JP2001039960A - Water-soluble polyglycidyl ether and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a water-soluble polyglycidyl ether satisfying a cross-linking density and physical properties (especially viscosity) required from various uses. SOLUTION: This polyglycidyl ether is produced by reacting two or more kinds of polyhycric alcohols with an epihalohydrin and cyclizing the resultant halohydrin ether and has the following various characteristics: (1) having >=60% water solubility when converted into a 10% aqueous solution, (2) having <=4,000 cP viscosity at 25 deg.C and (3) containing at least 2 epoxy groups in the molecule and having <=180 molecular weight based on one epoxy group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a water-soluble polyglycidyl ether and a method for producing the same.

[0002]

2. Description of the Related Art Polyglycidyl ethers have hitherto been used in various applications as crosslinking agents. In recent market trends, there is a tendency to desire an aqueous type that does not use an organic solvent from the viewpoint of environmental problems. However, for example, in the field of paints and adhesives, water-based materials are inferior in water resistance to organic ones.

[0003]

That is, there is no polyglycidyl ether satisfying the cross-linking density and physical properties (especially viscosity) required in various applications on the market, and the polyglycidyl ether satisfying the further water solubility is not available. The varieties were limited, which necessitated some compromises in performance and handling. For example, sorbitol polyglycidyl ether is a compound having an ether group, a hydroxyl group, and the like, and is expected as a water-soluble cross-linking agent having excellent cross-linking performance, but has poor workability due to high viscosity. In particular, it was extremely difficult to take them out of the storage container in winter.

A method for producing a halogen-containing polyether / polyepoxide composition by partially cyclizing a polyhalohydrin ether produced by the reaction of a polyhydric alcohol and epihalohydrin is disclosed in US Pat. No. 258,146.
No. 4 is known. Further, in the specification, with respect to poorly soluble high melting point polyhydric alcohols such as pentaerythritol and polypentaerythritol, when reacting with epichlorohydrin, polyhydric alcohols such as ethylene glycol, glycerin, diglycerin, and trimethylolpropane are used. It has been proposed for use as a solvent. At that time, a very complicated composition is formed,
The utility is not harmed. But,
There is no mention of application to a water-soluble crosslinking agent. In particular, it does not describe what composition is suitable for applying a pentahydric or higher polyhydric alcohol glycidyl ether such as sorbitol glycidyl ether to a water-soluble crosslinking agent.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve such problems, and as a result, a polyglycidyl ether composition having specific properties has been found to be soluble in water, handleable, and crosslinked. It was found that a water-soluble cross-linking agent excellent in the above point was provided, and a production method thereof was established.

The gist of the present invention is obtained by ring-closing a halohydrin ether formed by a reaction between two or more polyhydric alcohols and epihalohydrin, and has the following properties: (1) a 10% aqueous solution (2) The viscosity at 25 ° C. is 4000 cp or less, and (3) the molecule contains at least two epoxy groups, and 180 molecular weight
A water-soluble polyglycidyl ether characterized by having the following.

Another gist is that a polyhydric alcohol is added with an epihalohydrin to form a halohydrin ether in the presence of a Lewis acid catalyst, and then the halohydrin ether is brought into contact with a strong alkali to close the ring. In the method for producing glycidyl ether, in the above addition reaction, a) sorbitol and glycerin are used in combination as polyhydric alcohols, and b) glycerin is 20 to 80% by weight in both polyhydric alcohols.
C) The ratio of polyhydric alcohol to epihalohydrin is selected from the range of 0.4 to 1.5 mol of epihalohydrin per equivalent of hydroxyl group of polyhydric alcohol, and d) the reaction temperature is 50. A method for producing a water-soluble polyglycidyl ether, wherein the method is selected from the range of -110 ° C.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The water-soluble polyglycidyl ether of the present invention is obtained by ring-closing a halohydrin ether formed by the reaction of two or more polyhydric alcohols with epihalohydrin. It is a mixture of various compounds. Typically, the starting polyhydric alcohol O
There is a polyglycidyl ether which is formed when epihalohydrin is added to one H group one by one and the ring is closed. Ether, pentaerythritol polyglycidyl ether, dextrose polyglycidyl ether, sorbitol polyglycidyl ether, mannitol polyglycidyl ether and the like. These polyglycidyl ethers actually include compounds in which some of the OH groups of the polyhydric alcohol are not glycidyl etherified. Even in this case, epihalohydrin was added, but ring closure was not performed, some compounds remained as halohydrin ethers, and even epihalohydrin addition reaction was not performed, and some OH groups remained unreacted. There is also a compound of the formula: In addition, the OH group 1 of the polyhydric alcohol
In some cases, glycidyl ethers, which are formed when a plurality of epihalohydrins are added to an individual and only the terminal is closed, are included. Moreover, these various compounds cannot produce only a single compound even by controlling the reaction conditions. Further, the water-soluble polyglycidyl ether of the present invention is a mixture obtained by producing two or more kinds of compounds as described above from two or more kinds of starting polyhydric alcohols.

However, it is possible to obtain a composition having characteristics suitable for a specific application. In the present invention, the following characteristics are provided: (1) The water solubility of a 10% aqueous solution is 60% or more. (2) a viscosity at 25 ° C. of 4000 cp or less; and (3) a molecule containing at least two epoxy groups in the molecule and having a molecular weight per epoxy group (sometimes referred to as epoxy equivalent). ) Is 180 or less.

[0010] Whether or not these characteristics are provided can be easily confirmed by a conventional measuring method. The water solubility is indicated by, for example, the dissolution rate when 10 g of polyglycidyl ether is dissolved in 90 g of water at 25 ° C. The water solubility must be 60% or more, preferably 80% or more, and particularly preferably 90% or more. If the water solubility is too low, the use of an organic solvent is required, which does not solve environmental problems.

The viscosity must be 4000 cp or less at 25 ° C., preferably 3000 cp or less, particularly preferably 500 to 1000 cp. If the viscosity is too high, the workability is reduced, uniform stirring is difficult when mixing with other materials, and even in winter work, it is impossible to take out from the container.

[0012] The number of epoxy groups and the epoxy equivalent are important requirements that determine the crosslinking performance, but are measured here as an average value for a mixture, not for an individual compound, and at least two epoxy groups per molecule. It contains an epoxy group, and the molecular weight per epoxy group needs to be 180 or less, preferably 175 or less, particularly preferably 170 or less. Generally, a structure in which the number of functional groups in one molecule of polyglycidyl ether is large and the molecule is small is effective for increasing the crosslink density.

This provides an important guideline when selecting a starting polyhydric alcohol that forms the core structure of the polyglycidyl ether molecule.
One of the polyhydric alcohols is preferably a pentavalent or higher alcohol, and the other polyhydric alcohol is preferably a trivalent or higher alcohol. In particular,
As pentahydric or higher alcohol, sorbitol, and as trihydric or higher alcohol, glycerin, polyglycerin having an average molecular weight of 500 or less, trimethylolpropane or pentaerythritol,
Particularly preferred.

In the present invention, the halohydrin ether is prepared by adding epihalohydrin to a polyhydric alcohol in the presence of a Lewis acid catalyst. Examples of the Lewis acid catalyst include anhydrous aluminum chloride and boron trifluoride. There are (BF ₃ ), zinc chloride, ferric chloride, stannic chloride and the like, and there is no particular limitation. Usually, a BF ₃ ether complex salt is used.

Thus, in this addition reaction, a) when sorbitol and glycerin are used in combination as the polyhydric alcohol, b) 20-80% by weight of glycerin in both polyhydric alcohols
C) The ratio of polyhydric alcohol to epihalohydrin is selected from the range of 0.4 to 1.5 mol of epihalohydrin per equivalent of hydroxyl group of polyhydric alcohol, and d) the reaction temperature is 50. It is preferable to select from the range of -110 ° C.

That is, when a desired water-soluble polyglycidyl ether is obtained from sorbitol and glycerin, glycerin 20 to 80% by weight in both polyhydric alcohols is used.
Is preferably selected from the range. Particularly preferably,
Glycerin is selected from the range of 30 to 50% by weight. So, if there is too much sorbitol than the above range,
The viscosity of polyglycidyl ether increases, which is not preferable in handling. On the other hand, if the amount of glycerin is too large, the crosslinking performance is undesirably reduced.

The ratio between the polyhydric alcohol and epihalohydrin is preferably selected from the range of 0.4 to 1.5 mol of epihalohydrin per equivalent of hydroxyl group of polyhydric alcohol. Particularly preferably, epihalohydrin is selected from the range of 0.6 to 1.2 mol per 1 equivalent of the hydroxyl group of the polyhydric alcohol. If the proportion of the epihalohydrin is too large, the water solubility decreases, and if the proportion is too small, the crosslinking performance decreases, which is not preferable.

The reaction temperature is preferably selected from the range of 50 to 110 ° C. Particularly preferably, 70 to 100 ° C
Is selected from the range. If the reaction temperature is too high, the epoxy equivalent is reduced and the product is colored. On the other hand, if the temperature is too low, it takes time to complete the reaction, which is not preferable.

The halohydrin ether thus obtained is contacted with a strong alkali to prepare a water-soluble polyglycidyl ether by ring closure. However, in order to avoid a reduction in the purification yield of the water-soluble compound, the halohydrin ether is usually used. An organic solvent is added to carry out a ring closure reaction, the reaction solution is separated into an organic layer and an aqueous layer, and the solvent is removed from the organic layer to obtain a polyglycidyl ether.

In the ring closure reaction, as a strong alkali, caustic soda, caustic potash, calcium hydroxide, sodium carbonate, potash carbonate or the like may be used in the form of a solid or an aqueous solution.
There is no particular limitation as long as a polyglycidyl ether having predetermined characteristics such as a mode of using an alkali metal aluminate, a silicate, a zincate or the like in a solid state can be obtained. Practically, it is preferable to use an aqueous solution of caustic soda or the like in that the reaction can be carefully controlled so that the formed epoxy ring does not open to increase the epoxy equivalent.

[0021]

EXAMPLE 1 210 g of sorbitol was placed in a two-liter four-necked flask having an internal volume of 2 liters.
And glycerin (weight ratio: 50:50), 1 g of BF ₃ ether complex salt (hereinafter abbreviated as boron trifluoride) as a catalyst, and add 1060 g of epichlorohydrin dropwise over 120 minutes while stirring at 70 to 80 ° C. Then, an addition reaction was performed. After completion of the dropwise addition, aging was carried out for 60 minutes until unreacted epichlorohydrin disappeared to obtain chlorohydrin ether. To the obtained chlorohydrin ether, 2960 g of toluene was added, and 954.6 g of a 48% aqueous solution of caustic soda was added at 20 to 30 ° C. over 30 minutes to perform a ring closure reaction. Thereafter, 1512.9 g of water was added to dissolve the precipitated sodium chloride, and the toluene layer was separated by standing separation. Toluene was removed by distillation, and the residue in the kettle was filtered to obtain 760 g of crude polyglycidyl ether.

0.2 g of 75% phosphoric acid was added to 300 g of the crude polyglycidyl ether, followed by stirring at 75 ° C. for 1 hour. Then, Kyowa Chemical Co., Ltd. Kyoward 500SH [Mg ₆ Al ₂ (OH) ₁₆ CO ₃ .4H ₂
O] was added, and the mixture was further stirred at 75 ° C for 1 hour. After the solution was cooled to 50 ° C. or lower, the solution was filtered to obtain 285 g of a product polyglycidyl ether. Table 1 shows the product characteristics.
As shown in FIG.

Example 2 In Example 1, the amounts of the raw materials and the catalyst used in the addition reaction were changed to 260 g of sorbitol and 174.2 g of glycerin.
(Weight ratio: 60:40) A product polyglycidyl ether was obtained in the same manner as in Example 1 except that boron trifluoride was changed to 1.1 g and epichlorohydrin to 1053 g. Its characteristics are as shown in Table 1.

Example 3 In Example 1, the amounts of the raw materials used for the addition reaction were changed to 300 g of sorbitol and 129 g of glycerin (weight ratio: 7).
0:30), and a product polyglycidyl ether was obtained in the same manner as in Example 1 except that epichlorohydrin was changed to 998.5 g. Its characteristics are as shown in Table 1.

Comparative Example 1 In Example 1, the amounts of the raw materials and the catalyst used in the addition reaction were 491.8 g of sorbitol and 54.6 of glycerin.
g (weight ratio 90:10), boron trifluoride 1.3 g, and epichlorohydrin 1165.9 g, except that the product polyglycidyl ether was obtained in the same manner as in Example 1. Its characteristics are as shown in Table 1.

Comparative Example 2 In Example 1, the amounts of the raw materials and the catalyst used in the addition reaction were 400 g of sorbitol, 0.9 g of boron trifluoride,
A product polyglycidyl ether was obtained in the same manner as in Example 1 except that epichlorohydrin was changed to 1219.0 g and the reaction temperature was changed to 90 to 100 ° C. Its characteristics are as shown in Table 1.

Comparative Example 3 In Example 1, the amounts of the raw materials and the catalyst used for the addition reaction were 54.6 g of sorbitol and 491.8 of glycerin.
g (weight ratio 10:90), boron trifluoride 1.3 g, and epichlorohydrin 1591.5 g, in the same manner as in Example 1 to obtain a product polyglycidyl ether. Its characteristics are as shown in Table 1.

Comparative Example 4 In Example 1, the amounts of the raw materials and the catalyst used for the addition reaction were 497.2 g, 99.5 g of polyethylene glycol (average molecular weight: 200), 1.4 g of boron trifluoride, and epichlorohydrin 1102. Except having changed to 6 g, it carried out similarly to Example 1, and obtained the product polyglycidyl ether. Its characteristics are as shown in Table 1.

Comparative Example 5 In Example 1, the amounts of the raw materials and the catalyst used in the addition reaction were changed to 400 g of pentaerythritol, 1.7 g of boron trifluoride, and 1466.0 g of epichlorohydrin, and the reaction temperature was 90 to 100 ° C. In the same manner as in Example 1 except that the product was changed to, a product polyglycidyl ether was obtained. Its characteristics are as shown in Table 1.

[0030]

[Table 1]

[0031]

According to the present invention, a water-soluble polyglycidyl ether which can be applied to various uses as a crosslinking agent having excellent water solubility, viscosity and crosslinking performance can be obtained.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koji Mase 710, Rokomicho, Yokkaichi-shi, Mie Yokkaichi Gosei Co., Ltd. F-term (reference) 4C048 AA01 BB09 CC02 CC03 UU05 XX02 XX04 4J036 AB02 AB03 BA01

Claims (6)

[Claims] 1. A halohydrin ether formed by the reaction of two or more polyhydric alcohols with epihalohydrin, which is obtained by ring-closing, and has the following properties: (1) water solubility in a 10% aqueous solution Is not less than 60%, (2) the viscosity at 25 ° C. is not more than 4000 cp, and (3) the molecule contains at least two epoxy groups, and the molecular weight per epoxy group is 180.
A water-soluble polyglycidyl ether, comprising: 2. The water-soluble polyglycidyl ether according to claim 1, wherein one of the polyhydric alcohols is a pentahydric or higher alcohol. 3. The water-soluble polyglycidyl ether according to claim 2, wherein one of the polyhydric alcohols is sorbitol. 4. The water-soluble polyglycidyl ether according to claim 1, wherein the other polyhydric alcohol is a trihydric or higher alcohol. 5. The polyhydric alcohol further comprises glycerin,
The water-soluble polyglycidyl ether according to claim 4, wherein the water-soluble polyglycidyl ether is selected from polyglycerin having an average molecular weight of 500 or less, trimethylolpropane, and pentaerythritol. 6. A process for producing a water-soluble polyglycidyl ether in which a polyhydric alcohol is added with epihalohydrin in the presence of a Lewis acid catalyst to form a halohydrin ether, and then the halohydrin ether is brought into contact with a strong alkali to close the ring. In the above addition reaction, a) sorbitol and glycerin are used in combination as the polyhydric alcohol;
C) The ratio of polyhydric alcohol to epihalohydrin is selected from the range of 0.4 to 1.5 mol of epihalohydrin per equivalent of hydroxyl group of polyhydric alcohol, and d) the reaction temperature is 50. A method for producing a water-soluble polyglycidyl ether, wherein the method is selected from the range of -110 ° C.