JPS63265909A - Catalyst for manufacture of polyurethane - Google Patents

Abstract

PURPOSE:To provide a catalyst for the manufacture of a polyurethane having a high activity and a less odor which does not migrate to the surface of a molded article therefrom, comprising a specific compound having a dimethylamine group and a plurality of hydroxyl group in the molecule. CONSTITUTION:A compound of the formula (wherein m+n is 1-6) is used as a catalyst for the manufacture of a polyurethane. An example of the compound represented by the formula is an adduct of ethylene oxide (2mol.) to dimethylaminopropylamine which can be easily prepared by adding ethylene oxide to dimethylaminopropylamine. It is suitable that the catalyst comprising the compound of the formula is used in an amount of about 0.01-10pts.wt. per 100pts.wt. polyol which is used for the manufacture of the polyurethane. Since this catalyst reacts with the isocyanate group to be incorparated into the polyurethane molecule, it does not migrate to the resin surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a catalyst used in the production of polyurethanes such as soft, hard, semi-hard or elastomers. More specifically, it relates to a novel catalyst for producing polyurethane that has two dimethylamino groups and a hydroxyl group in its molecule, has extremely low odor, acts as a chain extender in polyurethane resin, and improves the physical properties of the polymer. It is.

[Conventional technology and problems]

Conventionally, tin-based and iron-based organic metals and tertiary amines have been used as catalysts for producing polyurethane, with tertiary amines being particularly preferred.

For example, compounds such as N-, methylmorpholine, triethylenediamine, tetramethylhexamethylenediamine, pentamethyldiethylenetriamine, and dimethylcyclohexylamine are used as catalysts for polyurethane production.

However, the catalysts for producing polyurethane that have been developed so far have various problems. That is, N-methylmorpholine has an extremely strong pungent odor, and
When polyurethane is manufactured using these compounds,
Due to the low boiling point of N-methylmorpholine, the product has a pungent odor from these compounds even after manufacture. Furthermore, when polyurethane is produced using this compound, the urethane catalyst remaining in the product migrates to other compounds that come into contact with the polyurethane (for example, PvC sheets), causing discoloration, rendering the product without commercial value. There are often cases where this is turned into something.

Furthermore, regarding catalysts that are considered to be non-migration type in polyurethane resin, Japanese Patent Laid-Open No. 46-4846 discloses
The following formula (2) (In the above formula, each R1 is an independent alkyl group having 1 to 6 carbon atoms, or two groups are combined with a nitrogen atom to form a 3- to 6-membered heterocycle. is possible, and R2 is
A catalyst for producing polyurethane is described, which is a divalent organic group having no active group other than an amino group that can react with isocyanate.
Specifically, examples are described in which compounds such as dimethylaminopropylamine, diethylaminopropylamine, and N-(2-aminoethyl)aziridine are used as catalysts for producing polyurethane.

However, all of these compounds have low boiling points and extremely strong irritating odors, creating problems in terms of the working environment.

[Means for solving problems]

As a result of intensive studies to solve the above problems, the inventors of the present invention found that a compound having a dimethylamino group and two hydroxyl groups in the molecule has an extremely low odor and can be used as a catalyst for polyurethane production. It has a suitable activity of
Furthermore, the present invention was completed by discovering that it acts as a chain extender in polyurethane resins, improves the physical properties of the polymer, and does not migrate in polyurethane resins after polyurethane production.

That is, the present invention provides a catalyst for producing polyurethane comprising a compound represented by the following general formula (1) (wherein m and n represent integers such that m + n is 1 to 6). It is.

The novel catalyst for producing polyurethane of the present invention can be easily produced, for example, by adding ethylene oxide to dimethylaminopropylamine.

The amount of the novel catalyst of the present invention to be used is preferably in the range of 0.01 to 10 parts, particularly preferably 0.1 to 5 parts, based on 100 parts (by weight, the same applies hereinafter) of the polyol used for producing polyurethane. However, by controlling the amount of catalyst added, it is possible to use it outside this range for the purpose of optimizing the polyurethane manufacturing process. Furthermore, the novel catalyst of the present invention can be used in combination with tertiary amines and organometallic compounds, such as triethylene diamine and tetramethylhexamethylene diamine, which are commonly used in the production of polyurethane.

Polyisocyanates that can be used when producing polyurethane using the novel catalyst of the present invention include -
a Any known polyisocyanate may be used, such as 2.4-tolylene diisocyanate, 2.
Examples include 6-1-lylene diisocyanate, 4,4°-diphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and xylylene diisocyanate.

Polyols that can be used when producing polyurethane using the novel catalyst of the present invention include generally known polyether polyols and polyester polyols. For example, polyether polyols obtained by adding ethylene oxide or propylene oxide to polyhydric alcohols such as glycol, glycerine, pentaerythritol, trimethylolpropane, and sucrose, or ethylene diamine, tolylene diamine,
Examples include amine polyols obtained by adding ethylene oxide and propylene oxide to diamines such as diphenylmethane diamine, and polyester polyols produced from ordinary dibasic acids and polyhydric alcohols. Furthermore, there are polymer polyols among the polyols used when manufacturing polyurethane foams. It is made by polymerizing, in the presence of a free radical catalyst, one or more ethylenically unsaturated monomers dissolved or dispersed in any of the other types of polyols mentioned herein. Representative examples of ethylenically unsaturated monomers are as follows, which may be used alone or in combination. namely, ethylene, propylene, acrylonitrile, hinyl chloride, vinylidene chloride, styrene, methyl methacrylate, and butadiene. Generally, such compositions are prepared in a base polyol at a temperature between about 40°C and about 150°C using any of the radical generating initiators including peroxides, versalphates, percarbonates, perborates, and azo compounds. It is made by polymerizing monomers.

When producing polyurethane using the novel catalyst of the present invention, additives such as CFCh or CII□CI may be used as necessary.
A foaming agent such as No. 2, a surfactant such as organopolysiloxane, a flame retardant such as a halogenated alkyl compound or a halogenated phosphorus compound, and other additives can be used. The types and amounts of these additives can be sufficiently used within the types and ranges commonly used.

[Effect]

The present invention provides a catalyst for producing polyurethane comprising a compound represented by the following formula (wherein m and n represent integers such that m+n is 1 to 6). How the catalyst functions to bring about the effects of the present invention will be described.

The catalyst for producing polyurethane of the present invention has a high boiling point and therefore has extremely low odor. In addition, the catalyst of the present invention has (
Since it has a Clh)zN- group and has suitable activity as a catalyst for polyurethane production, it is thought that the polyurethane production process can be easily controlled. Furthermore, since the catalyst of the present invention has two hydroxyl groups in its molecule, by the end of the polyurethane production reaction, it reacts with the isocyanate group that is the polyurethane raw material, crosslinks into the polyurethane molecule, and cures. After finishing, the catalyst does not migrate to the surface of the product, which is thought to eliminate various problems caused by this phenomenon (yellowing, poor adhesion, etc.).

〔Example〕

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

Examples 1-2 and Comparative Examples 1-2 The mixing ratios of raw materials for producing polyurethane were as shown in Table 1, and urethane foaming was carried out according to the usual procedure. That is, polyol, water, surfactant, catalyst, blowing agent,
Polyisocyanate was weighed into a paper kelp kept at 20°C, mixed and stirred to form a urethane foam.

Evaluation results are shown in Tables 2 to 5. In the table, cream time means the time from the start of mixing the raw materials until foaming begins, and gel time means the time from when a thin wooden stick is brought into contact with the polyurethane foam surface and quickly pulled away. It refers to the time required for the molecular weight to increase enough to draw a thread. Tack-free time refers to the time it takes for a thin wooden rod to come into contact with the polyurethane foam surface until resin no longer adheres to the tip of the rod. Rise time means the time it takes for the polyurethane foam to reach its maximum apparent height.

Table 1 Book 1: Aromatic amine polyol (OH
V=450) *2; Sugar-based polyether bottle U manufactured by Bayer Urethane, t -/l/ (OIIV=450) *3;
Mitsui Toatsu Urethane Special Glycerin Polyny f/L
/ Ho'J, t-ru (OIIV = 235) *4; Surfactant manufactured by Nippon Unicar *5; Isocyanate manufactured by Mitsui Toatsu Urethane ■, mixture of crude MDI and TDI prepolymer (NCOχ = 31
) Table 2 Reaction rate of 2 mole ethylene oxide adduct of N,N-dimethylaminopropylamine Table 3 Reaction rate of 1 mole ethylene oxide adduct of N,N-dimethylaminopropylamine Table 4 N,N- Reaction rate of dimethylaminopropylamine
5 Table N,N-dimethylaminoethanol reaction rate Example 3
and Comparative Example 3 The mixing proportions of raw materials for producing polyurethane were as shown in Table 6, and urethane foaming was carried out according to the usual procedure. That is, polyol, water, catalyst, and polyisocyanate are measured and mixed in a spoon. The amount of catalyst used was adjusted to eight rounds so that the rise time was 90 seconds.

The vinyl chloride sheets to be provided had the formulations shown in Table 7, were kneaded and then pressed to form sheets.

Cut out a sample of about 3g from expanded polyurethane foam, and place it together with a 16cm2 vinyl chloride sheet.
Place it in a 30cm” sample bottle and heat it in a thermostatic oven at 110°C for 48 hours.
Let it stand for a while. After cooling to room temperature, the degree of discoloration of vinyl chloride was evaluated by measuring yellow index (Y, I). The results obtained are shown in Table 8.

Table 6 *l; Glycerin-based polyether polyol manufactured by Asahi Olin ■ (molecular weight approximately 6500.01 (V = 26) *2;
Dimer acid polyester manufactured by Kao ■ (OIIV・360)
*3; Polyether polio made by Mitsui Toatsutsurethane /
l/ (OHV=560) Book 4; Sumitomo Bayer Urethane G Chrysanthemum Crude MDI (
NCOχ=30.7) *5; Rise time was adjusted to 90±5 seconds Table 7 Table 8 Example 4 Odor evaluation was performed on the catalyst of the present invention and the comparative force insect medium. The evaluation method used is explained below.

The amine-based urethane catalyst was MN-700 (glycerin-based polyether polyol manufactured by Mitsui Toatsu ■, molecular weight approximately 700).
The odor was dissolved in water to a predetermined concentration and evaluated by a selected odor panel of 50 people. The results are shown in Table 9.

The criteria for odor evaluation are as follows.

◎: Almost no odor ○: Slight odor Δ: Odor ×: Strong odor
5%), and from the above table it can be seen how low odor the novel catalyst for producing polyurethane of the present invention is.

〔Effect of the invention〕

As specifically shown in the examples, the catalyst for polyurethane production of the present invention reacts with isocyanate groups and is incorporated into the polyurethane molecules at the end of the polyurethane production reaction, so that after the reaction is completed, the catalyst for producing polyurethane is This is a non-migration type catalyst for producing polyurethane that does not cause the catalyst to migrate. Furthermore, it has an economical advantage in that it has extremely low odor and has a stronger catalytic activity than methylmorpholine, ethylmorpholine, and dimethylbenzylamine, so that only a small amount is required.

In more detail regarding the non-migration performance, hitherto known catalysts such as triethylenediamine (TED
When polyurethane foam and vinyl chloride sheet are integrally molded using A), the vinyl chloride sheet may be colored yellow at a later date due to the transfer of triethylenediamine from the polyurethane foam to the vinyl chloride sheet after foaming and curing. , it has the disadvantage of discoloration. This phenomenon is accelerated by heating and has become a serious problem in the automobile industry, where many molded products of this type are used. However, by using the catalyst for producing polyurethane of the present invention, the catalyst does not migrate from the polyurethane foam, and the above-mentioned problems are solved.

Furthermore, the catalyst for producing polyurethane of the present invention has a relatively large molecular weight and a high boiling point, so its volatility is extremely low.
It has low odor. This makes it possible to significantly improve the working environment in the polyurethane manufacturing process.

Claims (1)

[Scope of Claims] A catalyst for producing polyurethane comprising a compound represented by the following general formula (1). ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) (In the formula, m and n represent integers where m+n is 1 to 6.)