JPH0747619B2 - Amine catalyst for producing polyurethane and method for producing polyurethane - Google Patents

Description

TECHNICAL FIELD The present invention relates to an amine catalyst for producing polyurethane such as soft, semi-hard, hard or elastomer. More specifically, the present invention relates to an amine catalyst for polyurethane production, which has a secondary hydroxyl group in the molecule, is non-migrating in a polyurethane resin, and is excellent in moldability, and a production method using the same.

[Prior Art] Polyurethane foams are usually produced by instantly stirring and foaming a polyol and a polyisocyanate containing a catalyst, a blowing agent (halogenated hydrocarbon and / or water), and optionally other auxiliary agents, and foaming. To be done.

Polyurethane foam is lightweight and has excellent cushioning properties, impact resistance, and anti-vibration properties, and is used in various products. Conventionally, amine catalysts such as triethylamine, N-ethylmorpholine, triethylenediamine, and tetramethylhexamethylenediamine have been used as catalysts for producing these polyurethane foams, and they have been produced with good moldability. However, polyurethane foam and other materials,
For example, vinyl chloride resin, ABS resin, polycarbonate resin, etc., and a product manufactured by combining or integrally molding in the form of foil, coating or edging material, for example, instrument panel, seat, headrest as interior material for automobiles. It is known that the use of these amine catalysts for, for example, armrests causes new problems. For example, the amine catalyst remaining in the polyurethane foam migrates to other materials with which it comes into contact, causing deterioration and discoloration, resulting in a decrease in commercial value.

Conventionally, as a method for solving this problem, a method of using an amine catalyst having a reactive primary amino group or secondary amino group in the molecule (JP-A-46-4846, JP-A-59-191743, JP-B-61-61). -31727), and a method using an amine catalyst having a reactive primary hydroxyl group in the molecule (JP-B-57-
14762) has been proposed. These amine catalysts accelerate the polyurethane foam formation reaction and, at the same time, have a reactive group in the molecule and thus react with the raw material polyisocyanate and are trapped in the polyurethane resin. Therefore, the problem of deterioration of physical properties and discoloration of the composite is avoided without transfer to other materials that come into contact. However, the amine catalyst having these reactive groups is trapped in the polyurethane resin, so that the catalytic activity is decreased during the reaction, resulting in insufficient formation of the polyurethane resin. For this reason, it has been pointed out that the moldability is deteriorated, and voids (voids) are generated in the polyurethane foam to increase the defective rate of the product.

That is, in a product produced by combining or integrally molding these polyurethane foams with other materials, a non-migrating type amine catalyst that does not deteriorate or discolor other materials in contact and is excellent in moldability is desired. .

[Problems to be Solved by the Invention] In view of these circumstances, the present invention provides an amine catalyst for polyurethane production which is non-migrating in a polyurethane resin and has excellent moldability, and a production method using the same. Is.

[Means for Solving the Problem] The inventors of the present invention have conducted extensive studies on an ami catalyst for polyurethane production and a method for producing the same.

As a result, an amine catalyst having a secondary hydroxyl group in the molecule as a catalyst is a non-migrating type in the polyurethane resin, and the catalytic activity does not decrease much during the polyurethane formation reaction, and the polyurethane foam and other materials are combined or integrated. With regard to products manufactured by molding, the present invention has been completed by discovering a new fact that is excellent in moldability without causing deterioration and discoloration of other materials that come into contact therewith.

That is, the present invention provides an amine catalyst comprising a compound represented by the following general formula (I) for producing a polyurethane, and a production method using the same.

(In the formula, n is an integer of 0 to 3, and R ₁ , R ₂ and R ₃ independently represent an alkyl group having 1 to 3 carbon atoms) [Action] Next, the present invention will be described in detail. .

The amine catalyst of the present invention is a tertiary amine compound represented by the general formula (I) and having a secondary hydroxyl group in the molecule.

These amine catalysts of the present invention include N, N-dimethyl-
N- (2-hydroxypropyl) amine, N, N, N'-trimethyl-N '-(2-hydroxypropyl) ethylenediamine, N, N, N', N "-tetramethyl-N"-(2-
Hydroxypropyl) diethylenetriamine, N, N, N ′,
Examples include N ″, N-pentamethyl-N- (2-hydroxypropyl) triethylenetetraamine,
Among these, N, N-dimethyl-N- (2-hydroxypropyl) amine and N, N, N'-trimethyl-N '-(2-
Hydroxypropyl) ethylenediamine, N, N, N ′, N ″
-Tetramethyl-N "-(2-hydroxypropyl) diethylenetriamine is more preferred.

These amine catalysts can be prepared by a method known in the art, for example, the corresponding alkanolamine is subjected to the Leukart-Wallach reaction described in U.S. Pat.No. 4026840 or the reductive alkylation reaction described in West German Patent No. 2618580. Can be manufactured using.

The amount of the amine catalyst of the present invention used for polyurethane production is
Usually, it is 0.02 to 10 parts by weight when 100 parts by weight of polyol is used. Known tertiary amine catalysts and organic carboxylic acid salts and organic tin compounds thereof which are commonly used as a co-catalyst can be appropriately used as a co-catalyst as long as the catalytic function of the present invention is not lost.

In the method for producing a polyurethane using the amine catalyst of the present invention, conventionally known polyols, polyisocyanates and, if necessary, a foaming agent, a foam stabilizer and other auxiliaries can be used.

Examples of the polyol include polyether polyol, polymer polyol and polyester polyol having two or more reactive hydroxyl groups. Examples of the polyether polyol include glycol, glycerin, pentaerythritol, polyhydric alcohols such as sucrose, ammonia, aliphatic amine compounds such as ethyleneamine, toluenediamine, aromatic amine compounds such as diphenylmethane-4,4′-diamine. And / or a polyether polyol obtained by adding ethylene oxide or propylene oxide to a mixture thereof. Examples of the polymer polyol include those obtained by reacting the polyether polyol with an ethylenically unsaturated monomer such as butadiene, acrylonitrile and styrene in the presence of a radical polymerization catalyst. Examples of the polyester polyol include those produced from a dibasic acid and a polyhydric alcohol, such as polyethylene adipate and polyethylene terephthalate type, and these may be those regenerated from wastes.

The polyisocyanate may be a known organic polyisocyanate, for example, toluene diisocyanate,
Aromatic polyisocyanates such as diphenylmethane-4,4'-diisocyanate and their polymerized isocyanates; Aliphatic polyisocyanates such as hexamethylene diisocyanate; Alicyclic polyisocyanates such as isophorone diisocyanate; or Toluene diisocyanates obtained by reacting them with polyols Examples thereof include isocyanate-terminated prepolymers such as prepolymers and diphenylmethane-4,4'-diisocyanate prepolymers; modified isocyanates such as carbodiimide-modified; and mixed polyisocyanates thereof.

Examples of the foaming agent include low boiling point halogenated hydrocarbons and / or water. Known halogenated methane and halogenated ethane can be used as the halogenated hydrocarbon, and among these, trichloromonofluoromethane (R-1
1) and freon compounds such as dichlorotrifluoroethane (R-123) and dichloromonofluoroethane (R-141b) are preferable. The amount used is not particularly limited, but normally 100 parts by weight of polyol, the amount of fluorocarbon used is 35 parts by weight or less, preferably 0 to 30 parts by weight, the amount of water used is 2.0 parts by weight or more, preferably It is 3.0 to 10.0 parts by weight.

The foam stabilizer is, for example, an organopolysiloxane-polyoxyalkylene copolymer, a nonionic surfactant such as a silicone-glycol copolymer, or a mixture thereof, and the amount thereof is not particularly specified. Usually, it is 0 to 2.5 parts by weight based on 100 parts by weight of polyol.

In the present invention, if necessary, other auxiliary agents can be added, and conventionally known flame retardants, colorants, extenders,
Examples thereof include antioxidants and UV inhibitors.

Polyurethane produced using the amine catalyst of the present invention is a conventionally known one-shot method, a flexible foam produced by a prepolymer method, HR foam, semi-rigid foam,
Rigid foams, microcellular foams, elastomers and the like. Of these, a method for producing a polyurethane foam that is foamed by using a foaming agent, in which already-formed polyurethane foam is combined with another material in the form of foil, coating or edging material, or is integrally molded, is particularly preferable. . Other materials include resins such as vinyl chloride resin, ABS resin, and polycarbonate resin, metals, glasses, and the like. Examples of products include instrument panels as interior materials for automobiles,
Examples include seats, headrests, armrests, door panels and packaging materials.

EFFECTS OF THE INVENTION Since the amine catalyst of the present invention has a secondary hydroxyl group in the molecule, it acts as a non-migration type catalyst in the polyurethane resin. Further, since the decrease in the catalytic activity during the polyurethane forming reaction is small, the moldability is excellent. Therefore, when the amine catalyst of the present invention is used in a product produced by combining or integrally molding a polyurethane foam and another material, a product having a low defect rate and not causing deterioration or discoloration of other materials in contact can be produced. .

[Examples] Hereinafter, the present invention and comparative examples will be described, but the present invention is not limited to these examples.

Examples 1 to 3 and Comparative Examples 1 to 5 In a semi-rigid foam formulation in which the mixing ratios (formulations) of the raw materials are as shown below, the catalysts of the Examples and Comparative Examples were used, and predetermined foaming conditions were used. A lower foaming test was conducted. The moldability evaluation of the generated polyurethane foam and the discoloration test of the vinyl chloride resin were conducted by the following methods. The results are shown in Table-1.

a. Formulation (parts by weight) Polyol 1) 100 water 2.8 Crosslinker 2) 3.0 Catalyst 3) Change Isocyanate 4) (NCO / OH = 1.05) 1) Polyether polyol, OHV = 33mgKOH / g (Sanyo Chemical Industries ( FA-703) 2) Triethanolamine (manufactured by Mitsui Toatsu Chemicals, Inc.) 3) Explanation of catalysts used and catalyst abbreviations in the table DMPA; N, N-dimethyl-N- (2-hydroxy) Propyl)
Amine TMAEPA; N, N, N'-trimethyl-N "-(2-hydroxypropyl) ethylenediamine TMDTPA; N, N, N ', N" -tetramethyl-N "-(2-hydroxypropyl) diethylenetriamine DMAPA; N , N-Dimethyl (3-aminopropyl) amine BDMAPA; Bis (3-dimethylaminopropyl) amine TMAEEA; N, N, N'-trimethylaminoethylethanolamine TEDA-L33; Triethylenediamine 33% dipropylene glycol solution ( Tosoh Corporation, TEDA-L33) TMHMDA; Tetramethylhexamethylenediamine (Tosoh Corporation, TOYOCAT-MR) 4) Crude MDI, NCO concentration = 31.0% (Nippon Polyurethane Industry Co., Ltd., MR-200) B. Foaming conditions Raw material liquid temperature 25 ± 1 ° C Stirring speed 6000 rpm (7 seconds) c. Measurement item At room temperature (20-25 ° C), the polyurethane raw material is poured into a polyethylene cup of 2 and allowed to foam to react. Foam density, measured the moldability.

・ Reactivity Cream time; Foam rise time (seconds) Gel time; Resin (stringing) time (seconds) Rise time; Foam rise stop time (seconds) ・ Foam density 6 × 6 × 6cm in the center of foam Measure the density with the test piece cut to the dimension.

・ Moldability Voids generated at the bottom of the generated foam
Was evaluated according to the following three grades.

Large void… × Small void… △ No void… ○ ・ Discoloration test Aluminum mold temperature controlled at 40 ℃ (dimensions: 12 × 50
A vinyl chloride resin sheet (GA-20; manufactured by Plastech Co., Ltd.) was set on the bottom of (× 2 cm), and a polyurethane raw material was poured on the sheet and foamed to obtain a test piece for discoloration test. This was placed in an oven, heated to 120 ° C., and the rate of discoloration after 200 hours was measured with a colorimeter (manufactured by Nippon Denshoku Co., Ltd.) and expressed as a color difference value (ΔE; difference from blank value).

As is clear from Table-1, the amine catalyst of the present invention has a small discoloration value and good moldability. On the other hand, the amine catalysts of Comparative Examples 1 to 3 had a small discoloration value, but the moldability deteriorated, and the amine catalysts of Comparative Examples 4 and 5 had a large discoloration value and could not be used together.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area C08G 101: 00) B29K 75:00 105: 00 C08L 75:04

Claims (5)

[Claims] 1. An amine catalyst for producing a polyurethane, which comprises a compound represented by the following general formula (I). (In the formula, n is an integer of 0 to 3, and R ₁ , R ₂ and R ₃ independently represent an alkyl group having 1 to 3 carbon atoms) 2. A catalyst of a polyol and a polyisocyanate,
Reacting in the presence of a blowing agent and optionally other auxiliaries,
A method for producing a polyurethane foam, which comprises using the amine catalyst according to claim 1 in the method for producing a polyurethane. 3. A method for producing polyurethane, characterized in that the polyurethane foam produced by the method according to claim (2) is combined with another material or integrally molded. 4. The method according to claim 2, wherein the blowing agent is water and / or a halogenated hydrocarbon. 5. The method according to claim 3, wherein at least one selected from vinyl chloride resin, ABS resin, and polycarbonate resin is used as the other material.