JP3520110B2 - Flexible polyurethane foam and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible polyurethane foam in mold foaming and a method for producing the same. More specifically, as the organosilicon compound, in addition to the siloxane-oxyalkylene copolymer as the foam stabilizer component,
By using a specific low molecular weight polydiorganosiloxane, even when using only water without using halocarbons as a foaming agent, the range of mold temperature can be widened, and a flexible polyurethane foam having good properties can be obtained. The present invention relates to a manufacturing method that can be manufactured.

[0002]

2. Description of the Related Art Flexible polyurethane foams are widely used in various applications such as automobile seats and cushioning materials for furniture. In the production of flexible polyurethane foams, halocarbons such as chlorofluorocarbons are generally used as a foaming agent for the purpose of improving the physical properties of the foam. However, in recent years, the use of halocarbons has been restricted or abolished because of the possibility of causing ozone layer destruction.

[0003]

Therefore, the establishment of a production method that does not use halocarbons is urgently required. However, when only water is used as a blowing agent, the reaction heat is higher than when halocarbons are used. Comes out a lot. Moreover, since halocarbons have a large effect of absorbing reaction heat, the temperature in the system tends to be unstable unless they are used. For these reasons, in producing a flexible polyurethane foam without using halocarbons, there is a problem that the mold temperature is likely to change and many defective products can be produced.

[0004]

[Means for Solving the Problem and Its Action] As a result of intensive studies on the above problems, the present inventors have found that the use of a specific low molecular weight polydiorganosiloxane
The present invention has been achieved based on the finding that a flexible polyurethane foam can be produced by high temperature curing mold foaming even if the mold temperature is set wider than before.

Therefore, the present invention uses a polyol component, an isocyanate compound, water, a catalyst, a foam stabilizer and an additive to produce a polyurethane foam by high temperature curing mold foaming. In addition to the siloxane-oxyalkylene copolymer, etc., by using a specific low molecular weight polydiorganosiloxane, even when using only water without using halocarbons as a foaming agent, the mold temperature range And a flexible polyurethane foam having good properties can be produced. That is, the present invention is a polyol component and an isocyanate compound, water,
When a polyurethane foam is produced by high temperature curing mold foaming using a catalyst, a foam stabilizer and an additive, the general formula (1)

[Chemical 2] (Wherein, R is the same or different organic groups having 1 to 6 carbon atoms, and m is an integer of 3 to 7), and the low molecular weight polydiorganosiloxane of the cyclic polydiorganosiloxane is represented by 100 parts by weight of the polyol component. 0.02 to part
A method for producing a flexible polyurethane foam obtained by high temperature curing mold foaming, characterized in that 1.0 part by weight is contained.

In the present invention, the well-known polyols for flexible polyurethane foam used in the prior art can be used. A particularly preferred polyol is a polyether polyol obtained by adding alkylene oxides to an initiator, and particularly, has a functional group number of 2.5 to 3.5, a number average molecular weight of 2,000 to 8,000, and a hydroxyl group of 30. % Or more is a primary polyether polyol. Typical initiators include, but are not limited to, glycols such as ethylene glycol and propylene glycol, triols such as glycerin and trimethylolpropane, and the like. In the present invention, two or more kinds of these polyol components can be used at the same time.

There is no particular limitation on the type of the siloxane-oxyalkylene copolymer used as the foam stabilizer in the present invention, and any known siloxane useful for the production of the flexible polyurethane foam used in the prior art can be used. Oxyalkylene copolymers can also be used. For example, the general formula (3) or (4)

[Chemical 3]

[Chemical 4] (In the formula, R ^{1 to} R ⁸ are the same or different and represent an alkyl group having 1 to 8 carbon atoms, a hydrogen atom or a phenyl group,
a1, a2, a3, b1, b2 and b3 are 0 to an average number.
The average number of 30, ml is 0 to 600, and the average number of n1 and n2 is 1 to 20. Further, p1 and p2 are integers of 1 to 18, and i is 0 or 1. The polydialkyl siloxane-polyoxyalkylene copolymer represented by any of the above () can be used. These compounds are usually used in an amount of 0.4 to 3.0 parts by weight based on 100 parts by weight of the polyol component.

The low molecular weight polydiorganosiloxane used in the present invention includes cyclic or linear polydiorganosiloxane. The cyclic polydiorganosiloxane is represented by the above formula (1). In the formula, m is 3 to 7. The linear polydiorganosiloxane is represented by the above formula (2). In the formula, n is 0 to 9. Formulas (1) and (2) above
R therein is a monovalent organic group, and examples thereof include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group, a phenyl group and the like, and a methyl group is preferable.
R can be the same or different. Two or more kinds of these low molecular weight organic polydiorganosiloxanes may be mixed and used in the present invention. Linear polydiorganosiloxanes are usually supplied as products of specific viscosity, they are a mixture of polydiorganosiloxanes of multiple molecular weights. In that case, it may contain a high molecular weight component, and may have a bad influence on foam formation. For these reasons, the use of cyclic low molecular weight polydiorganosiloxane is preferred.

The amount of the low molecular weight polydiorganosiloxane used in the present invention is 0.02 to 1.0 part by weight based on 100 parts by weight of the polyol component. The reason is,
If it is less than this range, the effect of improving the mold temperature range is insufficient, and if it is more than this range, the surface moldability of the resulting polyurethane foam is deteriorated, which is not preferable.

The low molecular weight polydiorganosiloxane used in the present invention contains a polyol component, water, a foam stabilizer,
The catalyst and the additives may be mixed at the same time, or may be mixed in advance with other components such as a polyol component and a foam stabilizer component before use.

There are no particular restrictions on the type and amount of the isocyanate compound used in the present invention, and any known isocyanate compound for flexible polyurethane foam used in the prior art or a mixture of two or more isocyanate compounds can be used. You can use an appropriate amount. As a concrete example,
Examples thereof include toluene diisocyanate, 4,4′-diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate and the like, and derivatives thereof.

There is no particular limitation on the type and amount of the catalyst used in the present invention, and any known catalyst useful for the production of the flexible polyurethane foam used in the prior art can be used. As typical catalysts, tertiary amines and organometallic compounds are used, and they are usually used in combination. Specifically, as tertiary amines, bis (2,2′-dimethylamino) ethyl ether, trimethylamine, triethylamine, N-methylmorpholine, N-ethylmorpholine,
N, N-dimethylbenzylamine, N, N-dimethylethanolamine, N, N, N ', N'-tetramethyl-
1,3-butanediamine, triethanolamine, 1,
4-diazabicyclo- [2,2,2] octane, hexamethylenetetramine, pyridine oxide and the like are used. Further, the organic metal compound is effectively an organic derivative of tin,
For example, dibutyltin dilaurate, dibutyltin malate,
Examples thereof include dilauryl tin diacetate and dioctyl tin diacetate.

In the production of the flexible polyurethane foam of the present invention, an additive such as a colorant, an antioxidant, an ultraviolet absorber, a light stabilizer, a flame retardant and a filler which is usually used is added in an appropriate amount, if necessary. Is also good.

The present invention will be described below based on examples.
However, the present invention is not limited to this, and the technique of the present invention
All the embodiments utilizing the technical idea are included in the scope of the present invention.
It is what is done. In addition, it is used in Examples and Comparative Examples.
The meanings of the abbreviations are as follows.Polyol 1 Glycerin with propylene oxide and ethylene oxide
Addition polymerization of amide to make 70% of hydroxyl groups primary
Polyether polyol with an average molecular weight of 2,600Polyol 2 Glycerin with propylene oxide and ethylene oxide
Is added to the polymer to make 60% of the hydroxyl groups primary.
Polyether polyol with an average molecular weight of 3,000VS-7207 Octamethylcyclotetrasiloxane (Unicar Japan Co., Ltd.
Made)VS-7158 Decamethylcyclopentasiloxane (Unicar Japan Co., Ltd.
Made)L-45 (2) Linear dimethylpolycarbonate having a viscosity of 2 cSt at 25 ° C
LOXAN (made by Nippon Unicar)Dabco 33LV 33 of triethylenediamine and dipropylene glycol
/ 67 ratio mixture (manufactured by Sankyo Air Products)NIAX A-1 Amine-based catalyst (made by Union Carbide)Silicone foam stabilizer 1 Formula (5)

[Chemical 5] Silicone type foam stabilizer represented bySilicone foam stabilizer 2 Formula (6)

[Chemical 6] Silicone type foam stabilizer represented byTDI-80 80% by weight of 2,4-tolylene diisocyanate and 2,6
A mixture of 20% by weight of tolylene diisocyanate (Japan
(Made by Polyurethane Industry Co., Ltd.)

Examples 1 to 4 200.0 parts by weight of Polyol 1 with VS-7207 in an amount of 0.
Add 2 parts by weight and mix well. To this, 8.0 parts by weight of water, 1.5 parts by weight of silicone foam stabilizer 1, 33 L of Dubco
V was added at 0.44 parts by weight, NIAX A-1 at 0.22 parts by weight, and tin octylate at 0.26 parts by weight, and mixed at high speed. Immediately thereafter, TDI-80 (NCO / OH index 98) was added, the mixture was further stirred at high speed, and placed in a 40 × 40 × 10 cm box adjusted to the temperature shown in Table 1. After the foaming was completed, it was placed in a curing oven and cured. The physical properties of the obtained polyurethane foam were measured and shown in Table 1 together with the foam state. As shown in Table 1, 30
In the mold temperature range of -60 ° C, a polyurethane foam having a good foam state and good physical properties was obtained.

Comparative Examples 1 to 4 Polyurethane foams were prepared in the same manner as in Examples 1 to 4 except that VS-7207 was not added and the amount of water was 8.2 parts by weight. The physical property values were measured and shown in Table 1 together with the foam state. As shown in Table 1, VS-72
In the comparative example in which 07 was not used, defective foam state was observed at mold temperatures other than 40 ° C.

[0017]

[Table 1]

Examples 5 to 8 Polyurethane foams were prepared in the same manner as in Example 1 except that VS-7158 was added instead of VS-7207. When the physical property values were measured, as shown in Table 2, in the mold temperature range of 30 to 60 ° C., good foam state and characteristics were obtained.

[0019]Examples 9 to 12 (reference examples) Since L-45 (2) is added instead of VS-7207
Outside, polyurethane foam was prepared in the same manner as in Example 1.
Created. The physical properties were measured and as shown in Table 2.
Excellent foam shape in the mold temperature range of 30 to 60 ° C
It was a state and a characteristic.

[0020]

[Table 2]

Examples 13 to 16 Mixture A was prepared by thoroughly mixing 1.5 parts by weight of silicone foam stabilizer 2 and 0.2 parts by weight of VS-7207. To 200.0 parts by weight of Polyol 2, 8.0 parts by weight of water, 1.7 parts by weight of mixture A, 0.4 parts of Dubco 33LV
4 parts by weight, 0.22 parts by weight of NIAX A-1 and 0.26 parts by weight of tin octylate were added and mixed at high speed. afterwards,
Immediately TDI-80 (NCO / OH index 9
8) was added, the mixture was further stirred at a high speed, and placed in a 40 × 40 × 10 cm box adjusted to the temperature shown in Table 3. After foaming is completed,
It was put in a curing oven and cured. The physical properties of the obtained polyurethane foam were measured and shown in Table 3 together with the foam state. As shown in Table 3, in the mold temperature range of 30 to 60 ° C, a polyurethane foam having a good foam state and good physical properties was obtained.

Comparative Example 5-8 Examples 13 to 16 except that VS-7207 was not added.
A polyurethane foam was prepared in the same manner as in 1. and the physical properties were measured. As shown in Table 3, in the comparative example in which VS-7207 was not used, defective foam state was observed at mold temperatures other than 40 ° C.

[0023]

[Table 3]

[0024]

According to the method for producing a flexible polyurethane foam containing the low molecular weight polydiorganosiloxane of the present invention, even when only water is used as a foaming agent without using halocarbons,
The mold temperature range can be widened, and a flexible polyurethane foam having good properties can be produced.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08G 18/00-18/87

Claims (3)

(57) [Claims] 1. A method of producing a polyurethane foam by high temperature curing mold foaming using a polyol component, an isocyanate compound, water, a catalyst, a foam stabilizer and an additive, wherein a general formula (1): (Wherein, R is the same or different organic groups having 1 to 6 carbon atoms, and m is an integer of 3 to 7), and the low molecular weight polydiorganosiloxane of the cyclic polydiorganosiloxane is represented by 100 parts by weight of the polyol component. 0.02 to part
A method for producing a flexible polyurethane foam obtained by high-temperature-curing mold foaming, which comprises 1.0 part by weight. 2. The polyol component has a functional group number of 2.5 to
3. The method according to claim 1, wherein the number average molecular weight is 3.5 and the number average molecular weight is 2,000 to 8,000 and 30% or more of the hydroxyl groups are primary polyether polyols. 3. A flexible polyurethane foam produced by the method according to claim 1.