JPH0725861B2 - Amine catalyst for polyurethane - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel tertiary amine compound useful as a catalyst for producing polyurethanes such as soft, hard and elastomers. More specifically, the present invention relates to a novel catalyst having a homopiperazine skeleton in the molecule, which is odorless and has excellent curing performance, for producing polyurethane.

[Prior Art] Organometallic catalysts and tertiary amine catalysts have hitherto been used as catalysts for polyurethane production, and it is widely known that tertiary amine compounds can be excellent catalysts for polyurethane production. There is. However, the substances collectively referred to as tertiary amine compounds behave differently as catalysts for polyurethane due to the difference in their chemical structures. In other words, not all tertiary amine compounds are industrially useful as polyurethane catalysts. Among the tertiary amine compounds,
As a tertiary amine catalyst for industrially used polyurethane, the following triethylenediamine, N, N, N ', N',
N ″ -pentamethyldiethylenetriamine, N, N, N ′, N ′
-Tetramethylhexamethylenediamine, N-methyl-
N '-(2-dimethylamino) ethylpiperazine, N, N'
-Dimethylpiperazine, N-methylmorpholine, N-ethylmorpholine, N, N'-dimethylethanolamine and the like can be exemplified. These tertiary amines can be classified into strong activity, moderate activity, and weak activity depending on the strength of activity. Of these, the weak catalyst has an important effect that greatly affects the curing rate of polyurethane and the physical properties of foam. Such weak catalysts include N-methylmorpholine, N-ethylmorpholine,
N, N'-dimethylpiperazine, or N, N'-dimethylethanolamine, N- as a compound having an OH group in the molecule
Examples thereof include methyl-N '-(2-dimethylamino) ethylpiperazine.

[Problems to be solved by the invention]

However, hitherto known weak amine catalysts for polyurethane have various problems. Already, N-methylmorpholine and N-ethylmorpholine have an extremely strong irritating odor, which deteriorates the working environment due to the bad odor of the foaming process and leaves the polyurethane product itself with a bad odor. In addition, dimethylethanolamine has a high volatility and thus has a bad odor.Since it has an OH group, it reacts with isocyanate and loses its activity significantly. There is a problem that the mold time cannot be shortened.

[Means for solving problems]

The present inventors have diligently studied to solve various problems of known weak catalysts. As a result, dimethylhomopiperazine (hereinafter abbreviated as DMHMP) having a homopiperazine skeleton has desirable activity as a weak catalyst, has less odor, and has an excellent effect as a catalyst for accelerating the curing rate of polyurethane foam. The heading has arrived at the present invention.

Hereinafter, the present invention will be described in detail.

The amine catalyst for polyurethane production of the present invention has the following formula It is a compound represented by and is a substance usually called N, N′-dimethylhomopiperazine.

Examples of the industrial production method of DMHMP of the present invention include J.Org.C.
N-induced by the reaction described in hem., 26, 4135 (1961).
It can be easily produced from methylhomopiperazine or homopiperazine. As the method of methylation, for example, the Leukart-Warach reaction described in US Pat. No. 4026840 or the reductive methylation reaction described in West German Patent No. 2618580 can be used.

In addition, it is also produced by the reaction of N, N'-dimethylpropanediamine and dichloroethane, but the production method is not particularly limited.

The DMHMP of the present invention can be used as a co-catalyst for polyurethane in combination with other tertiary amine compounds and organometallic compounds. As other tertiary amine compounds, for example, triethylamine, N, N-dimethylcyclohexylamine, N, N,
N ', N'-tetramethylethylenediamine, N, N, N', N '
-Tetramethylpropylenediamine, N, N, N ', N'-Tetramethylhexanemethylenediamine, N, N, N', N ", N"-
Pentamethyldiethylenetriamine, N, N, N ′, N ″, N ″ −
Pentamethyl- (3-aminopropyl) ethylenediamine, N, N, N ', N ", N" -pentamethyldipropylenetriamine, N, N, N', N'-tetramethylguanidine, triethylenediamine, N, N ' -Dimethylpiperazine, N-methylmorpholine, N-ethylmorpholine, N- (N ', N'-dimethylaminoethyl) morpholine, 1,2-dimethylimidazole, 3- (dimethylamino) propylimidazole, N, N-
Dimethylethanolamine, dimethylaminoethoxyethanol, N, N, N'-trimethylaminoethylethanolamine, 1,3-bis (N, N-dimethylamino) -2-propanol, N-methyl-N '-(2- Examples of known tertiary amine compounds include dimethylaminoethyl) piperazine and bis (2-dimethylaminoethyl) ether.
Preferably triethylenediamine and / or bis-
(2-dimethylaminoethyl) ether. Examples of the organometallic compound include stannous octoate, dibutyltin dilaurate, dibutyltin diacetate, dibutyltin oxide, dioctyltin dilaurate, and other organotin compounds, with stanas octoate or dibutyltin dilaurate being preferred. .

The amount of catalyst usually used in the production of polyurethane is not particularly limited. Generally, it is 0.01 to 10 parts per 100 parts of polyol. It is preferably 0.05 to 5 parts. When it is less than 0.01, the catalyst activity is low and it takes a long time to complete the reaction.

The polyisocyanates which can be used for producing polyurethane foams with the catalysts according to the invention may be known polyisocyanates, for example toluene diisocyanate, diphenylmethane-4,4'-diisocyanate and free isocyanate-containing compounds by the reaction of these with polyols. Prepolymers may be mentioned. As described above, the type of isocyanate is not limited.

As the polyol that can be used with the catalyst of the present invention, known polyester polyols, polyether polyols, polymer polyols and mixtures thereof can be used. Known polyester polyols usually include compounds derived from dibasic acids and polyhydric alcohols. Known polyols include, for example, polyether polyols and amine compounds such as ammonia and aliphatic amine compounds obtained by addition reaction of polyhydric alcohols such as glycol, glycerin, pentaerythritol, trimethylolpropane and sucrose with ethylene oxide or propylene oxide, Amine polyols derived by adding ethylene oxide or propylene oxide from an aromatic amine compound are included. Known polymer polyols include polymer polyols obtained by reacting the polyether polyol with ethylenically unsaturated monomers such as butadiene, acrylonitrile and styrene in the presence of a radical polymerization catalyst.

As described above, any polyol widely used for polyurethane production can be used and is not particularly limited.

When using the catalyst of the present invention, a crosslinking agent or a chain extender can be added if necessary. As the crosslinking agent or the chain extender, a low molecular weight polyhydric alcohol, for example,
Ethylene glycol, 1,4-butanediol, glycerin, low molecular weight amine polyols such as diethanolamine, triethanolamine and polyamines such as
Ethylenediamine, xyleranediamine, methylenebisorthochloroaniline, etc. are used.

When using the catalyst of the present invention, if necessary, halogenated methanes such as Freon 11 and Freon 1 as a blowing agent.
2, methylene chloride and water can be used.

If necessary, an organic silicon compound colorant, a flame retardant, and other known additives can be used as the surfactant. The types and amounts of these additives can be sufficiently used within the range generally used unless they deviate from known formats and procedures.

〔The invention's effect〕

The amine catalyst for polyurethane of the present invention has extremely low odor compared with weak catalysts such as N, N′-dimethylpiperazine, N-methylmorpholine, N-ethylmorpholine and dimethylethanolamine, and has a significantly high working environment in the polyurethane production process. It has an advantage that it is improved and does not leave a bad odor on the production foam itself, and its industrial value is extremely large.
Further, it has a comparatively high catalytic activity and has an economical advantage that the addition amount is small.

Furthermore, since the curing speed of the polyurethane foam is increased, the productivity of the foam can be improved.

〔Example〕

Hereinafter, the present invention will be described based on examples, but the present invention is not limited to these examples.

Example 1 and Comparative Examples 1 to 5 Polyurethane foaming was performed under the following composition and foaming conditions, and the physical properties of the resulting foam were measured. The results obtained are shown in Table 1.

(B) Formulation Polyol ¹⁾ 100 parts by weight Water 1.5 Silicon F-317 ²⁾ 1.5 Freon R-11 35 Catalyst ³⁾ Change Isocyanate ⁴⁾ 133 (Index 110) 1) Sucrose-aromatic amine manufactured by Takeda Pharmaceutical Co., Ltd. -Based polyether polyol (OHV = 400 mgKOH / g) 2) Shin-Etsu Chemical Co., Ltd. silicon surfactant 3) TEDA-L33 using the catalyst shown below as a comparative example; Tosoh Corporation triethylenediamine and dipropylene glycol 67% Liquid product containing DMP; N, N'-dimethylpiperazine NMM; N-methylmorpholine NEM; N-ethylmorpholine DMEA; N, N-dimethylethanolamine 4) Crude MDI manufactured by Nippon Polyurethane Co., Ltd. (NCO content = 31.0
%) (B) Foaming conditions Raw material temperature 20 ± 1 ° C Stirring speed 6000rpm (5 seconds) Mold temperature 50 ° C (C) Measurement item 1) Foam density Foamed in a polyethylene beaker with a volume of 2l and the center of foam is 7cm The measurement was performed by cutting x7 cm × 6 cm.

2) Curability of foam The foaming raw material is adjusted so that the packing rate is a predetermined amount, and foaming is performed in the mold. Quickly demold for a period of time and measure foam blisters. The evaluation is expressed as follows.

◯: Small Δ: Medium ×: Large 3) Odor The odor of the catalyst used in the foaming test was expressed as follows.

◯: Almost no odor △: Odor ×: Strong odor Example 2 and Comparative Examples 6 to 10 The following results were obtained in the same manner as in Example 1, and the results obtained are shown in Table 2.

(A) Formulation Polyol I ⁵⁾ 60 parts by weight Polyol II ⁶⁾ 40 Water 2.7 Recon SRX-274C ⁷⁾ 2.0 Catalyst ⁸⁾ Change Isocyanate ⁹⁾ 36 (Index 105) 1) Sanyo Kasei Kogyo Co., Ltd. Polyol (OHV = 34mgKOH / g) 2) Polymer polyol manufactured by Sanyo Chemical Co., Ltd. (OHV = 28mgK)
OH / g) 3) Silicone surfactant manufactured by Toray Silicone Co., Ltd. 4) An amine catalyst was prepared with the mixing number shown in Table 2.

5) Crude MDI made by Nippon Polyurethane Industry (NCO content = 31.0
%) (B) Foaming conditions Same as in Example 1 (C) Measurement items 1) Foam density Same as in Example 1 2) Curability Foam Stickiness of foam at demolding and foam hardness are expressed by the following evaluation. It was

◯: Good Δ: Medium ×: Poor 3) Odor Same as Example 1.

Claims (1)

[Claims] 1. The following equation An amine catalyst for producing a polyurethane represented by: