JPH0381314A - Production of highly resilient polyurethane foam - Google Patents

Abstract

PURPOSE:To produce a highly resilient polyurethane foam having a high impact resilience and offering excellent cushioning properties and comfortableness when used for an automobile seat, furniture, etc., by reacting an org. polyisocyanate with a high-molecular polyol component comprising two specific polyols. CONSTITUTION:A process for producing a polyurethane foam by reacting an org. polyisocyanate with a high-molecular polyol in the presence of a catalyst, a blowing agent, a foam stabilizer, and if necessary a crosslinker and other additives, wherein the high-molecular polyol is a mixture of a polyol (A) having a functionality of 3, a hydroxyl number of 22-35, pref. 24-31, and a terminal polyoxyethylene chain content of 5-25wt.%, pref. 14-16wt.% and a polyol (B) having a functionality of 4, a hydroxyl number of 22-40, pref. 28-35, and a terminal polyoxyethylene chain content of 5-25wt.%, pref. 10-14wt.% in a wt. ratio of A to B of (38:62)-(90:10), pref. (50:50)-(80:20). Thus, a highly resilient polyurethane foam is produced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for producing highly elastic polyurethane foam.

[Conventional technology] Conventionally, as a method for manufacturing high elastic polyurethane foam,
Reacting an organic polyisocyanate with a polymeric polyol having a relatively large molecular weight having 3 or 4 functional groups and a high ethylene oxide content in the presence of a catalyst, a blowing agent, a foam stabilizer, and if necessary a crosslinking agent and additives. method is known.

[Problem M to be Solved by the Invention] However, in this method for producing polyurethane foam, there is a limit to the resistance elasticity, which is a feature of high elasticity polyurethane foam.

[Means for Solving the Problems] The present inventors have developed a method for producing a highly elastic polyurethane foam that can further increase the anti-elasticity. In the method for producing polyurethane foam by reacting in the presence of a polymeric polyol, the polymeric polyol has a functional group number of 3.
A polyol (A) containing 5 to 25% polyoxyethylene chain based on the weight of (A) at the terminal end with a hydroxyl value of 22 to 35 and a functional group number of 4 and a hydroxyl value of 22 to 4.
consisting of a polyol (8) containing 5 to 25% polyoxyethylene chains based on the weight of (B) at the end of 0, the weight ratio of (A)/(B) being 38/62 to 90/ 10
A method for producing a highly elastic polyurethane foam characterized by using a polyol that is 3. The method according to claim 1 or 2, wherein at least a portion thereof is modified with an ethylenically unsaturated monomer.

Examples of the polyol (A) used in the present invention include compounds having a structure in which an alkylene oxide is added to a compound having a functional group number of 3 and three active hydrogen atoms (for example, alcohols and amines), and mixtures thereof. It will be done.

Examples of alcohols include trihydric alcohols such as glycerin, trimethylolpropane, trimethylolethane, and hexanetriol; examples of amines include alkanols such as ammonia, mono-, di-, and triethanolamine, isopropanolamine, and aminoethylethanolamine. Examples include amines and heterocyclic amines such as aminoethylpiperazine.

Two or more of these active hydrogen atom-containing compounds may be used in combination. Among these, alcohols are preferred.

The alkylene oxides to be added to the active hydrogen atom-containing compound include ethylene oxide (hereinafter abbreviated as EO), propylene oxide (hereinafter abbreviated as PO), 1.2
Examples include -11,3-11,4-12,3-butylene oxide, styrene oxide, etc., and combinations of two or more of these, preferably EO1P○ and combinations of EO and PO. Addition formats when used in combination include block and/or random addition, and preferred are (1) block addition in the order of PO-EO;
(2) Block addition in the order of PO-EO-PO-EO, (3) Block addition in the order of EO-PO-EO, (4) Random addition of PO and EO, (5H4). It is a block addition in the order of random adduct-EO. These may be used in combination.

The hydroxyl value of the polyol (A) used in the present invention is 22 to 3
5, preferably 23-33, particularly preferably 24-31
It is. If the hydroxyl value is less than 22, the hardness of the foam will drop significantly and the compression set will worsen; if it exceeds 35, the resistance elasticity, which is the object of the present invention, will drop significantly and the foam will tend to form a bleed foam. Terminal EO of polyol (A)
The amount is between 5 and 25%, preferably between 10 and 18%, particularly preferably between 14 and 16%. If the terminal EO content is less than 5%, molding defects such as collapse will occur in the foam, and the terminal E
If the amount of O exceeds 25%, molding defects such as air bleed will occur in the foam.

Examples of the polyol (B) used in the present invention include compounds having a structure in which an alkylene oxide is added to a compound having a functional group number of 4 and 4 active hydrogen atoms (for example, alcohols and amines), and mixtures thereof. It will be done.

Examples of alcohols include tetrahydric alcohols such as pentaerythritol, methyl glucoside, and diglycerin; examples of amines include ethylenediamine, propylenediamine,
Examples include alkylene diamines such as hexamethylene diamine. Two or more of these active hydrogen atom-containing compounds may be used in combination. Among these, alcohols are preferred. As the alkylene oxide to be added to the active hydrogen atom-containing compound, the same alkylene oxides as those explained for polyol (A) can be used, and the same types of addition can also be used.

The hydroxyl value of the polyol (B) used in the present invention is 22 to 4
0, preferably 25-37, particularly preferably 28-35
It is. If the hydroxyl value is less than 22, the hardness of the foam will decrease significantly and the compression set will deteriorate significantly, and if the hydroxyl value is less than 40
If it exceeds this value, the resistance elasticity, which is the object of the present invention, will be significantly lowered, and a crazy form will likely occur. Polyol (
The terminal EOi of B) is 5-25%, preferably 8-18
%, particularly preferably 10 to 14%. Terminal EO,!
If it is less than 5%, molding defects such as collapse will occur in the foam, and if the terminal EO amount exceeds 25%, molding defects such as deformation will occur in the foam. The weight ratio of polyol (A)/polyol (B) is 3B/62 to 90/10,
Preferably 43157 to 85/15.

Particularly preferred is 50,150 to 80/20. (A)
When the weight ratio of is less than 38 or greater than 90, and (
When the weight ratio of B) is less than 10 or greater than 62, the resistance elasticity when formed into a foam is not improved.

In the present invention, polyol (A) and polyol (B)
) may be at least partially modified with an ethylenically unsaturated monomer. It may also be a so-called polymer polyol.

Monomers used in the production of polymer polyols include:
The following may be mentioned: (1) Acrylic acid, methacrylic acid and derivatives thereof: acrylonitrile, methacrylonitrile, acrylic acid,
Methacrylic acid and its salts, methyl acrylate, methyl methacrylate, dimethylaminoethyl methacrylate, acrylamide, methacrylic acid amide, etc.

(11) Aromatic vinyl monomers: styrene, α-methylstyrene, etc.

(ill> Olefinic hydrocarbon monomer; ethylene, propylene, butadiene, isobutylene, isoprene, 1
, 4-pentagene, etc.

0ψvinyl ester monomer: vinyl acetate, etc.

(v) Vinyl halide monomer: vinyl chloride, vinylidene chloride, etc.

(vD vinyl ether monomer: vinyl methyl ether, etc.

Among these, preferred are acrylonitrile, methyl methacrylate, styrene, and butadiene. Particularly preferred is acrylonitrile, a combination of acrylonitrile and styrene (styrene:acrylonitrile weight ratio 5).
:95-95:5).

When using a trifunctional polyol and a tetrafunctional polyol that have both been modified, the trifunctional unmodified polyol and the tetrafunctional unmodified polyol may be mixed and modified,
Further, a trifunctional modified polyol and a tetrafunctional modified polyol may be mixed.

The ratio of monomers used for modification can be varied over a wide range, but usually polyols [polyol (A), polyol (B), and polyol (^) and polyol (B
) The amount of the ethylenically unsaturated monomer or polymer is usually 2 to 100 parts by weight, preferably 2 to 80 parts by weight, and particularly preferably 2 to 55 parts by weight.

Modification of a polyol with an ethylenically unsaturated monomer (production of a polymer polyol) can be carried out by a conventional method. For example, a method in which an ethylenically unsaturated monomer is polymerized in a polyol in the presence of a polymerization catalyst (radical generator, etc.) (U.S. Pat. No. 3,313,351, Japanese Patent Publication No. 39-24
No. 787, JP 47-47999, JP 50-1
5894) and a method in which a polymer obtained by prepolymerizing the above monomers and a polyol are graft-polymerized in the presence of a radical generator (Japanese Patent Publication No. 47-47597). The former method is preferred. As the polymerization catalyst (radical generator) used in the polymerization reaction, azo compounds, peroxides, persulfates, perborates, etc. can be used, but azo compounds and peroxides are preferred in practice. The amount used is also not particularly limited, and for example, 0.1 to 100 parts by weight of the ethylenically unsaturated monomer (or polymer).
The amount is 20 parts by weight, preferably 0.1 to 15 parts by weight. The above polymerization can also be carried out in the presence of a solvent such as toluene, xylene and the like. The reaction temperature is usually 50 to 170
℃, preferably 90 to 150℃.

When polyol (A) and polyol (B) are not modified with ethylenically unsaturated monomers, polyol (^
) has a hydroxyl value of 22 to 35, preferably 23 to 33, particularly preferably 24 to 31. Further, the hydroxyl value of polyol (8) is 22 to 40, preferably 25 to 37, particularly preferably 28 to 35, but at least a part of polyol (A) and polyol (13) is an ethylenically unsaturated monomer. When modified with polyol (A), the hydroxyl value of the modified polyol (A) is usually 11-34, preferably 12-34. 32, particularly preferably 14 to 30, modified polyol (I3
) has a hydroxyl value of usually 11 to 39, preferably 12 to 36.
, particularly preferably 14-34.

Moreover, when at least a part of polyol (A) and polyol (F3) is modified with an ethylenically unsaturated monomer, modified polyol (A)/modified polyol (B)
The weight ratio is the same as in the unmodified case, 3B/82 ~
90/10, preferably 43157 to 85/15, particularly preferably 50150 to 80/20. (In this case, the weight ratio was determined by excluding the weight of acrylonitrile and the polymer obtained by polymerizing acrylonitrile and an ethylenically unsaturated monomer such as styrene.) Conventional organic polyisocyanates used in the present invention Those used in the production of polyurethane can be used. Such polyisocyanates include aromatic polyisocyanates having 6 to 20 carbon atoms (excluding carbons in the NGO group) (for example, 2.4- and/or 2,
6-Tolylene diisocyanate (TDI), crude TDI
, 2,4′-and/or 4,4°-diphenylmethane diisocyanate ()IDI), crude)IDI
[Crude diaminophenylmethane (condensation product of formaldehyde and an aromatic amine (aniline) or a mixture thereof diaminodiphenylmethane and a small amount (e.g.
Phosgenide dipolyallylpolyisocyanate (PAP
I) etc.Aliphatic polyisocyanates having 2 to 18 carbon atoms (e.g. hexamethylene diisocyanate, lysine diisocyanate, etc.): Alicyclic polyisocyanates having 4 to 15 carbon atoms (e.g. inphorone diisocyanate, dicyclohexylmethane diisocyanate): Number of carbon atoms 8 to 15 aromatic aliphatic polyisocyanates (for example, xylylene diisocyanate, etc.); and modified products of these polyisocyanates (urethane group, carbodiimide group, allophanate group, urea group, biuret group, uretdione group, uretonimine group, insia nurate group, oxazolidone group-containing modified products, etc.): and patent application 1973
Examples include polyisocyanates other than those described in JP 9-199160 and mixtures of two or more thereof.

Among these, commercially readily available polyisocyanates such as 1, 2, 4 and 2. B-TD
I.

and mixtures of these isomers, PAPI, also called crude) IDI, and modified polysaccharides containing urethane groups, carbodiimide groups, allophanate groups, urea groups, biuret groups, and isocyanurate groups derived from these polyisocyanates. It is an isocyanate.

The catalysts used in the present invention include catalysts commonly used in polyurethane reactions, such as amine catalysts (tertiary amines such as triethylenediamine and N-ethylmorpholine), tin catalysts (stannous octylate, dibutyltin dilaurate, etc.), etc.), other metal catalysts (lead octylate, etc.)
can be used.

As the blowing agent, for example, water, monofluorotrichloromethane, methylene chloride, etc. can be used. Examples of foam stabilizers include silicone surfactants (polysiloxane-polyoxyalkylene copolymers).

Examples of crosslinking agents that may be used as necessary include polyhydric alcohols, and polyhydric alcohols to which a small amount of alkylene oxide as described for polyol (A) is added [diethylene glycol, glycerin, and EO added to glycerin, which has a molecular weight of 600. , EO to sorbitol
(molecular weight 800, etc.), amines, and amines with a small amount of alkylene oxide added to polyol (A) [jetanolamine, triethanolamine, triethanolamine with EO added ( molecular weight 600), ethylenediamine 10
Next, a compound with EO added (molecular weight aOO, etc.) can be used. These may be used in combination. Examples of additives include flame retardants, colorants, anti-aging agents, and antioxidants.

The amount of the organic polyisocyanate used in the present invention is generally 80 to 120, preferably 85 to 115, particularly preferably 95 to 110 in terms of incyanate index.

The amount of catalyst used is, for example, from about 0.001 to about 5%, based on the weight of the reaction mixture. The amount of blowing agent used can be varied depending on the desired density of the polyurethane foam;
For example, from about 1% to about 20%, based on the weight of the reaction mixture. The amount of foam stabilizer used is based on the weight of the reaction mixture.
For example, about 0.1 to about 5%. The amount of crosslinking agent optionally used can vary depending on the desired hardness of the polyurethane foam, for example from about 1% to about 20%, based on the weight of the reaction mixture. The amount of additive used can vary depending on the desired goals for various polyurethane foam applications, such as from about 0.05 to about 30 percent, based on the weight of the reaction mixture. The highly elastic polyurethane foam can be produced by a conventional method, and can be carried out by a known method such as a one-shot method, a semi-prepolymer method, or a prepolymer method. Highly elastic polyurethane foam is produced by mixing and reacting raw materials in commonly used production equipment (low-pressure or high-pressure mechanical equipment). Useful in foam manufacturing.

[Examples] The present invention will be specifically explained below using practical examples, but the present invention is not limited to these examples.

The composition of the raw materials used in the Examples and Comparative Examples is as follows.

(1) Polyol A-1 A polyol with a hydroxyl value of 31, which is obtained by adding PO to glycerin and then adding EO. The amount of terminal addition of EO is 16%
It is.

(2) Polyol^-2 A polyol with a hydroxyl value of 28, which is obtained by adding PO to glycerin and then adding EO. The amount of terminal addition of EO is 18%
It is.

(3) Polyol A-3 A polyol with a hydroxyl value of 24, which is obtained by adding PO to glycerin and then adding EO. The amount of terminal addition of EO is 14%
It is.

(4) Polyol B-1 A polyol with a hydroxyl value of 35, which is obtained by adding PO to pentaerythritol and then adding EO.

The terminal addition amount of EO is 10%.

(5) Polyol B-2 A polyol with a hydroxyl value of 32, which is obtained by adding PO to pentaerythritol and then adding EO.

The terminal addition amount of EO is 12%.

(6) Polyol B-3 A polyol with a hydroxyl value of 28, which is obtained by adding PO to pentaerythritol and then adding EO.

The terminal addition amount of EO is 10%.

(7) Polyol ■ Polyol A-1/Polyold 1 = 50150 (w
Blend with t.

(8) Polyol ■ Polyol A-2/Polyol B-2 = 50150 (w
Blend with t.

(9) Polyol ■ Polyol A-3/Polyol B-3 = 50150 (w
Blend with t.

(10) Polyol 1v Polyol A-2/Polyol B-2 = 30/70 (W
Blend with t.

(11) Polyol ■ Polyol A-2/Polyol B-2 = 70/30 (W
Blend with t.

(12) Polyol C-1 Polyol 100 with a hydroxyl value of 33, made by adding PO to glycerin and then adding EO (terminal addition amount: 14%)
part and acrylonitrile as ethylenically unsaturated monomer
Hydroxyl value 27 obtained by reacting 5 parts at a temperature of 130°C with 1.0 part of azobisisobutyronitrile as an initiator.
polyol.

(13) Polyol C-2 100 parts of polyol A-2, 27 parts of acrylic and ronitrile as ethylenically unsaturated monomers, and 15 parts of styrene in 1 part
A polyol with a hydroxyl value of 20 obtained by reacting 0.2 part of bis(4-mo-butylcyclohexyl)peroxydicarbonate at a temperature of 20°C as an initiator.

(14) Polyol C-3 2100 parts of polyold, 27 parts of acrylonitrile and 15 parts of styrene as ethylenically unsaturated monomers in 120 parts
A polyol having a hydroxyl value of 22 obtained by reacting 0.2 parts of bis(4-t-butylcyclohexyl) peroxydicarbonate as an initiator at a temperature of .degree.

(15) Polyol C-4 120 parts of polyol vioo and 27 parts of acrylonitrile and 15 parts of styrene as ethylenically unsaturated monomers
A bool having a hydroxyl value of 20 obtained by reacting 0.2 part of bis(4-1-butylcyclohexyl) peroxydicarbonate as an initiator at a temperature of .degree.

(16) Catalyst-1 Dabco53LV (33% of triethylenediamine
Dipropylene glycol solution> (17) Catalyst-2 Polycat 41 (amine catalyst) [manufactured by San-Apro ■] (18) Foam stabilizer-1 L-3309 (polyether siloxane polymer) [Nippon Unicar (manufactured by 1M Co., Ltd.) 1) Foam stabilizer-2 5RX-274G (Polyether siloxane polymer)
[Tote Silicone Co (20) Incyanate Coronate 1021 [T-80/Cr-)tDI=8
/2 (wt) Co [manufactured by Nippon Polyurethane Industry ■] Examples 1 to 11 and Comparative Examples 1 to 7 Using polyols A-C1 and ■ to V, high elasticity HR-foam was molded by hand foaming under the following conditions. did.

[Molding conditions] Liquid temperature: 25°C Cure temperature: 70°C Cure time: 5 minutes Mold temperature: 55-60°C Mold size: 40X 40X The 10-mark foaming formula and the physical properties of the obtained foam are shown in Tables 1 and 2. .

The method for measuring physical properties is as follows.

Density (kg/rri'): JIS 630125%ILD (kg/314ai):
JIS K 6382 tensile strength (lucid/cnt)
: JIS K 6301 tear strength (kg/equipment)
: JISK6301 cutting elongation (%”) :
JIS K 6301 rebound modulus (%):
JIS K 63B2 Compression set (%): J
IS K 6382 Table 1 Table 2 Table 3 Table 4 Example 1 Polyol (1) ■ ■ Polyol (2) -2 -4 Polyol (3) -3 Polyol (1) (g) 0 60' Polyol (2) ( g) 8 0 Polyol (3) (g) 2 Triethanolamine (g) Water (g> 3.0 3.0 Catalyst-1 (g> 0.4 0.4 Catalyst-2 (g) 0.1 0 .1 Foam stabilizer-2 (g> 0.4 0.4 Foam stabilizer-1 (g) 0.3 0.3 Isocyanate (g) 45.3 45.3 NCOIndex 05 05 (Foam physical properties) Total density ( 48.5 48.2 Core density (kg/m) 42.6 42.4 Tensile strength (Mackerel/-) 1.37 1.35 Cutting elongation (%) 5 7 Tear strength (pupil/am ) 0.64 0.62 25% ILD (kg/314a &>'21.4 21.6 Compression set (%) 3.1 3.1 Heat set (%) 12.2 12.1 Table 5 Table 6 Table 7 [Effects of the Invention] The method for producing a highly elastic polyurethane foam of the present invention can produce a foam that has better resilience than conventional methods.

Due to the above-mentioned effects, the polyurethane foam obtained by the present invention is extremely useful for applications such as automobile seats and furniture, as it has excellent cushioning properties and ride comfort.

Claims (1)

[Claims] 1. A method for producing polyurethane foam by reacting an organic polyisocyanate and a polymeric polyol in the presence of a catalyst, a blowing agent, a foam stabilizer, and optionally a crosslinking agent and additives, which comprises A polyol (A) having a functional group number of 3 and a hydroxyl value of 22 to 35 and containing a polyoxyethylene chain of 5 to 25% based on the weight of (A) at the terminal end, and a polyol (A) having a functional group number of 4 and a hydroxyl value of 22 to 35 as a polyol. consisting of a polyol (B) containing 5 to 25% polyoxyethylene chains based on the weight of (B) at 22 to 40 terminal ends;
A method for producing a highly elastic polyurethane foam, characterized by using a polyol having a weight ratio of A)/(B) of 38/62 to 90/10. 2. The method according to claim 1, wherein at least a portion of (A) is modified with an ethylenically unsaturated monomer. 3. The method according to claim 1 or 2, wherein at least a portion of (B) is modified with an ethylenically unsaturated monomer.