JPH04170417A - Production of reaction injection molded article - Google Patents

Abstract

PURPOSE:To obtain the title article with an excellent moldability and an excellent mold releasability at a high productivity by reacting and molding a specific mixture and a methylene diisocyanate prepolymer at room temp. by reaction injection molding. CONSTITUTION:A mixture obtd. by mixing an NCO-reactive polymer having a mol.wt. of 800-12,000 with a mixture of an arom. di- or polyamine having a mol.wt. of 400 or lower with ethylene glycol (e.g. Stacure 100, a product of Ethyl Corp.) and a methylene diisocyanate prepolymer are reacted and molded at room temp. by reaction injection molding to give the title article. The prepolymer has a specified NCO value and comprises a reaction product of a diisocyanate component mainly consisting of diphenylmethane 2,4-diisocyanate, diphenylmethane 4,4'-diisocyanate, or a mixture of these isomers, a condensation product contg. OH groups and ester groups, having a specified properties, and obtd. by reacting ricinolic acid with at least one mono- or polyhydric alcohol having a mol.wt. of 32-400 (e.g. 1,6-hexanediol), and a specific polyether polyol.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a reaction injection molded product using a specific methylene diisocyanate prepolymer (hereinafter referred to as rMDI prepolymer if necessary). Specifically, it relates to a manufacturing method using the RIM method (reaction injection molding method for polyurethane resin and/or polyurea resin) which has excellent productivity and moldability. The resulting molded product is suitable for use as exterior materials for automobile bumpers, fenders, and the like.

[Conventional technology]

Japanese Patent Publication No. 541735E1 discloses a urethane/urethane using a sterically hindered aromatic amine (DETIIA) as a chain extender.
A method of making a urea elastomer is disclosed.

Also, Japanese Patent Publication No. 63-5H87, Japanese Patent Publication No. 63-27362
In each publication No. 3, high molecular weight polyethers having amine 7 groups or imino groups at the terminals and sterically hindered aromatic amines (DE
A manufacturing method using TIIA) as a #1 sealant is disclosed. These methods are effective as a means of increasing productivity by using amines with rapid reactivity.

Furthermore, JP-A-60-500418 discloses a method for producing urethane/urea and urea elastomers using a fatty acid metal salt as an internal mold release agent.

Further, Japanese Patent Publication No. 1-29453 discloses a method for producing a urethane/urea elastomer using a polypropylene polyol, a sterically hindered aromatic amine (DETDA), and a specific ricinoleic acid ester compound as an internal mold release agent.

US Patent No. F7F4,888,224 discloses a manufacturing method in which a specific ricinoleic acid ester compound is reacted with an isocyanate compound and used as an internal mold release agent.

[Problem to be solved by the invention]

By using these conventional internal mold release agents, productivity can be increased by reducing the number of times external mold release agents are used.

However, when a fatty acid metal salt is used as an internal mold release agent, the mold release property is excellent, but the internal mold release agent tends to bleed onto the surface of the molded product, and when trichloroethane is used as a cleaning solvent, cleaning may be insufficient. There were problems with paint repellency and adhesion.

Furthermore, the method described in Japanese Patent Publication No. 1-29453 has the following problems. In other words, the same publication describes internal Jl-type agents with an average molecular weight of 800 to 4,500, which can be measured by osmotic pressure, an acid value of less than 5, and an O of 12.5 to 125.
The product consists of an ester group-containing condensation compound having an H value, and the product consists of 3 to 15 moles of ricinoleic acid and 1 mole of monohydric or polyhydric alcohol having a molecular weight of 432 to 400.
mol or a compound prepared from a mixture of several types of said monohydric or polyhydric alcohols. As a specific example.

3 to 15 moles of ricinoleic acid as internal mold release agent;
Dihydric alcohols having a molecular weight of ~400 (for example, 1,6-hexanediol as the dihydric alcohol) are mentioned.

When used in accordance with the internal mold release agent examples above, internal 1
Although the effect is certainly recognized when compared with the case without type Iil agent, when an internal mold release agent is added to the resin component, the terminal becomes a secondary OH, so the reactivity of NCO is low and the initial strength upon demolding is reduced. There was a problem. Therefore, industrial production processes using complex molds are insufficient.

In order to solve the above drawbacks, U.S. Patent No. 4,888゜2
When an internal mold release agent is added to the isocyanate side as described in the specification of No. 24, the initial strength can be improved to some extent, but it is insufficient, compared to when it is added to the resin component as described above. The reason for this can be assumed to be that intramolecular and intermolecular condensation reactions (side reactions) occur between ricinoleic acid and the oligomer during production of the internal mold release agent, reducing the number of functional groups in the final product.

Therefore, it is desirable to use polymeric MDI as shown in the examples of U.S. Pat. No. 4,868,224. There are stability issues. This is presumed to be due to poor compatibility between the internal mold release agent and hollybrobylene polyol, which is a modifier for the MDI prepolymer described in Examples in the same specification.

As mentioned above, when conventional specific ricinoleic acid ester compounds and isocyanate compounds are reacted and used as an internal mold release agent, although there is a mold release effect, the product M
Storage stability of DI prepolymer and strong If (
There was a problem with green strength).

Therefore, an object of the present invention is to provide a method for producing molded articles with excellent productivity and moldability by the RIK method by using an MDI prepolymer which has excellent storage stability and excellent initial strength.

[Means to solve the problem]

In order to achieve the above object, the present inventor has made extensive studies and has arrived at the present invention.

That is, the method for producing a reaction injection molded product according to the present invention can
A mixture is produced by mixing an isocyanate-reactive polymer (I) having a molecular weight of 00 to 12,000 and an aromatic diamine having a molecular weight of 400 or less or a mixture (II) of an aromatic polyamine having a molecular weight of 400 or less and ethylene glycol. , the mixture and liquid MD with an NCO content of 5 to 28%
I prepolymer (III) is reacted at room temperature to produce a molded article by a reaction injection molding method, the MDI prepolymer of (m) containing the following components (A), component (E), and component ( consisting of a mixed reaction product of C);
It is characterized in that the content of component (C) is 2 to 50%.

Component (A) Nidiphenylmethane 2,4'-diisocyanate and/or 4,4'-diisocyanate and/or diisocyanate whose main component is a mixture of isomers Component (B) Ricinoleic acid or 12-hydroxyl stearic acid 3
~15 mol and 14 or 2 selected from monohydric or polyhydric alcohols having a molecular weight of 32 to 400
produced from a mixture of at least 900
average molecular weight of 4500, acid number less than 10 and 1
Ester group-containing condensation compound component (C) having an OH value of 2.5 to 125 Polyether polyol or polyol having a molecular weight of 400 to 12,000 and having a primary amino group and/or a secondary amino group and/or an imino group at the end In a preferred embodiment of the invention, the above-mentioned aromatic diamine having a molecular weight of 400 or less is the following - Shipura CI), (II),
It is one type or a mixture of two or more types selected from the compounds represented by [m].

R7Re - [wherein, R1, R2, R3, R4, and R5 are hydrogen atoms or alkyl groups having 1 to 10 carbon atoms, and at least one of R1, R2, and R3 is ortho to at least one 7-mino group; It is located at R6, R7, Re, and Rq each represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n represents an integer of 1 to 10. ] Hereinafter, the present invention will be explained in detail.

The raw material for the MDI prepolymer of the component (m) used in the present invention contains the component (A), component (B), and component (C) as essential components.

The compound of component (B) is a specific fatty acid ester,
Specifically, a mixture of 3 to 15 moles of ricinoleic acid and/or 12-hydroxyl stearic acid and one or more monohydric alcohols or polyhydric alcohols having a molecular weight of 32 to 40 (l). and the product has a temperature of 900 to 4500°, preferably 2500 to 3
average molecular weight of 500, acid number below 10, preferably below 2 and between 12.5 and 125. Preferably 30-55 OH
It is an ester group-containing condensation compound having a valence. Preferred compounds of component (B) include fatty acid esters described in Japanese Patent Publication No. 1-29453.

If the molecular weight of the fatty acid ester is less than 900, the mold release performance will decrease, and if it exceeds 4,500, the viscosity will be high and the compatibility with the resin will be poor.

Furthermore, if the acid value exceeds 10, there will be a large amount of free acid, which will cause deterioration of the metal strands of the reactor and cause the sheathing of tall molded products to repel. If the OH value is too low, the viscosity of the fatty acid ester will be high and the compatibility with the resin will be poor, and if the OH value is too high, the mold release performance will deteriorate.

If the molecular weight of the monohydric or polyhydric alcohol, which is the M material of the fatty acid ester, exceeds 400, the viscosity of the fatty acid ester will be high and the compatibility with the resin will be poor; if it is less than 32, the reaction will be slow and This results in a decrease in mold performance.

Alcohols within the above-mentioned molecular weight range can also contain ether groups, and alkanols or cycloalkasols can also be used.

Specific examples of these include: (1) monohydric alcohols such as methanol, ethanol, n-hexanol, n-dodecanol, and n-octanol, (2) such as cyclohexanol, 1.6-hexanediol, 1.4-dihydroxycyclohexane, and glycerin. .

Polyhydric alcohols such as trimethylolpropane, ■ e.g. ethylene glycol, 1,2- and 1,3-dihydroxypropane, 1.2-, 1.3-11.4- or 2
, 3-dihydroxybutane, neopentyl glycol,
1.4-bis-hydroxymethyl-cyclohexane, 1
．． Examples include alkanediols having a molecular weight of 62 to 400, such as 8-dihydroxyoctane. Among them, the use of 1,6-hexanediol, which is a dihydric alcohol, is particularly preferable in terms of mold release properties.
No. 1453 has a restriction that the acid value be 5 or less, but in the present invention, it is possible to have an acid value of 10 or less.

The compound of component (C) used in the present invention has a molecular weight of 40
It is a polyether polyol having a molecular weight of 0 to 12,000, and is a compound having a terminal primary amino group and/or a terminal secondary amino group and/or a terminal imino group.

As the compound of component (C), Japanese Patent Publication No. 83-56887
The terminal aromatic polyether amines and aliphatic polyether amines described in the examples of the publication can be preferably used. Examples of aliphatic polyamines containing terminal imino groups also include polyetherimines described in Examples of JP-A-63-273623.

A particularly preferred example of a di- to tri-functional aliphatic polyether amine is Jeffa 1ne D manufactured by Texaco.
-230, D-400, D-2000, 7-50009
is raised.

MDI used as component (A) in the present invention is:
Diphenylmethane 2,4'- and/or 4,4'-diisocyanates and/or mixtures of isomers are used as the main component. Also as needed.

It may also contain polymeric MDI and/or carbodiimide.

The NCO content of the MDI prepolymer, which is the reaction product of component (A), component (B), and component (C), is 5 to 2.
It is in the range of 8%, preferably in the range of 10 to 25%. If the NCO content is less than 5%, the viscosity of the prepolymer becomes high, causing poor mixing during molding, and
Exceeding this is not preferable since storage stability of the prepolymer becomes a problem.

The content of component (C) is in the range of 2 to 50% by weight, preferably 5 to 25% by weight. If the amount is 2% by weight without swirling, mold releasability becomes a problem, and if it exceeds 50% by weight, storage stability of the prepolymer becomes a problem, which is not preferable.

The aromatic diamine used in component (II) is the above-mentioned -
Compounds represented by Funakura [1], (IT) or [m] are preferred, and specific examples include 2,4-diaminomesitylene, 1,3.5-triethyl-2,4-diaminobenzene, 1, 3.5-) diisopropyl-2,4-diaminobenzene, l-methyl-3,5-diethyl-2,4-diaminobenzene, l-methyl-3,5-diethyl-2,6
-Diaminobenzene, 4,6-dimethyl-2-ethyl-
1,3-diaminobenzene, 3,5.3', 5'-tetraisopropyl-4,4'-diaminodiphenylmethane, 3,5-diethyl-3', 5-diisopropyl-4,
4'-diaminodiphenylmethane, 1,3-dimethyl-
5-tert-butyl-4,6-diaminobenzene or 1,3-dimethyl-5-tert-butyl-2,6-
Diaminobenzene, or a mixture of such diamines, is preferred, 1-methyl-3,5-diethyl-2,4
-diaminobenzene and its 1-methyl-3,5-
Mixture with diethyl-2,8-diaminobenzene (DE
TDA) is particularly preferred.

When used as a mixture of aromatic polyamine and ethylene glycol, the aromatic polyamine is 4,4'-diaminodiphenylmethane (MDA), polymeric MDA
, TDA, DETDA, 1,1-dimethyl-4,6-dimethyl-5,7-diaminobenzene/.

Other adducts used in the present invention include catalysts, particularly tin salts of carboxylic acids, dialkyltin salts of carboxylic acids, dialkyltin mercaptides, dialkyltin dithioesters, and tertiary amines. In addition, a foam stabilizer, etc. may be used.
As an incyanate-reactive polymer having a molecular weight of 2000, as a compound falling within the above molecular weight range,
The above-mentioned component (C) and polyols containing two or more OH groups at the molecular terminals are included. Specifically, polyols including polyether polyols, polyester polyols, polycaprolactam polyols, polycarbonate polyols, castor oil, etc. are terminated with primary or secondary amines,
It also includes compounds substituted with imino groups, and also includes amine-terminated polyoxyalkylene polyethers in which the ends of polyols are substituted with aromatic primary amines.

Examples of polyoxyalkylene polyether terminals substituted with primary or aromatic primary amines include Japanese Patent Publication No. 63
The examples described in JP-A-56887 are preferable, and the examples of polyoxyalkylene polyethers having imino groups at the ends are preferably those described in the examples of JP-A-63-273823.

In the production method of the present invention, a specific isocyanate-reactive polymer (I) and a specific mixture (H) are mixed to produce a mixture, and a specific methylene diisocyanate-based prepolymer (III) is preferably mixed. In this method, the reaction is carried out at room temperature with an isocyanate index of about 70 to 130, and a molded article is produced by reaction injection molding.

The production method of the present invention is characterized in that the composition of the methylene diisocyanate prepolymer (1) is limited, and this configuration achieves the above-mentioned advantages.

Synthesis of fatty acid esters as internal mold release agents (IMR-A)
) Synthesized according to Example 2 of Japanese Patent Publication No. 1-29453. 7 moles of ricinoleic acid, 1 mole of 1,6-hexanediol, and 50 ppm of titanium tetrabutyrate are placed in a 3-liter flask and heated to 190°C, and the water produced under atmospheric pressure is extracted for 4 hours. All the water, including small amounts of organic components, is then distilled off over the course of 8 hours. The mixture is maintained at 20 lb for an additional hour and then cooled.

By the above method, an internal mold release agent having the following properties was obtained.

Acid value: 1.5 OH value: 35 Viscosity: 1300 cps/25°C (rMR-B) 7 moles of 12-hydroxyl stearic acid, 1 mole of 1,6-hexanediol, and 50 pp of titanium tetrabutyrate were placed in a 3-liter flask. The reaction was carried out in the same manner as IMR-A.

By the above method, an internal mold release agent having the following properties was obtained.

Acid value: 8.0 OH value = 40 Viscosity: 3300 cps/25°C (IMR-C) 7 moles of ricinoleic acid and 1 mole of 1,6-hexanediol were placed in a 3-liter flask and, without catalyst, IMR-A reacted in the same way.

By the above method, an internal mold release agent having the following properties was obtained.

Acid value: 6.7 OH value: 35 Viscosity: 1300 cps/25°C In addition, the following materials were used in the examples and comparative examples.

Aromatic diamine cross-linking agent (DETDA): Etacure-100 manufactured by Ethyl Corporation, active hydrogen number 830 mg/KO) I Aromatic diamine cross-linking agent (DAI): 1.1-dimethyl-4,6-dimethyl-5,7-diamitindan Active hydrogen number 550mg/KO) 1 Aromatic polyamine crosslinking agent (polymeric MDA
) Synthesis product of nearaniline and formaldehyde MDA
-150 Manufactured by Mitsui Toatsu Chemical Co., Ltd. Active hydrogen value 550 g/KOH PPG (A) Polyether diol with a molecular weight of 2000, prepared by adding propylene oxide using nitripropylene glycol as an initiator OH value = 56 Viscosity: 800 cps/25°C PPG (B): Polyether diol with a molecular weight of 5000, prepared by adding propylene oxide to glycerin as an initiator OH value: 34 Viscosity: 1100 cps/25°C Polyetheramine r JeHamine LMT-30
01J: A compound that suppresses terminal primary amines, which is obtained by reacting a mixture of 50 parts by weight of polyether triol with a molecular weight of 3,000 and 50 parts by weight of polyether diol with a molecular weight of 2,000 manufactured by Texaco Chemical Company with ammonia in the presence of a catalyst.

Polyetheraminer JeffamineD-20
00J: A compound having a terminal primary amine obtained by reacting polyether diol of Molecule-M2000 manufactured by Texaco Chemical Company with ammonia in the presence of a catalyst.

DABCO33LV 33% solution of triethylene diamine in dipropylene glycol (DPG) as a solvent (catalyst) DBTDL Nidibutyltin laurate (catalyst) A E-300: Product name manufactured by Mitsui Toatsu Chemical Co., Ltd. 4 mole adduct of ethylene diamine with propylene oxide D-400: Trade name, molecular weight 4, manufactured by Texaco Chemical Company
Terminal armine polyether less than 00.

Production Example of MDI Prepolymers MDI prepolymers (A) to (J) were produced as follows, and their storage stability was evaluated and their NCO content and viscosity were measured.

MDI prepolymer (A): 14.1 parts by weight of tripropylene glycol was inserted into 85.8 parts by weight of 4,4'-diphenylmethane diisocyanate, and the mixture was stirred at 80°C.

The product remained clear after one week.

NCO content 22.5%, viscosity 800cps/25℃MD
I prepolymer (B): 14.1 parts by weight of tripropylene glycol was inserted into 85.9 parts by weight of 4.4'-diphenylmethane diisocyanate, and after mixing and stirring at 80°C for 2 hours, IMR-A
14.2 parts by weight of was added and further mixed and stirred for 1 hour.

The product was transparent, but crystals precipitated after 18 hours.

NCO content 19.5%, viscosity 800cps/25℃MD
I prepolymer (C): 80 parts by weight of 4.4'-diphenylmethane diisocyanate and 20 parts by weight of 4.4'-diphenylmethane diisocyanate containing 25% of 2.4'-diphenylmethane diisocyanate at 90°C. After mixing and stirring, add 41% of polyetheramine r Jeffamine D-2000J.
．． 6 parts by weight was added dropwise and mixed and stirred.

The product remained clear after one week.

NCO content 21.7%, viscosity 1500cps/25℃M
DI prepolymer (D): 80 parts by weight of 4,4'-diphenylmethane diisocyanate and 20 parts by weight of 4,4'-diphenylmethane diisocyanate containing 25% of 2,4'-diphenylmethane diisocyanate at 80°C. After mixing and stirring, add 4 ml of polyether amine r Jeffamine D-2000J.
After dropping 1.6 parts by weight and mixing and stirring, I MR-A2
0.0 part by weight was added and further mixed and stirred for 1 hour.

The product remained clear after one week.

NCO content 20.4%, viscosity 900cps/25℃MD
I prepolymer (E): An MDI prepolymer was synthesized according to Example 1 using IMR-B.

The product remained clear after one week.

NCO content 20.2%, viscosity 1200cps/25℃M
DI prepolymer (F): An MDI prepolymer was synthesized using IMR-C in the same manner as the MDI prepolymer (D).

The product remained clear after one week.

NCO content 20.4%, viscosity 900cps/25℃MD
I prepolymer (G) 30% 2,4'-diphenylmethane diisocyanate
After mixing and stirring 20 parts by weight of MDI and 80 parts by weight of carbodiimide-modified MDI having an NCO content of 29% at 90°C, 32.8 parts by weight of PPG (A) was added, and 2 parts by weight of PPG (A) were added.
After mixing and stirring for hours, 20 parts by weight of polymeric MDI having an NCO content of 31.5% was inserted.

The product remained clear after one week.

N00% 22.8%, 1100 cps/25°C MDI prepolymer (H): 30% 2.4'-diphenylmethane diisocyanate
20 parts by weight of MDI containing 20 parts by weight and 80 parts by weight of carbodiimide-modified MDI having an NCO content of 29% were mixed at 90°C, then 32.8 parts of PPG (A) was added, and after mixing and stirring at 80°C with 2br, IMR- After adding 13.3 parts by weight of A and stirring for 1 hour at 80°C, the NCO content was 31
．． 20 parts by weight of 5% polymeric MDI were inserted.

Although the product became cloudy, no crystal precipitation occurred after one week.

NCO content 20.4%, viscosity 1100cps/25℃M
DI prepolymer (I): 30% 2,4'-diphenylmethane diisocyanate
20 parts by weight of MDI containing 20 parts by weight and 80 parts by weight of carbodiimide-modified MDI having an NCO content of 29% were mixed and stirred at 80°C, then 32.8 parts by weight of rJeffamine D-2000J was added, and after mixing and stirring at 80°C for 2 hours, the NCO content was 31%. 20 parts by weight of .5% polymeric MDI were inserted.

The product showed no crystal precipitation after one week.

NCO content 22.8%, viscosity 1300cps/25℃M
DI prepolymer (J).

2.30% 4'-diphenylmethane diisocyanate
After mixing and stirring 80 parts by weight of MDI containing MDI and 20 parts by weight of carbodiimide-modified MDI having an NCO content of 29% at 90°C, 32.8 parts by weight of rJeffamine D-2000J was added dropwise, and after mixing and stirring at 80°C for 2 hours, I
After inserting 13.3 parts by weight of MR-A and mixing and stirring at 80°C for 2 hours, a polymeric MD with an NCO content of 31.5% was prepared.
I 20f! I inserted a quantity.

The product remained clear after one week.

NCO content 19.7%, viscosity +200cps/25℃ [
Examples] Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Using the MDI prepolymers (A) to (F) obtained in Production Examples and the raw materials shown in Table 1, RIM molding as shown below was carried out.

(Molding) A flat sheet was created by RIM molding using a Toho Kikai m1ni-RIM foaming machine. Mold size is 200X3
00X 3mm and the mold temperature was set at 70°C. The discharge rate was maintained at 200 g/see, the resin temperature at 40°C, the isocyanate temperature at 40°C, and the amount of air in the resin at 30%.

When using an external mold release agent, use rD-18 manufactured by Middle East Yushi Co., Ltd.
It was applied by spray using No. 8,+.

(Evaluation) Mold release number The mold release number is rD-18 after thoroughly washing and drying the mold with DMF.
6J was sprayed, the residence time in the mold was fixed at 30 seconds, and the number of times the mold could be continuously released from the mold was measured.

Green Strength After demolding, the molded sheet was bent 180 degrees and the time (sec) during which no cracks occurred was measured and determined as green strength.

Flex, M (flexural modulus) JISK-7
Table 1 shows the evaluation results for the 203 test method and above.

As is clear from Table 1, when using an internal mold release agent on the resin side (sample No. 2), the number of times of mold release is more effective compared to sample No. 1) without an internal mold release agent. , it can be seen that the green strength becomes better.

Also, when a fatty acid ester internal LA type agent is used on the isocyanate side (sample No. 3), green strength is improved, but sample No. without an internal mold release agent.

It can be seen that this is insufficient when compared with (1).

Furthermore, it can be seen that even when a polyether polyol having a terminal primary amino group is added to the prepolymer side without an internal mold release agent as in Sample No. 4, the number of mold release times does not increase.

On the other hand, in the case of samples N No. 5 to 7 of the present invention, it can be seen that the mold releasability and green strength are significantly improved.

Example 2 Evaluation was carried out in the same manner as in Example 1 except that the crosslinking agent DETDA was replaced with 1,1-dimethyl-4,6-dimethyl-5,7-diamitintan. The results are shown in Table 2.

As is clear from Table 2, in the case of sample No. 2 of the present invention, +2, it can be seen that the green strength and the number of times of mold release are improved.

Example 3 In Example 1, the crosslinking agent DETDA was replaced with MDA-150.
The evaluation was carried out in the same manner except that a mixture of and EG was used instead. The results are shown in Table 3.

As is clear from Table 3, the trial of the present invention $4 No. +7
In the case of , it can be seen that the green strength and the number of times of mold release are improved.

Example 4 In Example 1, raw materials were formed as shown in Table 4 and evaluated.

The results are shown in Table 4.

As is clear from Table 4, sample No. 22 of the present invention has improved mold releasability and green strength.

Example 5 In sample No. 5 of Example 1, when the content of component (n) in the MDI prepolymer was changed to 40% by weight, it was confirmed that the mold releasability and green strength were improved.

〔Effect of the invention〕

According to the present invention, it is possible to provide a method for producing a reaction injection molded product which has excellent mold releasability and excellent storage stability without delaying demolding time (internal curing time).

Patent applicant: Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] (1) An isocyanate-reactive polymer (I) having a molecular weight of approximately 800 to 12,000 is mixed with an aromatic diamine having a molecular weight of 400 or less or a mixture of an aromatic polyamine having a molecular weight of 400 or less and ethylene glycol (II). A mixture is prepared and the mixture has a liquid NCO content of 5 to 2.
8% methylene diisocyanate prepolymer (III
) are reacted at room temperature to produce a molded article by reaction injection molding, wherein the methylene diisocyanate prepolymer of (III) is reacted with the following components (A), component (B), and component (C). ), the content of component (C) is 2 to 50
% of a reaction injection molded product. Component (A): Diisocyanate whose main component is diphenylmethane 2,4'-diisocyanate and/or 4,4'-diisocyanate and/or a mixture of isomers Component (B): Ricinoleic acid or 12 Hydroxyl stearic acid 3
~15 mol and one or two selected from monohydric alcohols or polyhydric alcohols having a molecular weight of 32 to 400.
produced from a mixture of more than one species, and the product is
average molecular weight of 4500, acid number less than 10 and 12
．． Ester group-containing condensation compound component (C) having an OH value of 5 to 125: polyether polyol having a molecular weight of 400 to 12,000 and having a primary amino group and/or a secondary amino group and/or an imino group at the end. (2) The aromatic diamine with a molecular weight of 400 or less according to claim 1 is one type or a mixture of two or more types selected from the compounds represented by the following general formulas [I], [II], and [III]. A method for producing a reaction injection molded product, characterized by: General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ General formula [II] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ General formula [III] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R_1 , R_2, R_3, R_4, R_5 are hydrogen atoms or alkyl groups having 1 to 10 carbon atoms, and R_1, R
At least one of _2 and R_3 is in a position ortho to at least one amino group. R_6, R_7,
R_8 and R_9 represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and n represents an integer of 1 to 10. ]