JPH05247249A - Blowing agent and production of plastic foam - Google Patents

Abstract

PURPOSE:To obtain the title agent which can give a foam excellent in heat insulation properties and mechanical strengths, does not have a risk of depleting the ozonosphere, is noncombustible and is excellent in the compatibility with materials for a foam by using a specified compound. CONSTITUTION:The title agent comprises at least one member selected between 1,1,1,2,3,4,4,5,5,5-decafluoro-2-pentene and 1,1,1,2,3,4,4,5,5,5-decafluoropentane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plastic foam,
In particular, it relates to a foaming agent for the production of isocyanate-based foams, preferably polyurethane foams, and a process for the production of plastic foams using this foaming agent.

In this specification, "%" and "part" mean "wt%" and "part by weight", respectively.

[0003]

Conventionally, trichlorofluoromethane (CFC-11) has been mainly used as a foaming agent for producing plastic foams such as polyurethane foam.

However, in recent years, when released into the atmosphere, some CFCs destroy the ozone layer in the stratosphere,
As a result, it has been pointed out that it has a serious adverse effect on the earth's ecosystem including humankind. Therefore, the use and production of CFCs, which have a high risk of depletion of the ozone layer, have been limited by international agreements. The above CFC-11 is subject to this restriction, and from this point as well, it is necessary to develop a new foaming agent that has no or low risk of causing an ozone depletion problem.

1,1-dichloro-2,2,2-trifluoroethane (HCFC-123) and 1,1-dichloro-1-fluoroethane (HCFC-141b) are proposed as CFCs having a small influence on the ozone layer. However, since they contain chlorine atoms in their molecules, there is still a risk of depleting the ozone layer.

Recently, as a foaming agent using a fluorinated hydrocarbon containing no chlorine atom and having no risk of destroying the ozone layer, (1) JP-A-2-29440 discloses CF ₃ CH ₂ CH ₂
The CF _3, (2) Japanese Patent Laid-Open No. 2-235982 is, CF ₃ CH (CH ₃₎ as a HFC having 3 to 5 carbon atoms CF _3, C
F ₃ CH ₂ CF ₃ and CH ₃ CF ₂ CH ₂ CHF
_2, (3) JP-A-2-265933, the the HFC having 3 carbon atoms, and (4) JP-A-3-746, C ₄ F ₉
H and H (CF ₂ ) ₄ H are proposed respectively.

Although these foaming agents do not have a risk of depleting the ozone layer, they are flammable and may cause a fire.
Since it has poor solubility in polyols, the usable polyols are limited, or the obtained foam has insufficient heat insulating performance, mechanical strength, and the like, there is still room for improvement.

[0008]

DISCLOSURE OF THE INVENTION The present invention has no risk of destroying the ozone layer, is nonflammable, has excellent compatibility with the foam raw material, and has excellent heat insulation properties for the foam obtained.
The main object of the present invention is to provide a foaming agent for producing a plastic foam which can impart mechanical strength and the like, and a method for producing a plastic foam using the foaming agent.

[0009]

As a result of repeated studies in view of the above problems in the prior art, the present inventor has found that
1,1,1,2,3,4,4,5,5,5-decafluoro-2-pentene and 1,1,1,2,3,4,4
It has been found that the above object can be achieved by using at least one kind of 5,5,5-decafluoropentane as a foaming agent.

That is, the present invention is 1, 1, 1, 2, 3,
Production of a plastic foam comprising at least one of 4,4,5,5,5-decafluoro-2-pentene and 1,1,1,2,3,4,5,5,5-decafluoropentane The present invention provides a foaming agent.

The present invention also provides a foaming agent with 1,1,
1,2,3,4,4,5,5,5-decafluoro-2-
Penten and 1,1,1,2,3,4,4,5,5,5
It is intended to provide a method for producing a plastic foam characterized by using at least one kind of 5-decafluoropentane.

In the following, 1, 1, 1, 2, 3,
4,4,5,5,5-decafluoro-2-pentene is referred to as Compound A, and 1,1,1,2,3,4,5,5,5
5-decafluoropentane is referred to as Compound B.

The compound A used in the present invention is a known compound, and its production method is also described in the literature (for example, Bull. Acad. Sci. USSR Di.
v. Chem. Sci. , 24 (1975), 2164
reference).

The compound B can be produced by hydrogenating the compound A. Therefore, the compound A may be mixed in the compound B.

Table 1 shows the main physical properties of the compounds A and B used in the present invention.

Table 1 Compound A Compound B Molecular formula CF ₃ CF ₂ CF = CFCF ₃ CF ₃ CF ₂ CHFCHFCF ₃ Molecular weight 250 252 Boiling point 25 ° C. 55 ° C. Ozone depletion potential 0 0 The blowing agent of the present invention is used alone. Or it may be used in combination with other foaming agent or water. Other blowing agents that can be used in combination include, for example, CFC-11, CFC-12, and other low-boiling halogenated hydrocarbons; i-pentane,
Low boiling point hydrocarbons such as n-pentane, cyclopentane, n-hexane and cyclohexane; inert gases and the like can be mentioned.

Since these combined substances have a boiling point of about 20 to 110 ° C. and form an azeotropic or azeotrope-like composition with the foaming agent of the present invention, a more uniform foam can be obtained. preferable. For example, compound A and cyclopentane, n-hexane, and cyclohexane having a boiling point of 20 to 90 ° C. form an azeotropic or azeotrope-like mixture in the following composition range, and therefore it is preferably used within this composition range. .

Compound A / cyclopentane = 75-85 /
25-15 (%; the same applies below) Compound A / n-hexane = 90-97 / 10-3 Compound A / cyclohexane = 85-95 / 15-5 Also, compound B and cyclohexane having a boiling point of 45-110 ° C, n- Since heptane, i-octane and the like form an azeotropic or azeotrope-like mixture in the following composition range, it is preferably used within this composition range.

Compound B / cyclohexane = 75-85 /
25-15 (%; the same applies hereinafter) Compound B / n-heptane = 90-97 / 10-3 Compound B / i-octane = 90-97 / 10-3 Stabilization of the foaming agent of the present invention, if necessary. Agents can be added. Examples of such stabilizers include the following.

* Alkenyl group-containing compound having at least one double bond: 1,4-hexadiene, allene,
1,3-butadiene, isoprene, 1,3-pentadiene, β-myrcene, isopropenyltoluene, butadiene, aroocimene,

[0021]

[Chemical 1]

* Epoxy group-containing compounds; for example, ethylene glycol diglycidyl ether, hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, trimethylpropane triglycidyl ether, glycerin polyglycidyl ether, glycid- (2-nitro- Phenyl ether), glycid-
(2-nitro-4-chloro-phenyl ether), glycid- (4-vinyl-phenyl ether), glycid-
(4-isopropenyl-phenyl ether), 1,3-
Butadienyl glycidyl ether, 3-methyl-1,3
-Butadienyl glycidyl ether, 3-vinyl-1,
3-Butadienyl glycidyl ether, benzoic acid glycidyl ester, acrylic acid glycidyl ester, furancarboxylic acid glycidyl ester, N, N-diglycidyl aniline, glycidyl phenyl ether, glycidyl-
p-isopropenyl phenyl ether, glycidyl-p
-Nitrophenyl ether and the like.

* Acrylic acid esters and methacrylic acid esters; for example, 2-hydroxyethyl methacrylate, diethylene glycol monoethyl methacrylate, methoxy polyethylene glycol monoethyl methacrylate and the like.

* Polyalkoxylated methacrylates;
For example, polyethylene glycol monoethyl methacrylate, polypropylene glycol monoethyl methacrylate, etc.

* Phenols; for example, 2,6-di-t
-Butyl-p-cresol, thymol, pt-butylphenol, eugenol, isoeugenol, butylhydroxyanisole, t-butylcatechol, 2,5
-Di-t-butyl hydroquinone and the like.

* Cyclic alkylene carbonates such as propylene carbonate, 1,2-butylene carbonate, styrene carbonate, vinyl ethylene carbonate and phenyl ethylene carbonate.

* Nitro compounds; for example, nitromethane, nitroethane, nitropropane, nitrobenzene and the like.

* Benzophenones; for example, t-butylchlorobenzophenone, isoamylbenzophenone and the like.

* Benzotriazoles: hydroxyphenylbenzotriazole, hydroxymethylphenylbenzotriazole, 2- (3 ', 5'-di-t-butyl-2'-hydroxyphenyl) benzotriazole and the like.

* Phenylsalicylates; for example, phenylsalicylate, p-octylphenylsalicylate and the like.

These stabilizers may be used alone or in combination of two or more. The amount of these stabilizers used may vary depending on the type of the stabilizer itself, the composition of the foaming component, etc., but usually about 0.05 to 5% by weight of the foaming component is suitable, and 0.2 to 1. It is more preferable to set it to about 0%. If the amount of the stabilizer is too small, the reaction between the polyol and the foam material cannot be effectively prevented. On the other hand, even if the amount used exceeds 5%, substantial improvement in the stabilizing effect cannot be expected.

The foaming agent of the present invention can be used in the same manner as a known foaming agent for producing a plastic foam.

Examples of the plastic foam produced by using the foaming agent of the present invention include isocyanate, polyethylene, polystyrene, polyvinyl chloride, phenol /
Examples of the foam include a formaldehyde condensate as a raw material. The foam material according to the present invention is suitable for producing a foam made of isocyanate as a raw material, and particularly suitable for producing a polyurethane foam and a polyisocyanurate foam.

The amount of the foaming agent of the present invention used with respect to the plastic as the foaming raw material is the same as that of the known foaming agent. The amount used is appropriately determined depending on the type of foaming raw material, the density of the desired foam, etc., but is usually 1 to 40% as a ratio of the foaming agent to the total of the foaming raw material and the foaming agent.
Degree, preferably about 2 to 20%.

The production of a foam using the foaming agent of the present invention may be carried out in the same manner as a known method. For example, when producing a polyurethane foam, an active hydrogen compound having two or more active hydrogen-containing groups such as a polyol and a polyisocyanate compound may be reacted in the presence of a catalyst and a foaming agent according to a conventional method. More specifically, a desired plastic foam can be produced by a known one-step method, prepolymer method, block foaming method, double belt conveyor method, or the like.

In the method for producing a plastic foam according to the present invention, known additives such as a foam stabilizer and a catalyst may be used. Examples of the foam stabilizer include a silicone-based foam stabilizer and a fluorine-containing foam stabilizer, which are used in an amount of about 0.1 to 2% based on the foaming raw material. Examples of the catalyst include tertiary amine catalysts such as triethylenediamine and metal compound catalysts such as organic tin compounds, which are used in an amount of about 0.1 to 5% based on the foaming raw material.

In addition to the foaming agent of the present invention, water, a filler, a coloring agent, a flame retardant and the like can be added, if necessary.

[0038]

According to the present invention, the following effects are achieved.

(1) Compounds A and B used in the present invention
Has an ozone depletion coefficient of 0, and there is no danger of depleting the ozone layer.

(2) Since the foaming agent of the present invention is nonflammable and has low toxicity, it is safe in operation.

(3) Since the foaming agent of the present invention has good compatibility with the polyol, it is extremely suitable for producing a urethane foam.

(4) The foaming agent of the present invention has good storage stability.

(5) Since the plastic foam obtained using the foaming agent of the present invention is composed of closed cells, it has excellent heat insulating properties, dimensional stability, compressive strength, appearance and uniformity.

[0044]

EXAMPLES Examples and comparative examples will be shown below to further clarify the features of the present invention.

[0045]

Example 1 Compatibility Test with Polyol The stability of a mixture of the foaming agent of the present invention and a polyol, that is, a premix was examined by the following method.

A total of 30 g of the foaming agent of the present invention and polyol A, B or C (foaming agent content 30%) was placed in a glass bottle with a screw cap having a capacity of 50 ml, and the mixture was shaken with a shaker for 10 minutes and then at room temperature. After leaving still for 5 hours, the presence or absence of separation was visually confirmed.

The following polyols A, B and C were used.

Polyol A: Polyether polyol having a hydroxyl value of 770 obtained by reacting ethylenediamine with propylene oxide Polyol B: Polyether polyol having a hydroxyl value of 470 obtained by reacting sucrose and ethylenediamine with propylene oxide Polyol C: Sucrose added to propylene oxide Table 2 shows the results for each of the foaming agents having a hydroxyl value of 430.

In Table 2, compatibility was evaluated according to the following criteria.

O: No phase separation.

Δ: There is some phase separation, but there is no problem in use.

Table 2 Polyol foaming agent (A) (b) (c) (d) A △ ○ B ○ ○ ○ ○ C △ ○ ○ ○ Note: Foaming agent (a); Compound A Foaming agent (b); Compound A / i-pentane = 90 / Ten(%;
The same shall apply hereinafter) Foaming agent (c); Compound B Foaming agent (d); Compound B / cyclohexane = 80/20 From the results shown in Table 2, the foaming agent of the present invention is the same as the polyol at the mixing ratio actually used. It was confirmed that it showed good compatibility and formed a stable premix.

[0053]

Example 2 Production of Foam (1) Production of Foam Using Polyol B 100 g of Polyol B, 2 g of silicone type foam stabilizer, 2 g of water, N, N, N ′, N′-tetra as a catalyst 2 g of methylhexane-1,6-diamine and (e) compound A / i-pentane as blowing agent according to the invention = 90/10
20 g of the mixture of
Stir vigorously. This stirred mixture and 148 g of crude polymethylene polyphenyl isocyanate were mixed and foamed to obtain a rigid polyurethane foam.

The physical data of the foam and of the foam are shown in Table 3-A below.

[0055]Table 3-A Physical properties Foaming agent (e) Foaming agent (f) Cream time (sec) 8 15 Gel time (sec) 65 75 Free total density (kg / m³) 35 35 Compressive strength (kg / cm²) 1.35 1.40 Dimensional stability (-20 ° C, 24 hours (Δ%)) -0.3 -0.5Thermal conductivity (kcal / m · hr · ° C) 0.0185 0.0180 ( 2) Production of foam using Polyol C 100 g of Polyol C, 2 g of silicone type foam stabilizer, water
0.2 g, diethyl ethanolamine as catalyst 1.
5 g, dibutyltin dilaurate 0.15 g and the present invention
(To) compound A / i-pentane = 90 /
10 mixtures or (h) compound B / cyclohexane =
20 g of 80/20 mixture was mixed and stirred vigorously.
96 g of this stirred mixture and crude tolylene diisocyanate
Was mixed and foamed to obtain a rigid polyurethane foam.

Physical data for the resulting foam are shown in Table 3-B below.

Table 3-B Physical Properties Foaming Agent ( G ) Foaming Agent ( H ) Density (kg / m ³ ) 38 35 Compressive Strength (kg / cm ² ) Parallel 2.95 3.00 Vertical 1.051 .05 Dimensional stability (Δ%) 110 ° C., 7 days +1.6 +2.0 70 ° C., 95% RH, 7 days +7.4 +8.5 −20 ° C., 7 days −0.3 −0.5 The foaming agent of the present invention was evaluated according to the method specified in JIS A 9514.

From the results shown in Tables 3-A and 3-B, by using the foaming agent of the present invention, the heat insulating property,
It was confirmed that a plastic foam excellent in compressive strength and dimensional stability was obtained.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical indication location C08L 75:04 (72) Inventor Satoshi Ide 1-1 Nishiichitsuya, Settsu City, Osaka Prefecture Daikin Industries, Ltd. Yodogawa Works (72) Inventor Tatsumi Tachimi 1-1 Nishi-Itsuya, Settsu-shi, Osaka Daikin Industries, Ltd. Yodogawa Works (72) Inventor Katsuji Fujiwara Nishiichitsuya 1-1, Settsu-shi, Osaka Daikin Industries, Ltd. Yodogawa Manufacturing Co., Ltd. Within

Claims (8)

[Claims] 1. 1, 1, 1, 2, 3, 4, 4, 5, 5,
5-decafluoro-2-pentene and 1,1,1,
A foaming agent for producing a plastic foam, which comprises at least one of 2,3,4,4,5,5,5-decafluoropentane. 2. 1, 1, 1, 2, 3, 4, 4, 5, 5,
5-decafluoro-2-pentene and 1,1,1,
A foaming agent for producing a plastic foam, which comprises a mixture of at least one of 2,3,4,4,5,5,5-decafluoropentane and at least one of hydrocarbons. 3. The foaming agent according to claim 2, wherein the boiling point of the hydrocarbon is 20 to 110 ° C. 4. 1, 1, 1, 2, 3, 4, 4, 5, 5,
The foaming agent according to claim 3, comprising a mixture of 5-decafluoro-2-pentene and a hydrocarbon having a boiling point of 20 to 90 ° C. 5. The blowing agent according to claim 4, wherein the mixture is an azeotropic or azeotrope-like mixture. 6. 1, 1, 1, 2, 3, 4, 4, 5, 5,
The foaming agent according to claim 3, which comprises a mixture of 5-decafluoropentane and a hydrocarbon having a boiling point of 45 to 110 ° C. 7. The blowing agent according to claim 6, wherein the mixture is an azeotropic or azeotrope-like mixture. 8. A method for producing a plastic foam, which comprises using the foaming agent according to any one of claims 1 to 7.