JPH0318628B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing polyglycidylamino compounds. More specifically, xylylene diamine or bisaminomethylcyclohexane (hereinafter collectively referred to simply as "diamine")
and epihalohydrin in the large presence of water, the resulting polyhalohydrin is dissolved in water, and the polyhalohydrin is dehydrohalogenated in the presence of an alkali in an aqueous solution to form a polyglycidylamino compound (described below). (sometimes referred to as "polyglycidylamine"). The present applicant previously disclosed a method for industrially producing polyglycidylxylylene diamine or polyglycidylbisaminomethylcyclohexane in JP-A-53-119834, JP-A-53-124226 and JP-A-54. - Proposed in Publication No. 128531.
Subsequently, as a result of further intensive research into the manufacturing method of this polyglycidylamine, it was found that in the method of the invention described above, the dehydrohalogenation reaction using an alkali is carried out in an epihalohydrin solution. In the case of dehydrohalogenation using a solid alkali, the reaction system becomes a slurry-like heterogeneous system consisting of an aqueous phase, an epihalohydrin solution phase, and a solid metal halide salt. Therefore, it was found that the speed of the dehydrohalogenation reaction of the polyhalohydrin is greatly influenced by the stirring speed of the reaction system, and that if the stirring is slow, the halogen content in the polyglycidylamine produced may not be reduced. . It is known that the halogen content in polyglycidylamine greatly affects the storage stability and curing characteristics of the polyglycidylamine, as well as the physical properties of the cured product, and it is desirable to reduce the halogen content as much as possible. Therefore, in practice, the dehydrohalogenation reaction is performed using a stoichiometric amount or more of alkali, or the halogenated alkali metal salt precipitated by dehydrohalogenation is separated, and then the dehalogenation reaction is performed again with an alkali. It was necessary to try to reduce the halogen content in the polyglycidylamine produced as much as possible by adding various measures such as carrying out a hydrogenation reaction. The present inventors subsequently investigated the dehydrohalogenation reaction of this polyhalohydrin and found that a polyhalohydrin represented by the general formula (4) is produced by an addition reaction between a diamine and an epihalohydrin. (However, in the formula, A is a phenylene group or a cyclohexylylene group, R is a hydrogen atom or a methyl group,
And X represents a chlorine atom or a bromine atom. ) is water-soluble, and by converting it into an aqueous solution and carrying out the hydrogen halide reaction of the polyhalohydrin in the presence of an alkali in a homogeneous phase, it becomes a light-colored product in a short time and without being affected by the stirring speed. In addition, it was discovered that polyglycidylamine with extremely low halogen content was produced, and the present invention was achieved. That is, the present invention relates to a method for producing a polyglycidylamino compound that includes the following steps () to () as essential steps in all steps. Step (): Addition reaction of diamine and stoichiometrically excess epihalohydrin in the presence of water, Step (): After completion of the addition reaction, distilling off excess epihalohydrin and water from the reaction mixture, and Step (): A step in which the addition product polyhalohydrin is made into an aqueous solution and the polyhalohydrin is dehydrohalogenated using an alkali in a homogeneous system. According to the method of the present invention, by combining the above three steps, the desired polyglycidylamine can be produced with simpler operations and under easier controllable reaction conditions, and the final product obtained is free from halides. It has practically significant properties such as extremely low content and good storage stability. Hereinafter, each step in the method of the present invention will be explained in detail. First, the step () adopted in the method of the present invention is a step of carrying out an addition reaction between a diamine and an epihalohydrin, and this step itself is taught in the above-mentioned Japanese Patent Application Laid-Open No. 119834/1983. This reaction must proceed satisfactorily at low temperatures in an excess of epihalohydrin, and the presence of water is essential to achieve this objective. By interposing water, the addition reaction is promoted and no crystalline substance is precipitated, so that the desired reaction can be suitably carried out. Incidentally, when a diamine is reacted with an excess amount of epihalohydrin without the intervention of water, a crystalline substance is observed to precipitate in the reaction system at the beginning of the reaction, and this crystalline substance dissolves in the reaction system as the reaction progresses. Of course,
It is known that the dissolution is accompanied by intense heat generation, which causes the addition reaction to run out of control, resulting in undesirable products. In step (), epihalohydrin is used in an amount ranging from 5.5 to 15 mol per mol of diamine.
If the amount is less than the lower limit, it will cause an increase in the viscosity or yellow coloration of the final polyglycidylamine compound, while if it is used in more than the upper limit, there will be no effect, and rather a large amount of energy will be required to distill off the excess epihalohydrin. It is economically disadvantageous because it requires The amount of water to intervene is determined by the amount that can maintain a reaction system in which crystalline substances do not precipitate at the beginning of the addition reaction, or even if crystalline substances precipitate, the reaction temperature can be controlled by the heat generated when it dissolves in the reaction system. Select the lower limit amount by considering the amount that does not make it difficult. On the other hand, the presence of more water than necessary may cause undesirable side reactions and cause deterioration in the quality of the polyglycidylamine compound finally obtained.
Causes loss of epihalohydrin. Therefore,
The amount of water used is 0.5 to 15 per mole of diamine.
Selected within the molar range. Addition is carried out by keeping the mixture of epihalohydrin and water at a predetermined reaction temperature and gradually adding diamine to it while controlling the reaction temperature by removing heat so that the temperature of the reaction system does not exceed 60°C. A method of conducting a reaction is preferred. Although it is necessary to maintain the reaction temperature at 60°C or lower, a range of 20 to 40°C is particularly preferable. Next, step () adopted in the method of the present invention is a step of distilling off the excess epihalohydrin and water used in the above step () from the addition reaction mixture. Step () and step () are characteristic of the method of the present invention, and step () is
This is important as a pretreatment step. The distillation in step () must be carried out under reduced pressure, and the contents of the distillation vessel are preferably kept at a temperature not exceeding 60°C. After most of the epihalohydrin is distilled off, water is newly added to the contents of the distillation vessel, and the remaining epihalohydrin is distilled off azeotropically with water. This is practically preferable because epihalohydrin can be substantially completely eliminated. The polyhalohydrin obtained in step () is
In the following step (), it is made into an aqueous solution. The amount of water to be added is selected based on the amount of diamine as a starting material, and is preferably in the range of 10 to 40 moles per mole of diamine. The lower limit amount is determined by taking into consideration the amount of the halogenated metal salt produced by the dehydrohalogenation reaction that can be completely dissolved in the reaction system. The dehydrohalogenation reaction of the polyhalohydrin in step () can thus be carried out in a homogeneous system, and this homogeneous reaction is an indispensable aspect for achieving the object of the present invention. As the alkali present in the dehydrogenation reaction system, sodium hydroxide is suitable, but potassium hydroxide can also be used, and furthermore, sodium carbonate or potassium carbonate may be used in combination. The form of the alkali used may be solid or an aqueous solution. If an aqueous solution is used, the amount of water used here falls within the limits mentioned above. The amount of alkali used is selected based on the amount of diamine as a starting material, and is 4 to 4 per mole of diamine.
A range of 4.5 moles is preferred. If the amount is less than the lower limit, the dehydrohalogenation reaction will be insufficient and the halogen content in the polyglycidylamino compound produced may increase, which is undesirable.On the other hand, if the amount exceeds the upper limit, the amount of alkali that does not react will only increase. It is also economically unnecessary. The temperature of the dehydrohalogenation reaction is preferably in the range of 20 to 60°C; below 20°C, the reaction may end insufficiently;
C. or higher is not preferable because side reactions such as a reaction between the epoxy group produced in the dehydrohalogenation reaction and water or a reaction between the epoxy group and a terminally reacted halohydrin group tend to occur. The essential steps of the present invention described above (),
The reaction product obtained through steps () and () is a mixture of a polyglycidylamino compound that is substantially insoluble in water and an aqueous solution in which an alkali metal halide salt is dissolved. Although it is possible to separate this mixture and separate the polyglycidylamino compound layer, the reaction mixture is usually separated and purified according to the following operations. That is, the above step ()
An organic solvent that is inert to the polyglycidylamino compound and easily dissolves the polyglycidylamino compound is added to the reaction mixture after the reaction, and the polyglycidylamino compound is dissolved to form an organic solution layer (oil layer). The layer is separated into an aqueous solution layer in which the alkali metal halide salt produced as a by-product in the dehydrohalogenation reaction is dissolved, and the oil layer obtained by separation is purified by washing with water.Finally, the solvent is removed from the oil layer. The desired polyglycidylamino compound is obtained by distilling off the main volatile components. In addition, in these purification steps, oversteps may be incorporated as necessary. The diamine used as a raw material in the method of the present invention is represented by the general formula H ₂ N CH ₂ -A-CH ₂ NH ₂ (1) (wherein A is the same as the definition in formula (4) above). xylylene diamine or bisaminomethylclohexane, in particular metaxylylene diamine or 1,3-bisaminomethylcyclohexane, in an amount not exceeding 40% by weight. It may be used in combination with paraxylylene diamine or 1,4-bisaminomethylcyclohexane. Epihalohydrin has the general formula (However, R and X in the formula are the same as defined in the formula (4) above.) Specifically, epichlorohydrin,
Examples include epibromohydrin and β-methylepichlorohydrin. The polyglycidylamino compound targeted by the present invention has the general formula (However, in the formula, A and R are the same as above.) Refers to a tetraglycidylamino compound represented by the following. The polyglycidylamino compound obtained in this way is an epoxy compound that is liquid at room temperature, and can be cured by adding a curing agent or curing accelerator that is used for ordinary epoxy resins, depending on the selection of the curing agent. It can be made into a heat-resistant and highly rigid cured product. It also has the interesting property of self-curing even when heated without adding a curing agent or curing accelerator. Also, glycidyl ether type epoxy resins synthesized from known epoxy resins such as bisphenol A, bisphenol F, phenol novolak, cresol novolak, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, methylhexahydrophthalic acid. Glycidyl ester type epoxy resin synthesized from aniline, toluidine, phenylene diamine, diaminodiphenylmethane, etc. Glycidyl ether/amine type epoxy resin synthesized from aminophenol, alicyclic epoxy resin It can be used by mixing with resin etc. In particular, when the polyglycidylamino compound of the present invention is mixed with a high-viscosity epoxy resin, the viscosity is reduced and workability is improved, and the physical properties of a cured product that is cured by adding a curing agent or a curing accelerator are improved. Ru. In addition, solid epoxy resins are usually used after being dissolved in a solvent or diluent, unless they are used as a powder, but it is difficult to completely remove the solvent from the cured product, which may cause defects in the cured product. However, by using the polyglycidylamino compound of the present invention, it is possible to obtain a cured product free of such drawbacks. As the curing agent used for curing the polyglycidylamino compound of the present invention, known curing agents can be used, and depending on the required performance or workability, aliphatic amines, aromatic amines, polyamides, acid anhydrides, etc. etc., and modified products thereof can also be used. Furthermore, the polyglycidyl amine compound of the present invention can be blended with reinforcing materials such as glass fibers and carbon fibers, and fillers such as kaolin, silica, and calcium carbonate, as desired. Therefore, the amount added can be increased without deteriorating the physical properties. Other diluents, thickeners, thixotropic agents, plasticizers, flame retardants, coloring agents, etc. may also be added depending on the case. The polyglycidylamino compound of the present invention is particularly useful as a matrix resin for fiber-reinforced resins, and is used for casting, embedding, or impregnation, and is polyfunctional, so it can be used as a crosslinking agent for polymers such as phenol resins, etc. It can also be used as a modifier for unsaturated polyester resins. Next, the present invention will be specifically explained using examples and reference examples. In the examples, "%" is based on weight, and "hydrolyzable chlorine" is a 1/10 N KOH methanol solution at 70°C 15 Amount of chlorine hydrolyzed per minute,
"Storability" refers to the increase in viscosity when polyglycidylamine is stored at 70°C for 10 days compared to its initial value. Example 1 A cooling coil, a stirrer, a nitrogen gas blowing pipe, a thermometer, which can constantly cool the inside of the reactor,
11.1 Add epichlorohydrin (hereinafter abbreviated as ECH) to a reaction vessel equipped with a raw material inlet and pressure reduction piping.
Prepare Kg (120 mol) and water 0.54 Kg (30 mol),
The mixture was heated to 30°C while stirring. Next, 2.04 kg (15 mol) of m-xylylene diamine (hereinafter abbreviated as MXDA) was added dropwise over a period of 1 hour. During the dropping of MXDA, care was taken to avoid heat generation, and cold water was passed through the cooling coil so that the temperature within the reaction vessel was within the range of 30 to 36°C. After the addition was completed, the reaction was continued for another 2 hours at the same temperature to complete the addition reaction. Next, the pressure inside the container was kept at 51 to 53° C. while reducing the pressure, and ECH and water were distilled off over 1 hour. Next, 9.6 kg of water was added into the container, the pressure was returned to normal with nitrogen, and 5.13 kg (61.5 mol) of a 48% caustic soda aqueous solution was added over 40 minutes, and the temperature was desorbed for 1 hour while maintaining the internal temperature at 51 to 54°C. The hydrochloric acid reaction was continued. At that time, the stirring speed was 360 rpm. Next, 11.1 kg of meta-xylene (hereinafter referred to as m-X) was added to the reaction mixture, and the soluble components were dissolved in m-X while cooling to 40°C. Separate the m-X layer and the aqueous layer, add 5000 g of water to the m-X layer, and stir.
The organic layer was separated by standing. Volatile components were distilled off from this organic layer under reduced pressure at a maximum temperature of 136°C for 40 minutes to obtain polyglycidyl metaxylene diamine 5.10
Got Kg. Table 1 shows the analysis results of this polyglycidyl metaxylylene diamine. Example 2 Polyglycidyl metaxylylene diamine was synthesized using the same raw material composition and the same reaction conditions as in Example 1.
However, the stirring speed during the dehydrochloric acid reaction was 120 rpm. Table 1 shows the analysis results of the produced polyglycidyl metaxylylene diamine. Comparative Example 1 Using the same equipment as Example 1, ECH11.1Kg (120
mol) and 540 g (30 mol) of water into the reaction vessel.
Warmed to 30°C. Next MXDA2.04Kg (15mol)
was added dropwise over a period of 1 hour. During the dropping of MXDA, care was taken to avoid heat generation, and cold water was passed through the cooling coil so that the temperature within the reaction vessel was within the range of 30 to 36°C. After the dropwise addition was completed, the reaction was continued for another 2 hours at the same temperature to complete the addition reaction. Next, while keeping the inside of the container at 51-54℃,
5.63 kg (67.5 mol) of a 48% caustic aqueous solution was added over 40 minutes, and the reaction was continued for an additional 3 hours. The stirring speed at this time was 360 rpm. After the reaction is complete,
After adding m-X (11.13 kg) to the mixture and dissolving the soluble components, 5 kg of water was added, the pressure was returned to normal with nitrogen, and after stirring, the mixture was allowed to stand still for liquid separation to separate the organic components. Volatile components were distilled off from this organic material under reduced pressure at a maximum temperature of 120° C. over 1 hour to obtain 5 kg of polyglycidyl metaxylylene diamine. Table 1 shows the analytical values of this polyglycidyl metaxylylene diamine. Comparative Example 2 Polyglycidyl metaxylylene diamine was synthesized using the same raw material composition and the same reaction conditions as in Comparative Example 1.
However, the stirring speed during the dehydrochlorination reaction was 120 rpm.
Table 1 shows the analytical values of the produced polyglycidyl metaxylylene diamine. 【table】

Claims (1)

[Scope of Claims] 1 A diamine represented by the general formula H ₂ NCH ₂ -A-CH ₂ NH ₂ (1) (wherein A represents a phenylene group or a cyclohexylene group); (However, in the formula, R is a hydrogen atom or a methyl group,
After reacting with epihalohydrin represented by In a method for producing an amino compound, (However, in the formula, A and R are the same as above.) () A step of adding diamine and stoichiometrically excess epihalohydrin in the presence of water, () After completion of the addition reaction, removing excess from the reaction mixture. The entire process includes a step of distilling off epihalohydrin and water, and () converting the addition product polyhalohydrin into an aqueous solution and performing a dehydrohalogenation reaction of the polyhalohydrin in a homogeneous system in the presence of an alkali. A method for producing a polyglycidylamino compound, characterized by: