JPS625151B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for liquefying a maleic anhydride adduct of alloocimene which is solid at room temperature. Generally, the addition reaction product of alloocimene and maleic anhydride is often solid at room temperature, and in order to use it as an epoxy resin curing agent, it is desirable to liquefy it. Thus, it is necessary to liquefy the maleic anhydride adduct of alloocimene, which is solid at room temperature. An object of the present invention is to provide a processing method for easily and industrially advantageously liquefying a maleic anhydride adduct of allocimene, which is solid at room temperature. The following method is known as a method for liquefying a solid maleic anhydride adduct of alloocimene. For example, British Patent No. 906017 describes that a maleic anhydride adduct of allocimene is liquefied by thermal isomerization by heat treatment at a temperature of 190 to 240° C. for a long time. However, such an isomerization method by heating for a long time causes thermal decomposition even when carried out in a nitrogen stream, so that the yield of the maleic anhydride adduct of liquid alloocymene obtained after distillation purification is low. In addition, even if the distilled product is temporarily liquid, crystals often precipitate after 2 to 3 days, and even if it is liquid at room temperature, it crystallizes at a low temperature of about 0 to 10 degrees Celsius. do. Example 6 of the same specification states that when a maleic anhydride adduct of alloocimene is heat-treated at 210 to 220°C for 14 hours, the product crystallizes if left to stand; It is stated that when heated, a liquid material was obtained that did not crystallize even if left at room temperature. A method in which liquefaction can only be achieved by such a long heat treatment is extremely disadvantageous industrially. In addition, US Pat. No. 3,078,235 describes a cured epoxy resin prepared by blending and liquefying a solid maleic anhydride adduct of alloocimene, a solid maleic anhydride adduct of myrcene, and hexahydrophthalic anhydride. Although such agents have been proposed, blending and liquefying materials that are solid at room temperature requires a melt-mixing process, which has the drawback of increasing costs. In order to improve these drawbacks, the present applicant previously provided a method in which a maleic anhydride adduct of dimethyloctatriene, such as alloocimene, which is solid at room temperature, is liquefied by heat treatment in the presence of an alkali iodide ( (See specification of Japanese Patent Application No. 103230/1983). after that,
When we investigated various compounds other than alkali iodide, we discovered that a certain compound had the same function as alkali iodide, and completed the present invention. That is, the present invention provides a method for liquefying a maleic anhydride adduct of alloocimene, which is solid at room temperature, by heat-treating it in the presence of a compound selected from the following groups (a) to (c). . (a) A phosphorus element-containing organic compound selected from phosphine compounds and quaternary phosphonium salts (b) An alkali metal salt selected from alkali metal chlorides, thiocyanates, and acetates (c) Magnesium oxide. In this way, the maleic anhydride adduct of alloocimene that is solid at room temperature (hereinafter referred to as "alloocimene maleide") can be prepared by simply adding it to the presence of a compound selected from groups (a) to (c) above. It can be easily liquefied simply by heat treatment. It is assumed that this liquefaction is caused by the isomerization reaction of alloocymene maleide to produce several isomers, and the coexistence of these several isomers lowers the freezing point, but the details are unknown. There are many parts. Alloocimene used in the present invention can be easily obtained by thermal isomerization reaction of α-pinene and the like. Alloocimene obtained by thermal isomerization reaction of α-pinene exists in two types of isomers: trans-cis and trans-trans, and commercially available products usually contain 50 to 50 trans-cis isomers. 70% and 30-50% trans-trans isomers. If maleic anhydride is added to such alloocimene by a Diels-Alder reaction, it will easily become an alloocimene maleate. The alloocymene maleate obtained by this method is
It is usually a mixture of the following two types of isomers, has a melting point of 70°C or higher, for example 83 to 84°C, and is solid at room temperature. (a) used as a compound (hereinafter referred to as "isomerization catalyst") that exists when solid alloocymene maleate is liquefied in the method of the present invention;
The compounds of group (b) are detailed below. The phosphine compound in (a) has the general formula [In the formula, R ₁ , R ₂ , and R ₃ are an alkyl group, a cycloalkyl group, an aryl group, an alkaryl group, or an arylalkyl group having ₁ to 25 carbon atoms;
R ₂ and R ₃ may be the same or different. ] Compounds represented by, for example, trimethylphosphine, triethylphosphine, triisopropylphosphine, tri-n-butylphosphine,
Triisobutylphosphine, tri-sec-butylphosphine, tris-2-ethyl-hexylphosphine, trioctylphosphine, triotadecylphosphine, butyldiphenylphosphine,
Methylbutyloctylphosphine, dimethyloctylphosphine, triphenylphosphine, tricyclohexylphosphine, tribenzylphosphine, benzyldimethylphosphine, Tris-2
-phenylethylphosphine, tricyclopentylphosphine, dimethyllaurylphosphine, tritolylphosphine, tris-P-tert-butylphenylphosphine, and the like. In addition, the quaternary phosphonium salt has the general formula: ( _{In the formula ,} arylalkyl groups, which may be the same or different), such as methyltriphenylphosphonium iodide, ethyltriphenylphosphonium iodide, propyltriphenylphosphonium iodide, n-butyltriphenylphosphonium iodide, enylphosphonium iodide, n-decyltriphenylphosphonium iodide, methyltributylphosphonium iodide, ethyltriphenylphosphonium chloride, n-butyltriphenylphosphonium chloride, ethyltriphenylphosphonium bromide, tetrakishydroxymethylphosphonium chloride, tetra phenylphosphonium chloride, etc. (b) alkali metal chloride, thiocyanate;
Examples of alkali metal salts selected from acetates include chlorides of alkali metals such as lithium chloride, sodium chloride, potassium chloride, rubidium chloride, and cesium chloride; thiocyanates of alkali metals such as sodium thiocyanate and potassium thiocyanate. and alkali metal acetates such as lithium acetate, sodium acetate, and potassium acetate. Among these, phosphine compounds are preferable because they are uniformly dissolved in allocymene maleate, making it easy to adjust reaction conditions, and easy to obtain. The amount of the compounds of the above groups (a) to (c) is 0.005 parts by weight or more, preferably 0.01 to 3.0 parts by weight, based on 100 parts by weight of the alloocymene maleate. These (a) to (c)
The compounds of this group may be added directly to the heated and melted alloocymene maleide, or they may be added to water,
It may be added by other methods, such as by dissolving it in a solvent such as acetone. Furthermore, these compounds supported on a carrier may be packed in a packed column, and the vapor of alloocymene maleate may be passed through the packed bed at a desired reaction temperature to cause the reaction. Regarding the heat treatment conditions in the present invention, if the heating temperature is too low, liquefaction will take a long time, and if the heating temperature is too high, decomposition reactions and reactions to produce resinized products will increase, reducing the yield of the desired liquefied product. The reaction temperature is usually 60-250℃, preferably 100-220℃
It is. In addition, the heat treatment time varies depending on the amount of catalyst and the reaction temperature, and cannot be generally specified, but it is usually 10 minutes to 10 hours, preferably 0.5
~3 hours. As mentioned above, the isomerization catalysts of groups (a) to (c) are supported on a carrier such as pumice, activated carbon, diatomaceous earth, silica gel, molecular sheep, etc., and placed in a column filled with this supported catalyst. The heat treatment can be carried out continuously by passing the vapor of alloocymene maleide at a predetermined reaction temperature, but in such a case, the heat treatment is carried out for a short time at a high temperature of 200 to 250°C. The isomerized liquid product itself is stable, but after being heated and denatured in the presence of a compound selected from the above groups (a) to (c), it is further heated with an acidic catalyst (however, the above (a) The liquid stability can be further improved by adding a phosphorus-containing organic compound) or a noble metal catalyst and denaturing it by heating. Examples of acidic catalysts for this second stage isomerization include polyphosphoric acid, ethyl ether salt of boron trifluoride, phosphorus pentoxide, sulfuric acid, phosphoric acid, phosphorus oxychloride, phosphorus pentachloride, acidic sodium sulfate, pyrophosphoric acid, Metaphosphoric acid, pyrosulfuric acid, chlorosulfonic acid,
Silica, alumina, acidic ion exchange resin, aromatic sulfonic acid, acid clay, activated clay, aluminum chloride, titanium tetrachloride, tin chloride, boron trichloride, etc., and noble metal catalysts include rhodium, ruthenium, palladium, etc. Can be mentioned. In addition, the heat treatment conditions for this second stage isomerization are as follows:
If the heating temperature is too low, liquefaction will take a long time, and if the heating temperature is too high, decomposition reactions and resin formation reactions will increase, reducing the yield of the desired liquefied product.
The reaction temperature, reaction time, and amount of catalyst vary depending on the type of catalyst, so general regulations cannot be given, but the second stage reaction temperature is usually 50 to 250°C, preferably 100°C.
~220℃. Heat treatment time is 5 minutes to 8 hours.
Preferably it is 0.5 hours to 5 hours. In addition, in the case of a noble metal catalyst, the amount of catalyst is
The amount is 0.001 parts by weight or more per 100 parts by weight, 1 to 15 parts by weight for ion exchange resins, silica, alumina, etc., and 0.1 to 5 parts by weight for other acidic catalysts. In addition, alloocimene maleide can be treated with sulfuric acid or
Even when heated in the presence of only an acidic catalyst such as BF ₃ ether salt, alloocymene maleate does not liquefy and remains solid. The product obtained by processing according to the method of the present invention can be used as an epoxy resin curing agent as it is, but in order to obtain an excellent cured product, after washing with water,
Distillation is preferred. Alternatively, the product may be treated with activated carbon for decolorization, addition of a super-aid such as diatomaceous earth, and further treated with a suitable dehydrating agent to remove water, followed by filtration and distillation. Since the liquid product obtained by the method of the present invention is liquid at room temperature, it can be used as an acid component for epoxy resin curing agents, alkyd resins, and unsaturated polyester resins. In addition, this product can be modified into amides, imides, esters, chlorine adducts, alkylene oxide adducts, etc. and used as rust preventive agents.It can also be used as a base oil for grease as magnesium and aluminum salts, and as a diester for rubber. It can also be used as a plasticizer for resins (especially vinyl chloride). In particular, this liquid product may contain various epoxy resins, such as those described in Chapters 3 and 4 of "Epoxy Resins" edited by Hiroshi Kakiuchi and published by Shokodo on September 30, 1971. It exhibits excellent curing performance when used as a curing agent for various epoxy resins. When this liquid product is used as an epoxy resin curing agent, the amount used is usually 60 to 170 parts by weight, preferably 80 parts by weight, per 100 parts by weight of the epoxy resin.
~140 parts by weight. Furthermore, when this liquid product is used as an epoxy resin curing agent, other curing agents such as acid anhydride curing agents may be used in combination as necessary. For example, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyl nadic anhydride, phthalic anhydride, pyromellitic anhydride, dodecynylsuccinic anhydride, nadic anhydride and chlorendic anhydride, myrcene anhydride. Examples include maleic acid adducts and maleic anhydride adducts of terpinene. These acid anhydrides are used in an amount of 10 to 500 parts by weight, preferably 30 to 300 parts by weight, per 100 parts by weight of the liquid alloocymene maleate. In addition, the respective maleic anhydride adducts of myrcene and terpinene can also be blended by blending myrcene or terpinene with alloocimene when reacting alloocimene with maleic anhydride, and reacting this with maleic anhydride. I can do it. Furthermore, when this liquid product is used as an epoxy resin curing agent, a curing accelerator can be used in combination, if necessary. For example, trialkylamine, N-dimethylbenzylamine, triethanolamine, piperidine, dimethylaminomethylphenol, tris(dimethylaminomethyl)phenol, hexoate of tris(dimethylaminomethyl)phenol, imidazoles (e.g. 2-ethyl-4 -methylimidazole), dicyandiamide, triphenylphosphine, etc. can be used in combination as a curing accelerator. The amount of the curing accelerator used is preferably 0.1 to 5 parts by weight per 100 parts by weight of the epoxy resin. In addition, when solid alloocimene maleide is liquefied using the phosphorus element-containing organic compound in (a) and used as a curing agent for epoxy resin without purification such as distillation, the phosphorus element-containing organic compound Since it acts as a curing accelerator for the compound, there is no need to add a new curing accelerator. Next, a description will be given of production examples, examples, and experimental examples of alloocimene maleide. Example of producing alloocimene maleate 686 g (7.0 mol) of maleic anhydride was placed in a 3-capacity four-necked flask equipped with a stirrer, thermometer, condenser, dropping funnel, and nitrogen introduction tube, and 100 c.c. of benzene was added. added. While stirring at room temperature
1000 g (0.735 mol) of alloocimene (manufactured by Yasushi Kogyo Co., Ltd.) was gradually added dropwise. Since the temperature rose due to the heat of reaction, the reaction temperature was maintained at 70-80°C by cooling with a water bath. After about an hour, I finished instilling the alloocimene. Further, in order to complete the reaction, the mixture was stirred at 70 to 80°C for about 1 hour. The reaction solution was red when alloocimene was added dropwise, and turned light brown as the reaction was completed. After the reaction was completed, excess alloocimene and the solvent benzene were distilled off by suction with an aspirator at 100°C or lower (degree of vacuum: 20 mmHg). The alloocimene maleide produced has a melting point of 75-80
It was solid at room temperature. Example 1 60 g of alloocymene maleate obtained above
The mixture was placed in a four-necked flask equipped with a stirrer, thermometer, condenser, and nitrogen gas inlet tube, and heated to 180°C while stirring under a nitrogen gas stream to dissolve.
0.3 g of triphenylphosphine was added to this, and the mixture was further heated to 190°C, and the reaction was continued at the same temperature for 1 hour. Then, under reduced pressure of 0.5 mmHg, a pale yellow fraction of 145-175°C was obtained (yield 90%). The viscosity of this liquefied alloocymene maleate at 25°C was 92 centipoise. Furthermore, this product did not crystallize and remained liquid even after being kept at a temperature of 20°C for two weeks. In addition, 0.1 g of the solid alloocymene maleate obtained in the production example was added to 10 g of this liquid compound, and 5
When it was stored in a constant temperature room at ℃, it crystallized after 3 days. Example 2 Powdered silica/alumina N-631.L was added to 200 g of the liquid alloocymene maleide obtained in Example 1.
(JGC Chemical Co., Ltd. product name, 87% silica, 13% alumina
%) was added and stirred at 180℃ for 4 hours,
Cool to room temperature, then add methyl isobutyl ketone
150 ml was added to filter and separate insoluble components such as silica and alumina, and further, methyl isobutyl ketone in the soluble components was removed using an evaporator. Next, the residue was distilled under reduced pressure at a reduced pressure of 1.5 mmHg.
170g (yield 85%) of a 145-170°C fraction was obtained. The viscosity of this liquefied alloocymene maleate at 25°C was 125 centipoise. Furthermore, this liquid material remained liquid even when stored in thermostatic chambers at 20°C, 50°C, and -20°C for 2 months. Further, 0.1 g of the obtained solid allocymene maleate was added to 10 g of this liquid compound, and the mixture was stored in a constant temperature room at 5° C. for 2 months to maintain its liquid state. Examples 3 to 6 Solid alloocymene maleide obtained in the same manner as in Example 1 except that the type of catalyst, catalyst amount, reaction temperature and time of the phosphorus element-containing organic compound were changed as shown in Table 1. Liquefaction was carried out. The yield of the obtained liquid, its viscosity at 25°C, and its liquid stability when stored for two weeks at room temperature are shown in the same table.

[Table] Example 7 69 g of maleic anhydride was placed in the four-necked flask used in Example 1, and the mixture was stirred under a nitrogen gas flow.
The mixture was heated to a temperature of 140°C, and then, while maintaining the same temperature, a mixture of 50 g of alloocymene and 100 g of α-terpinene with a purity of 50% was added dropwise over an hour.
The mixture was further stirred at the same temperature for 10 minutes. Thereafter, 0.8 g of triphenylphosphine was added into the flask, the temperature was raised to 190°C, and stirring was continued at the same temperature for 30 minutes to complete the isomerization. After the reaction was completed, 145 g (yield: 88%) of a pale yellow fraction with a temperature of 155 to 180°C was obtained under reduced pressure of 0.5 mmHg. The viscosity of this liquid at 25°C was 270°C centipoise. In addition, this liquid material can be used at 20℃, 50℃, -20℃
All of them remained liquid even when stored for two months in a temperature controlled room at ℃. Furthermore, 0.1 g of solid alloocymene maleide was added to 10 g of this liquid compound, and the mixture was heated in a constant temperature room at 5°C for 2 hours.
It remained liquid even after storage for months. Examples 8-9 Isomerization treatment was carried out in the same manner as in Example 7 except that the ratio of alloocymene and α-terpinene was used as shown in Table 2. Stability of the pale yellow liquid obtained at 25°C
The viscosity was measured. The results are shown in Table 2 along with the yield. Examples 10 to 11 Stability of the pale yellow liquid obtained by isomerization treatment in the same manner as in Example 7, except that myrcene with a purity of 75% was used in the ratio shown in Table 2 instead of α-terpinene. The viscosity was measured at , 25°C. The results are shown in Table 2 along with the yield. In addition, each liquid material 10 of Examples 7 to 11 above
0.1 g of solid alloocimene maleate was added to the sample, and the mixture was stored in a constant temperature room at 5° C. for 2 months, and the liquid stability of each product was observed, and all of them remained liquid.

[Table] Examples 12 to 16 Examples except that the compound shown in Table 3 was used in the amount shown in the table instead of 0.3 g of triphenylphosphine, and the isomerization temperature and treatment time were as shown in the table. Solid alloocymene maleide was liquefied in the same manner as in 1, and the viscosity of the obtained liquid at 25°C and the stability of the liquid when stored in a constant temperature room at 20°C for 2 hours were measured. The results are shown in Table 3 along with the yield.

[Table] Example 17 LiCl instead of 0.8g of triphenylphosphine
3.3g, and isomerization conditions: 190℃, 30 minutes at 200℃
A pale yellow liquid material (yield 85%) was obtained in the same manner as in Example except that the temperature was 1 hour. The viscosity of this product at 25°C was 275 centipoise. In addition, this liquid material was heated at 20℃, 5℃,
All of them remained liquid even when stored in thermostatic chambers at -20°C. Further, 0.1 g of solid alloocymene maleate was added to 10 g of this liquid compound, and the mixture remained liquid even when stored in a constant temperature room at 5° C. for 2 months. Example 18 A pale yellow liquid material (yield: 82%) was obtained in the same manner as in Example 17, except that the amounts of alloocymene and α-terpinene were changed to 90 g and 60 g, respectively. this liquid
The viscosity at 25°C was 230 centipoise.
In addition, regarding the liquid stability of the above four items, all of the liquids remained liquid even after two months had passed. Example 19 A pale yellow liquid (yield 88
%) was obtained. The viscosity of this material at 25℃ is 100
It was centipoise hot. In addition, the liquid stability for all four items was 2.
It remained liquid even after months had passed. Example 20 A pale yellow liquid (yield
90%). The viscosity of this material at 25℃ is
It was 120 centipoise. In addition, the liquid stability for all four items was 2.
It remained liquid even after months had passed. Examples 21 to 23 Reisomerization using an acidic catalyst in the same manner as in Example 2, except that the liquid alloocymene maleate obtained in Examples 12, 13, and 16 was used instead of the alloocymene maleate obtained in Example 1. We carried out transformation. The viscosity at 25°C of the obtained liquid compound is shown in Table 4 along with the yield and liquid stability over four items.

[Table] Examples 24 to 26 Various acidic catalysts shown in Table 5 were used as the second-stage isomerization catalyst for 200 g of the liquid alloocymene maleate obtained in Example 1, and the catalyst amount and second-stage isomerization were A liquid product was obtained in the same manner as in Example 2, except that the temperature, time and post-treatment conditions were as shown in the same table. The viscosity of this liquid at 25° C. and the results of a four-item liquid stability test are shown in Table 5 along with the yield.

[Table] Application examples as an epoxy resin curing agent Application examples 1 to 6 100 parts by weight of epoxy resin "Epicote 828" (trade name, manufactured by Ciel Chemical Co., Ltd.: Epoxy equivalent weight 189), 2 parts by weight of benzylmethylamine as a curing accelerator, and curing The liquid alloocymene maleate obtained in each example shown in Table 6 was blended as an agent in the amount shown in the same table, and after stirring and mixing uniformly at room temperature, defoaming was performed under reduced pressure of 2 mmHg or less to obtain an epoxy resin composition. I prepared something. This resin composition was precured at 80° C. for 3 hours, then heated to 120° C., and kept at the same temperature for 6 hours to be completely cured. The physical properties of the obtained cured product are shown in Table 6 along with the viscosity at 25° C. of the epoxy resin composition before curing. For reference, the physical properties of a cured product using commercially available liquid methyltetrahydrophthalic anhydride "HN-2200" (trade name, manufactured by Hitachi Chemical Co., Ltd.) in place of alloocymene maleate are shown in the same table.

【table】

Claims (1)

[Scope of Claims] 1 Maleic anhydride of allocimene, which is characterized by heat-treating a maleic anhydride adduct of allocimene that is solid at room temperature in the presence of a compound selected from the following groups (a) to (c). Method for liquefying acid adducts (a) A phosphorus element-containing organic compound selected from phosphine compounds and quaternary phosphonium salts (b) An alkali metal salt selected from alkali metal chlorides, thiocyanates, and acetates (c) Magnesium oxide. 2 The maleic anhydride adduct of alloocimene, which is solid at room temperature, is heat-treated in advance in the presence of a compound selected from the following groups (a) to (c), and then further heat-treated in the presence of an acidic catalyst. A method for liquefying a maleic anhydride adduct of alloocimene, characterized in that (a) a phosphorus element-containing organic compound selected from phosphine compounds and quaternary phosphonium salts, (b) an alkali metal chloride, thiocyanate, and Alkali metal salt selected from acetate (c) Magnesium oxide.