JPH07268206A - Method for producing molded polyurethane and / or polyurea having excellent self-releasing property - Google Patents

Abstract

(57) [Summary] [Objective] In a method for producing a polyurethane and / or polyurea resin molded product by reaction injection molding, by using a specific internal release agent, it has good releasability from a mold, Provided is a molded product having excellent paintability and physical properties. [Structure] (a) an organic polyisocyanate, and (b) a polyol and / or polyamine, a chain extender (c) an internal mold release agent (d) a polyol mixed solution containing a foaming agent and an auxiliary agent as required. In the method for producing a polyurethane and / or polyurea molded product by reaction injection molding, a specific aliphatic ketone is used as an internal mold release agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an internal release agent.
More specifically, the present invention relates to a production method using a specific internal release agent in the production of a polyurethane and / or polyurea molded article having excellent self-release properties by reaction injection molding.

[0002]

2. Description of the Related Art Polyurethane and / or polyurea moldings are excellent in mechanical properties such as tensile strength, heat resistance and impact resistance, and moldings obtained by reaction injection molding are automobile parts, electronic parts. Used for parts and furniture. However, urethane bond and urea bond are
Although it depends on the molecular structure of the resin skeleton, an external or internal mold release agent is required to release the molded product from the mold because it has adhesiveness to metal. Since polyurea resin has a higher reactivity than polyurethane resin, continuous demolding is possible to some extent by using an external mold release agent, but as a method for making it easier to demold a molded product,

For example, as an external release agent, (a) a method of applying an organosilane compound to a mold to mold a polysiloxane compound (Japanese Patent Publication No. 3-11248), (b)
Mold release agent composed of isobutylene oligomer and wax (Japanese Patent Publication No. 3-11604), (c) Mold release agent containing halogen-containing polyether as a main component (Japanese Patent Publication No. 3-9848)
It is described to use.

These methods reduce the adhesive force between the mold and the interface of the molded article in the production of polyurethane and / or polyurea molded articles, and are effective to some extent in reaction injection molding. However, these external mold release agents are not always satisfactory in mold releasability, it takes time and effort to mix the mold release agent to be used, and the mold release agent adhering to the molded product causes the surface of the molded product to be rough or to have a complicated shape. There is a problem that skill is required to uniformly apply the release agent to the mold.

Also disclosed is a method of using zinc stearate as an internal mold release agent (JP-A-60-245622). However, zinc stearate has poor solubility in polyols and will settle and separate if left at room temperature. In order to improve the compatibility with the polyol, it is added to the polyol after being mixed with the amine compound, but it has a drawback that preparation of the raw material is troublesome, and the release property is also required to be improved.

[0006]

In the production of polyurethane and / or polyurea moldings, the stability, physical properties, mold releasability and paintability of the polyol solution are excellent even when an internal mold release agent is added, and the bleeding phenomenon occurs over time. As a result of earnest studies on an internal mold release agent having a small amount, the present invention has been found to achieve the object by using a specific aliphatic ketone, and has reached the present invention.

[0007]

Means for Solving the Problems That is, the present invention comprises (a) an organic polyisocyanate, (b) a polyol and / or a polyamine, a chain extender (c) an internal mold release agent (d) a foaming agent if necessary. (C) is an aliphatic symmetric ketone having 10 to 50 carbon atoms or 10 to 25 carbon atoms in the production of a polyurethane and / or polyurea molded article by reaction injection molding using a polyol mixed solution containing an agent and an auxiliary agent. And a carbonyl group contained in the aliphatic asymmetric ketone and the aliphatic asymmetric ketone is 1 or more. (C) is a method for producing a polyurethane and / or polyurea molded article having excellent self-releasing properties, characterized in that 0.05 to 10.0% by weight of the polyol mixture is used.

The organic polyisocyanate (a) used in the present invention includes aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates and the like. For example, diphenylmethane diisocyanate (MD
I), polymethylene polyphenylene polyisocyanate, tolylene diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, methylene bis (cyclohexyl isocyanate), hexamethylene diisocyanate and the like. Polymeric polyisocyanate having a polyisocyanate having an isocyanate group obtained by the reaction of the diisocyanate polymer or a bifunctional or higher-functional polyol with the diisocyanate compound and the polymer, polyol adduct of isocyanate, uretdione, isocyanurate, A carbodiimide modified product and the like are also included.

Known polyols can be used as the (b) polyol used in the present invention. A polyether polyol obtained by addition polymerization of cyclic ethers using water, polyhydric alcohol, polyhydric phenol, alkanolamine, mono- or polyamine, etc. as an initiator is preferable. The number of functional groups of this polyether polyol is preferably 2-8, more preferably 2-3.

As the polyhydric alcohol as the initiator,
Ethylene glycol, propylene glycol, diethylene glycol, glycerin, trimethylolpropane,
Examples include hexanetriol, diglycerin, pentaerythritol, methylglycoxide, dextrol, sorbitol, sucrose and the like. Examples of the polyhydric phenol as an initiator include phenol-aldehyde initial condensate, bisphenol A, bisphenol F and the like.

Examples of the alkanolamine as the initiator include monoethanolamine, diethanolamine, triethanolamine and diisopropylamine, and examples of the mono- or polyamine include aniline, diaminodiphenylmethane, tolylenediamine and ethylenediamine. Examples of cyclic ethers include ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin and halogen-substituted compounds thereof. As the polyamine (b) of the present invention, known ones can be used. Some of the above polyether polyols are aminated, preferably having 2 or more functional groups and a molecular weight of 200 to 5,000, but not limited thereto.

Examples of the chain extender (b) used in the present invention include active hydrogen compounds such as polyhydric alcohols, alkanolamines, polyether polyols, aromatic polyamines and aliphatic polyamines. Preferred chain extenders are those having two or more active hydrogen groups among the above compounds and having a molecular weight of 500 or less. For example, polyhydric alcohols include ethylene glycol, 1,4-butanediol, propylene glycol, diethylene glycol, dipropylene glycol, glycerin, and trimethylolpropane alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, diisopropanolamine, and N. -Alkyl-substituted diethanolamine, 1-methyl-3,5-diethyl-2,4-diaminobenzene as aromatic polyamine, 1
-Methyl-3,5-diethyl-2,6-diaminobenzene, 1,3,5-triethyl-2,6-diaminobenzene, 3,5,3 ', 5'-tetraethyl-4,4'-diaminodiphenylmethane , 3.5-diethyl-2,4-
Examples include a mixture of 8: 2 diamiotoluene and 3,5-diethyl-2,6-diaminotoluene (DETDA).

The internal release agent (c) used in the present invention is a ketone compound containing a long-chain alkyl group and has a symmetrical or asymmetrical structure. The lipophilic group of the aliphatic symmetrical ketone has 10 to 50 carbon atoms and contains one or more carbonyl groups. For example, di-n-hexyl ketone, di-n-heptyl ketone, di-n-octyl ketone, di-n-nonyl ketone, di-n-undecyl ketone, di-n-tridecyl ketone, di-n-pentadecyl. Examples include ketones, di-n-heptadecyl ketone, 5,7-undecanedione, and 8,10-octadecyldione.

The carbon number of the lipophilic group of the aliphatic asymmetric ketone is 1
It has 0 to 25 and contains one or more carbonyl groups. For example, methyl-n-nonyl ketone, methyl-n-
Decyl ketone, methyl-n-undecyl ketone, methyl-n-dodecyl ketone, methyl-n-tridecyl ketone, methyl-n-tetradecyl ketone, methyl-n-pentadecyl ketone, methyl-n-hexadecyl ketone,
Methyl-n-heptadecyl ketone, 2,4 undecanedione, 2,4-tridecanedione, 2,4-octadecyldione and the like can be mentioned.

These release agents are also used as external release agents.
It can also be used as an internal mold release agent, and when used as an internal mold release agent, it is 0.5 to
10.0% by weight is used. Further, the conventional metal salt-based internal mold release agent does not exhibit a mold release effect unless a solubilizing agent is required, but the internal mold release agent of the present invention exhibits a mold releasing effect without requiring a solubilizing agent. Demonstrate.

As the foaming agent (d) and auxiliary agent that can be used as required in the present invention, there are two kinds of foaming agents, an inert low-boiling solvent and a reactive foaming agent.
Examples thereof include methylene chloride, methylene trichloride, trichlorofluoromethane, dichlorodifluoromethane, acetone, hexane and the like, and also nitrogen gas, air and the like. Examples of the latter include water, and include those that generate gas by decomposing at a temperature higher than room temperature, such as azo compounds.

Further, as the auxiliary agent (d), there are a foam stabilizer and a catalyst, and as the foam stabilizer, for example, an organopolysiloxane, an organopolysiloxane-polyoxyalkylene copolymer, and a polyoxyalkylene side chain are included. Examples include silicone-based surfactants such as polyalkenyl siloxanes, and cationic, anionic, nonionic surfactants.

As the catalyst, for example, triethylamine,
Amines such as triethanolamine, diethanolamine, diethylmonoethanolamine, tetramethylethylenediamine, tetramethylpropanediamine, tetramethylhexanediamine, pentamethyldiethylenetriamine, for example stannas octoate, dibutyltin dilaurate, dibutyltin diacetate, dimethyltin. Conventional organic metal compounds such as methylcaptide, dibutyltin mercaptide, tetrabutyl-1,3-diacetoxydistannoxane, tetrabutyl-1,3-dilauroyloxydistannoxane, and carboxylates of tertiary amines Known materials can be used, and a mixture thereof can also be used.

The reaction injection molding is a method in which at least two components of a polyol component and an isocyanate component are prepared, subjected to high pressure collision to form a reaction mixture, and the reaction mixture is filled in a mold to obtain a molded article. The polyol component comprises a polyol and / or a polyamine, a chain extender, an internal release agent, and if necessary, a foaming agent and an auxiliary agent.

[0020]

The polyurethane and / or polyurea molded articles obtained by the present invention have excellent moldability by a reaction injection molding machine and exhibit good mold releasability from the mold.
The physical properties and coatability of the obtained molded product are also good.

[0021]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. In Examples and Comparative Examples, "part"
Means all "parts by weight" and "%" means "% by weight". The samples used in Examples and Comparative Examples are as follows. Polyol A: Polyoxypropylene polyol having a hydroxyl value of 28.0. (FA-909; trade name of Sanyo Chemical Industries) Polyamine A: bifunctional amine-terminated polyoxypropylene having an amine value of 56. (D-2000; trade name of Texaco Chemical) Internal mold release agent A: Di-n-heptyl ketone Internal mold release agent B: Di-n-undecyl ketone Internal mold release agent C: Methyl-n-tridecyl ketone Internal release agent C: Methyl-n-tridecyl ketone Internal release agent D: Methyl-n-pentadecyl ketone Internal release agent E: Zinc stearate EDA-p4: N, N-N ', N'-tetrakis (2-
Hydroxypropyl) ethylenediamine. Catalyst A: a 1: 2 mixture of triethylenediamine and dipropylene glycol. Catalyst B: dibutyltin dilaurate.

Isocyanate A: NDI obtained by modifying uretonimine-modified MDI with a liquid isocyanate having an NCO content of 29.1% with a polyoxypropylene polyol having a hydroxyl value of 33 (trade name FA-703; manufactured by Sanyo Chemical Industries).
Liquid isocyanate having a CO content of 22.7%. Isocyanate B: N obtained by modifying MDI with uretone imine
A liquid isocyanate having an NCO content of 16.1% obtained by modifying a liquid isocyanate having a CO content of 29.1% with a polyol A.

(Preparation of Polyol Mixture) Each polyol mixture was prepared by the following method, and its composition is shown in Table 1. Preparation of Polyol Mixture A 100 parts of Polyol A and DETDA were placed in a four-necked flask.
Charge 25 parts and 2 parts of internal mold release agent A to 10 at 80 ° C.
After stirring and mixing for minutes, the internal release agent A was dissolved in the raw material polyol, and then 0.3 parts of the catalyst A and 0.15 part of the catalyst B were added and mixed to prepare a polyol mixed solution A. Preparation of Polyol Mixtures B to F Using the structures shown in Table 1, the same methods as those for the polyol mixture A were prepared.

Preparation of Polyol Mixtures G to I Using the composition shown in Table 1 and using zinc stearate as an internal mold release agent, the same procedure as in the preparation of Polyol Mixture A was conducted at 80 ° C.
After stirring and mixing for minutes, the catalyst shown in Table 1 was added. However, the polyol mixed solution I is the same amount of zinc stearate as the solubilizing agent EDA-
p4 was used.

[0025]

[Table 1]

Example 1 A molded article (W250 × D180 × t3 mm) shown in FIG. 1 was prepared by using a reaction injection molding machine (PU-50 RIM manufactured by Polyurethane Engineering) with isocyanate A as liquid A and polyol mixed liquid A as liquid B. Was molded with NCO index 105. The results are shown in Table 2.

Examples 2 to 6 Example 1 was repeated except that the polyol mixed solution B was used as the solution B.
Molding was carried out in the same manner as in. The results are shown in Table 2.

Comparative Examples 1 to 3 Molded products were obtained in the same manner as in Example 1 using the liquids A and B shown in Table 2. The results are shown in Table 2.

[0029]

[Table 2]

The molded articles obtained in Examples 1 to 6 all showed excellent mold releasability from the mold and had good physical properties and coating properties.

Evaluation of the resins shown in Examples and Comparative Examples is as follows.
The procedure was as follows. Number of continuous demolding: The number of times that D-186 (manufactured by Chukyo Yushi Co., Ltd.) as an external mold release agent is applied to the surface of the mold only for the first time and the molded product can be demolded without breaking. Flexural modulus: According to JIS K-6911. Elongation: According to JIS K-6301. Heat Sag: 10.16 cm (4 inches) overhang,
120 ° C x 1 hr

[Brief description of drawings]

FIG. 1 is an external view of a product.

FIG. 2 is a side view.

FIG. 3 is a sectional view.

Claims (1)

[Claims] 1. (a) an organic polyisocyanate,
Polyurethane and / or polyurea by reaction injection molding using (b) a polyol and / or polyamine, a chain extender (c) an internal mold release agent (d) a polyol mixed solution containing a foaming agent and an auxiliary agent if necessary. In the production of a molded article, (c) is an aliphatic symmetric ketone having 10 to 50 carbon atoms or an aliphatic asymmetric ketone having 10 to 25 carbon atoms, which is contained in the aliphatic symmetric ketone and the aliphatic asymmetric ketone. The carbonyl group is 1 or more. The method for producing a polyurethane and / or polyurea molded article having excellent self-releasing properties, characterized in that (C) is used in an amount of 0.05 to 10.0% by weight based on the polyol mixture.