JP2885896B2 - Urethane foam catalyst - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention relates to a urethane foam catalyst, particularly a catalyst material remaining in a product after foam molding is transferred to a surface layer to form a sheet material for covering a foam. The present invention relates to a urethane foam catalyst that does not discolor or deteriorate to lower the quality of a product.

(Prior Art) In recent years, there has been an increasing demand for molded products in which the surface of a urethane foam is coated with polyvinyl chloride or a polyurethane elastomer, mainly for vehicle components. In particular, polyvinyl chloride has excellent moldability, high physical strength and low cost, and is expected to expand its use in a wide range of applications.However, the catalyst for foaming residual urethane reacts with polyvinyl chloride. There is a problem that the molded product is discolored or deteriorated.

(Problems to be Solved by the Invention) For example, 1,4-diazabicyclo (2,2,2) octane as a main catalyst and N as a cocatalyst, which have been conventionally used for producing polyurethane foams and molded articles thereof, have been proposed. Volatile tertiary amines such as -methyl or N-ethylmorpholine, N, N, N ', N'-tetramethylethylenediamine and triethylamine have a strong tendency, and 1,4-diazabicyclo (2 , 2,2) Notable in octane.

On the other hand, the volatile tertiary amine as a co-catalyst is effective in forming the skin layer of urethane molded products, but produces a bad smell and amine vapor during the manufacturing process and demolding, and causes chronic or acute poisoning of eyes and human bodies. The occurrence of symptoms is a problem.

As a catalyst which becomes non-migratory by reacting with an NCO group, a polyamine compound represented by the above general formula (1) is disclosed in JP-A-46-48.
Although described in Japanese Patent No. 46, this has the disadvantage of being volatile and offensive odor.

Further, JP-A-59-191734 discloses a carbonate of the above-mentioned polyamine compound as a low-odor, non-migrating catalyst. However, as shown in Examples described later, the processing time (particularly rise time) However, there is a problem that a considerable amount of catalyst is required to shorten the time and the tack-free time to increase the production efficiency.

(Means for Solving the Problems) The present inventors have found that the catalyst remaining in the product does not bleed even after the foaming is completed, and that the vinyl chloride sheet covering the surface layer and the foam is not discolored, and that the odor is further reduced. As a result of various studies to develop an amine catalyst with low volatility,
The present invention has been reached.

That is, the urethane foam catalyst according to the present invention has a general formula (Wherein, R ₁ and R ₂ are the same or different alkyl groups each having 1 to 4 carbon atoms, and R ₃ is an alkylene group having 2 to 12 carbon atoms). ) And the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as above) and the alkanolamine compound (B).

 Hereinafter, details of the present invention will be described.

The catalyst for urethane foam according to the present invention comprises a combination of two components, a carbon salt (A) of a polyamine compound represented by the general formula (1) and an alkanolamine compound (B) represented by the general formula (2). Here, R ₁ , R ₂ and R ₃ in the general formulas (1) and (2) have the same meaning.

That is, R ₁ and R ₂ are the same or different alkyl groups having 1 to 4 carbon atoms, and specifically, methyl,
Ethyl, n- or iso-propyl, n- or iso-
A linear or branched alkyl group such as butyl is exemplified, and among these, a methyl group is most preferable from the viewpoint of catalytic activity.

R ₃ is an alkylene group having 2 to 12 carbon atoms, specifically, linear or branched such as ethylene, n- or iso-propylene, n- or iso-butylene, tetramethylene, hexamethylene, decamethylene and the like. Of these, ethylene, n-propylene and n-butylene groups are preferred from the viewpoint of catalytic activity.

Examples of the polyamine compound represented by the general formula (1) include dimethylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, diethylaminopropylamine, dibutylaminoethylamine, dimethylaminooctylamine, and dipropylaminopropylamine.

Among these polyamine compound carbon salts (A), particularly preferred compounds from the viewpoint of catalytic activity include dimethylaminopropylamine carbon salts and dimethylaminoethylamine carbon salts.

The alkanolamine compound (B) represented by the general formula (2) includes N, N-dimethyl-N ', N'-di (2-
Hydroxypropyl) -1,3-propylenediamine, N, N
-Dimethyl-N ', N'-di (2-hydroxypropyl)
-1,2-ethylenediamine, N, N-diethyl-N ', N'-
Di (2-hydroxypropyl) -1,3-propylenediamine, N, N-dibutyl-N ', N'-di (2-hydroxypropyl) -1,2-ethylenediyne, N, N-dimethyl-
N ', N'-di (2-hydroxypropyl) -1,8-octylenediamine, N, N-dipropyl-N', N'-di (2-hydroxypropyl) -1,3-propylenediamine and the like Is exemplified. Among them, preferred compounds from the viewpoint of catalytic activity are N, N-dimethyl-N ', N'-di (2-hydroxypropyl) -1,3-propylenediamine, N, N-
Dimethyl-N ', N'-di (2-hydroxypropyl)-
1,2-ethylenediamine and the like.

The compounding ratio of the carbon salt (A) of the polyamine compound and the alkanolamine compound (B) in the catalyst of the present invention is from 10:90 to 90:10, preferably from 20:80 to 80:20 by weight ratio. When the compounding ratio of the carbon salt (A) or the alkanolamine compound (B) is 10 or less, the processing time such as rise time and tack-free time becomes longer as described later, and as a result, The molding time becomes longer and the production efficiency decreases. In this case, if the total amount of the above (A) and (B) is increased, the processing time is shortened and the demolding time is shortened, but the discoloration of the vinyl chloride coating material is undesirably increased.

As described in JP-A-59-191743, the carbon salt of the polyamine compound (A) may be prepared by contacting the corresponding polyamine with carbon dioxide in the presence of water. Compound (B) can also be easily synthesized by adding propylene oxide to the corresponding polyamine.

The urethanization reaction to which the catalyst of the present invention is applied is a reaction between a polyisocyanate and a polyfunctional active hydrogen compound. Examples of the polyisocyanate used here include aromatic polyisocyanates such as tolylene diisocyanate and diphenylmethane diisocyanate, and hexaisocyanate. Conventionally known compounds such as methylene diisocyanate, aliphatic polyisocyanates such as isophorone diisocyanate, modified products such as partial carbodiimides or isocyanurates thereof, and free isocyanate group-containing prepolymers obtained by reacting these with polyfunctional active hydrogen compounds. These can be used alone or as a combination of two or more.

On the other hand, examples of the polyfunctional active hydrogen compound include water, low molecular weight polyols, high molecular weight polyols, polyamines, and compounds having two or more phenolic hydroxyl groups, which may be used alone or in combination of two or more. Can be.

Examples of the low-molecular polyol include amine-based low-molecular polyols such as triethanolamine and diethanolamine and chips such as ethylene glycol, diethylene glycol, butanediol, trimethylolpropane, glycerin, and p-bis (2-hydroxyethyl) phenylene ether. Low-molecular-weight polyols having no halogens;
The polymer polyol, for example, ethylene oxide, alkylene oxides such as propylene oxide, and water, ethylene glycol, propylene glycol, glycerin, trimethylolpropane, triethanolamine, pentaerythritol, sorbitol, low molecular polyols such as sucrose, , Ethylenediamine, diethylenetriamine, tolylenediamine, xylylenediamine, piperazine, N-aminoalkylpiperazine, N, N
-A polyether polyol having a structure to which a polyamine such as dimethylaminoalkylamine and cyclohexylenediamine is added, and reacting the polyether polyol with an ethylenically unsaturated monomer such as acrylonitrile, styrene, methyl methacrylate, and butadiene. Polymer polyol (see US Pat. No. 3,383,351)
And polyester polyols obtained by the reaction of polycarboxylic acids such as succinic acid, maleic acid, sebacic acid, adipic acid, fumaric acid, phthalic acid, and dimer acid with the above low-molecular polyols; and polyamines such as tolylenediamine, Known compounds such as diamine, diaminodiphenylmethane, methylenebis-o-chloroaniline, and mono (or poly) lower alkylated products of these polyamines may be used alone or in combination of two or more. Can be.

Further, a compound having two or more phenolic hydroxyl groups includes a resol type initial condensate obtained by condensing phenols with an excess of aldehydes in the presence of an alkali catalyst, and a benzylic type initial condensate obtained by reacting in a non-aqueous system when synthesizing the same. Examples include condensates and novolak-type precondensates obtained by reacting aldehydes with excess phenols in the presence of an acid catalyst. The molecular weight of these precondensates is preferably from 200 to 10,000. Here, phenols mean those in which one or more carbon atoms forming a benzene ring are directly bonded to a hydroxyl group, and include those having other substituents in the same structure. Representative compounds include phenol, cresol, bisphenol A, resorcinol, and the like. Although it is not particularly limited as aldehydes,
Examples include formaldehyde and paraformaldehyde.

Further, a foaming agent is used in combination with this reaction. Examples of the foaming agent include halogenated hydrocarbons such as chlorofluorocarbon and methylene chloride, low-boiling hydrocarbons such as butane, pentane and hexane, water, air, and nitrogen. And organic blowing agents such as amine carbonates such as formic acid derivatives, cyanoacetic acid derivatives, and butylamine carbonate, malonic acid derivatives, and azo compounds such as azodicarboxylic acid amide.

The catalyst comprising the carbonate (A) of the polyamine compound and the alkanolamine compound (B) in the present invention can be used alone for producing soft, semi-rigid and rigid urethane foams. It is useful for producing a semi-rigid urethane foam, a molded product thereof, and a molded product provided with a coating material.

The above catalyst in the present invention can also be used in combination with other known catalysts described below, if necessary. That is, these catalysts include, for example, polyamine compounds represented by the general formula (1) such as dimethylaminopropylamine,
1,4-diazabicyclo (2,2,2) octane, 1,3,5-tris (3-dimethylaminopropyl) hexahydro-s-
Triazine, N, N, N ', N'-tetramethylhexamethylenediamine, N, N, N-tris (dimethylaminopropyl) amine, N-methyl-N, N-bis (dimethylaminopropyl) amine, N- Examples thereof include amine catalysts such as methyldicyclohexylamine, 1,2-dimethylimidazole, and 1,8-diazabicyclo (5,4,0) undecene-7.

On the other hand, the catalyst of the present invention can be used in combination with a metal catalyst such as stannas octoate, dibutyltin dilaurate, and mercaptan tin.

When these catalysts are used in combination with the catalyst of the present invention, it is necessary to limit these catalysts to usually 30%, preferably 20% or less, based on the total weight of the catalyst, in order to achieve the object of the present invention.

In the production of the urethane foam using the catalyst of the present invention, a crosslinking agent, an emulsifier, a stabilizer, a surfactant as a cell regulator, a filler, a coloring agent, an antioxidant, a flame retardant, and the like are used as needed. You can also.

The total amount of the catalyst of the present invention is the above-mentioned polyfunctional active hydrogen compound.
Usually 0.01 to 5 parts by weight, preferably 0.1 to 100 parts by weight
~ 2 parts by weight. If it is less than 0.01 part by weight, the catalytic activity is low and it takes too much time to complete the reaction, and if it exceeds 5 parts by weight, the physical properties of the foam, especially the compressive strength,
Discoloration of polyvinyl chloride as a coating material also increases.

The production of the urethane foam can be carried out in the same manner as in the prior art, and any one-shot method or prepolymer method can be applied. Further, the present invention can be applied to the production of elastomers and sealants, and the production conditions such as the types of main raw materials and auxiliaries, their blending ratio, and the amount of catalyst added may be the same as those in the past.

As described above, the catalyst according to the present invention is useful for producing a molded article in which a urethane foam molded article is coated with a sheet-shaped material, particularly a sheet-shaped material made of a vinyl chloride resin. Discoloration and deterioration can be prevented beforehand.

An example of the production of this molded product will be described in more detail. First, an isocyanate component is a liquid B and the other components are a liquid A, and each liquid is filled in both tanks A and B of the foaming machine. On the other hand, a sheet material such as a vinyl chloride sheet is set in the mold in advance by vacuum forming,
Alternatively, a film of a sheet material is formed on the inner surface of the mold by a so-called slash molding method in which a plastic sol such as polyvinyl chloride is molded in a mold by heating, and the two liquids A and B are mixed by a mixing head. Is injected into a mold and foamed.

The catalyst according to the present invention is an object other than these, for example, molding by RIM method, molding by open mold, production of vacuum molding, etc., further cold or hot cure, slab method, on-site construction, spray method, injection, It can be applied to various methods such as coating and impregnation.

EXAMPLES Hereinafter, specific examples of the present invention will be described, but the present invention is not limited thereto.

Example 1 (Comparison by foaming test of type of catalyst) 100 parts by weight of Sannics FA-703 (manufactured by Sanyo Chemical Industries, Ltd., glycerin-propylene oxide / ethylene oxide adduct, OH value: about 34), triethanolamine
4.0 parts by weight, 2.5 parts by weight of water and Millionate MR-200
(Nippon Polyurethane Industry Co., Ltd., crude diphenylmethane diisocyanate [hereinafter referred to as crude MDI], NCO%: about 31
%) 58.9 parts by weight (105 as NCO index)
60 of semi-rigid urethane formulation with the type and amount of catalyst shown in
g, raw materials other than the crude MDI were first weighed and mixed uniformly in a 500 ml capacity paper cup, and the temperature was adjusted to 25.0 ± 0.5 ° C. Then, the crude MDI at the same temperature was added and immediately stirred at high speed for 7 seconds. A urethane foam was obtained in the paper cup. During this foaming process, the processing time (cream time (ct), rise time (rt), tack-free time (tft)) and foam height (foam height) were measured, and the results are shown in Table 1. Was.

In addition, the code | symbol in the item of the catalyst in a table | surface means the following.

I: Dimethylaminopropylamine acidic carbonate (70
%), Free dimethylaminopropylamine (10%),
Mixture of water (20%) (application of the invention).

II: N, N-dimethyl-N ', N'-di (2-hydroxypropyl) -1,3-propylenediamine, gold amine value: 587
(Product of the present invention).

III: 1.4-diazabicyclo (2,2,2) octane containing 33% dipropylene glycol solution (control).

IV: triethylamine (control).

V: N, N, N'-trimethyl-N '-(2-hydroxyethyl) -1,2-ethylenediamine (control).

As can be seen from Table 1, the catalyst charge was 1.0, 0.8 and 0.
In any case of 6 parts by weight, when the catalysts I and II of the present invention were combined (3/7 to 7/3 as I / II), the catalyst I or II was used alone ( 10 as I / II
Ct, rt and tft are shorter than / 0 or 0/10).
That is, according to this, in order to obtain a certain rt or tft, the total use amount of the catalyst can be reduced by the mixed use of I / II which exerts a synergistic effect than by the use of each of I and II alone. As a result, discoloration of the coating material can be prevented. Also, the foam height tends to increase.

Of the control catalysts, III has the same activity as the product of the present invention despite having a high activity and containing 33%.
Although it shows thyme, the discoloration of vinyl chloride as a coating material is remarkable. The same is true for control catalyst V. The control catalyst IV requires 1.5 times the amount of the catalyst compared to the I / II mixed catalyst of the product of the present invention, and furthermore, the odor becomes a problem.

Example 2 (Discoloration test on an integrally molded article using a polyvinyl chloride sheet as a coating material) In the foaming formulation described in Example 1, the amount of the catalyst used was adjusted so that the rise time was 90 seconds as shown in Table 2. Was adjusted. However, in Experiments Nos. 22 and 23, the amount of each of the catalysts I and II was 2.3 parts by weight, and the relationship between the amount of the catalyst and the discoloration of the polyvinyl chloride sheet was examined.

From this foaming formula, 120 g was weighed into a 500 ml capacity paper cup, mixed uniformly, and rapidly stirred at 25.0 ± 0.5 ° C. for 10 seconds,
Put this in a mold of size 20.0 × 20.0 × 1.0cm (1 in the mold)
A 7cm square polyvinyl chloride sheet is stuck and release agent bond wax URT-35T is applied, mold temperature 40.0 ±
(Adjusted to 2.0 ° C.), and after 7 minutes, it was released from the mold to obtain an integral foam molded body whose surface was covered with a polyvinyl chloride sheet. The overall density of the urethane foam excluding the polyvinyl chloride sheet was 0.23 to 0.24.

This polyvinyl chloride sheet-integrated foam molding is wrapped in aluminum foil and heat-treated in an oven at 110 ° C.
The discoloration degree (ΔE *) of the polyvinyl chloride sheet at every 0 and 400 hours was measured using a multi-source spectrophotometer (light source C, visual field 2 degrees,
(Diameter 15 mm circle) and determined by the following formula.

L: brightness, a: reddish, b: yellowish, Δ: rate of change As can be seen from Table 2, Experiment No. 19 had the least degree of discoloration of the polyvinyl chloride sheet, in contrast to Experiment No. 17, and a result superior to Experiment No. 18 was obtained. In Experiments Nos. 20 and 21 in which I and II catalysts were used alone, the amount of catalyst required to make the rise time 90 seconds was 1.5 times that in Experiment No. 19 in which mixed use was used. Therefore, the degree of discoloration of the polyvinyl chloride sheet also increased.

It should be noted that a comparison between Experiments Nos. 20 to 21 and Nos. 22 to 23 shows that the degree of discoloration of the polyvinyl chloride sheet increases as the amount of the catalyst used increases.

(Effect of the Invention) According to the catalyst of the present invention comprising a combination of the two components of the carbonate (A) of the polyamine compound and the alkanolamine compound (B), the catalytic activity is greatly increased by the synergistic effect of both components. Therefore, the total amount of the catalyst used is significantly reduced, and as a result, discoloration of the polyvinyl chloride in the surface layer can be suppressed.

The carbonate (A) of the polyamine compound contains NCO in its molecule.
It has an elementary-reactive primary amine group and the alkanolamine compound (B) also has two NCO-reactive hydroxyl groups in one molecule, so it reacts with the organic polyisocyanate and chemically bonds to the polymer skeleton I do. As a result, after the foaming is completed, the catalyst does not bleed and come into contact with the polyvinyl chloride on the surface layer to cause no discoloration.

Due to the NCO group reactivity described above, the catalyst of the present invention has no odor at the time of demolding.

Since the carbonate (A) of the polyamine compound is a salt with carbonic acid, and the alkanolamine compound (B) is a high-boiling compound, each of them has almost no amine odor.

Due to the above, the working environment during the manufacturing process is improved.

It is extremely useful for producing urethane foam molded articles and sheet materials, particularly urethane foam molded articles coated with a sheet material made of polyvinyl chloride resin.

Continuation of the front page (56) References JP-A-59-191743 (JP, A) JP-A-53-126099 (JP, A) JP-A 64-4613 (JP, A) JP-A-2-70718 (JP) JP-A-63-265909 (JP, A) JP-A-63-90529 (JP, A) JP-A-3-255120 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) C08G 18/00-18/87 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] (1) General formula (Wherein R ₁ and R ₂ are the same or different alkyl groups having 1 to 4 carbon atoms, and R ₃ is an alkylene group having 2 to 12 carbon atoms). ) And the general formula (Wherein R ₁ , R ₂ and R ₃ are the same as described above), and a alkanolamine compound (B). 2. A urethane foam composition comprising the catalyst according to claim 1 and an organic polyisocyanate, a polyfunctional active hydrogen compound and a blowing agent.