JPH03239715A - Wet heat-resistant flexible polyurethane foam - Google Patents

Abstract

PURPOSE:To obtain the title foam improved in wet heat resistance and hand by reacting an organic diisocyanate with a specified polyester polyol, a blowing agent, a catalyst and a surfactant. CONSTITUTION:An acid component comprising sebacic acid or both this acid and other dicarboxylic acids is reacted with a polyhydric alcohol component comprising trimethylolpropane, 40-80mol% diethylene glycol and 60-20mol% 1,6-hexanediol and/or 3-methyl-1,5-pentanediol at 150-250 deg.C in the presence of a catalyst to obtain a polyester polyol of a number-average mol.wt. of 1000-4000 and a number-average functionality of 2.4-4.0. This polyester polyol is mixed with an organic diisocyanate in an NCO to OH ratio of 0.9-1.2, and the mixture is cured by heating in the presence of a blowing agent, a catalyst and a surfactant.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a flexible polyurethane foam, and more specifically, it is a flexible polyurethane foam that is resistant to moisture and heat and has an excellent texture by using a special copolyester polyol. It's about form.

[Conventional technology]

It has been known that so-called sepacic acid-based polyester polyols, which are obtained by reacting sebacic acid and aliphatic glycol, have excellent water resistance. On the other hand, poly(
Hexamethylene adipate)-based polyester polyols are not only useful as raw materials for polyurethane, but also
Regular poly(ethylene adipate) yarn, poly(propylene adipate) type, poly(diethylene adipate) yarn,
It is also well known that polyurethanes derived from polyester polyols such as poly(butylene adipate) systems also exhibit hydrolytic resistance.

However, sebacic acid-based polyester polyols and poly(hexamethylene adipate)-based polyester polyols have high crystallinity and are not practical for use alone in flexible polyurethane foams. Many cases do not have liquid properties at room temperature, and even if they were liquid, if they were made of polyurethane foam, they would shrink or cave in, making it impractical. Furthermore, adipate to which some neopentyl glycol is added has been proposed, but it has not had the effect of reducing crystallinity even if some improvements have been made in terms of physical properties.

[Problem to be solved by the invention]

The present inventors obtained a polyester polyol for flexible polyurethane which has the advantages of sebacic acid-based polyester polyol and poly(hexamethylene adipate)-based polyester polyol and does not have the disadvantages of WJ" The present invention was achieved as a result of repeated research and study on the use of flexible polyurethane foam for making knives.

[Means to solve the problem]

That is, in the present invention, when obtaining a flexible polyurethane foam from an organic diisocyanate, a polyester polyol, a blowing agent, a bile medium, and a surfactant, the polyester polyol contains sebacic acid or a combination of sebacic acid and another dicarboxylic acid as an acid component. and (a) trimethylolpropane, (b) diethylene glycol, and (c) 1,6 as a polyhydric alcohol component.
-hexanediol and/or 3-methyl-1,5-pentanediol in a molar ratio of (b) and (c) of 40 to 8
0%: A number average molecular weight of 1000 to 4000 obtained by reacting with 60 to 20 molar ratios, and a number average number of functional groups of 2.
It is a heat-and-moisture resistant flexible polyurethane foam characterized by having a molecular weight of 2 to 40.

The copolyester polyol, which is the raw material for obtaining the heat-and-moisture resistant flexible polyurethane foam of the present invention, has low crystallinity, is retractable at room temperature, is easy to handle, and can be easily processed into flexible polyurethane foam. . The humidity and heat resistance of the resulting flexible polyurethane foam is comparable to that of flexible polyurethane foams made from copolyester polyols obtained from the reaction of trimethylolpropane and diethylene glycol with adipic acid, which are currently mainly used as raw materials for flexible polyurethane foams. Much better than heat.

Sebacic acid or sebacic acid and another dicarboxylic acid (-1 trimethylolpropane, (b) diethylene glycol and (c) 1,6-hexanediol and/or
Or, for the reaction with 3-methyl-1,5-pentanediol, (1) Add (α), (phrase, and (c)) necessary to obtain a predetermined number average molecular weight to the dicarboxylic acid, and perform the reaction in a suitable manner. is 150 to 250°C, preferably 180 to 250°C in the presence of wild goose medium.
A method carried out at a temperature of 230°C.

■The theoretical amount of the dicarboxylic acid (-L(
b) and (c), preferably in the presence of a catalyst, 1
The reaction product'it is formed at a temperature of 50-250°C, preferably 180-230°C, and then trimethylolpropane is produced in a tube to a predetermined molecular weight under reduced pressure at a temperature of 150-250°C, preferably 180-230°C. and/or 3-
Methyl-1,5-pentanediol and/or 1,6-
The method (2), which is carried out while distilling off hexane glycol and/or diethylene glycol, is preferred, and in this way a copolyester polyol having a desired molecular weight can be produced.

Trimethylolpropane and/or 1,6-hexane glycol and/or 3-
The amount of methyl-1,5-pe/tanediol and/or diethylene glycol used is 1.1 to 20 times the theoretical amount, preferably 5 to 15 times the theoretical amount, and the degree of pressure reduction during the pressure reduction reaction is 200' ( At a reaction temperature of !, a door IQ of 3 to 5 ya is appropriate.

In addition, no matter which method is used, it is desirable to carry out the reaction in the presence of a catalyst in order to make the reaction proceed quickly.
In addition to general transesterification catalysts, organic sulfonic acids such as paradolenesulfonic acid can be used as well as compounds of metals such as titanium, zinc, soot, lead, and iron. Among these, titanium-tetra-alcokyds such as titanium-tetraisoproboquine are preferred, and the amount of these catalysts used is 5 to 5.
Concentrations as low as 0 ppm are suitable.

Reaction concentration is preferably 150-250'Q Fixso-2
The temperature is maintained at 30°C. At a low temperature such as 150° C. or lower, the reaction rate decreases significantly, and at a temperature higher than 250° C., a decomposition reaction of the copolyester polyol occurs, which is not favorable.

In order to proceed with the reaction, it is best to continuously remove the condensed water and/or the -hydric alcohol that are produced by the reaction from the system through an inert gas stream such as nitrogen.
It also prevents discoloration.

The time required to substantially complete such a reaction in a box (a) varies depending on the reaction conditions, 5 to 25 hours, 3 to 20 hours for the reaction in the pre-stage (2), and 3 to 3 hours for the reaction under reduced pressure. ~15 hours.

Made of copolyester polyol! K＞DeW,
Not only the dicarboxylic acid used as a dicarboxylic acid, sebacic acid, but also a mixture of sebacic acid and other dicarboxylic acids such as adipic acid and azelaic acid may be used.

Among the raw material polyols used in the present invention, trimethylolpropane is used to adjust the functional group a. The number average number of functional groups of the copolyester polyol is 2.
It is 2 to 4.0.

In this case, if it is less than 22, the moisture and heat resistance of the flexible polyurethane foam made from this copolyester polyol will be poor, and if it exceeds 4.0, the copolyester polyol will have a high viscosity, and in the production of flexible polyurethane foam, Mixing becomes insufficient, and the resulting foam tends to have poor physical properties.

3-) 1,5-hentanediol or 1,6-hexane glycol improves the heat and humidity resistance, and 3-methyl-1,5-pentanediol is effective against normal agitation. be. In addition, diethylene glycol contributes to the liquefaction of the normal current and also increases the M of the obtained flexible polyurethane foam.
It is effective for the same physical properties as L-warping.

In addition, the usage ratio of (2) diethylene glycol and (clt, 6-hexanediol) and/or 3-methyl-1,5-pentanediol is such that (b) = (c) is 40 to 80.
Mole φ: 60 to 20 moles.

In this case, the usage ratio of <b> diethylene glycol is 40
If it is less than molar, it tends to be difficult to maintain the liquefaction of the copolyester polyol at room temperature; If the diol is less than 20 moles φ, the resultant flexible polyurethane foam tends to have reduced moisture and heat resistance.

The flexible IJ urethane foam having moisture and heat resistance of the present invention is prepared by combining the above copolyester polyol, organic diisocyanate, blowing agent, catalyst, and additive caloric agent according to the list of interfacial lxl#i property agents. It can be obtained by curing.

In this case, the ratio of the inocyanate equivalent to the active hydrogen equivalent in the organic diyne 7-atom) L (NoO/10H) is 09
-1,2 preferably 0.95-1.05. If this ratio is less than 0.90, the molecular weight will not increase by 1,
Physical properties of soft polyurethane include tensile strength and ultimate elongation rate.

When mechanical properties such as tear resistance are poor, and R is 1.2 or more, the degree of crosslinking of the soft polyurethane structurally increases significantly, and the ultimate elongation rP decreases numerically.

Examples of the organic diisocyanate used in the present invention include hexamethylene diisocyanate, lysine diisocyanate, and lysine diisocyanate.
Aliphatic diisocyanates such as 4) lylene diisocyanate, phenylene diisocyanate), 4.
4'-diphenylmethane diisocyanate), 3.3'-
Examples include aromatic isocyanates such as dimethyltridine diisocyanate and naphthylene diisonoanate, and aliphatic diisocyanates such as 44'-dicyclohexylmethane diisocyanate and isophorone diynnyanate, or compounds of two or more thereof. .

A typical example of the reactive blowing agent used in the present invention is water, but other blowing agents known in the art can be used as necessary. These blowing agents may be used alone or in combination.

Examples of catalysts include tertiary amines such as triethylamine, triethylene diamine, pentamethylene diethylene triamine, dimethyl ethanolamine, and ethyl mole 7-olin, dibutyl tin dilaurate, dioctyl tin dilaurate, stanas oftate, and octenoates of various other metals. Although there are many metal catalysts, it is also possible to use a mixture of all of the above catalysts.

As the surfactant that can be used in the present invention, any surfactant that is effective for producing polyurethane foam can be used. Examples include polyoxyalkylene-based materials such as polyoxy/alkylene alkyl ether and polyoxyalkylene alkylamino ether, and silicone-based materials such as organopolysiloxane and siloxa/oxyalkylene copolymer.

Additives that can be used as necessary include anti-aging agents such as antioxidants and ultraviolet absorbers, fillers such as calcium carbonate and barium sulfate, flame release agents, star-forming agents, colorants, Examples include antifungal agents and the like that are known in the art.

The reaction conditions for soft polyurethanization include a one-shot method in which the above R is kept constant and the specified raw materials are simultaneously charged, and a method in which the entire amount of the copolyester polyol and diisocyanate and/or the copolyester polyol and diisocyanate are reacted at once, and then the remaining raw materials are reacted. A prepolymer addition method or a combination thereof is used, and the catalyst is often added from the beginning of the reaction.

These components are mixed and reacted using a known mixing device such as a low-pressure foaming machine, a high-pressure foaming machine, and a spray foaming agent.

Foaming can be done using any of the well-known methods such as the mold method, slab method, and spray method.

The flexible polyurethane foam treated in this way can be used mainly as a foamed elastic resin for general purposes such as clothing and footwear, and for industrial and industrial purposes.

〔Effect of the invention〕

The flexible polyurethane foam obtained by using the polyester polyol of the present invention has excellent texture and good heat and humidity resistance.

〔Example〕

The present invention will be explained in more detail with reference to Examples and Comparative Examples. Note that the number of functional groups and molecular weight of the polyester polyol are shown as number average values.

Example 1 Production of copolyester polyol Adipic acid 1264Ii (50 mol %) and sebacic acid 1748.9 (50 mol A total of 3012 mixed dicalphone Nl consisting of Prepare IT. Next, the total amount of a mixed glycol mixture of 1334 Il (75 mol) of diethylene glycol and 496 g (25 mol %) of 1,6-hexanediol and 280.9 mol of trimethylolpropane is 21
10! After I is fed, tetra-n is esterified as xi.
- Pour 1 m of butyl titanium and 130 ml of @ while stirring.
℃. Nitrogen is slowly passed through the system, and the water produced in the dehydration reaction is distilled out via a partial condenser. The temperature is raised to 210° C. while being careful not to distill the polyol component out of the reaction system. It is maintained at 210°C in a tube that no longer distills water. Next K: Keep it at 210℃ 2Q
The pressure is reduced to ryxHf, the acid value is confirmed to be 1.0 or less by sampling, and the reaction contents are cooled to a temperature of 1. In this way, a viscous copolyester polyol 1 was obtained.

Copolyester polyol 1 has a hydroxyl value (OHV) of 60
The valence of 61 (AV) was 0.4, the number of functional groups was 2.7, and the molecular weight was 2,500.

・Mixing recipe for manufacturing flexible polyurethane foam> Copolyester polyol 1 1003 parts water
4.0 parts by weight Silicone L5
32 (@ Nippon Unicar) t, s 31 parts Kaolizer 421 (■ Kako) 1.0 parts by weight Stanus octoate o, oi; parts by weight Coronate T-80 (
Nippon Polyurethane Co., Ltd. Trilenediine/Anate)
R = 1.05 The temperature of each liquid used in the above formulation is 20
℃, add one polyethylene chloride solution and mix at 400 rpm with a stirrer (T, Homodisper SL type manufactured by Tokushu Kika Kogyo Co., Ltd.), 250 x 250
Quickly transfer to an open top box at 250 am.
Free foaming was performed. Mold temperature is 20°C0 Heat resistance evaluation FiJ of the obtained flexible polyurethane foam
Moist heat aging test of ISK”-6401-1980 (reference)
The tensile strength was measured after 6 hours, 9 hours, 12 hours, and 24 hours using the method described above, and was compared with the tensile strength of the foam before the test.

In addition, JISK-6401 also applies to pressed pongee Mizuku Hisumi.
It was measured by the 1980 compression permanent strain experimental method and compared with a comparative example.

Table IK shows the results of measuring the physical properties of this flexible polyurethane foam.

Comparative Example 1 Adipic acid 2328. ! TI% 1.6-hexanediol 23689 and tetra-n-butyl titanium 40rRg as an esterification catalyst were charged, and the reaction was carried out in the same manner as in the production of the copolyester polyol in Example 1 to obtain a number average molecular weight of 1000. A polyester polyol having an average functional group number of 2.0 was obtained. This polyester polyol was solid at room temperature, making it impossible to produce flexible polyurethane foam.

Comparative Example 2 Example 1 was prepared using a copolyester polyol (number average molecular weight 2520, average functional group number 2.65) made from adipic acid, trimethylolpropane, and diethylene glycol (number average molecular weight 2520, average functional group number 2.65), which is mainly used for producing flexible polyurethane foams. Similarly, flexible polyurethane foam was produced by free foaming. The physical properties were measured in the same manner as in Example 1. The results of this envy are shown in Table 11/C.

Example 2 Mixed dicarboxylic acid [302
6g and diethylene glycol 1347. @(75molφ) 3-)f-1,5-pentanodiol 500
．． total amount of mixed diglycol and trimethylolpropane of 2100. Copolyester polyol 2 having a number average molecular weight of 2970, an average number of functional groups of 3.2, an OHV of 60.5, and a molecular weight of 0.4 was synthesized in the same manner as in Example 1 except that @ was used.

Using copolyester polyol 2 as raw material, Example 1
A flexible polyurethane foam was produced in the same manner.

The physical properties were measured in the same manner as in Example 1. The warping results are shown in Table 1.

Example 3 3155 g of sebacic acid and 120 g of diethylene glycol
6 g (over 75 moles) and 448 1,6-hexanediol
Example 1 was carried out in the same manner as in Example 1 except that the total amount of mixed glycol and trimethylolpropane (25 mol %) was 1907.9. The number average molecular weight was 3120 and the average number of functional groups was 3.3.0) (V .4, AVo, 4 ordinary m-t'
A viscous-like saw polyester polyol 3 was synthesized.

This copolyester polyol 3 was used as an i material, and Example 1
Kk quality polyurethane foam was produced in the same manner as above. this?
The lability was measured by a method similar to Example 1 and 111IJ. The results are shown in Table IK.

Example 4 3156 g of sebacic acid and 120 g of diethylene glycol
The total amount of mixed diol of 5 g (75 mol %) and 3-methyl-1,5-pentanediol 447 g (25 mol %) and trimethylolpropane was 1905. The number average molecular weight was 3120 in the same manner as in Example 1 except that jil was used.
, average functional group number 3.3, OHV 59.4, AV 0.
417) Copolyester polyol 4, which is sticky at room temperature, was synthesized.

Using this copolyester polyol 4 as a raw material, a flexible polyurethane foam was produced in the same manner as in Example 1.

The physical properties were measured in the same manner as in Example 1. The results are shown in Table IK.

Example 5 The total charged amount of sebacic acid 3127 fl, mixed glycol of diethylene glycol 79i (50 mol%) and 3-methyl-1,5-pe/tanediol 884.9 (50 mol%), and trimethylolpropane was 1930 g. The same procedure as in Example 1 was used except that the mixture was viscous at room temperature, average molecular weight 2960, average number of functional groups 32, OHV 60.6,
A copolyester polyol 5 with AVo, 3 was prepared.

Example 1 using this copolyester polyol 5 as a raw material
A flexible polyurethane foam was produced in the same manner as above. The physical properties were measured in the same manner as in Example 1. Table 1 shows the results.
Shown below.

Example 6 Sehashi7 acid 1564. jil (50 mol%)
(A mixture of 1,456 g (50 mol φ) of
9 with diethylene glycol 796J (50 mol%) and 3
-Methyl-1,5-be/tanediol 886.9 (50
It was made in the same manner as in Example 1, except that the total amount of mixed glycol (mol%) and trimethylolpropane was 1935 g, and was sticky at room temperature, average molecular weight 2980, average functional group number 3, 2.0 HV 60.3, AVo, A copolyester polyol 6 of Example 5 was prepared.

Example 1 using this copolyester polyol 6 as a raw material
A flexible polyurethane foam was produced in the same manner as above. The physical properties were determined in the same manner as in Example 1. The results are shown in Table IK.

Example 7 Sebacin lII 1758g (50 mol%) and Ajibia r
A mixture of 3029p of R1271g (so mol%) and a mixture of diethylene glycol 131711 (75mol%) and 489g (25mol%) of 3-methyl-1,5-pentanediol was added to a total amount of 2071/l. A copolyester polyol 7 having a number average molecular weight of 3540, an average number of functional groups of 3.8.0, an AVo of 4, and an AVo of 4 was produced in the same manner as in Example 1, except that the copolyester polyol 7 was viscous at room temperature.

Example 1 using Conoco Polyester Polyol 7 as a raw material
A flexible polyurethane foam was produced in the same manner as above. The physical properties were measured in the same manner as in Example 1. Table 1 shows the results.
Shown below.

Notes on Table 1 below: Measurement atmosphere: 20″Q 50%RH 1) 25% ILD: J INK 6401-198
According to the hardness test method of 0. The test piece is 250 x 2
50 x 50 FRFI! It is.

2) 50% compression set: J ISK 6401-19
80 compression set test method. The test piece is 5
It is 5X55X50mm.

3) 80% compression set: JISK 6401-198
0 compression set test method. Nasi test piece is 55
The size is 55 x 50 m.

4) TB (tensile strength): test piece is 20 x 120 x
It was carried out under the conditions of 10 mm and a pulling speed K of 300"n1 minute. The measuring equipment was A, UTOG FLAPH 15-50.
00 (manufactured by Shimadzu Corporation).

Humid heat test: “Reference” of JISK 6401-1980
According to the moist heat aging test method. And 'r,, t at that time
- Measured.

5) exterior 6) How it feels when you press the foam with your finger In the table, ◎: good, O: good, △: fair, ×: bad.

Claims (1)

[Claims] When obtaining a flexible polyurethane foam from an organic diisocyanate, a polyester polyol, a blowing agent, a catalyst, and a surfactant, the polyester polyol contains sebacic acid or a mixture of sebacic acid and another dicarboxylic acid as an acid component. and, as a polyhydric alcohol component, (a) trimethylolpropane, (b) diethylene glycol, and (c) 1,6-
Hexanediol and/or 3-methyl-1,5-pentanediol in a molar ratio of (b) and (c) of 40 to 80
Mol%: The number average molecular weight obtained by reacting at 60 to 20 mol% is 1000 to 4000, and the number average number of functional groups is 2.
A moisture and heat resistant flexible polyurethane foam characterized by having a polyurethane foam having a polyurethane content of 2 to 4.0.