JPH07206545A - High-thermal insulation molded form containing low thermally conductive polymer capsule - Google Patents

Abstract

PURPOSE:To obtain the subject molded form having advantageous properties of both inorganic and organic thermal insulation materials, excellent in thermal insulation, mechanical strength and flame resistance. CONSTITUTION:This high-thermal insulation molded form is composed of 100 pts.wt. of silica and/or calcium silicate crystal form and 5 300 pts.wt. of polymer capsules containing >=30vol.% of a gas <=0.02kcal/mh deg.C in thermal conductivity and having a particle diameter of <=500mum.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention overcomes the drawbacks of inorganic heat insulating materials such as low heat insulation, brittleness and cracking, and organic heat insulating materials such as melting and deformation when hit by a flame. High heat insulating molded article.

[0002]

2. Description of the Related Art Most of the heat insulation methods in detached houses
Although 10K type (density 10 kg / m ³ ) glass wool is used as a heat insulating material, its heat insulating performance is low (thermal conductivity λ =
(0.045 kcal / mh ℃), it is necessary to increase the thickness of the heat insulating material in order to save energy, which has the drawback of reducing the living space. In addition, inorganic heat insulating materials such as calcium silicate are also commercially available, but the thermal conductivity λ = 0.032 to 0.045
Insulation performance is improved at kcal / mh ℃ level. However, especially for materials with good heat insulation performance, the space ratio is made large and the specific gravity is made small in order to utilize the heat insulation of air, but inorganic materials have the drawback of being brittle and easily cracked, which makes the space unnecessarily vulnerable. There is a limit because the rate cannot be increased. On the other hand, in the organic type, foamed polyurethane, polystyrene, etc. are commercially available and have elasticity and high strength, so that they are excellent in workability and have excellent heat insulating performance, but on the other hand, they have a drawback that they are melted and deformed when exposed to a flame.

As a composite of an inorganic type and an organic type, a method of mixing organic foamed beads such as expanded polystyrene beads into cement or foamed cement has been proposed, but in order to improve heat insulation performance, organic foamed beads are used. Since a large amount of organic foam beads occupy most of the volume, the amount of cement that should serve as a binder is reduced, and it becomes an insulating material with extremely weak strength and no flame resistance. In general, it is only limited to a small amount of organic foam beads to improve the heat insulation performance of cement and foam cement to some extent.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a highly heat-insulating molded article having advantageous properties of both inorganic and organic heat insulating materials which are excellent in heat insulation, strength and flame resistance. To provide.

[0005]

The present invention has a thermal conductivity of 0. 0 with respect to 100 parts by weight of silica and / or calcium silicate crystals.
5 polymer capsules with a particle size of 500 μm or less that contain gas containing 30 vol% or more of 02 kcal / mh ° C or less
The present invention relates to a highly heat-insulating molded article, characterized in that it is contained in an amount of 300 parts by weight.

The present invention is a molded product obtained by aggregating a silicic acid and / or calcium silicate crystal and a polymer capsule, and high heat insulation performance can be obtained by enclosing a gas having a low thermal conductivity in the polymer capsule.

The thermal conductivity of the gas contained in the polymer capsule exceeds 0.02 kcal / mh ° C., and the thermal conductivity is 0.02 kcal / mh ° C.
When the gas content of kcal / mh ° C or less is less than 30 vol%, the thermal conductivity of air is equal to 0.0208 kcal / mh ° C, and a heat insulating material having a low thermal conductivity cannot be obtained.
The preferred thermal conductivity of the gas contained in the polymer capsule is 0.02 kcal / mh ° C or lower, and 0.012 to 0.0001 kc.
A range of al / mh ° C is preferred. The proportion of such gas in the gas in the polymer capsule is preferably 30 to 100 vol%, more preferably 60 to 100 vol%.

If the particle size of the polymer capsule exceeds 500 μm, the gas in the polymer capsule causes convection, which increases the thermal conductivity. Further, since the size is too large compared to the size of the silicic acid or calcium silicate crystals, if the addition amount exceeds 300 parts by weight, the connection between the calcium silicate crystals becomes rough and it cannot be made into a compact. If the amount added is less than 5 parts by weight, the effect of the low thermal conductivity gas contained in the polymer capsule is small and high heat insulation performance cannot be obtained. The particle size of the polymer capsule is preferably 5 to 500 μm, and particularly preferably 10 to 100 μm.

As a method for producing a polymer capsule having a particle diameter of 500 μm or less used in the present invention, a chemical method (interfacial polymerization method, in-liquid curing coating method, etc.), a physicochemical method (layer separation method, in-liquid drying method, melting method) Dispersion cooling method, inclusion exchange method, etc.), mechanical and physical methods (powder bed method, air suspension coating method, spray drying method, vacuum deposition coating method, electrostatic coalescence method, etc.), The method is not particularly limited as long as it meets the purpose of the present invention, but the following method applying the interfacial polymerization method is preferable.

That is, a volatile solution is dispersed in water in the form of particles of several tens of μm, a polymer is polymerized on the surface of the particles to form a polymer capsule precursor, and the polymer is softened above the boiling point of the volatile solution. The volatile solution is volatilized and expanded by heating above the point, and the polymer capsule is obtained by expanding the capsule. In the present invention, this volatile solution has a thermal conductivity of 0.02 kcal /
Select one that is below mh ° C. Thermal conductivity is 0.02kcal /
Examples of gases at mh ° C and below include inorganic substances such as carbon dioxide and water vapor, low molecular weight aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane and octane, petroleum ether, methylsilane, alternative CFCs and perfluorocarbons. Aliphatic hydrocarbons and the like can be mentioned. Dichlorotrifluoroethane (HCFC-123), dichlorofluoroethane (HCFC 141b), difluoroethane (HFC-152a), tetrafluoroethane (HF)
C134a) and the like are C ₅ F ₁₂ (PF-5050 manufactured by Sumitomo 3M Limited) as a perfluoroaliphatic hydrocarbon,
C ₆ F ₁₄ (manufactured by Sumitomo 3M Co., Ltd., PF-5060),
C ₇ F ₁₆ (PF-5070 manufactured by Sumitomo 3M Limited) and the like can be mentioned.

On the other hand, as the material of the capsule of the polymer capsule, a polymer having a small gas permeability is preferable so that the enclosed gas does not vaporize through the capsule membrane. For example, polyvinylidene chloride, polyacrylonitrile, polyvinyl alcohol, polyimide and the like are preferable.

In the present invention, as the silicic acid, fine powder silica having an average particle diameter of 1 μm or less, which is produced by a vapor phase method, is preferably used. When the average particle size is 1 μm or less as shown in JP-A-5-194058, the average particle size is 500 μm.
This is because a molded product having low specific gravity and high strength can be easily obtained by adding water to the following synthetic resin foam (polymer capsule) and mixing them in a slurry state, and then removing water by drying. The average particle size of silicic acid is preferably 0.007 to 1 μm, and particularly preferably 0.01 to 0.05 μm.

On the other hand, the calcium silicate crystal used in the present invention is synthesized by hydrothermally reacting a dispersion of silicic acid and lime in water. Needle-shaped xonotlite crystals are synthesized by setting the hydrothermal reaction conditions to 180 ° C or higher and 10 atm or higher, and by further stirring during the hydrothermal reaction, zonotolite crystal aggregates can be obtained. Such is preferable.

The molded product of the present invention is obtained, for example, by mixing a slurry of calcium silicate crystal synthesized by hydrothermal reaction with a polymer capsule, dehydrating and molding, and then drying. When mixing silicic acid or calcium silicate slurry with polymer capsules, it is possible to add fiber materials such as glass fiber, carbon fiber, vinylon fiber and rock wool, or to add granular fillers such as calcium carbonate, silica sand and clay. it can. Further, an aggregating agent, a polymer emulsion, a surfactant or the like can be added. Further, it is possible to modify the surface by adhering paper, a metal plate, a gypsum board or the like to the surface of the highly heat insulating molded product with an adhesive, or by applying an inorganic or organic paint.

In the highly heat-insulating molded article of the present invention, the polymer capsules are linked by being surrounded by a silicic acid or calcium silicate crystal. Therefore, even if the polymer capsule burns due to, for example, a fire, the shape of the molded body can be maintained only with the silicic acid or calcium silicate crystal, and it has a highly safe performance as a building material for houses. Is.

[0016]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples. Only parts and% refer to parts by weight and% by weight, respectively.

A. Calcium silicate crystal slurry (CS
-1) Preparation of silicic acid (white carbon) 77.5 parts, slaked lime 97.5 parts water
After adding 3500 parts and stirring and mixing, the mixture was placed in an autoclave and hydrothermally reacted at 200 ° C. and 15 atm for 5 hours with stirring at 200 rpm to agglomerate to a particle size of 30 μm, with a solid content of 5%. A slurry of zonotolite crystals was obtained. B. Silicic Acid Slurry (SA-1) As the silicic acid prepared by the vapor phase method, a slurry having a solid content of 10% was used, in which 900 parts of water was added to 100 parts of AEROSIL 200 (Japan Aerosil, average particle diameter 0.012 μm). C. Preparation of polymer capsule (PC-1) Cyclopentane (thermal conductivity 0.0095kcal / mh ℃) in water
The particles were dispersed in a particle size of 50 μm, and polyvinylidene chloride was polymerized on the surface of the particles, and then water was removed to obtain a powdery polymer capsule precursor. The polymer capsule precursor was heated and expanded under saturated steam at 100 ° C. to obtain a polymer capsule having an average particle diameter of 40 μm and a bulk specific gravity of 0.02. The proportion of gaseous cyclopentane contained in this polymer capsule was 90 vol%.

Examples 1 to 4 The polymer capsule (PC-1) prepared in C was added to the slurry (CS-1) prepared in A and mixed well,
It was put in a 120φ mold, dehydrated and molded at a pressure of 0.6 kg / cm ² , then left in an oven at 100 ° C for 10 hours and dried to obtain a molded body. The results are shown in Table 1.

Examples 5 to 7 The polymer capsule (PC-1) prepared in C was added to the slurry (SA-1) prepared in B and mixed well.
It was put in a 120φ mold and left to dry at 40 ° C. for 24 hours and 105 ° C. for 24 hours to obtain a molded body. The results are shown in Table 1.

Examples 8 to 9 Instead of cyclopentane, n-pentane (heat conductivity 0.011
kcal / mh ° C.), except that the above-mentioned C was used, a polymer capsule containing 50 vol% of n-pentane and having an average particle size of 20 μm (PC-2, Example 8) and a polymer capsule of 60 μm (PC-3, Example 9) was obtained. A molded body was obtained in the same manner as in Example 5 or Example 1 except that this polymer capsule was used. The results are shown in Table 2.

Examples 10 to 11 Perfluoroaliphatic hydrocarbon was added in the same manner as in the above C except that PF-5050 (C ₅ F ₁₂ , thermal conductivity 0.000414 kcal / mh ° C.) was used in place of cyclopentane. % To obtain a polymer capsule (PC-4) having an average particle diameter of 120 μm. A molded body was obtained in the same manner as in Example 5 or Example 1 except that this polymer capsule was used. The results are shown in Table 2.
Shown in.

Comparative Examples 1 and 2 Comparative molded bodies were obtained in the same manner as in Example 1 except that the compounding ingredients shown in Table 3 were used. The results are shown in Table 3.

Comparative Examples 3 to 4 Instead of the polymer capsule, a fine particle silas balloon (SB
-1, Comparative Example 3) or expanded styrene beads (ST-1,
A comparative molded body was obtained in the same manner as in Example 5 except that Comparative Example 4) was used. The results are shown in Table 3. In the table, () indicates solid content. SB-1: Shirasu balloon manufactured by Calceed Co., Ltd. having an average particle diameter of 15 μm, and air (heat conductivity of 0.0208 kca) is contained in the balloon.
l / mh ° C) is contained. ST-1: Sekisui Chemical Co., Ltd., styrene bead foam with an average particle size of 1.2 mm, Dairac beads 1240

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

In general, it is extremely difficult to make the thermal conductivity of an inorganic molded product having air as a heat insulator smaller than 0.030 kcal / mh ° C. But from the table, according to the invention,
It is clear that the wall with this thermal conductivity of 0.030 kcal / mh ℃ can be broken through significantly.

[0028]

According to the present invention, the thermal conductivity can be 0.030 kcal / mh ° C or less despite the use of an inorganic material, and when a flame such as a fire hits the material, The contained polymer capsules burn temporarily, but thereafter, silicic acid or calcium silicate crystals remain, and the excellent effect of withstanding a temperature of 800 ° C. or higher is maintained without destroying the shape of the molded body. Thus, the molded product of the present invention has highly safe performance as a heat insulating material for a house.

Claims (4)

[Claims] 1. Silica and / or calcium silicate crystals 1
With respect to 00 parts by weight, a particle size of 500μ containing a gas containing 30vol% or more of a gas with a thermal conductivity of 0.02kcal / mh ° C or less is 500μ.
A highly heat-insulating molded article, which comprises 5 to 300 parts by weight of a polymer capsule having a size of m or less. 2. The average particle size of silicic acid produced by the vapor phase method is 1 μm.
The highly heat insulating molded article according to claim 1, which is the following fine powder silica. 3. The highly heat-insulating molded article according to claim 1, wherein the calcium silicate crystal is a needle-shaped zonotolite crystal or an aggregate of this zonotlite crystal. 4. The highly heat-insulating molded article according to claim 1, wherein the gas having a thermal conductivity of 0.02 kcal / mh ° C. or less is cyclopentane or n-pentane or a perfluoroaliphatic hydrocarbon having a boiling point of 120 ° C. or less.