JP2681597B2 - Method for producing high-functional polyalkylene ether polyol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyalkylene ether polyol having a large number of hydroxyl groups in the molecule. In particular, it is a method for producing a high-functional polyalkylene ether polyol, which is useful as a raw material for a thermosetting resin and is useful for improving performance such as curing property, hardness and heat resistance.

[0002]

2. Description of the Related Art Polyalkylene ether polyols are produced, for example, by adding alkylene oxides to active hydrogen-containing compounds such as polyhydric alcohols, polyhydric phenols, amines and polycarboxylic acids (edited by Keiji Iwata, "Polyurethane"). "Resin Handbook", 100 pages, 1
1987, etc.) and is mainly used as a main raw material for polyurethane resins, polyester resins, etc. The more hydroxyl groups there are, the easier it becomes to have a network structure as the resin skeleton, and the curing property, resin hardness, heat resistance during reaction. It is known that it contributes to the improvement of performance such as property. In addition, the polyalkylene ether polyol thus obtained,
Further, by using diisocyanate, dicarboxylic acid or the like, a polyalkylene ether in which a hydroxyl group is reacted with an isocyanate group or a carboxyl group to add or condense with a bond such as a urethane bond or an ester bond to increase the hydroxyl group content per molecule. It is also conceivable to obtain a polyol.

[0003]

However, in the method of adding alkylene oxide to an active hydrogen-containing compound, the number of hydroxyl groups per molecule of the obtained polyalkylene ether polyol is the number of active hydrogen of the starting material to which alkylene oxide is added. It was determined that there was a problem that the number was usually at most 8 (for example, when sucrose, pentaethylenehexamine and the like were used as starting materials). Further, in the production method in which diisocyanate, dicarboxylic acid and the like are reacted with a polyalkylene ether polyol to bond the molecules, the resulting bond is a urethane bond, a rigid bond such as an ester bond, the viscosity of the resulting polyalkylene ether polyol is There is a problem that it is remarkably increased and is not suitable for use.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies as to a method for producing a highly functional polyalkylene ether polyol having a sufficiently high number of hydroxyl groups per molecule, and as a result,
The present invention has been reached. That is, the present invention has 2 to 8 molecules in the molecule.
A polyol (A) having one hydroxyl group, a monoepoxy monohalogen organic compound (B), and an alkali metal compound (C), wherein (B) is 0.02 per equivalent of the hydroxyl group of (A).
It is a method for producing a polyalkylene ether polyol (D) having a hydroxyl group at the terminal by reacting at a ratio of 0.5 mol.

According to the method for producing a polyalkylene ether polyol of the present invention, the hydroxyl group of the polyol (A) is
Monoepoxy monohalogen An organic group (B) reacts with an epoxy group to form an ether group and a new hydroxyl group, and a hydroxyl group of (A) reacts with a halogen group of (B) to form an ether group. As a result, the polyalkylene ether polyol (D) that does not actually contain an epoxy group and a halogen group is finally obtained. The terminal structure of (D) has the formula, for example, when epihalohydrin is used as (B). [In the formula, R is the residue of the polyol (A), and N is 1 of (A).
The number of hydroxyl groups per molecule].

The polyol (A) having 2 to 8 hydroxyl groups in the molecule of the present invention includes a polyhydric alcohol having a valence of 2 to 8; and the polyhydric alcohol having a valence of 2 to 8; a polyhydric phenol and an amine. Examples thereof include compounds in which an alkylene oxide is added to an active hydrogen-containing compound such as a class.

Examples of the polyhydric alcohol include aliphatic and alicyclic compounds such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, cyclohexanedimethanol and cyclohexylene glycol. Group dihydric alcohols; trihydric alcohols such as glycerin and trimethylolpropane; pentaerythritol;
4 to 8 such as diglycerin, dipentaerythritol, methyl glucoside, sorbitol, glucose and sucrose
Included are alcohols of high valency. Examples of polyhydric phenols include monocyclic dihydric phenols such as pyrogallol, hydroquinone, and phloroglucin; bisphenol A,
Bisphenols such as bisphenol sulfone; phenol novolac and the like. Examples of amines include ammonia; aliphatic monoamines such as C1 to C20 alkylamines; aliphatic polyamines such as ethylenediamine, diethylenetriamine and triethylenetetramine; heterocyclic polyamines such as piperazine and N-aminoethylpiperazine; aniline , Aromatic polyamines such as phenylenediamine, tolylenediamine and xylylenediamine; alkanolamines such as monoethanolamine, diethanolamine and triethanolamine.

Examples of the alkylene oxide added to these active hydrogen-containing compounds include ethylene oxide, propylene oxide, 1,2- or 1,4-butylene oxide and styrene oxide.
Of these, ethylene oxide and propylene oxide are preferable. You may add and use these 2 types together. Also, block addition or random addition may be used.

The addition of alkylene oxide to the active hydrogen-containing compound is usually carried out at 60 to 160 ° C. in the presence of a catalyst or a catalyst (alkali catalyst, amine catalyst, acid catalyst) under normal pressure or pressure. It is carried out at a temperature in one or multiple stages. The number of moles of alkylene oxide added is usually 0.5 to 100 moles per active hydrogen. The alkylene oxide addition polymers can be used as a mixture of two or more, and the number average molecular weight is usually 150 to
10,000. Further, the active hydrogen-containing compound used for obtaining the alkylene oxide addition polymer may be partially used as it is without adding the alkylene oxide.

The monoepoxy monohalogen organic compound (B) in the present invention is an organic compound having one epoxy group and one halogen atom in the molecule. Examples of the monoepoxy monohalogenated organic compound (B) include aliphatic or alicyclic organic compounds containing an epoxy group in which one hydrogen atom is replaced with a halogen atom, and specifically, Epihalohydrins such as epichlorohydrin, epibromohydrin, and 3,4-epoxychlorobutane, 2,3-epoxychlorobutane, 5
-Chloromethyl-1,2-oxocyclohexene and the like can be mentioned. Of these, epihalohydrin is preferable, and epichlorohydrin is particularly preferable.

The alkali metal compound (C) in the present invention
Types of caustic alkali such as sodium hydroxide and potassium hydroxide; metal alcoholates of lower alcohols such as sodium methylate, sodium ethylate and potassium tert-butoxide; alkali metals such as sodium metal and potassium; sodium hydride; Examples thereof include alkali metal hydrides such as potassium hydride. Of these, caustic is preferable, and sodium hydroxide and potassium hydroxide are particularly preferable.

The amount of (B) used is usually 1 hydroxyl group of (A).
It is used when the number of moles of (B) per equivalent is 0.02 to 0.5, preferably 0.05 to 0.25. When the molar ratio of (B) is more than 0.5, the resulting polyalkylene ether polyol (D) has gelation or extremely high viscosity, which makes it difficult to handle when used as a resin raw material. If the molar ratio of (B) is less than 0.02, the average number of hydroxyl groups in one molecule of the resulting polyalkylene ether polyol (D) [number average molecular weight (Mn) and hydroxyl value (OHV by gel permeation chromatography (GPC)] ), The value calculated by OHV × Mn ÷ 56,100] is 10 at most, and the effect of improving physical properties such as cure property, strength, and heat resistance when used as a resin raw material is small.

The amount of (C) used is usually (C) / (B) =
It is used in a molar ratio of 1 to 10, preferably (C) / (B) = 1 to 4. When (C) / (B) is less than 1, the reaction between (A) and (B) does not proceed sufficiently. When it exceeds 10, the excess amount of alkali used in the reaction increases, and the excess amount is not only wasted, but also the labor for removing the excess alkali after the reaction becomes complicated.

Viscosity of the polyalkylene ether polyol (D) obtained in the present invention (value measured by B-type viscometer)
Is usually 5 to 10,000 poise at 25 ° C.
When (A), (B), and (C) are reacted in the above-mentioned use ratio, (D) of 5 to 10,000 poise at 25 ° C. can be obtained. The lower the viscosity is, the more preferable it is for use. When the viscosity at 25 ° C. exceeds 10,000 poise, handling becomes very difficult.

The reaction temperature in the present invention is usually 40 to 1.
The temperature is 50 ° C, preferably 60 to 120 ° C. If the temperature is lower than 40 ° C, the viscosity of the reaction system is high and it is difficult to form a homogeneous mixture system, and the reaction takes a long time. On the other hand, if the temperature exceeds 150 ° C., the ether bond of the polyalkylene ether polyol (D) formed is likely to be decomposed, which is not suitable.

In the present invention, the use of a catalyst can accelerate the reaction. Examples of catalysts that can be used for this purpose include quaternary ammonium compounds, quaternary phosphonium compounds, and metal-based catalysts. Of these, quaternary ammonium compounds are preferable, and examples thereof include benzyltrimethylammonium chloride, tri-n-octylmethylammonium chloride, tetrabutylammonium bromide and tetra-n.
-Butyl ammonium sulfate, tetraethyl ammonium hydroxide and the like.

In the present invention, a solvent can be used if necessary. Suitable solvents are those having no active hydrogen or halogen atom such as ethers, aliphatic hydrocarbons and aromatic hydrocarbons.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Parts and% represent parts by weight and% by weight, respectively.

Example 1 260 parts of sorbitol was reacted with 740 parts of propylene oxide in the presence of a potassium hydroxide catalyst to give a number average molecular weight of 700 by GPC and a hydroxyl value of 480 mgKOH /
A polyalkylene ether polyol having an average number of hydroxyl groups of 6 and a viscosity of 220 poise (25 ° C.) was obtained. 500 parts (0.71 mol) of this polyalkylene ether polyol and 28.4 parts (0.71 mol) of sodium hydroxide, and benzyltrimethylammonium chloride as a catalyst 1.
9 parts (0.01 mol) were charged into a reaction vessel and stirred under a temperature of 80.
The temperature was raised to ° C. Next, 44.4 parts (0.48 mol) of epichlorohydrin was added, and the mixture was reacted at 80 ° C. for about 2 hours. The reaction product was diluted with 500 parts of toluene, sodium chloride and sodium hydroxide were filtered off, and the volatile matter was removed under reduced pressure for purification. Thus, about 420 parts of a viscous brown transparent liquid polyether was obtained. This polyether does not substantially have an epoxy group, has a hydroxyl value of 400 mgKOH / g, a viscosity of 1,400 poise (25 ° C.), and a number average molecular weight by GPC of 2,300.
The average number of hydroxyl groups was 16.4.

Example 2 34 parts of pentaerythritol and 8 parts of propylene oxide
16 parts of ethylene oxide and then 150 parts of ethylene oxide were reacted in the presence of a potassium hydroxide catalyst to give a number average molecular weight of 3,950 by GPC, a hydroxyl value of 57 mgKOH / g and a viscosity of 9
A poise (25 ° C.) polyalkylene ether polyol having an average number of hydroxyl groups of 4 was obtained. Charge 500 parts (0.127 mol) of this polyalkylene ether polyol and 6.6 parts (0.118 mol) of potassium hydroxide to a reaction vessel,
The temperature was raised to 80 ° C. with stirring. Then, 9.1 parts (0.098 mol) of epichlorohydrin was added and reacted at 80 ° C. for about 2 hours. This reaction product was diluted with 500 parts of toluene, potassium chloride and potassium hydroxide produced as by-products were filtered off, and the volatile matter was removed under reduced pressure for purification. In this way, a viscous, slightly yellow transparent liquid polyether about 4
I got 00 parts. This polyether has substantially no epoxy group, a hydroxyl value of 45 mgKOH / g and a viscosity of 6
00 poise (25 ° C), number average molecular weight by GPC is 1
It was 7,500 and the average number of hydroxyl groups was 14.1.

Example 3 360 parts of sucrose was reacted with 640 parts of propylene oxide in the presence of a trimethylamine catalyst to give a number average molecular weight of 950 by GPC and a hydroxyl value of 468 mgKOH / g.
A polyalkylene ether polyol having an average functionality of 8 and a viscosity of 310 poise (25 ° C.) was obtained. 500 parts (0.53 mol) of this polyalkylene ether polyol, 20 parts (0.50 mol) of sodium hydroxide, and 2.25 parts (0.05 mol) of tetrabutylammonium bromide as a catalyst.
(07 mol) was charged into a reaction vessel, and the temperature was raised to 80 ° C. with stirring. Then, 38.9 parts (0.42 mol) of epichlorohydrin was added, and the mixture was reacted at 80 ° C. for about 2 hours. The reaction product was diluted with 500 parts of toluene, sodium chloride and sodium hydroxide were filtered off, and the volatile matter was removed under reduced pressure for purification. In this way, about 425 parts of a viscous brown transparent liquid polyether was obtained. This polyether has virtually no epoxy group and has a hydroxyl value of 407 m.
gKOH / g, viscosity 880 poise (25 ° C.), number average molecular weight by GPC was 4,820, and average number of functional groups was 35.

Comparative Example 1 The same operation was carried out except that the amount of epichlorohydrin added in Example 1 was changed to 94.4 parts (1.02 mol). It became impossible. The obtained high-viscosity substance was a rubber-like polymer at room temperature and was a polymer insoluble in organic solvents such as toluene and methylene chloride.

Comparative Example 2 The amount of epichlorohydrin added in Example 1 was 13 parts (0.1
(4 mol), but the same operation was performed to obtain about 475 parts of a brown transparent liquid polyether. The hydroxyl value of this polyether is 454 mgKOH / g and the viscosity is 350.
Poise (25 ° C), number average molecular weight by GPC is 89
The average number of hydroxyl groups was 0 and 7.2.

Comparative Example 3 260 parts of sorbitol was reacted with 740 parts of propylene oxide in the presence of a potassium hydroxide catalyst to give a number average molecular weight of 700 by GPC and a hydroxyl value of 480 mgKOH /
A polyalkylene ether polyol having an average functionality of 6 and a viscosity of 220 poise (25 ° C.) was obtained. 500 parts of this polyalkylene ether polyol (0.71 mol) and 500 parts of dimethylformamide were charged into a three-necked flask, and 92 parts (0.53 mol) of tolylene diisocyanate was added dropwise at 80 ° C. in about 10 minutes. did. 80 ℃
Mixing is continued for about 3 hours while maintaining the above temperature, 0.05 part of dibutyltin dilaurate (urethane forming catalyst) is added, and further 5 hours 8
After continuing the reaction at 0 ℃, 120 ℃, vacuum degree 30mmHg
Then, dimethylformamide was distilled off to obtain a slightly yellow transparent semi-paste-like polyether. The isocyanate content of the obtained polyether was 0.04% (urethane conversion rate = 98%), the hydroxyl value was 371 mgKOH / g, and the viscosity could not be measured at 25 ° C. (10,000 poise or more), 5
At 0 ° C., 83,500 poise, the number average molecular weight by GPC was 3,700, and the average number of hydroxyl groups was 24.

Comparative Example 4 260 parts of sorbitol was reacted with 740 parts of propylene oxide in the presence of a potassium hydroxide catalyst to give a number average molecular weight of 700 by GPC and a hydroxyl value of 480 mgKOH /
A polyalkylene ether polyol having an average functionality of 6 and a viscosity of 220 poise (25 ° C.) was obtained. 500 parts (0.71 mol) of this polyalkylene ether polyol,
71 parts (0.53 mol) of terephthalic acid and 1.5 parts of paratoluenesulfonic acid were charged into a three-necked flask, and 230
The temperature was raised to ° C. The reaction was carried out for 8 hours while removing generated water under a nitrogen stream to obtain a slightly yellow transparent semi-paste-like polyether. The obtained polyether has an acid value of 1.2 (esterification reaction rate = 99%) and a hydroxyl value of 361 mgKOH /
g, viscosity was not measurable at 25 ° C. (10,000 poise or more), 42,000 poise at 50 ° C., number average molecular weight by GPC was 2,500, and average number of hydroxyl groups was 16.

It can be seen that the polyalkylene ether polyols according to the examples of the present invention have a low viscosity as compared with the comparative examples, although they have more average hydroxyl groups.

[0026]

The polyalkylene ether polyol of the present invention has a remarkably large number of functional groups as compared with conventional ones, and can be easily and inexpensively produced by the production method of the present invention. When the polyalkylene ether polyol of the present invention is used as a raw material for polyurethane resin, polyester resin, epoxy resin and the like, it can be applied to a wide range of fields such as improvement in curing property, resin hardness and heat resistance.

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Claims (6)

(57) [Claims] 1. A polyol (A) having 2 to 8 hydroxyl groups in the molecule, a monoepoxy monohalogen organic compound (B), and an alkali metal compound (C) are added per equivalent of hydroxyl group of (A) ( A method for producing a polyalkylene ether polyol (D) having a hydroxyl group at the terminal by reacting B) in a proportion of 0.02 to 0.5 mol. 2. The average number of hydroxyl groups in one molecule of the obtained polyalkylene ether polyol (D) is 10 to 10.
It is 0, The manufacturing method of the polyalkylene ether polyol of Claim 1. 3. The polyol (A) is an alkylene oxide addition product of an active hydrogen compound.
A method for producing the described polyalkylene ether polyol. 4. The method for producing a polyalkylene ether polyol according to claim 1, wherein the monoepoxy monohalogen organic compound (B) is aliphatic or alicyclic. 5. The method for producing a polyalkylene ether polyol according to claim 1, wherein the monoepoxy monohalogen organic compound (B) is epihalohydrin. 6. The method for producing a polyalkylene ether polyol according to claim 1, wherein the alkali metal compound (C) is a caustic alkali.