JPS6396178A - Novel production of isocyanurate compound - Google Patents

Abstract

PURPOSE:To obtain the titled compound capable of giving a heat-resistant and nonyellowing urethane substance, by subjecting a diisocyanate, etc. to cyclic- trimerizing polymerization while using a saturated fatty acid metal salt as a catalyst, phosphoric acid esters as a solvent and phosphorous acid esters as a coloring-preventing agent. CONSTITUTION:Hexamethylene diisocyanate and/or a hexamethylene diisocyanate-polyol adduct having terminal isocyanates is polymerized to form isocyanurate in the presence of a saturated fatty acid metal salt expressed by formula I (n is an integer; Me represents metallic sodium or potassium) as a catalyst while using, if necessary, an alcoholic and/or phenolic hydroxy compound, etc., as a promoter, in a solvent of phosphoric acid ester based compound expressed by formula II (R represents alkyl) and using a phosphorous acid ester based compound expressed by formula III (R represents alkyl or phenyl) as a coloring-preventing agent to afford the aimed compound.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides hexamethylene diisocyanate (hereinafter referred to as H
The present invention relates to a method for producing an isocyanurate compound of hexamethylene diisocyanate obtained by cyclic trimerization polymerization of DI (abbreviated as DI) or its urethane modified product.

(Prior art) The urethane compound obtained from HDI is
It is known as a non-yellowing paint with excellent light resistance,
On the other hand, it is inferior in heat resistance compared to urethanized products using aromatic diisocyanates as raw materials, and there is also a problem with the toxicity of I (DI itself).

Therefore, in order to improve these drawbacks of HDI and incorporate isocyanurate rings into a urethane-modified prepolymer that has excellent properties such as non-yellowing, heat resistance, water resistance, and weather resistance, and low toxicity, III is trimerized. The manufacturing method is known.

Generally, isocyanurate conversion of organic isocyanate compounds is known, and various catalysts are used. For example, a method using a tertiary amine (Japanese Patent Publication No. 40-5838)
, a method using acetylacetone metal salt (Japanese Unexamined Patent Publication No. 1983-
69497), Polysulfide Alkali Metal Compounds (Special Publication No. 1973)
-28776), tertiary alkyl phosphine (JP-A-5
8-162623) and the like are known.

However, although these catalysts are effective against aromatic isocyanates, they are less effective against aliphatic diisocyanates.

Among aliphatic diisocyanates, it is particularly difficult to convert HDI into isocyanurate; either the isocyanurate does not proceed at all, or a secondary reaction occurs in parallel with trimerization.
Since this dimer is unstable and easily dissociated, urethane polymers obtained using isocyanurated (IDI) polymers containing it cannot provide the excellent performance of isocyanurate rings. .

Several methods for improving these have been proposed.

For example, a method using a sodium or potassium metal salt of a fatty acid as a catalyst (JP-A-58-162581), a method using a fatty acid zinc as a catalyst (JP-A-6L-42523)
etc.

(Problems to be Solved by the Invention) However, the above method has several problems. In the method disclosed in JP-A-58-162581 in which a sodium or potassium metal salt of a fatty acid is used as a catalyst, the catalyst cannot be dissolved in MDI or HDI and its polyol adduct. Therefore, it is necessary to separate the product and catalyst. Product loss at this time is significant.

This loss can be reduced by reducing the melting medium concentration. One way to reduce this catalyst concentration is to increase the amount of cocatalysts made of alcoholic and/or phenolic hydroxyl compounds, thereby reducing the amount of sodium or potassium metal salts of fatty acids. It is. However, in this method, since the co-catalyst reacts with HDI or its polyol adduct, an increase in the amount of co-catalyst added means a change in the physical properties of the product, which is not preferable.

In addition, Japanese Patent Application Laid-Open No. 61-42523 is a tactile gatsuko or H
DI and sled) are soluble in polyol adducts.

In this case, separation of catalyst and product is very difficult.

If a catalyst is mixed into a product, there are concerns about its impact on its physical properties. Contamination of the catalyst with the product is undesirable.

Furthermore, the products manufactured by these methods (σ) are pale yellow in color, which is a major problem in applications such as paints where the appearance requires IK.

(Means for Solving the Problems) The present inventors have conducted intensive studies to improve these drawbacks, and as a result, have arrived at the present invention. That is, the present invention provides KM for polymerizing hexamethylene diisocyanate and/or terminal isocyanate into hexamethylene sheets, with the formula (I>CnH, n+, cOOMe) as a catalyst.
(I) (wherein n is an integer, straight chain or branched chain,
Me represents sodium or potassium metal. ) In the presence of a saturated fatty acid metal salt represented by s (
[T1 (In the formula, R represents an alkyl group.) A phosphoric acid ester compound represented by the formula (Ill) p(on)s (it) (in the formula, R represents an alkyl group) is used as a or a phenyl group). : Examples of tactile isocyanurate compounds of hexamethylene diisocyanate that can be used in the present invention, which are characterized by being used as layer color inhibitors, include acetic acid, propionic acid,
butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid,
Pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, etc., and sodium or potassium salts of these branched fatty acids. These alkali metal salts other than sodium and potassium HDI
It was not effective for isocyanurating.

As a cocatalyst, a phenolic hydroxy compound or an alcoholic hydroxy compound can be used, whereby the reaction proceeds more easily. Examples of phenolic hydroxy compounds include phenol, cresol, and trimethylphenol, and examples of alcoholic hydroxy compounds include methanol, ethanol, cyclohexanol, and ethylene glycol. Examples of the solvent represented by formula (2) include trimethyl phosphate, triethyl phosphate, and tributyl phosphate.

As the coloring inhibitor represented by formula (IIr), for example,
Trimethyl phosphite, triethyl phosphite, tri-n-phosphite
Butyl, tridecyl phosphite, triphenyl phosphite, etc.

The reaction temperature is preferably 100°C or lower, particularly preferably 30 to 80°C. If the temperature is 100° C. or higher, coloring occurs, which is not preferable.

The reaction time varies depending on the amount of catalyst, reaction temperature, etc.
1 to 4 hours is sufficient. The amount of catalyst varies depending on the amount of co-catalyst and solvent used, but it is 0.001~
Use of 0.05% is sufficient. The amount of phosphoric acid esters used as a solvent is preferably 5 to 50 times the amount of EDI. If the amount is less than this, the effect will not be sufficient, and if it is more than this, it will cause a decrease in the yield of the product, which is undesirable for economic reasons. 0.005 to 1 is preferable with respect to MDI. If the amount is less than this, the effect will not be sufficient, and if it is more than this, the yield may decrease, which is not economically preferable.

Since the decrease in the NGO content as the isocyanurate progresses can be measured by overcurrent analysis, the reaction may be stopped when a predetermined NGO content is reached.

Depending on the NGO content at the time of termination of the reaction, the NCOCO2 content of the isocyanurated HDI polymer can be freely changed.

Terminating agents include acidic compounds such as hydrochloric acid, phosphoric acid, dimethyl phosphate, P-)luenesulfonic acid, benzenesulfonic acid, alkylbenzenesulfonic acid, acetyl chloride, benzoyl chloride, and similar compounds thereof.

The amount of the terminator used is 0.5 to 5 times, preferably 1 to 3 times, per mole of sodium or potassium content in the catalyst.

The obtained reaction product is converted into unformed UE, HDI, etc. by known methods such as extraction and distillation. : An isocyanurate compound can be obtained by removing as much as possible.

Generally, it is preferable that the HDI size in the product is 0.7 weight φ or less in view of its toxicity. In addition, if a product contains a large amount of trimer or higher polycyclic products, it not only causes problems with physical properties such as viscosity and hardness, but also reduces compatibility with solvents and causes cloudiness, so polymerization after distillation The reaction is adjusted using the above terminator so that the NCO group content in the solution is around 20'4C.

HDI content can be measured using a gas chromatography trap.
In addition, the trimer in the product clearly appears near molecule 1504 by liquid chromatography, so it can be
Furthermore, the isocyanurate structure exhibits a clear absorption at 1680 cWt in the infrared absorption spectrum.

The polycyclic compound content can also be determined by a similar method. Moreover, the production of dimer is 178 ocr! in the infrared absorption spectrum! This can be confirmed by absorption of 1.

Furthermore, according to the present invention, it is also a preferable method to perform isocyanurate formation under the same conditions as above using a polyol adduct in which part of HDI is urethanized. As poly-11ol, the molecule f
f13000 or less, using one with 2 to 3 functional groups, HD
Good results can be obtained by using a prepolymer in which 15 mol% or less of the total isocyanate groups form polyol adducts. This can be achieved by adding and carrying out the reaction at a reaction temperature of 100°C or less, preferably 70 to 90°C, for about 2 hours. A temperature of 110° C. or higher is not preferable because the product may be colored or side reactions may occur. As polyols used for urethanization, polyols having a molecular weight of 3000 or less are used.
Trifunctional polyols are suitable, examples of which include as diols ethylene glycol, diethylene glycol, 1,3-butanediol (abbreviated as 1,3-BG), 1
．． Examples of triols include dihydric alcohols such as 4-butanediol, propylene glycol, diethylene glycol, neopentyl glycol, and 1,6-hexane glycol (abbreviated as 1,6-HG), polyester polyols, and polyether polyols. , trihydric alcohols such as glycerin, trimethylolethane, and trimethylolpropane, polyester polyols, and polyether polyols. The polyol may be a mixture of these polyols.

(Effect of the invention) The isocyanurate compound obtained by the method of the present invention is useful not only for paints and adhesives, but also as a raw material for elastomers, plastic foams, etc., and has excellent yellowing resistance, heat resistance, water resistance, weather resistance, etc. Demonstrates excellent performance.

(Example) The present invention will be further described below with reference to Examples, but the present invention is not limited thereto.

Example 1 A 500-40 glass flask equipped with a thermometer, a stirrer, and a nitrogen seal tube was charged with 100 parts of KHDI.
3.4 parts of G and 2 parts of trimethyl phosphate were added, the air in the flask was replaced with nitrogen, and the reaction was carried out at about 70°C for 2 hours. The amount of NGOG was measured and found to be 37.8%. The resulting reaction solution containing 1,3-BG adduct gold was a colorless and transparent liquid.

After cooling the reaction solution to about 60°C, potassium caprate
, oos part, 0.10 part of phenol, and 0.10 part of triphenyl phosphite were added, and the reaction was carried out at about 60°C for 4 hours. To this anti-Cm, 0.00 phosphoric acid was added as a reaction terminator.
35 parts were added and further stirred at this reaction temperature for about 1 hour. The product was a clear colorless liquid. After filtering this liquid and separating the catalyst, it was separated into free M using a thin film distillation apparatus.
DI was distilled off.

The obtained liquid was colorless and transparent, and its NCOCO2 content and free HDI were as shown in the table.

In the IR spectrum of this liquid, a strong absorption characteristic of the isocyanurate group is seen at 1680, and a strong absorption characteristic of the dimer is observed at 17.
Absorption at 80 m was not observed at all.

Example 2 The same method as in Example 1 was carried out using 0.01 part of potassium acetate as a catalyst and 0.15 parts of trimethyl phosphite as a coloring inhibitor. The results are shown in the table.

Example 3 20 parts of tributyl phosphate in solvent, 1°3- in polyol
B G 0.8 parts; potassium myristate 0.
The process was carried out in the same manner as in Example 1 using 0.1 part of tridecyl phosphite and 0.10 parts of tridecyl phosphite as the coloring inhibitor. The results are shown in the table.

Comparative Example 1 Example 1 was carried out without using a coloring inhibitor. The resulting product was pale yellow in color. The results are shown in the table.

Comparative Example 2 Example 1 was carried out without using a solvent. From the results of the engineering R spectrum, no isocyanurate formation was observed. , the results are shown in the table.

Procedural Amendment Show + 1 December 16, 1J61 Mr. Akio Kuroda, Commissioner of the Special Budget Agency, 14 yen indication Patent Application No. 1983-241225 2 Title of Invention: Novel manufacturing method for isocyanurate analogs 5 Amendment case and Relationship/Percentage Applicant (003) Asahi Kasei Kogyo Co., Ltd. 4 Agent Postal code 105 5th floor, Toranomon Sangyo Building, 2-29 Toranomon-ku, Toranomon-ku, Tokyo Prefecture I? IF Claims Column 6: The description of the amendment is amended as follows.

+11 The scope of claims is amended as shown in the attached sheet.

(2) 12th Tei 13th line "1.3-BO2, 4 parts" Correct it to "1, 5-BG 5.5 parts".

(3) Page 15 19 Bamboo f-3-nco, part a” l-3-BGl, 0 parts”.

Hexamethylene diisocyanate and/or copolymer are used as catalysts in the isocyanurate polymerization of the hexamethylene diisocyanate polyol adduct of the terminal isocyanate.
Can be an integer, straight chain or branched.

Me represents sodium, and Me represents potassium. VC in the presence of a saturated fatty acid metal salt represented by PO(OR)! (11
) (In the formula, R represents an alkyl group.) Phosphate ester conversion represented by the formula -=mt is used as a bath agent, and further, the formula (un) P(OR)s (Lll) (in the formula,
R represents an alkyl group or a phenyl group. ) A method for producing an isocyanurate compound of hexamethylene diisocyanate, characterized in that a sulfurous acid ester compound represented by the following formula is used as a coloring inhibitor.

Claims (1)

[Claims] In the isocyanurate polymerization of hexamethylene diisocyanate and/or a hexamethylene diisocyanate polyol adduct of a terminal isocyanate, the formula (I) CnH_2n_+_1COOMe is used as a catalyst.
(I) (where n is an integer and represents a straight or branched chain, and Me represents sodium or potassium metal) in the presence of an alcoholic and/or or at least one compound selected from the group consisting of phenolic hydroxy compounds is used as a promoter, and is represented by the formula (II) PO(OR)_3(II) (wherein R represents an alkyl group) A phosphoric acid ester compound is used as a solvent, and a phosphorous acid ester compound represented by the formula (III) (in the formula, R represents an alkyl group or a phenyl group) is further used as a coloring inhibitor. A method for producing an isocyanurate compound of hexamethylene diisocyanate.