JPS63135413A - Polyether-amine composition for reaction injection molding - Google Patents

Abstract

PURPOSE:To make possible the formation of polyether-amine composition for reaction injection molding, which can provide moldings having excellent mold release characteristics, heat resistance and appearance, by mixing a liquid aromatic polyisocyanate, a long-chain molecular polyether-amine, a specified aromatic polyamine as a chain-lengthening agent, and other auxiliaries. CONSTITUTION:The titled composition is formed from the following ingredients a-d: (a) is an aromatic polyisocyanate which is liquid at room temperature, (b) is a long-chain molecule polyether-amine having at least two isocyanate- reactive groups and a molecular weight of 1,000-12,000, in which at least 50% of the isocyanate-reactive groups are primary and/or secondary amino groups, (c) is an aromatic polyamine of formula 1 (where R is methyl, ethyl, propyl or isopropyl group; X is an R or OR group; n is O or an integer of 1-3; and the molar ratio of R to OR is 5:95-60:40), and (d) includes a catalyst, a foaming agent, an internal mold release, a filler and other auxiliaries, if necessary.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an organic polyetheramine composition used in reaction injection molding, particularly a highly reactive polyisocyanate,
The present invention relates to a polyetheramine composition which is used to produce elastic molded articles having a dense surface by reaction injection molding technology, using a high molecular weight polyetheramine and an aromatic polyamine chain extender.

Polyurethane elastic molded products, which have a dense surface and excellent physical properties, moldability, and appearance, are widely used. Specific examples of reactions include a wide range of products such as automobile plate materials, sports and leisure goods, office equipment housings, furniture, and agricultural equipment. The most commonly used of these are automobile bumpers, fascias, fenders, doors, side moldings, and the like.6 The present invention has such a very wide field of application, The aim is to provide materials with higher performance and economic value.

(Prior Art) It is known to mold non-foamed polyurethanes, their fiber-reinforced elastomers or microcellular polyurethane elastomers by reaction injection molding by polyaddition of isocyanates and isocyanate-reactive compounds. The raw materials for these polyurethanes are usually polyisocyanates, polyether polyols and polyester polyols with hydroxyl groups, chain extenders, catalysts and optionally blowing agents, auxiliaries, additives and fibrous inorganic compounds, reaction injection molding. Law is Reaction Injection
Molding (hereinafter referred to as RIM) is a process in which an isocyanate and an isocyanate-reactive component mixture are impingement-mixed using a mixing injection machine under pressure (often under high pressure), and this mixture is filled into a mold and cured, followed by a molded product. This is how to take it out.

Among these raw materials used, chain extenders are particularly important because they have a great influence on moldability and physical properties. Conventionally, ethylene glycol or 1,4-butanediol has been generally used as a chain extender, but neither of them necessarily provides sufficient performance in terms of moldability and physical properties. Specifically, for example, curing properties, void generation rate, mold releasability, heat resistance, tensile properties, etc. were not sufficient.

(Problem to be solved by the invention) Various improvements have been attempted to address these problems.

For example, in JP-A-56-109216, a relatively large amount of an aliphatic amine chain extender is used in combination with ethylene glycol to improve mechanical strength and heat resistance. However, since this method uses ethylene glycol as the main chain extender, significant improvements in mechanical strength and heat resistance cannot be achieved. In addition, the aliphatic amine with a relatively large molecular weight, which is most commonly used (used and considered "preferred") in the patent, itself does not significantly improve curing properties and heat resistance.

Another method is, for example, as disclosed in JP-A-52-77200, in which a small amount of a polynuclear mixed polyamine synthesized as an aromatic polyamine by condensation of aniline and formalin is used in combination with ethylene glycol to improve heat resistance.

Aromatic polyamines have a very large effect on improving heat resistance, but with this method, the high reactivity of the aromatic polyamines used reduces the ability to fill the mold during reaction injection molding, resulting in unsatisfactory molding. The amount of use is limited because it cannot be obtained. Furthermore, since alkanediol is used, no significant improvement in heat resistance can be expected.

Another method is to use halogen-containing diaminobenzene as a chain extender to improve heat resistance, as disclosed in JP-A-58-32626. In this method, the reactivity of halogen-containing diaminobenzene is moderately fast, but
On the other hand, curing is slow and problems remain in molding.

Furthermore, for example, in the method of using short molecular polyol such as ethylene glycol and long chain polyether polyamine in combination as shown in JP-A-58-187419, the reactivity of ethylene glycol which forms hard segments is slower than that of long chain polyether polyamine. , it exhibits sufficient elasticity during demolding, and its heat resistance is also poor.

As we have seen above, most chain extenders, which greatly affect the performance of polymers, are unsatisfactory in terms of physical properties and moldability. Further, even if the aromatic diamine has satisfactory physical properties, it is not compatible with other components, which causes various problems during molding operations.

(Means for Solving the Problems) In order to improve the curing properties, mold releasability, and heat resistance, which are the drawbacks of urethane tM by conventional glycol curing, the present inventors created a product obtained by condensing orthoanisidine and formalin. A patent application was filed for the use of aromatic polyamines as chain extenders (Japanese Patent Application No. 6O-248987).

Although this aromatic polyamine is extremely effective as a solution to the above-mentioned problems, it is necessary to improve its poor compatibility with long-chain molecular polyols due to its high melting point. As a result of further intensive studies to improve this point, we discovered that it is effective to combine a formaldehyde condensation product of orthoalkylaniline and orthoalkoxyaniline with a long-chain polyether having an isocyanate-reactive amino group at the end. , arrived at the present invention.

That is, the present invention comprises (a) an aromatic polyisocyanate that is liquid at room temperature; (b)
It has at least two inocyanate-reactive groups, has a molecular weight of 1,000 to 12,000, and at least 50% or more of the isocyanate-reactive groups are primary and/or secondary.
(c) General formula [wherein R is a methyl group, ethyl group, propyl group or isopropyl group, X is an R or OR group, and n is 0'.

or an integer from 1 to 3, and the molar ratio of R and OR is 529
5-60: 40. ] This is a polyetheramine composition for reaction injection molding, which comprises an aromatic polyamine represented by: and optionally (d) a catalyst, a blowing agent, an internal mold release agent, a filler, and other auxiliaries.

In the present invention, by mixing orthoalkylaniline with orthoalkoxyaniline, the crystallinity and melting point of the aromatic polyamine obtained by condensation with formaldehyde are reduced. As a result, the compatibility with long-chain polyether amine molecules is improved.

Furthermore, by using a partially aminated polyether amine instead of the conventionally used long-chain polyol, mold releasability is improved, and in some cases, RIM molding can be performed without using a catalyst. By making the reaction system non-catalytic, it is possible to add components that inhibit the catalyst, and for example, it is also possible to further improve mold release properties by adding an internal mold release agent that inhibits the catalyst. becomes. Furthermore, in the absence of a catalyst, heat resistance that can withstand high-temperature baking during painting can also be obtained. Furthermore, carbon dioxide gas, which tends to inhibit the catalyst, can also be used as a blowing agent. Since carbon dioxide gas has better compatibility with bevoliol or polyetheramine than nitrogen gas, the amount of gas charged can be increased and a good molding surface condition can be obtained.

The aromatic polyamine used as component (c) in the present invention is produced by condensing orthoalkylaniline and orthoalkoxyaniline with formaldehyde.

Orthoalkylanilines are specifically orthotoluidine, orthoethylaniline, orthopropylaniline, and orthoisopropylaniline.

Specific examples of orthoalkoxyaniline include orthoanisidine, orthophenetidine, orthopropoxyaniline, and orthoisopropoxyaniline, of which orthoanisidine is particularly preferred.

The molar ratio of orthoalkylaniline to orthoalkoxyaniline is preferably from 5:95 to 60:40, and particularly preferably from 10:90 to So:50. The aromatic polyamine produced under these conditions contains 4
゜4゛-diamino-3-alkyl-3゛-alkoxydiphenylmethane is present in the largest amount, and 4゜4゛-diamino-3,3'-dialkoxydiphenylmethane and 4.4''-diamino-3,3 Contains °-dialkyldiphenylmethane.If the molar ratio of orthoalkoxyaniline is out of this range, the compatibility with other components will decrease and the smooth progress of the reaction will be inhibited.

In this general formula, R represents a methyl group, ethyl group, propyl group or isopropyl group, X represents R or an OR group, and n represents O or an integer of 1 to 3.

The above amine preferably has a dinuclear (n-0):trinuclear or more (n-1 to 3) ratio of 90:10 to 40:60 (w
tZ), because if there are many polynuclear bodies, the reactivity of some of the amino groups will decrease too much.

The aromatic polyamine of component (c) can be obtained, for example, by reacting orthoalkoxyaniline and orthoalkylaniline in an aqueous formalin hydrochloric acid solution, followed by rearrangement at high temperature and neutralization with alkali.

Aromatic polyamine is a long chain molecule polyether amine 100
It is used in an amount of 10 to 70 parts by weight.

Examples of the aromatic polyisocyanate used as component (a) in the present invention include 4.4°-diphenylmethane diisocyanate, 2.4-&hy/or 2.6-
) lylene diisocyanate, polymethylene polyphenyl polyisocyanate, xylylene diisocyanate, dimers, trimers, carbodiimide modified products, allophanate modified products, beureft modified products, prepolymers, etc. of these isocyanates.

Among these aromatic polyisocyanates, particularly preferred isocyanate compounds for the present invention are derivatives of 4,4"-diphenylmethane diisocyanate, which are liquid at room temperature. Specific examples of this compound include the following: 4,4°-diphenylmethane diisocyanate and a low molecular weight diol or triol (preferably 70
Urethane group-containing polyisocyanate obtained by reacting with polypropylene glycol having a molecular weight of less than 0: 4,4''-diphenylmethane diisocyanate-based diisocyanate containing a carposiimide group and/or urethane imine group. Examples include: modified products made by modifying mixtures of 2,4'- and 4,4'-diphenylmethane diisocyanates as described above; 4,4'-modified as described above; A mixture of diphenylmethane diisocyanate and a small amount of polyisocyanate having a higher functionality than the difunctionality of the diphenylmethane series.

The polyether amine used as component (b) in the present invention is a polyether amine having an average molecular weight of 1,000 to 12,000, preferably 2,500 to 8,000 and having a small number of divalent isocyanate-reactive groups at the terminals. At least 50 equivalent % (preferably 80-100 equivalent %) of the reactive end groups are primary and/or secondary (preferably primary) amino groups attached by aliphatic bonds, the remainder being aliphatic. Preference is given to primary and/or secondary hydroxyl groups bonded by group bonds.

This polyetheramine can be produced by a known method. One known method is the amination reaction of polyhydroxy polyethers (eg polypropylene ether glycol).

For example, US Pat. No. 3,654,370.3838,076 describes a method for producing polyether amines by reacting polyols, ammonia and hydrogen under high pressure in the presence of nickel, chromium and copper catalysts.

When carrying out the present invention, the equivalent ratio of NGO,l contained in the aromatic polyisocyanate to the active hydrogen contained in the polyether amine and the aromatic polyamine is 0.8 to
Adjust the amount of each raw material used so that it becomes 1.3.

Catalysts optionally used as component (d) in the present invention include metal catalysts such as dibutyltin diacetate, dibutyltin dilaurate, tin oleate, tin octoate, and triethylamine, N, N, N', N ' There are amine catalysts such as tetramethyl-propanediamine, 1,4-diazabicyclo-(2,2,2)-octane, and pentamethyldiethylenetriamine.

Foaming agents include trichlorofluoromethane and CCIgF.
, CChFz, methylene chloride, water, nitrogen gas,
Carbon dioxide gas etc.

There are various types of internal mold release agents, such as silicone-based ones, fatty acid metal salts, fatty acid amide derivatives, fatty acid ester derivatives, etc.

Fillers include glass fiber, flake glass, mica,
Other auxiliary agents include talc, inorganic compound whiskers, etc., pigments such as carbon, antioxidants, weathering stabilizers, etc.

(Function) In the present invention, the melting point of the aromatic polyamine is lowered and the compatibility with the polyether amine is increased.

(Example) A mixed stock solution was prepared using the above raw materials, and RIM molding was performed in a mold using an injection molding machine for polyurethane.

Synthesis examples and examples of aromatic polyamines will be described below.

Synthesis Example 1 42.8 g of 0-toluidine (0,
4 mol), 0-anisidine 197 g (1.6 mol)
, 197.8 g (1.3 mol) of 24% hydrochloric acid was added and mixed, and then 111 g (1.0 mol) of 37% formalin was added dropwise at 30°C or below over 1 hour. After continuing stirring at the same temperature for 1 hour, the temperature was raised to 100°C and maintained at 100°C for 1 hour.

After the reaction, 116 g (1.3 mol) of 45% aqueous sodium hydroxide solution was added and stirred at 80° C. for 30 minutes. The precipitated oil is separated and washed three times with warm water at 80°C. This is 80
Dehydration was performed at °C to obtain 256 g of methylene-crosslinked aromatic polyamine. The yield is 94.8%. The product melts as a brown solid;
to 70-90℃, contains dinuclear bodies! The polynuclear substance content was 16.7%, and the amount of methyl gluttony was 2.2wt%.

This was designated as aromatic polyamine-1.

Synthesis Example 2 64.2 g of 〇-toluidine (0,
6 mol), 0-anisidine 172 g (1.4 mol)
, 197.8 g (1.3 mol) of 24% hydrochloric acid was added and mixed, and then 111 g (1.0 mol) of 37% formalin was added dropwise at 30°C or below over 1 hour. After continuing stirring at the same temperature for 1 hour, the temperature was raised to 100°C and maintained at 100°C for 1 hour.

After the reaction, 116 g (1.3 mol) of 45% aqueous sodium hydroxide solution was added and stirred at 80° C. for 30 minutes. The precipitated oil is separated and washed three times with warm water at 80°C. This is 80
Dehydration was performed at °C to obtain 251 g of methylene-crosslinked aromatic polyamine. The yield is 95.2%. The product was a brown solid with a melting point of 70 to 90°C, a dinuclear content of 81.0%, a polynuclear content of 19.0%, and a methyl group content of 3.4%. This was designated as aromatic polyamine-2.

Polyetheramine A: Polyether diamine with an average molecular weight of 2000 and an amination rate of 9594 obtained by addition polymerizing propylene oxide to propylene glycol and then amination (manufactured by Texaco, Jeffamine D-200)
0).

Polyetheramine B...average molecule z obtained by addition polymerizing propylene oxide to glycerin and then aminating it
s o o o, polyether triamine with an amination rate of 95% (Diefamine T-5000, manufactured by Texaco)
.

Isocyanate A...N obtained by reacting diphenylmethane diisocyanate and tripropylene glycol
Brevolimerisonanate B with a C○ group content of 22%...An NC○ group content of 26% obtained by reacting a mixture of diphenylmethane diisocyanate and its carbodiimide modified product with tripropylene glycol. Repolymer.

Examples 1-3 Polyetheramine A (ether-A) in the amounts shown in Table 1
), polyether amine B (ether-B), and aromatic polyamine-1 or -2 were mixed to prepare a resin liquid.

The resin solution was reacted with isocyanate A or isocyanate B.

The reaction injection molding machine is LRM- manufactured by Cincinnati Milacron.
L15 type was used. The mold is 900x 600x 2.
A 5 m sheet mold was heated to 75°C.

The temperature of the stock solution was adjusted to 30° C., and the flow rate ratio of the resin solution to the isocyanate component was adjusted as shown in Table 1. Dry nitrogen gas was mixed and dispersed in the resin liquid in an amount of 15% by volume, and the mixture was injected into the mold at an injection speed of 2000 g/sec and an injection time of 1 second.

The molds were demolded 40 seconds after injection, and the quality of the mold releasability and the elasticity immediately after demolding were compared. Immediately after demolding, the molded product was bent 180 degrees and the time required for no cracking to occur was measured. The surface condition of the molded product and the presence or absence of voids were also examined. Furthermore, test pieces were cut out from the molded products and their tensile strength, elongation, notched eye shift impact value, bending modulus, and heat resistance were measured. For the heat resistance test, a 2 x 15 am short strip test piece was
It is fixed horizontally at the cIm position and left in a constant temperature bath at 120°C for 1 hour. The distance that the other end sags after being left alone (
Thermal sag) was measured and the heat resistance was compared. The results were as shown in Table 2.

Comparative Example 1 A sample was treated in the same manner as in Example except that ethylene glycol was used instead of the aromatic polyamine of the present invention. The stock solutions were formulated as shown in Table 1, and the results obtained were as shown in Table 2.

Comparative Example 2 A sample was treated in the same manner as in Example except that diethyltoluenediamine (DETDA) was used instead of the aromatic polyamine of the present invention. The formulations were as shown in Table 1, and the results obtained were as shown in Table 2.

(Effects) As is clear from Tables 1 and 2, as a result of adjusting the reaction rate according to the present invention, the filling property into the mold is improved, the mold releasability, the elasticity immediately after demolding, the voids are improved, and the strength is improved. , Amendment to Table 1, Table 2 procedure for obtaining a molded product with excellent heat resistance, etc. (voluntary) February 29, 1988

Claims (1)

[Claims] (a) an aromatic polyisocyanate that is liquid at room temperature; (b)
It has at least two isocyanate-reactive groups, has a molecular weight of 1,000 to 12,000, and at least 50% or more of the isocyanate-reactive groups are primary and/or secondary.
Polyetheramine (c) is a long-chain molecule that is a class amino group General formula ▲ Numerical formula, chemical formula, table, etc. ▼ [However, R is a methyl group, ethyl group, propyl group, or isopropyl group, X is an R or OR group, n is 0 or 1-3
represents an integer, and the molar ratio of R and OR is 5:95 to 60:
It is 40. ] A polyetheramine composition for reaction injection molding, which comprises an aromatic polyamine represented by: and optionally (d) a catalyst, a blowing agent, an internal mold release agent, a filler and other auxiliaries.