JPH07109370A - Production of water-shielding polyurethane foam - Google Patents

Abstract

PURPOSE:To obtain a water-shielding polyurethane foam having water-shielding performance and low gas-permeability by using an epoxy(or methacryl)-modified organosilicone as a foam stabilizer. CONSTITUTION:The urethane foam is composed of (A) a polyhydroxyl compound, (B) an isocyanate, (C) a foaming agent, (D) a catalyst and (E) a foam stabilizer consisting of one or more silicones selected from epoxy-modified organosilicone and methacryl-modified organosilicone. The component E is e.g. a compound of the formula I [R1 is group of the formula II (A is group of the formula III; (n) is 1-10; (n') is 1-20; (a) and (b) are 1-50; the molar ratio of a/b is 3/1); (x) is 1-300; (y) is 1-25]. The amount of the component E is preferably 0.3-5 pts.wt. based on 100 pts.wt. of the component A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention has low air permeability and
The present invention relates to a method for producing a flexible or semi-rigid open-cell polyurethane foam having a water blocking property.

[0002]

2. Description of the Related Art Conventionally, as a method for producing a soft or semi-rigid open-cell polyurethane foam having low air permeability and waterproofness, (1) a soft or semi-rigid open-cell polyurethane foam is treated with a volatile solution of asphalt. A method of impregnating and drying, and (2) a polydiene-based polyol, a dimer acid polyol, and a combination of at least one kind of a polyol obtained by addition-polymerizing 90% or more of an alkylene oxide having 3 or more carbon atoms with a hydroxyl group-containing organosilicone Method for producing semi-rigid open-cell polyurethane foam sealing material (Japanese Patent Publication No. 2-55)
470), (3) a method for producing a polyurethane foam sealing material having a polyolefin skeleton as a polyol (JP-A-63-27583), (4) a saturated hydrocarbon resin skeleton polyurethane foam using a hydroxyl group-containing reactive silicone. A method for producing a sealing agent (Japanese Patent Laid-Open No. 2-298574) and the like are known.

[0003]

However, in these methods, as for (1), the problems of environmental pollution due to the solvent even in the drying step, the productivity of the foam and the phenomenon of thinning the meat after foaming,
Regarding (2), the foam has a high density (40 kg /
m ³ ), there is no problem in appearance, but the problem that void-like pinholes or cracks are generated in the foam in the low density region, (3) and (4) are not economical. There's a problem.

Further, conventionally, in the case of producing a flexible or semi-rigid open-cell polyurethane foam, generally, a polyether or polymer polyol mainly composed of propylene oxide having a molecular weight of 450 to 8000 is tolylene diisocyanate and a blowing agent. Although foaming is performed using a foam stabilizer, it is relatively easy to produce a foam having low air permeability depending on the type of polyol or the type or amount of amine catalyst selected at this time, No water blocking effect can be expected.

The present invention has been made in view of the above circumstances, and by using a specific foam stabilizer, a polyurethane having low air permeability and a water blocking effect without using a special polyol or a special additive. It is intended to provide a method for producing a foam.

[0006]

Means and Actions for Solving the Problems As a result of intensive studies to achieve the above object, the present inventor has found that one or more selected from epoxy-modified organosilicone and methacryl-modified organosilicone as a foam stabilizer. Foaming formulations containing polyhydroxyl compounds, isocyanates, blowing agents, catalysts with silicones of low breathability and water-stopping effect without the use of special polyols or special additives. The inventors have found that a flexible or semi-rigid polyurethane foam can be obtained, and completed the present invention.

Accordingly, the present invention is directed to a process for making a flexible or semi-rigid polyurethane foam from a formulation containing a polyhydroxyl compound, an isocyanate, a blowing agent, a catalyst and a foam stabilizer, as a foam stabilizer an epoxy-modified organosilicone and methacryl. Provided is a method for producing a water-proof polyurethane foam, which comprises using one or more kinds of modified organosilicones.

The present invention will be described in more detail below.

The method for producing a water-proof polyurethane foam of the present invention uses a composition comprising a polyhydroxyl compound (polyol), an isocyanate, a foaming agent, a catalyst, a foam stabilizer, and other additives optionally added. When producing an open-celled flexible or semi-rigid polyurethane foam, by using a modified silicone with epoxy or methacryl as a foam stabilizer, a flexible or semi-rigid open-celled polyurethane foam can be used without selecting a specific polyol. Is about how to get.

As the epoxy-modified silicone, those represented by the following formulas (1) to (3) are preferable.

[0011]

[Chemical 1]

[0012]

[Chemical 2] (However, R ₂ is C _n H _2n O (C ₂ H ₄ O) _a (C ₃ H ₆ O) _b C
_{n 'H 2n' + 1} or _{C n H 2n O (C 2} H 4 O) a (C 3 H 6 O) b O
_{C n 'H 2n' + 1} , x, y, A is the same as above. )

[0013]

[Chemical 3] (However, x, y, A are the same as the above.)

As the methacrylic modified organosilicone, those represented by the following formula (4) are preferably used.

[0015]

[Chemical 4] (However, R ₁ is C _n H _2n O (C ₂ H ₄ O) _a (C ₃ H ₆ O)
_b B, B is _{C n 'H 2n' OC (} CH 3) = CH 2, x is 1 to 3
00, y is 1 to 25, n is 1 to 10, n'is 1 to 20,
a and b are 1 to 50, and the molar ratio of a and b is 3/1 to 1
/ 3, respectively, and the others are the same as those described above. )

The amount of the silicone (foam stabilizer) blended is preferably 0.3 to 5 parts, and more preferably 0.5 to 2 parts, relative to 100 parts (parts by weight, hereinafter the same) of the polyhydroxyl compound. 5 copies. If the amount of the silicone compounded is less than 0.3 part, the foam regulating ability is lowered, and it is difficult to obtain a foam having a good appearance. If it is more than 5 parts, the proportion of closed cells in the foam is increased, and a good foam is obtained. There are cases where it does not exist.

In the present invention, as the components other than the above silicone (foam stabilizer), known ones used for producing a flexible polyurethane foam or a semi-rigid polyurethane foam can be used.

Specific examples of the polyhydroxy compound include polyether polyol and polyester polyol. As a polyether polyol,
Polyhydric alcohols such as ethylene glycol, glycerin, and trimethylolpropane that are addition-polymerized with alkylene oxides having 3 or more carbon atoms, such as propylene oxide, butylene oxide, or a mixture thereof, or polymer polyols obtained by graft-polymerizing styrene or acrylonitrile. Is preferred.

The average molecular weight of the polyether polyol is
It is 450 to 8000, preferably 550 to 6000, and the average number of functional groups is 2 to 4.5, and particularly 2 to 4 is preferable.

Polyolefin polyols are also preferably used. If this polyolefin polyol is used by blending it with other polyols as needed, the water repellent effect of the polyolefin and a highly functional water blocking effect can be obtained.

Examples of polyester polyols include polydiene-based polyols, dimer acid-based polyols, castor oil-based polyols and other adipic acids, polyhydric carboxylic acids such as phthalic acid, and ethylene glycol, propylene glycol, diethylene glycol, trimethylolpropane, and the like. Those obtained from polyhydric alcohols are mentioned,
These may be used alone or as a mixture.

As the isocyanate compound, tolylene diisocyanate, polymethylene polyethylene polydiisocyanate, hexamethylene diisocyanate, 1,
5-naphthalene diisocyanate, xylene diisocyanate, isophorone diisocyanate and the like are used.

The amount of the isocyanate compound blended is preferably 20 to 75 parts with respect to 100 parts of the polyhydroxyl compound, but is not particularly limited thereto.

As the foaming agent, water, methylene chloride and the like are used, but the foaming agent is not limited to these.

As the catalyst, tertiary amines, tertiary amine complex salts, organotin compounds, etc. are used. For example, triethylenediamine, triethylenediamine complex salts, triethylamine, bisdimethylaminoethyl ether complex salts, bisdimethylamino. N-methylmorpholine of ethyl ether, stannous octylate, stannous dibutyl laurate and the like are preferable.

In addition, additives such as ultraviolet absorbers, antioxidants and pigments are used as necessary.

The blending amount of the blowing agent and the catalyst is not particularly limited, but the blending amount of the blowing agent is generally 1 to 6 parts with respect to 100 parts of the polyhydroxyl compound, and the blending amount of the catalyst is 0.1 to 3 parts. It is preferably part.

In the present invention, the above components are mixed to obtain a blend, which is foamed according to a conventional method to obtain a flexible semi-rigid polyurethane foam.

In this case, since the epoxy-modified organosilicone requires a certain amount of heat (about 100 ° C.) in the presence of an alkali to open the ring, as shown in the following formula, the ring is not opened until the reaction is completed. The foaming ability is maintained, the ring is opened and reacted before the completion of the reaction of the entire system, so that foaming is not hindered, and a foam having a good appearance, low air permeability and water blocking effect is provided.

[0030]

[Chemical 5]

Further, the methacryl-modified organosilicone reacts with other raw materials in the entire reaction process as shown in the following formula, and finally reacts while maintaining the foam-stabilizing ability to some extent to form a system. It is taken in and brings about low air permeability and water blocking effect.

[0032]

[Chemical 6]

In the present invention, the foaming conditions are appropriately selected, but the foaming time (rise time) is usually about 30 seconds to 3 minutes.

The reaction rate can be generally controlled with an amine catalyst, but the amine-tin catalyst has a strong activity and cannot be delicately controlled.

[0035]

According to the present invention, a soft or semi-rigid polyurethane foam having a low air permeability and a water blocking effect can be obtained by using the above-mentioned specific silicone.

[0036]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

In the present invention, breathability means J
According to the Frazier type of IS L1004, the foam thickness was measured at 10 mm.

As for the water stopping property, as shown in FIGS. 1 and 2, a foam sample 1 having a thickness of 10 mm was punched out in a U shape (see FIG. 2) to obtain a 50% strength between two acrylic plates 2 and 2. It was sandwiched in a compressed state, water 3 was put into this U-shaped body at a predetermined height H, and the leakage time due to water pressure was measured to evaluate. In the figure, 4 is a spacer and 5 is a bolt.

[Examples 1 and 2 and Comparative Example 1] Molecular weight 3000 obtained by addition-polymerizing propylene oxide to glycerin.
100 parts of (OH number 56) polyether polyol, 60.453 parts of tolylene diisocyanate, 4.6 parts of water,
As a catalyst, 0.3 part of tolylenediamine (33LV), 0.3 part of stannas octoate, and 4.0 of methylene chloride.
Parts, a composition using 1.5 parts of an epoxy-modified organosilicone represented by the following formula (5) as a foam stabilizer was foamed to obtain a flexible polyurethane foam (Example 1).

A flexible polyurethane foam was obtained in the same manner as above except that the methacryl-modified organosilicone represented by the following formula (6) was used (Example 2).

For comparison, a flexible polyurethane foam was obtained in the same manner as described above except that the terminal alkyl cap type silicone represented by the following formula (7) was used (Comparative Example 1).

Table 1 shows the physical properties of the obtained polyurethane foam.

[0043]

[Chemical 7]

[0044]

[Chemical 8]

[0045]

[Chemical 9]

[0046]

[Table 1]

[Examples 3 and 4] Hydrogenated terminal hydroxylated polyisoprene polyol (OH number 40) and dimer acid type polyester polyol (OH number 72) were blended in a weight ratio of 4: 1 and 100 parts thereof were blended. To water 2.0 parts, TDI
30 parts of 80, triethylenediamine 0.3 as a catalyst
And 0.5 parts of stanna octate and 1 part of the same epoxy-modified silicone (Example 3) or methacryl-modified silicone (Example 4) as in Examples 1 and 2 as a foam stabilizer were added to foam the resulting mixture. Then, a flexible polyurethane foam was obtained. The physical properties are shown in Table 2.

[0048]

[Table 2]

[Brief description of drawings]

FIG. 1 is a view showing an apparatus for a water stop test.

FIG. 2 is a diagram showing a foam sample.

[Explanation of symbols]

 1 Foam sample 2 Acrylic board 3 Spacer 4 Bolt 5 Water

[Procedure amendment]

[Submission date] September 13, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

[0011]

[Chemical 1]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08G 101: 00) C08L 75:04

Claims (2)

[Claims] 1. A method of making a flexible or semi-rigid polyurethane foam from a formulation containing a polyhydroxyl compound, an isocyanate, a blowing agent, a catalyst and a foam stabilizer, said method comprising:
A method for producing a water-proof polyurethane foam, which comprises using one or more silicones of epoxy-modified organosilicone and methacryl-modified organosilicone as a foam stabilizer. 2. A polyhydroxyl compound 100 as a foam stabilizer.
The method for producing a waterproof polyurethane foam according to claim 1, wherein 0.3 to 5 parts by weight is used with respect to parts by weight.