of average molar concentrations of carbon dioxide, isocyanate group and epoxy group. The production of the foam is carried out by mixing at least one of a retardant activation type resinifying catalyst composition and a retardant activation type resinifying material composition with raw materials of the urethane resin. Thereby, advancing degree of the resin forming reaction is increased and the amount of isocyanate group left immediately after the urethane resinification reaction is decreased and fixing reaction of carbon dioxide due to the epoxide is promoted.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a refrigerator, a freezer,
The present invention relates to a heat insulating foam used for building materials and the like and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, environmental damage due to CFCs such as ozone layer depletion or global warming has become a social problem, and reduction of specific CFCs (such as trichloromonofluoromethane), which is a foaming agent for foamed insulation such as rigid urethane foam, has been reduced. Or the abolition is a big issue. Therefore, as the foaming agent, a substance having a small ozone depletion coefficient, for example, 1,1-
Dichloro-1-fluoroethane (HCFC-141
b), 1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and the like are used to form a polyurethane foam. In addition, a method for producing a polyurethane foam using a hydrocarbon as a blowing agent, such as cyclopentane, which causes less ozone layer depletion or environmental damage such as global warming, is also well known (eg, May 1993, Preliminary Report of Polyurethane International Forum 93). Shu 197, Gerhard Heilich and Yoshinori Kihara, “Pentane Foamed Hard Urethane Foam”. Usually, in order to improve the flowability at the time of foaming, water is added to a hydrocarbon such as cyclopentane and used as a foaming agent. In that case, carbon dioxide generated from water at the time of foaming,
It has high thermal conductivity and reduces the heat insulating performance of the heat insulating foam obtained. Therefore, it has been proposed to fix this carbon dioxide to obtain high heat insulation. Also, before this,
It has been proposed that carbon dioxide be immobilized by reaction with an epoxide during the production of a heat-insulating foam by water-foaming to obtain a foam in which the pressure inside the closed cells is reduced (Japanese Patent Laid-Open No. 6-3).
22166).

[0003]

As described above, carbon dioxide, which has a high thermal conductivity, is generated by using hydrocarbons and water, which have a small load on the global environmental problems such as ozone depletion and global warming, as blowing agents. In the method of fixing and obtaining a heat insulating foam having a high heat insulating property for refrigerators and building materials, urethane, which is easy to foam in situ, is preferably used as a resin in many cases. However, the reaction of isocyanate, which is the raw material of urethane resin, with epoxide reduces the amount of epoxide that originally reacts with carbon dioxide and immobilizes it, which delays the progress of carbon dioxide immobilization, resulting in thermal conductivity. There was a problem that the decrease of the price did not proceed. It is an object of the present invention to provide a heat insulating foam which has a high heat insulating property and is capable of fixing carbon dioxide in the heat insulating foam at an early stage.

[0004]

In order to solve the above-mentioned object, the heat insulating foam of the present invention comprises a urethane foam resin composition containing an epoxide and a carbonate component formed by reacting the epoxide with carbon dioxide. And the average molar concentration of carbon dioxide, the isocyanate group, and the epoxy group in the urethane resin composition after foam molding is epoxy group molar concentration> carbon dioxide molar concentration + isocyanate group molar concentration. Is configured to be.

The method for producing a heat insulating foam of the present invention is
A method for producing a heat-insulating foam comprising a urethane foam resin composition containing a carbonate component formed by reaction of epoxide or the carbon dioxide generated after foaming, which is a delayed activation resinification catalyst. By mixing at least one of the composition and the delayed activation type resin material composition with the raw material of the urethane resin, the progress degree of the urethane resin forming reaction is increased, and the isocyanate group remaining immediately after the completion of the resinification reaction is increased. Reduce the amount,
It promotes the carbon dioxide fixing reaction by the epoxide. At this time, it is preferable to use a delayed activation type resinification catalyst composition as the resinization catalyst and to use an epoxide that vaporizes at the time of foaming at a boiling point of 70 ° C. or less as the epoxide. Further, it is preferable to use propylene oxide or 1,2-epoxybutane as the epoxide.

Further, in the method for producing a heat insulating foam of the present invention, in addition to the urethane catalyst as the resinification catalyst for the urethane resin composition, a powder containing a catalyst for activating the resinification reaction rather than the urethane catalyst. Alternatively, it is preferable to use heat-expandable microcapsules together as a delayed activation type resinification catalyst composition. Further, in addition to the polyol as the raw material of the urethane resin, powder or heat-expandable microcapsules containing alcohol having a higher reactivity with the isocyanate component as the raw material of the urethane resin than the polyol is a delayed activation type. It is preferably used together as a resinified material composition. In addition to the isocyanate as the raw material of the urethane resin, a blocked isocyanate of the isocyanate having a higher reactivity with the polyol as the raw material of the urethane resin than the isocyanate has a delayed activity. It is preferable to use it together as a chemical resinized material composition.

The heat insulating foam of the present invention comprises an epoxide and a carbon dioxide formed by reacting the epoxide with carbon dioxide.
A urethane foam resin composition containing a component, after foam molding, carbon dioxide in the urethane resin composition,
The relationship between the average molar concentrations of the isocyanate group and the epoxy group is that the epoxy group molar concentration> carbon dioxide molar concentration + isocyanate group molar concentration. The heat-insulating foam of the present invention is formed by mixing and foaming a polyol, an isocyanate, a urethane catalyst, a carbon dioxide fixing catalyst, a foam stabilizer, a foaming agent and the like. Here, the carbon dioxide-immobilized catalyst has a function of promoting the reaction between carbon dioxide and the epoxide. In many cases, an onium salt alone or a combination of a metal halide and / or an organotin compound and an onium salt is used. Many metal halides and organotin compounds act as urethane catalysts.

It is considered that the following three chemical reactions proceed in parallel in the process of forming the urethane resin foam which fixes carbon dioxide generated after foaming. A) Urethane formation reaction (polyol and polyisocyanate)
Reaction) B) side reaction (reaction between isocyanate and epoxide) C) carbon dioxide immobilization reaction (reaction between carbon dioxide and epoxide) Reaction rates are in the order of A>B> C. However, the reaction of B consumes the epoxide necessary for fixing carbon dioxide, and if the reaction proceeds, the fixation of carbon dioxide will be inhibited to that extent. What is important is that if the amount of isocyanate remaining in the urethane reaction of A increases, the side reaction of B also increases and the carbon dioxide immobilization reaction of C is suppressed. However, in the heat-insulating foam of the present invention, since the epoxy group molar concentration> carbon dioxide molar concentration + isocyanate group molar concentration, immediately after foam molding, all the isocyanate remaining in the reaction of A is epoxide. Even if it reacts,
An amount of epoxide capable of immobilizing all carbon dioxide is present in the insulating foam. Therefore, most of the carbon dioxide can be immobilized over time, and a heat insulating foam having excellent heat insulating properties can be obtained.

The method for producing a heat insulating foam of the present invention is
At least one of 1) the delayed activation type resin-ized catalyst composition and 2) the delayed activation type resin-ized material composition is used, whereby the progress degree of the resin forming reaction of the urethane foam resin composition can be enhanced. It is a feature. As a result, the residual isocyanate groups are reduced. The delayed activation resinification catalyst composition and the delayed activation resinification material composition both have a urethane reaction, a polyol,
When the amount of isocyanate decreases and the efficiency of resin formation decreases, the progress of the urethane reaction is promoted and the amount of residual isocyanate is reduced. If the urethane reaction proceeds rapidly from the beginning, the remaining isocyanate
However, the time from the mixing of the raw materials of each heat insulating foam to the foaming becomes too short, and the filling property becomes poor when forming a heat insulating body such as a refrigerator. The important point of the production method of the present invention is that in order to prevent the filling property from being deteriorated, the urethane reaction proceeds with normal reactivity until the middle of the reaction,
It is the point that the reactivity is increased when the amount of the isocyanate decreases, and the amount of the residual isocyanate decreases.

The delayed activation type resin-forming catalyst composition refers to a composition having a resin-forming catalytic action such that the catalytic activity becomes higher along the progress of the urethane reaction. Specifically, it corresponds to a) a usual delayed type urethane catalyst.
Therefore, as a preferred embodiment, b) urethane catalysts having different reactivity are used, and in addition to the catalyst having relatively low catalytic activity, the remaining catalyst having relatively high catalytic activity is dispersed or adsorbed in the powder. Alternatively, they are encapsulated in thermal expansion type microcapsules. In this case, the powder or microcapsules containing the catalyst having a relatively high catalytic activity corresponds to the delayed activation resinized catalyst composition. In the case of b, the catalyst having a relatively low catalytic activity shows catalytic activity from the beginning, but the one adsorbed and dispersed in the powder desorbs the powder at a high temperature or melts the powder, so that the catalyst is exposed to the outside. Come out. Further, the heat-expandable microcapsules encapsulated therein have high catalytic activity when the microcapsules expand due to heat generated by the progress of the urethane reaction and the catalyst comes out. Thus, in both a and b, the catalytic activity becomes high during the resin forming reaction, so that the residual rate of the isocyanate involved in the resin forming reaction becomes low.

The delayed activation type resin material composition refers to a resin material composition whose reactivity increases from the middle as the urethane reaction proceeds. This delayed activation type resin material composition may contain a compound having an alcohol that reacts to form urethane, or may contain a compound having an isocyanate group. The delayed activation type resin material composition having an alcohol contained an alcohol having a higher reactivity with isocyanate than a polyol dispersed in a powder or encapsulated in a thermal expansion type microcapsule. It is a composition. When such a composition is used, the polyol having a relatively low reactivity is involved in the formation of the urethane resin from the beginning, and the reactivity becomes relatively low when the residual amount of the polyol and the isocyanate decreases. Since high-alcohol comes out from the powder or the microcapsules, the reaction is promoted and the residual isocyanate is reduced.

Further, as the delayed activation type resin-ized material composition having an isocyanate group, a blocked isocyanate which is an isocyanate having a relatively high reactivity with a polyol relative to an isocyanate used. It is preferable that it is a composition containing. Of course, the isocyanate having relatively high reactivity, which is dispersed in powder or enclosed in microcapsules, also has an action as the delayed activation type resin material composition. When these are used, the isocyanate, which has a relatively low reactivity from the initial stage of the urethane formation reaction, is involved in the urethane resin formation. However, when the reaction proceeds and the amount of polyol and isocyanate decreases, relatively high active isocyanate is released from the powder or the heat-expandable microcapsules, or blocked. The efficiency of resin formation is increased because the isocyanate is unblocked to generate highly reactive free isocyanate groups. Thus, less isocyanate is left. When a blocked isocyanate is used, it can be added to the polyol premix. When the blocked isocyanate is added to the polyol premix, the reaction starts from a state where it is well mixed with the polyol, so that the urethane reaction can proceed more efficiently.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described based on specific examples. The heat-insulating foam of the present invention is a foamed urethane resin composition containing an epoxide and a carbonate component formed by the reaction of the epoxide with carbon dioxide as described above. The relationship between the average molar concentrations of carbon, the isocyanate group, and the epoxide group is epoxy group molar concentration> carbon dioxide molar concentration + isocyanate group molar concentration. The residual amount of epoxide groups in the foam can be determined by extracting from the foam with a suitable solvent and analyzing by liquid chromatography. The residual amount of the isocyanate group can be determined by measuring the infrared absorption spectrum of the foam section, and the carbon dioxide can be determined by analyzing the gas released from the foam piece by gas chromatography. it can.

Further, as described above, the heat insulating foam can be easily manufactured by the method of manufacturing the heat insulating foam of the present invention. That is, by using at least one of the delayed activation type resin-forming catalyst composition and the delayed activation type resin-ized material composition, the progress degree of the resin forming reaction of the foamed urethane resin composition is increased to enhance the resin forming reaction. The amount of isocyanate remaining immediately after the end is reduced. As a result, the reaction between carbon dioxide and the epoxide is promoted, carbon dioxide having high thermal conductivity is removed, and high heat insulation is realized. As described above, the delayed activation resinification catalyst composition contains a urethane catalyst, and the delayed activation resinification material composition contains a compound having an alcohol which reacts to form urethane, and an isocyanate. It may include a compound having a group. As described above, these compositions have the effect of increasing the activity of the urethane resin forming reaction during the reaction and reducing the amount of residual isocyanate. As a result, the reaction between the epoxide and the isocyanate is suppressed, and the fixation of carbon dioxide by the epoxide proceeds efficiently.

As the delayed activation type resin-forming catalyst composition,
Piperazine as a urethane catalyst, which has a delay effect by itself,
There are cyclic amine compounds, which are relatively weak catalysts represented by morpholine derivatives, and tertiary amine organic acid block compounds. For example, as the cyclic amine compound, N-methyl-N '-(2-dimethylamino) ethylpiperazine,
1,2-dimethylimidazole and the like. As the tertiary amine organic acid block, many catalysts are available, and for example, Kaolizer-NO. 55,
There are 100, 160, etc. Also, due to the temperature sensitivity, organotin catalysts such as dibutyltin thiocarboxylate and dioctyltin thiocarboxylate can be used in a small amount so that the initial activity does not become too high, so that high activity in the latter stage of the reaction can be obtained. Can be used. An amino alcohol type urethane catalyst can also be used in combination as a relatively mild catalyst. In this case, after acting as a urethane catalyst, it reacts with the isocyanate and is taken into the resin, so that the activity is decreased, and the catalytic action for the side reaction between the isocyanate and the epoxide becomes smaller, which is more preferable.

When the above catalyst is used, it is particularly preferable to use an epoxide having a boiling point of 70 ° C. or less and which is vaporized by the heat of reaction accompanying the progress of the urethane reaction.
This is because when the epoxide is vaporized, it is separated from the liquid isocyanate and the side reaction with the isocyanate hardly proceeds. As a result, the loss of epoxide is reduced, and the fixation of carbon dioxide, which has high thermal conductivity, proceeds efficiently. In this case, as the epoxide, if the boiling point is high, the rate of vaporization becomes small and the effect becomes small. As described above, the boiling point is preferably about 70 ° C. or lower, and specifically, ethylene oxide (boiling point 11 ° C.), propylene oxide (boiling point 34 ° C.), 1,2-epoxybutane (boiling point 63 ° C.), cis-2,3-epoxybutane ( Boiling point 60
℃), trans 2,3-epoxy butane (boiling point 54
C.), butadiene monooxide (boiling point 65.degree. C.), isobutylene oxide (boiling point 52.degree. C.) and the like. Above all,
Propylene oxide and 1,2-epoxybutane are particularly preferable because of their high reactivity with carbon dioxide and their easy availability. In addition to the above-mentioned catalyst, the delayed activation resinized catalyst composition was a) one in which a catalyst having a high relative catalytic activity was dispersed in powder, and b) a thermal expansion microcapsule. There is a form. In this case, it is preferable to use a urethane catalyst having a relatively low catalytic activity in combination with the delayed activation resin catalyst composition. As the urethane catalyst having relatively low catalytic activity, an amino alcohol type urethane catalyst or the like can be used in addition to the cyclic amine compound and the tertiary amine organic acid block. As described above, any urethane catalyst can be used as long as it foams at an appropriate rate to form a foam.

On the other hand, as a relatively highly active catalyst contained in the powder or encapsulated in the heat-expandable microcapsules, tetramethylhexane-1,6-diamine,
Amine-based strong catalysts such as pentamethyldiethylenetriamine, tetramethylguanidine, triethylenediamine, bis (2-dimethylaminoethyl) ether are used. Since these also promote side reactions, dibutyltin dilaurate, which has a small contribution to side reactions, and metal halides such as zinc chloride are preferable. Of course, it is practical to control the reaction rate by combining a plurality of these catalysts. Further, the activity level can be adjusted by the amount of catalyst. For example, a small amount of dibutyltin dilaurate is used as a catalyst having a relatively low activity, and a large amount of dibutyltin laurate is also encapsulated in a thermally expandable microcapsule as a catalyst composition having a relatively high activity. You can also Alternatively, dispersing a large amount of weak catalyst in powder or encapsulating it in heat-expandable microcapsules is also effective in making the resinification reaction in the latter stage of the reaction highly active.

In the delayed activation type resinification catalyst composition as a powder containing a urethane catalyst, the powder is
There is no particular limitation as long as it does not react directly with the catalyst and does not interfere with the urethane reaction or carbon dioxide fixing reaction. But,
Since a resin component is more preferable for reducing the thermal conductivity, solid alcohol or the like is preferable. In that case, since it will be dissolved finally when mixed with the premix containing the polyol, it is preferable to mix the solid alcohol powder containing the catalyst with the isocyanate immediately after mixing. Alternatively, a solid alcohol powder containing a catalyst is dispersed in a hydrocarbon, which is a foaming agent having a relatively small dissolving power, a premix containing a polyol, and an isocyanate are mixed at the same time. It is preferable to perform foam molding. Needless to say, the delayed activation resinification catalyst composition may be prepared by adsorbing the above urethane catalyst on an adsorbent such as molecular sieve or silica gel. Further, as the delayed activation type resin-forming catalyst composition, the microcapsule having the urethane catalyst as the core was described, and the preparation was made by Suedo Kida, “Polymer”, vol.
It can be similarly carried out mainly by using the in situ method as disclosed in the monthly issue, pages 248-251, 1991. The thermoplastic resin used for the wall material of the microcapsules is preferably a vinylidene chloride, acrylonitrile, an acrylic acid ester, and a copolymer resin containing one or more selected from methacrylic acid ester as a main component, which has a thermal expansion property. Copolymers with good and excellent molding properties are desirable. Those which can be crosslinked by a curing agent after being thermally expanded and whose hardness and thermal deformability can be enhanced are more preferable.

The delayed activation type resin material composition of the present invention may contain a compound having an alcohol forming urethane or a compound having an isocyanate group as described above. When an alcohol is contained, it is necessary to have a higher reactivity with an isocyanate than a polyol. Therefore, a primary alcohol having a low viscosity is most preferable, and a methanol, an ethanol, a propanol, an isopropanol is preferable. And butanol are used. Since these have a boiling point of about 100 ° C. or less, they are more effective because they boil at a high temperature to destroy the thermally expanded capsule.
Of course, by inserting another foaming agent in the microcapsules, the same effect can be obtained even when alcohol having a high boiling point is used. As in the case of the urethane catalyst described above, these alcohols function as a delayed activation type resin material composition by being adsorbed on an adsorbent or used as the core of a thermally expandable microcapsule.

Whether the delayed activation type resin material composition has an isocyanate group or contains an adsorbent which is adsorbed by an adsorbent or becomes a core of a heat-expandable microcapsule,
As in the case of the alcohol described above, the function is exhibited and the progress of the urethane reaction is increased. However, it is more preferable to use a blocked isocyanate of a relatively highly reactive isocyanate as the delayed activation type resin material composition. Blocked isocyanate is a compound in which phenol, oxime and the like are bonded to isocyanate,
At high temperatures, these compounds dissociate and give
To produce a radical. Therefore, when a highly active isocyanate is generated during the reaction, the progress of the urethane reaction is increased.
Further, when the temperature is lowered to around room temperature, blocked isocyanate is generated again, so that there is an effect that side reaction between the isocyanate and the epoxide is also suppressed. Further, the blocked isocyanate does not react with the polyol at a low temperature, so that it can be mixed with the polyol to form a premix. In this case, the isocyanate generated at a high temperature is mixed well with the polyol. Therefore, the degree of progress of the urethane reaction is increased, which is preferable.

The isocyanate contained in the delayed activation type resin material composition must have a higher reaction activity with polyol than the isocyanate which is the main component other than the composition used as the urethane material. I have to. In practice, the reactivity in the presence of the polyol used and the catalyst used may be confirmed, and a more active isocyanate may be contained in the delayed activation type resin material composition. It is also possible to make a decision by referring to the reaction activity of a typical isocyanate. Generally, m-phenylene diisocyanate to p-phenylene diisocyanate>
It is known that 4,4-diphenylmethane diisocyanate> 2,6-tolylene diisocyanate> 2,4-tolylene diisocyanate is in that order.

Examples of the onium salt of the carbon dioxide-immobilized catalyst used in the method for producing the heat-insulating foam of the present invention include tetrabutylammonium bromide, tetrabutylammonium iodide, tetrabutylammonium chloride, tetraethylammonium bromide,
Tetraethylammonium iodide, tetraethylammonium chloride, benzylethylammonium chloride, benzylethylammonium bromide,
There are butylpyridinium bromide, tetrabutylphosphonium bromide, and tetraphenylphosphonium chloride. Further, as an organotin compound used for the carbon dioxide-immobilized catalyst, dibutyltin dilaurate is used.
, Dioctyltin dibasate, dibutyltin diacetate and the like. Examples of the metal halide used for the carbon dioxide fixed catalyst include zinc chloride, zinc bromide, zinc iodide, copper chloride, iron chloride, cobalt chloride, manganese chloride, chromium chloride, lithium bromide and lithium chloride. Further, halides of sodium and potassium are also used. In addition to halides, complexes of zinc and transition metals can also be used in combination with onium salts. As already mentioned, many of tin, zinc and transition metal salts, notably as a representative example of dibutyltin dilaurate, act not only as a carbon dioxide fixing catalyst but also as a urethane reaction catalyst.

As the blowing agent other than water used in the present invention, cyclopentane (molecular weight 70.1
4), cyclohexane (molecular weight 84.16), cyclohexene (molecular weight 82.15), 1,4-cyclohexadiene (molecular weight 80.13), 1,3-cyclohexadiene (molecular weight 80.13), quadcyclane (molecular weight) 9
2.14) and benzene which is an aromatic compound (molecular weight 7
8.11), fluorobenzene (molecular weight 96.1), chlorobenzene (molecular weight 13.56) and the like are preferable. Further, fluorides such as fluorinated hydrocarbons and fluorinated ethers, and cyclic ethers such as tetrahydrofuran and 1,3-dioxolane are also preferably used. Furthermore, iodinated fluorohydrocarbons such as fluorinated hydrocarbons, trifluoromethyl iodide, heptafluoropropyl iodide and the like can also be used. In particular, iodinated fluorohydrocarbon is preferable because it has a low thermal conductivity and a fire extinguishing action. Further, it is needless to say that the use of other foaming agents is not particularly limited, and the fixation of carbon dioxide is promoted by the present invention.

In the following specific examples, cyclopentane was used as the foaming agent, and TY- manufactured by Shin-Etsu Chemical Co., Ltd. was used as the foam stabilizer A.
19. Polyol A was an aromatic amine-based polyether polyol having a hydroxyl value of 450 mgKOH / g, and polyisocyanate A was an isocyanate having an amine equivalent of 140.

Example 1 In this example, an organic tin catalyst, dibutyltin laurate, was used as a delayed activation type resin-forming catalyst composition, and an alcohol amine type urethane catalyst (urethane catalyst KLP-200 manufactured by Kao Corporation). ) In a weight ratio of 1:59 and a boiling point of 34 as the epoxide.
Adiabatic foams were formed with each of the propylene oxides at ° C. The weight ratio of the raw materials used is as follows.
Polyol A / foam stabilizer A / delayed activation type resin-forming catalyst composition / tetrabutylammonium bromide / propylene oxide / cyclopentane / water / isocyanate = 10
0/3/3/10/11/11/7/7/128. First, the above raw materials except isocyanate were mixed to form a premix, and isocyanate was mixed with this mixture, and this mixture was poured into a container to foam-mold a rigid urethane heat insulating foam.

After 1 hour of foaming by pouring into the container, the gas in the bubbles of the heat insulating foam obtained was analyzed by gas chromatography. The chloroform extract was analyzed by liquid chromatography to measure the amount of carbon dioxide in the heat insulating foam. Further, the amount of isocyanate groups was determined from the measurement of the infrared absorption spectrum of the foamed heat insulating material fragment. As a result, the average molar concentration ratio was epoxide molar concentration / (carbon dioxide molar concentration + isocyanate group molar concentration) = 2.0. This ratio tended to increase even after January. The thermal conductivity decreased by 6.9% after 1 month, based on 1 hour after foaming.

Comparative Example 1 Foam molding was carried out in the same manner as in Example 1 except that the urethane catalyst tetramethylethylenediamine was used in the same parts by weight instead of the delayed activation type resinified catalyst composition of Example 1. The measured average concentration is epoxide concentration / (carbon dioxide concentration + isocyanate concentration) =
0.7. This ratio is on a downward trend after January,
The thermal conductivity was 0.
It decreased by 5%.

The reason why the heat insulating property of the foam of Example 1 is improved is considered as follows. That is, in Comparative Example 1, the amount of epoxide reacted with isocyanate was reduced, and the amount with respect to carbon dioxide was insufficient, whereas in Example 1, the delayed activation type resinification catalyst composition was used as a resinization catalyst. As a result, the amount of isocyanate after foam molding was reduced, the loss of epoxide was reduced, and a sufficient amount of epoxide with respect to carbon dioxide was secured.

Example 2 In this example, 5 wt% of dibutyltin dilaurate was added to pentaerythritol as a solid alcohol as a delayed activation type resin catalyst composition.
What was dispersed was used. In addition, N-methylmorpholine was used together as a weak urethane catalyst. This catalyst is also a kind of the delayed activation type resin catalyst composition. The weight ratio of the raw materials used is as follows. Polyol A / Foam stabilizer A / N
-Methylmorpholine / delayed activation type resin-forming catalyst composition / tetrabutylammonium iodide / phenyl glycidyl ether / cyclopentane / water / isocyanate-
G = 100/3/3/10/15/30/15/1/1
31. First, premix 1 was prepared by mixing polyol A, foam stabilizer A, N-methylmorpholine, tetrabutylammonium iodide, and phenylglycidyl ether. Further, cyclopentane was mixed with the delayed activation type resin-ized catalyst composition and dispersed by a homogenizer to prepare a premix 2. Immediately after producing the premix 2, the premixes 1 and 2 and further isocyanate were mixed and injected into the container to foam-mold the heat insulating foam.

One hour after the injection and foaming, the concentration was measured in the same manner as in Example 1. As a result, the average concentration ratio was epoxy molar concentration / (carbon dioxide molar concentration + isocyanate group molar concentration) = 3.0. This ratio remained almost unchanged after January. The thermal conductivity was decreased by 6.3% after 1 month, based on 1 hour after foaming.

Comparative Example 2 A heat insulating foam was formed in the same manner as in Example 2 except that 0.9 part by weight of dibutyltin dilaurate was used in place of the delayed activation type resinified catalyst composition of Example 2. did. However, dibutyltin dilaurate was mixed with all materials except isocyanate to form a premix, which was mixed and injected with isocyanate to form a heat insulating foam. However, the foaming was so fast that it was not injected into every corner of the container.

In Comparative Example 2, since the highly active catalyst worked from the beginning of the foaming process, the foaming became too fast and the container could not be filled successfully. On the other hand, in Example 2, since the catalytic activity of highly active dibutyltin dilaurate is expressed with a delay, the residual amount of isocyanate is reduced due to the completion of the filling property and the urethane reaction, thereby reducing the thermal conductivity. It is thought that it was done.

[Example 3] In this example, the delayed activation type resin material composition was thermally expanded using propyl alcohol as a core and polyvinylidene chloride copolymer (softening temperature 110 ° C) as a wall material. Sex microcapsules were used.
The weight ratio of the materials used for foaming is as follows. Polyol A / Foam stabilizer A / Zinc chloride / Delayed activated resin composition / Tetrabutylammonium bromide / Hexylene oxide / Cyclopentane / Water / Isocyanate =
100/3 / 0.2 / 6/11/11/17/15/14
0. A mixture was injected in the same manner as in Example 1 to produce a heat insulating foam. One hour after foaming, the concentration was measured in the same manner as in Example 1. As a result, the average concentration ratio was epoxide concentration / (carbon dioxide concentration + isocyanate group concentration) = 2.7. This ratio also tended to increase after January. The thermal conductivity decreased by 4.4% after 1 month, based on 1 hour after foaming.

Comparative Example 3 A heat insulating foam was formed in the same manner as in Example 3 except that isopropyl alcohol was used in place of the delayed activation type resinified catalyst material composition of Example 3. Measured average molar concentration ratio is epoxide molar concentration / (carbon dioxide molar concentration + isocyanate group molar concentration)
= 0.8, which decreased by 1.4% one month later.

In Comparative Example 3, since the highly reactive propyl alcohol was consumed in the initial stage of foaming and the polyol having the usual reactivity remained, the residual amount of the isocyanate remained almost unchanged. On the other hand, in Example 3, propyl alcohol having high reactivity is released in the latter stage of foaming, so that the amount of residual isocyanate is reduced, which is considered to reduce the thermal conductivity.

Example 4 In this example, an oxime block of m-phenylene diisocyanate was used as the delayed activation type resin material composition. Regarding the reaction rate with the polyol A in the presence of dibutyltin dilaurate, the m-phenylene diisocyanate was more than twice as fast as the isocyanate A compared with the gel time. The weight ratio of the materials used for foaming is as follows. Polyol A / Foam stabilizer A / Dibutyltin dilaurate / Delayed activated resin composition / Tetrabutylammonium bromide /
Phenylglycidyl ether / cyclopentane / water / isocyanate A = 100/3 / 0.2 / 20/11/2
5/15/1/115. A mixture was injected in the same manner as in Example 1 to produce a heat insulating foam. One hour after foaming, the concentration was measured in the same manner as in Example 1. As a result, the average concentration ratio was epoxide concentration / (carbon dioxide concentration + isocyanate group concentration) = 1.9. This ratio also tended to increase after January. The thermal conductivity decreased by 4.4% after 1 month, based on 1 hour after foaming.

[Comparative Example 4] A heat insulating foam was formed by using only the isocyanate A without using the delayed activation type resinified catalyst material composition of Example 4 and using the same other materials. The measured average concentration ratio was epoxide concentration / (carbon dioxide concentration + isocyanate group concentration) = 0.9, and no decrease was observed even after one month.

In Example 4, it is considered that since the highly reactive isocyanate was released in the latter stage of the foaming, the amount of the remaining isocyanate was reduced, and the thermal conductivity was reduced.

[0039]

INDUSTRIAL APPLICABILITY As described above, in the heat insulating foam of the present invention, the fixation of carbon dioxide proceeds efficiently, and the thermal conductivity greatly improves over time. Further, according to the production method of the present invention, the urethane reaction is completed, the amount of residual isocyanate after foaming is reduced, the side reaction between the isocyanate and the epoxide is suppressed, carbon dioxide is efficiently fixed, and It is possible to obtain a heat-insulating foam having a significantly improved thermal conductivity. In addition, the degree of completion of the urethane reaction is high, and a stronger heat insulating foam can be obtained.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takayoshi Ueno 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (7)

[Claims] 1. A foamed urethane resin composition comprising an epoxide and a carbonate component formed by reaction of the epoxide with carbon dioxide, wherein carbon dioxide, an isocyanate group in the urethane resin composition, And the average molar concentration of epoxy groups is epoxy group molar concentration> carbon dioxide molar concentration + isocyanate group molar concentration. 2. An epoxide or a card formed by reacting the epoxide with carbon dioxide generated after foaming.
A method for producing a heat insulating foam comprising a urethane foam resin composition containing a bone component, wherein at least one of the delayed activation type resinification catalyst composition and the delayed activation type resinification material composition is a raw material of urethane resin. By increasing the degree of progress of the urethane resin forming reaction by mixing with, by reducing the amount of isocyanate groups remaining immediately after the end of the resinification reaction, the fixation reaction of carbon dioxide by the epoxide is promoted. A method for producing a heat insulating foam. 3. The method for producing a heat insulating foam according to claim 2, wherein the delayed activation type resinification catalyst composition is used as a resinization catalyst, and an epoxide that vaporizes at the time of foaming at a boiling point of 70 ° C. or less is used as the epoxide. 4. The method for producing a heat insulating foam according to claim 3, wherein the epoxide is propylene oxide or 1,2-epoxybutane. 5. A powder or heat-expandable microcapsules containing, in addition to the urethane catalyst as the resin-forming catalyst, a catalyst that activates the resin-forming reaction more than the urethane catalyst,
The method for producing a heat insulating foam according to claim 2, wherein the method is used as the delayed activation resinification catalyst composition. 6. A delayed activation resin containing powder or heat-expandable microcapsules containing alcohol having a higher reactivity with the isocyanate component than the polyol in a raw material of the urethane resin containing a polyol and an isocyanate. The method for producing a heat insulating foam according to claim 2, which is used as a chemical composition. 7. A delayed activation resin containing a blocked isocyanate of an isocyanate having a higher reactivity with the polyol than the isocyanate in a raw material of the urethane resin containing a polyol and an isocyanate. The method for producing a heat insulating foam according to claim 2, which is used as a chemical composition.