Method for producing benzoxazine compounds

Abstract

To provide a new production method for a benzoxazine compound that is excellent in reaction time, product yield, and environmental load.SOLUTION: A method for producing a benzoxazine compound according to an embodiment includes a reaction step for heating a mixture of phenol, a predetermined diamine, and paraformaldehyde for a reaction, the mixture having a solid content of 80-100 wt.%.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a benzoxazine compound. [Background technology]

[0002] Conventionally, benzoxazine compounds have been mainly synthesized by a method using a solution (a solution method).

[0003] For example, Patent Document 1 discloses a method for producing a compound having a dihydrobenzoxazine ring, in which a mixture of a specific bisphenol compound and formaldehyde is reacted with a primary amine while being gradually added thereto.

[0004] Furthermore, Patent Document 2 discloses a production method in which a specific bisphenol compound, paraformaldehyde, and an amine compound are mixed and heat-treated in the presence of a specific solvent.

[0005] Furthermore, Non-Patent Document 1 discloses a method for producing polybenzoxazine, in which a diamine and a phenol are reacted in toluene / ethanol.

[0006] On the other hand, there are also methods for producing benzoxazine compounds without using a solvent. For example, Patent Document 3 discloses a method for producing a benzoxazine monomer using phenol, paraformaldehyde, and m-cresol as substrates. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2004-217941 A [Patent Document 2] JP 2012-126900 A [Patent Document 3] US Patent Publication No. 2017 / 0166537 [Non-patent literature]

[0008] [Non-Patent Document 1] Sarychev et al. "Benzoxazine monomers based on aromatic diamines and investigation of their polymerization by rheological and thermal methods" J Appl Polym Sci. 2020 Summary of the Invention [Problem to be solved by the invention]

[0009] However, the above-mentioned method for producing benzoxazine-based compounds has room for improvement in terms of reaction time, product yield, and environmental load.An embodiment of the present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide a new method for producing benzoxazine-based compounds, which has a shorter reaction time than conventional production methods, a yield of benzoxazine-based compounds equal to or greater than conventional production methods, and a lower environmental load because the present production method uses less solvent than conventional production methods that use solvent. [Means for solving the problem]

[0010] As a result of intensive research to solve the above problems, the present inventors have found that a benzoxazine compound can be produced by a method that is superior in reaction time, product yield, and environmental impact to conventional methods by reacting phenol, a diamine having a specific structure, and paraformaldehyde by heating at a solid content concentration higher than that of the solution method, and have thus completed the present invention. That is, one aspect of the present invention includes the following configuration.

[0011] <1> A method for producing a benzoxazine compound, comprising a reaction step of heating a mixture of (A) phenol, (B) an amine composition containing a diamine represented by the following general formula (1) and an optional monoamine, and (C) paraformaldehyde to react with each other, wherein the solid content of the mixture is 80 to 100% by weight.

[0012] [ka]

[0013] In formula (1), R1 is represented by the following general formula (2).

[0014] [ka]

[0015] In formula (2), L1 and L3 are O (ether bond), L2 is any one of O (ether bond), C=O, SO2, C(CH3)2, C(CF3)2, or CH2, and p, q, r, s, and t are 0 or 1, provided that p+q+r+s+t≧1, and when s=0, p or q is 0, and when t=0, q or r is 0.

[0016] <2> In the above reaction step, the heating temperature is 90° C. or higher. <1> A method for producing the benzoxazine compound according to claim 1.

[0017] <3> In the reaction step, the heating time is 5 hours or less. <1> or <2> A method for producing the benzoxazine compound according to claim 1.

[0018] <4> The mixture contains (D) a solvent having a boiling point of 100° C. or higher in an amount of more than 0% by weight and less than 20% by weight. <1> ~ <3> 13. A method for producing a benzoxazine compound according to claim 12,

[0019] <5> The solvent (D) is at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), 1,4-dioxane, toluene, n-butyl acetate, and diethyl carbonate; <4> A method for producing the benzoxazine compound according to claim 1.

[0020] <6> When the solid content concentration of the product is less than 100% by weight at the time when the reaction step is completed, the method further includes a purification step of washing the reaction product. <1> ~ <5> 13. A method for producing a benzoxazine compound according to claim 12,

[0021] <7> The melting point of the diamine is 60° C. or higher. <1> ~ <6> 13. The method for producing a benzoxazine compound according to claim 12,

[0022] <8> The diamine is at least one selected from the compounds of the following formulas (3) to (16): <1> ~ <6> 13. The method for producing a benzoxazine compound according to claim 12,

[0023] [ka] TIFF0007654443000004.tif42164

[0024] <9> A method for producing a benzoxazine compound, comprising a reaction step of heating and reacting a mixture of (A1) a monophenolic composition containing phenol, (B1) an amine composition containing a diamine and an optional monoamine, and (C) paraformaldehyde, or a mixture of (A2) a phenolic composition containing bisphenol, (B2) a monoamine composition containing aniline, and (C) paraformaldehyde, wherein the solids concentration of the mixture is 80 to 100% by weight. Effect of the Invention

[0025] According to one aspect of the present invention, a new method for producing a benzoxazine-based compound can be provided, which can shorten the reaction time, improve the product yield, and reduce the environmental load compared to conventional methods. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] 1. Method for producing benzoxazine compounds A method for producing a benzoxazine compound according to one embodiment of the present invention (hereinafter also referred to as the present production method) includes a reaction step of heating a mixture of (A) phenol, (B) an amine composition containing a diamine represented by the following general formula (1) and a monoamine as an optional component, and (C) paraformaldehyde to react with each other, the solid content concentration of the mixture being 80 to 100% by weight. Here, the amine composition (B) contains 30 to 100% by weight of the diamine represented by the following general formula (1) and 70 to 0% by weight of the monoamine, preferably 50 to 100% by weight of the diamine represented by the following general formula (1) and 50 to 0% by weight of the monoamine, more preferably 70 to 100% by weight of the diamine represented by the following general formula (1) and 30 to 0% by weight of the monoamine.

[0027] [ka]

[0028] In formula (1), R1 is represented by the following general formula (2).

[0029] [ka]

[0030] In formula (2), L1 and L3 are O, L2 is any one of O, C=O, SO2, C(CH3)2, C(CF3)2, and CH2, and p, q, r, s, and t are 0 or 1, provided that p+q+r+s+t≧1, and when s=0, p or q is 0, and when t=0, q or r is 0.

[0031] As described above, the present inventors have succeeded in shortening the reaction time and increasing the yield of the obtained benzoxazine-based compound by reducing the amount of solvent used and setting the solid content (SC) of the raw material to 80 to 100% by weight, which is higher than that of the conventional solution method, when producing a benzoxazine-based compound. This also makes it possible to reduce the amount of by-products or unreacted materials, resulting in an increase in the consumption of paraformaldehyde. It is surprising that a technology for producing a benzoxazine-based compound based on such an idea has not existed before.

[0032] In this specification, "low environmental load" can be evaluated based on the proportion of paraformaldehyde remaining at the end of the reaction process. The less paraformaldehyde remaining at the end of the reaction process, the lower the environmental load can be evaluated. In addition, "low environmental load" also means that a smaller amount of solvent is required when producing a benzoxazine compound.

[0033] <1-1. Reaction process> This production method includes a reaction step of heating a mixture of (A) phenol, (B) an amine composition containing a diamine represented by the above general formula (1), and (C) paraformaldehyde to cause the mixture to react with each other.

[0034] The reaction step is carried out, for example, by mixing the raw materials, ie, (A) phenol, (B) the amine composition, and (C) paraformaldehyde, to obtain a mixture, which is then placed in a three-neck flask or the like and heated.

[0035] In the above reaction step, when the (B) amine composition is composed of only diamine, the molar ratio of (A) phenol:the above diamine:(C) paraformaldehyde is preferably 2:1:4 to 2:1:6. If the molar ratio is within the above range, the product yield is excellent. Here, when the (B) amine composition contains a monoamine, 2 moles of monoamine are converted to 1 mole of diamine, and the molar ratio can be calculated by adding up the number of moles of the diamine and the monoamine. In addition, the order of addition of the amine composition may be such that the diamine and the monoamine are simultaneously added and reacted, or the monoamine is added first and the diamine is added after a partial reaction. When the monoamine is added first, the generation of gel due to the reaction between the diamine and paraformaldehyde can be suppressed.

[0036] In the reaction step, the heating temperature is preferably 90° C. or higher, more preferably 100° C. or higher, even more preferably 120° C. or higher, and most preferably 130° C. or higher. If the temperature during the heating reaction is 80° C. or higher, it can exceed the melting point of the diamine used in the present production method, making it possible to melt the diamine, thereby improving the efficiency of the reaction step. The upper limit of the temperature during the heating reaction is not particularly limited, but may be, for example, 250° C. or lower.

[0037] In the reaction step, the heating time is preferably 5 hours or less, more preferably 4 hours or less, even more preferably 3 hours or less, and most preferably 2 hours or less. If the time for carrying out the reaction step is within the above range, the time is shorter than that of the conventional production method, and the production efficiency of the benzoxazine compound is improved. The lower limit of the heating time is not particularly limited as long as the raw material can be sufficiently heated and reacted, but may be, for example, 20 minutes or more.

[0038] The method for determining the heating time in the reaction step is not particularly limited, but can be determined, for example, based on the consumption of the raw material (A) phenol. When the heating time is determined based on the consumption of (A) phenol, the heating time may be the time when (A) phenol is expected to be consumed by 90% or more. The consumption of (A) phenol can be measured by 1H-NMR.

[0039] In the reaction step, the mixture is preferably stirred while being heated. Stirring can be performed, for example, by using a stirring blade, a magnetic stirrer, or a shaker, but is not limited thereto.

[0040] The mixture may be preheated before carrying out the reaction step. By preheating, (A) phenol and (B) the amine composition containing the diamine are easily dispersed. The preheating temperature is not particularly limited, but may be, for example, about 30 to 70°C.

[0041] In the reaction step of the present production method, the SC is more than 80% by weight and less than 100% by weight, more preferably 85-99% by weight, and most preferably 90-98% by weight. In this specification, the "solid content concentration (SC)" refers to the proportion of solid matter in the mixture in the present production method, assuming that (B) the amine composition containing the diamine, (A) phenol, and (C) paraformaldehyde are all solid. In the reaction step of the present production method, if the SC is 80% by weight or more, the raw materials are highly concentrated, so that the time required for the reaction is shortened and the yield of the obtained benzoxazine compound is improved. In the reaction step of the present production method, the SC can be adjusted, for example, by adding a solvent to the mixture.

[0042] In the reaction step of the present production method, the mixture preferably contains a solvent (D) having a boiling point of 100°C or higher in an amount of more than 0% by weight and less than 20% by weight. The amount of the solvent (D) used is more preferably 1 to 15% by weight, and even more preferably 2 to 10% by weight. If the amount of the solvent (D) used is less than 20% by weight, the raw materials become highly concentrated, so the time required for the reaction is shortened, and the yield of the obtained benzoxazine-based compound is improved. In addition, if the amount of the solvent (D) used is more than 0% by weight, there are the following advantages. For example, it is possible to use raw materials that do not melt at the reaction temperature of a normal melting method (a production method without using a solvent), that is, raw materials with a high melting point. In addition, although each raw material melts in the melting method, when combined, it becomes a heterogeneous phase, so that there may be raw materials that do not react easily. If the amount of the solvent used is more than 0% by weight, such a combination of raw materials can also be used.

[0043] The boiling point of the solvent (D) is preferably 100° C. or higher, more preferably 110° C. or higher, and even more preferably 120° C. or higher. When the boiling point of the solvent (D) is within the above range, the solvent (D) in the reaction product does not evaporate during the heating reaction, and the solvent (D) continues to exist in the reaction product, resulting in excellent reaction stability.

[0044] The above-mentioned solvent (D) may be either an organic solvent or an aqueous solvent, but from the viewpoint of the boiling point mentioned above, it is preferable that it is an organic solvent.

[0045] The solvent (D) may be, for example, one or more selected from the group consisting of N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), 1,4-dioxane, toluene, n-butyl acetate, and diethyl carbonate. Among these, the solvent (D) is preferably NMP in view of high solubility of the raw materials.

[0046] (Diamine) The amine composition (B) used in the present production method contains a diamine represented by the following general formula (1).

[0047] [ka]

[0048] In formula (1), R1 is represented by the following general formula (2).

[0049] [ka]

[0050] In formula (2), L1 and L3 are O, L2 is any one of O, C=O, SO2, C(CH3)2, C(CF3)2, and CH2, and p, q, r, s, and t are 0 or 1, provided that p+q+r+s+t≧1, and when s=0, p or q is 0, and when t=0, q or r is 0.

[0051] The diamine may have an amino group in the para, ortho, or meta position relative to R1. Each amino group may have the same or different coordinates relative to R1. That is, for example, both amino groups may be in the para position relative to R1, or one amino group may be in the meta position and the other amino group in the para position. Among these, it is preferable that both amino groups are in the para position relative to R1, both amino groups are in the meta position relative to R1, or one amino group is in the meta position and the other amino group is in the para position. It is more preferable that both amino groups are in the para position relative to R1, or one amino group is in the meta position and the other amino group is in the para position. Furthermore, it is most preferable that both amino groups are in the para position relative to R1.

[0052] In the above formula (2), the positions of L1, L2, and L3 are not particularly limited. That is, similarly to the case of formula (1), L1 and L3 may be in the para position, ortho position, or meta position relative to L2.

[0053] In the above formula (2), p to t are 0 or 1. Among the above p to t, the portion with a value of 0 is a single bond between carbons. That is, for example, when q is 0, the carbons of the benzene rings on both sides of L2 are single bonded to each other. In this case, the coordination is not particularly limited. That is, the benzene ring to which L3 is bonded may be in any of the para position, the ortho position, and the meta position with respect to L1. Also, in the above formula (2), p+q+r+s+t≧1. That is, all of p to t are not 0. That is, the benzene rings in the above formula (1) are not directly bonded to each other.

[0054] In the above formula (2), when s = 0, p or q is 0. When t = 0, q or r is 0. That is, L1 (ether bond) and L2 are not consecutive, and L2 and L3 (ether bond) are not consecutive.

[0055] The diamine has a melting point of preferably 60° C. or higher, more preferably 80° C. or higher, and even more preferably 100° C. or higher. If the diamine has a melting point within the above range, the diamine has excellent reactivity, and therefore the production efficiency of the benzoxazine compound is improved. The upper limit of the melting point of the diamine is not particularly limited, but may be 250° C. or lower in practice.

[0056] Specifically, the diamine may be one or more selected from the following compounds:

[0057] 1,3-Bis(4-aminophenoxy)benzene [RODA] (formula (3) below, melting point: 115.0 to 119.0°C)

[0058] [ka]

[0059] 3,4'-Diaminodiphenyl ether [3,4'-ODA] (formula (4) below, melting point: 67 to 71°C)

[0060] [ka]

[0061] 3,3'-Methylenedianiline [3,3'-MDA] (formula (5) below, melting point: 82.0 to 85.0°C)

[0062] [ka]

[0063] 4,4'-Methylenedianiline [4,4'-MDA] (formula (6) below, melting point: 91.0 to 94.0°C)

[0064] [ka]

[0065] 1,3-Bis(3-aminophenoxy)benzene [TPE-M] (formula (7) below, melting point: 107.0 to 109.0°C)

[0066] [ka]

[0067] 2,2-Bis[4-(4-aminophenoxy)phenyl]propane [BAPP] (formula (8) below, melting point: 128.0 to 131.0°C)

[0068] [ka]

[0069] 4,4'-Diaminodiphenyl ether [4,4'-ODA] (formula (9) below, melting point: 190.0 to 194.0°C)

[0070] [ka]

[0071] 4,4'-Bis(4-aminophenoxy)biphenyl [BAPB] (formula (10) below, melting point: 196.0 to 200.0°C)

[0072] [ka]

[0073] 4,4'-bis(3-aminophenoxy)biphenyl [3,3'-BAPB] (formula (11) below)

[0074] [ka]

[0075] 3,3'-Diaminobenzophenone [3,3'-DABP] (formula (12) below, melting point: 149.0 to 156.0°C)

[0076] [ka]

[0077] 4,4'-Diaminobenzophenone [4,4'-DABP] (formula (13) below, melting point: 245.0 to 249.0°C)

[0078] [ka]

[0079] 3,3'-Sulfonyldianiline [3,3'-DDS] (formula (14) below, melting point: 170 to 173°C)

[0080] [ka]

[0081] 4,4'-Sulfonyldianiline [4,4'-DDS] (formula (15) below, melting point: 175 to 177°C)

[0082] [ka]

[0083] Bis[4-(4-aminophenoxy)phenyl]sulfone [BAPS] (formula (16) below)

[0084] [ka]

[0085] Among the above-mentioned compounds, it is preferable that the diamine is 1,3-bis(4-aminophenoxy)benzene [RODA] from the viewpoints of ease of handling due to the melting point of the raw material being between 100°C and 250°C, stability and reactivity of the obtained benzoxazine-based compound, and heat resistance and mechanical properties of the cured product obtained therefrom.

[0086] (Monoamine) In the present production method, when a monoamine is used, for example, aromatic monoamines such as aniline, toluidines, xylidines, ethylanilines, ethynylanilines, chloroanilines, bromoanilines, nitroanilines, aminophenols, aminocresols, aminobenzyl alcohols, anisidines, phenetidines, aminobenzaldehydes, aminobenzonitriles, aminobiphenyls, aminophenyl phenyl ethers, aminobenzophenones, aminophenyl phenyl sulfides, aminophenyl phenyl sulfones, naphthylamines, amino-naphthols, and aminoanthracenes can be used. There is no particular limitation on the melting point, etc.

[0087] Among these, aniline or ethynylanilines are preferred from the viewpoints of handling, stability and reactivity of the resulting benzoxazine-based compound, heat resistance and mechanical properties of the cured product obtained therefrom, etc. When the monoamine is an ethynylaniline, it is expected that the thermal properties of the cured product will be further improved by thermal crosslinking of the ethynyl moiety.

[0088] (others) In this production method, (A) phenol is a monophenol having only one hydroxy group bonded to the benzene ring.

[0089] Also, (C) paraformaldehyde can be represented by the following general formula (17).

[0090] [ka]

[0091] <1-2. Purification process> The present production method may further include a purification step of washing the product when the SC of the product is less than 100% by weight at the time when the reaction step is completed. The purification step is carried out to remove the solvent contained in the product.

[0092] In the purification step, the liquid for washing the product is not particularly limited, but may be, for example, water, an alkaline solution, and / or an acidic solution. The alkaline solution is not particularly limited, but may be, for example, an aqueous NaOH solution. The acidic solution is not particularly limited, but may be, for example, an aqueous HCl solution. Any solution may be used for washing, and the order of washing is not particularly limited. That is, for example, washing with an alkaline solution may be followed by washing with water, or washing with water may be followed by washing with an alkaline solution. Also, washing with an alkaline solution may be followed by washing with an acidic solution. Among these, washing with an alkaline solution or washing with water is preferred, and a combination of washing with an alkaline solution and washing with water is more preferred.

[0093] Before carrying out the purification step, the product obtained in the reaction step may be diluted with a solvent such as chloroform. The solvent used for dilution can be removed by distillation under reduced pressure after the purification step is completed.

[0094] <1-3.Other> The present production method may be a method for producing a benzoxazine compound, comprising a reaction step of heating and reacting a mixture of (A1) a monophenol-based composition containing phenol, (B1) an amine-based composition containing a diamine and an optional monoamine, and (C) paraformaldehyde, or a mixture of (A2) a phenol-based composition containing bisphenol, (B2) a monoamine-based composition containing aniline, and (C) paraformaldehyde, wherein the SC of the mixture is 80 to 100% by weight.

[0095] In the reaction step of the present production method, the SC is more preferably more than 80% by weight and less than 100% by weight, further preferably 85 to 99% by weight, and most preferably 90 to 98% by weight.

[0096] <1-3-1> The case where a mixture of (A1), (B1) and (C) is used will be described below.

[0097] In the reaction step of the present production method, when the SC is 100% by weight, the (A1) monophenol-based composition containing phenol preferably consists of phenol alone. When the SC is 80% by weight or more but less than 100% by weight, the (A1) monophenol-based composition containing phenol preferably contains 51-100% by weight of phenol and 49-0% by weight of monophenol other than phenol, preferably contains 70-100% by weight of phenol and 30-0% by weight of monophenol other than phenol, more preferably contains 80-100% by weight of phenol and 20-0% by weight of monophenol other than phenol, and most preferably contains 90-100% by weight of phenol and 10-0% by weight of monophenol other than phenol.

[0098] The monophenol other than phenol has one or more phenolic hydroxyl groups on the aromatic ring, such as cresols, 3-methoxyphenols, 4-ethoxyphenols, fluorophenols, fluorocresols, ethynylphenols, cyanophenols, hydroxybenzaldehydes, dimethylphenols, ethylphenols, hydroxybenzyl alcohols, hydroxybenzenethiols, chlorophenols, allylphenols, naphthols, nitronaphthols, and hydroxypyrene, and is not particularly restricted in melting point. Among these, ethynylphenols are preferred from the viewpoints of handling, stability and reactivity of the obtained benzoxazine-based compound, and heat resistance and mechanical properties of the cured product obtained therefrom. When the monophenol is ethynylphenol, it is expected that the thermal properties of the cured product can be further improved by thermal crosslinking of the ethynyl moiety.

[0099] The conditions for using the (A1) monophenol-based composition containing phenol and the (B1) amine-based composition containing a diamine and an optional monoamine, as well as the SC and heating conditions in the reaction step, are as described in [1. Method for producing benzoxazine-based compound].

[0100] <1-3-2> The use of a mixture of (A2), (B2) and (C) is described below.

[0101] In the present production method, when only bisphenol is used as the phenolic composition containing bisphenol (A2), the molar ratio of bisphenol:aniline and monoamine:paraformaldehyde is preferably 1:2:4 to 1:2:6. When the phenolic composition containing bisphenol (A2) contains a monophenol, 2 moles of monophenol are converted to 1 mole of bisphenol, and the molar ratio can be calculated by adding up the number of moles of monophenol and bisphenol.

[0102] (monophenol) (A2) The phenolic composition containing bisphenol contains 30 to 100% by weight of bisphenol and 70 to 0% by weight of monophenol, preferably contains 50 to 100% by weight of bisphenol and 50 to 0% by weight of monophenol, and more preferably contains 70 to 100% by weight of bisphenol and 30 to 0% by weight of monophenol.

[0103] In the present production method, when bisphenol is used, for example, 2,2-bis(4-hydroxyphenyl)propane (commonly known as bisphenol A), bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, 2,2-bis(4-hydroxy-1-methylphenyl)propane, 1,1-bis(4-hydroxy-t-butylphenyl)propane, 2,2-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)octane, 2,2-bis(4-hydroxy-1-methylphenyl)propane, 1,1-bis(4-hydroxy-t-butylphenyl)propane, 2,2-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)methane ... bis(hydroxyaryl)alkanes such as 2,2-bis(4-hydroxy-3-bromophenyl)propane, 2,2-bis(4-hydroxy-3,5-dimethylphenyl)propane, 2,2-bis(4-hydroxy-3-chlorophenyl)propane, 2,2-bis(4-hydroxy-3,5-dichlorophenyl)propane, and 2,2-bis(4-hydroxy-3,5-dibromophenyl)propane; bis(hydroxyaryl)alkanes such as 2,2-bis(4-hydroxyphenyl)phenylmethane and bis(4-hydroxyphenyl)naphthylmethane; bis(hydroxyaryl)cycloalkanes such as 1,1-bis(4-hydroxyphenyl)cyclopentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, and 1,1-bis(4-hydroxyphenyl)-3,5,5-trimethylcyclohexane; dihydroxyaryl ethers such as 4,4'-dihydroxyphenyl ether and 4,4'-dihydroxy-3,3'-dimethylphenyl ether; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; dihydroxydiaryl sulfoxides such as 4,4'-dihydroxydiphenyl sulfoxide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfoxide; dihydroxydiaryl sulfones such as 4,4'-dihydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfone; and dihydroxydiphenyls such as 4,4'-dihydroxydiphenyl.Among these, bisphenol A is preferred from the viewpoints of ease of handling due to the melting point of the raw material being between 100°C and 250°C, the stability and reactivity of the resulting benzoxazine-based compound, and the heat resistance and mechanical properties of the cured product obtained therefrom.

[0104] The monophenol has one or more phenolic hydroxyl groups on the aromatic ring, such as phenol, cresols, 3-methoxyphenols, 4-ethoxyphenols, fluorophenols, fluorocresols, ethynylphenols, cyanophenols, hydroxybenzaldehydes, dimethylphenols, ethylphenols, hydroxybenzyl alcohols, hydroxybenzenethiols, chlorophenols, allylphenols, naphthols, nitronaphthols, and hydroxypyrene, and is not particularly restricted in melting point. Among these, phenol or ethynylphenols are preferred from the viewpoints of handling, stability and reactivity of the obtained benzoxazine-based compound, and heat resistance and mechanical properties of the cured product obtained therefrom. In the case of ethynylphenol, it is expected that the thermal properties of the cured product can be further improved by thermal crosslinking of the ethynyl moiety.

[0105] (B2) The monoamine composition containing aniline contains 51 to 100% by weight of aniline and 49 to 0% by weight of a monoamine other than aniline, preferably contains 70 to 100% by weight of aniline and 30 to 0% by weight of a monoamine other than aniline, more preferably contains 80 to 100% by weight of aniline and 20 to 0% by weight of a monoamine other than aniline, and most preferably contains 90 to 100% by weight of aniline and 10 to 0% by weight of a monoamine other than aniline.

[0106] Examples of the monoamines other than aniline include aromatic monoamines such as toluidines, xylidines, ethylanilines, ethynylanilines, chloroanilines, bromoanilines, nitroanilines, aminophenols, aminocresols, aminobenzyl alcohols, anisidines, phenetidines, aminobenzaldehydes, aminobenzonitriles, aminobiphenyls, aminophenyl phenyl ethers, aminobenzophenones, aminophenyl phenyl sulfides, aminophenyl phenyl sulfones, naphthylamines, amino-naphthols, and aminoanthracenes, and there are no particular restrictions on the melting point. Among these, ethynylanilines are preferred from the viewpoints of handling, stability and reactivity of the obtained benzoxazine-based compound, heat resistance and mechanical properties of the cured product obtained therefrom, and the like. When the monoamine is ethynylanilines, it is expected that the thermal properties of the cured product can be further improved by thermal crosslinking of the ethynyl moiety.

[0107] [2. Benzoxazine Compounds] The benzoxazine compound produced by the present production method (hereinafter also referred to as the present benzoxazine compound) is a compound represented by the following formula (17).

[0108] [ka]

[0109] In the above formula (17), R1 is determined by the diamine used as the raw material. In other words, it can be said that R1 is represented by the above formula (2). For example, when 1,3-bis(4-aminophenoxy)benzene represented by formula (3) is used as the above diamine, a benzoxazine compound represented by the following general formula (18) is obtained.

[0110] [ka]

[0111] The glass transition temperature (Tg) of the present benzoxazine-based compound is preferably 110°C or higher, more preferably 120°C or higher, and even more preferably 130°C or higher. If the Tg of the present benzoxazine-based compound is 110°C or higher, the present benzoxazine-based compound can be said to have excellent heat resistance. There is no particular upper limit for Tg, but in reality it may be 300°C or lower. In this specification, the term "glass transition temperature (Tg)" refers to the temperature at which the cured product of the present benzoxazine-based compound, which is cured by heating, undergoes glass transition.

[0112] The curing temperature (Tc) of the present benzoxazine compound is preferably 270° C. or less, more preferably 260° C. or less, and even more preferably 250° C. or less. If the Tc of the present benzoxazine compound is 270° C. or less, it becomes easy to produce a cured product from the present benzoxazine compound. In this specification, the "curing temperature (Tc)" means the temperature at which the uncured present benzoxazine compound is cured by heating.

[0113] The 5% weight loss temperature (Td5) of the present benzoxazine-based compound is preferably 290°C or higher, more preferably 300°C or higher, and even more preferably 310°C or higher. If the present benzoxazine-based compound has a temperature of 290°C or higher, it can be said that the present benzoxazine-based compound has excellent heat resistance. In this specification, the "5% weight loss temperature (Td5)" refers to the temperature at which the present benzoxazine-based compound is thermally decomposed and loses weight by 5%, measured in an environment in which the uncured present benzoxazine-based compound is cured.

[0114] The present benzoxazine-based compound can be suitably used in electronic parts, laminates for printed wiring boards and printed wiring boards, semiconductor encapsulation materials, electronic materials such as semiconductor-mounted modules, automobiles or vehicles, aircraft parts, building materials, machine tools, etc. Among these, it can be used particularly in parts that require heat resistance.

[0115] Specifically, for example, when the benzoxazine compound is used as a molding material for the above-mentioned parts or as a semiconductor encapsulation material, the benzoxazine compound can be used as it is, or can be used with the addition of a filler, a release agent, a flame retardant, a colorant, a coupling agent, etc., as necessary. In addition, a prepreg for a laminate can be produced by adding a solvent or the like to the benzoxazine compound to make a varnish, impregnating a substrate such as a glass cloth with this, and heating and drying it. Furthermore, the prepreg can be heated and pressed together with a metal foil to produce a laminate for a printed wiring board, and a circuit can be formed on the laminate to produce a printed wiring board. The printed wiring board produced in this way has excellent heat resistance and mechanical properties, and is therefore suitable for use as a semiconductor mounting substrate, etc.

[0116] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. EXAMPLES

[0117] Examples and comparative examples are given below to illustrate the present invention, but are not intended to limit the present invention. First, the methods for measuring each physical property are as follows.

[0118] [Measurement method] (1. Glass transition temperature (Tg)) The powder-shaped uncured product was subjected to differential scanning calorimetry (DSC) using a differential scanning calorimeter DSC7000X (manufactured by Hitachi High-Tech). Specifically, the DSC curve was measured under conditions of a nitrogen gas flow (40 mL / min) and a heating rate of 10°C / min. The temperature at the intersection of the tangent at the inflection point of the obtained DSC curve and the baseline was taken as Tg. The value of the 2nd scan of the DSC was used as Tg.

[0119] (2.Curing temperature (Tc)) Tc was calculated in the same manner as Tg, except that the values ​​from the first scan were used for DSC.

[0120] (3. Thermal decomposition temperature (Td5)) The powdered uncured material was evaluated for 5% weight loss temperature (Td5) at a heating rate of 10°C / min by thermogravimetric analysis (TGA) using Hitachi High-Tech's TG / DTA6300. Note that the Td5 value was measured under a N2 gas flow using differential thermal analysis (TG-DTA).

[0121] Example 1 2.193g (0.0075mol) of 1,3-bis(4-aminophenoxy)benzene, 1.412g (0.015mol) of phenol, and 1.081g (0.036mol) of paraformaldehyde were placed in a three-neck flask, heated and stirred at 130℃, and reacted for 30 minutes. The heating time was determined based on the time calculated by 1H-NMR at which the consumption rate of the raw material phenol was approximately 93%. Since no solvent was used, the solid content (SC) was set to 100% by weight.

[0122] After the heating reaction, 80 ml of chloroform was added to dissolve the product. After that, the mixture was washed three times with 80 ml of 1N NaOH aqueous solution and three times with 80 ml of pure water, and the solvent in the chloroform layer was distilled off under reduced pressure at 40°C. After that, the mixture was vacuum dried at 60°C for 6 hours to obtain a powder of the benzoxazine compound of the above formula (18).

[0123] The molecular weight of the obtained benzoxazine compound powder was measured by GPC, and the number average molecular weight (Mn) was 930 and the weight average molecular weight (Mw) was 1,752, calculated in terms of standard polystyrene.

[0124] Example 2 2.193g (0.0075mol) of 1,3-bis(4-aminophenoxy)benzene, 1.412g (0.015mol) of phenol, 1.081g (0.036mol) of paraformaldehyde, and 0.247g of N-methylpyrrolidone were placed in a three-neck flask, heated and stirred at 130℃, and reacted for 60 minutes. The heating time was determined in the same manner as in Example 1. The solid content (SC) was calculated based on the assumption that all of the diamine, phenol, and aldehyde had become solid. SC was 95% by weight.

[0125] After the reaction, 30 ml of chloroform was added to dilute the product, and the product was washed five times with 30 ml of pure water. After that, the product was washed three times with 30 ml of 1N NaOH aqueous solution and three times with 30 ml of pure water, and the solvent in the chloroform layer was distilled off under reduced pressure at 40°C. After that, the product was vacuum dried at 60°C for 6 hours to obtain a powder of the benzoxazine compound of the above formula (18).

[0126] The molecular weight of the obtained benzoxazine compound powder was measured by GPC, and the number average molecular weight (Mn) was 859 and the weight average molecular weight (Mw) was 1947, calculated as standard polystyrene.

[0127] Example 3 2.193g (0.0075mol) of 1,3-bis(4-aminophenoxy)benzene, 1.412g (0.015mol) of phenol, 1.081g (0.036mol) of paraformaldehyde, and 1.172g of N-methylpyrrolidone were charged into a three-neck flask, heated and stirred at 130°C, and reacted for 120 minutes. The heating time was determined in the same manner as in Example 1. The solid content (SC) was calculated in the same manner as in Example 2. SC=80% by weight.

[0128] After the reaction, 30 ml of chloroform was added to dilute the product, and the product was washed five times with 30 ml of pure water. Then, the product was washed three times with 100 ml of 1N NaOH aqueous solution and three times with 100 ml of pure water. Next, the product was washed three times with 100 ml of 0.1N HCl aqueous solution, and then washed three times with 100 ml of pure water, and the solvent in the chloroform layer was distilled under reduced pressure at 40°C. Then, the product was vacuum dried at 60°C for 6 hours to obtain a powder of the benzoxazine compound of the above formula (18).

[0129] The molecular weight of the obtained benzoxazine compound powder was measured by GPC, and the number average molecular weight (Mn) was 1,325 and the weight average molecular weight (Mw) was 5,215, calculated in terms of standard polystyrene.

[0130] Comparative Example 1 2.195g (0.0075mol) of 1,3-bis(4-aminophenoxy)benzene, 1.413g (0.015mol) of phenol, 2.925g (0.036mol) of 37% formalin, and 1.285g of ethyl acetate were placed in a three-neck flask, and reacted for 25 hours while heating and stirring at 80°C. The heating time was determined in the same manner as in Example 1. The solid content (SC) was calculated in the same manner as in Example 2. SC was 60% by weight.

[0131] After the reaction, 80 ml of chloroform was added to dilute the product, which was then washed three times with 80 ml of 1N NaOH aqueous solution and three times with 40 ml of pure water, and the solvent was removed from the chloroform layer under reduced pressure at 40° C. The mixture was then vacuum-dried at 60° C. for 6 hours to obtain a powder of the benzoxazine compound of the above formula (18).

[0132] The molecular weight of the obtained benzoxazine compound powder was measured by GPC, and the number average molecular weight (Mn) was 980 and the weight average molecular weight (Mw) was 2029, calculated as standard polystyrene.

[0133] 〔result〕 Table 1 shows the heating conditions during the reaction in Examples 1 to 3 and Comparative Example 1, and the results of evaluating the thermal properties of the resulting powder of the benzoxazine compound of formula (18) by DSC and TGA.

[0134] [Table 1]

[0135] From Table 1, it was found that the heating times of Examples 1 to 3 in which the SC was 80 to 100% by weight were much shorter than the heating time of Comparative Example 1 in which the SC was 60% by weight. It was also found that the benzoxazines of Examples 1 to 3 had equivalent performance in Tg, Tc, and Td5 to the benzoxazine of Comparative Example 1 obtained by the conventional solution method. Therefore, it was shown that the present production method can produce benzoxazine-based compounds in a shorter time than the conventional production method. [Industrial Applicability]

[0136] The present invention can be suitably used as a method for producing a benzoxazine compound.

Claims

1. A method for producing a phenol-based composition comprising: (A) a phenol; (B) an amine-based composition comprising a diamine represented by the following general formula (1) and an optional monoamine; and (C) paraformaldehyde; wherein the mixture has a solid content of 80% by weight or more and less than 100% by weight, The method for producing a benzoxazine compound, wherein the mixture contains more than 0 wt % of (D) a solvent having a boiling point of 100° C. or higher. 【Chemistry 1】 In formula (1), R1 is represented by the following general formula (2). 【Chemistry 2】 In formula (2), L1 and L3 are O (ether bond), L2 is O (ether bond), C═O, SO ２ , C(CH ３ ) ２ , C(CF ３ ) ２ , or C.H. ２ and p, q, r, s, and t are 0 or 1. However, p+q+r+s+t≧1, and when s=0, p or q is 0, and when t=0, q or r is 0.

2. The method for producing a benzoxazine compound according to claim 1, wherein the heating temperature in the reaction step is 90° C. or higher.

3. The method for producing a benzoxazine compound according to claim 1 or 2, wherein in the reaction step, the heating time is 5 hours or less.

4. A method for producing a phenol-based composition comprising: (A) phenol; (B) an amine-based composition comprising a diamine represented by the following general formula (1) and an optional monoamine; and (C) paraformaldehyde, the method comprising heating and reacting the mixture; wherein the solid content of the mixture is more than 80% by weight and less than 100% by weight, The mixture contains (D) a solvent having a boiling point of 100° C. or higher in an amount of more than 0% by weight and less than 20% by weight. 【Chemistry 3】 In formula (1), R1 is represented by the following general formula (2). 【Chemistry 4】 In formula (2), L1 and L3 are O (ether bond), L2 is any one of O (ether bond), C=O, SO2, C(CH3)2, C(CF3)2, or CH2, and p, q, r, s, and t are 0 or 1, provided that p+q+r+s+t≧1, and when s=0, p or q is 0, and when t=0, q or r is 0.

5. The method for producing a benzoxazine compound according to claim 4, wherein the solvent (D) is at least one selected from the group consisting of N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), 1,4-dioxane, toluene, n-butyl acetate, and diethyl carbonate.

6. The method for producing a benzoxazine compound according to any one of claims 1 to 5, further comprising a purification step of washing the product when the solid content concentration of the product is less than 100% by weight at the time when the reaction step is completed.

7. The method for producing a benzoxazine compound according to any one of claims 1 to 6, wherein the diamine has a melting point of 60°C or higher.

8. The method for producing a benzoxazine compound according to any one of claims 1 to 7, wherein the diamine is one or more selected from the compounds represented by the following formulas (3) to (16): 【Chemistry 5】 【change】

9. The method includes a reaction step of heating and reacting a mixture of (A1) a monophenol-based composition containing phenol, (B1) an amine-based composition containing a diamine and an optional monoamine, and (C) paraformaldehyde, or a mixture of (A2) a phenol-based composition containing bisphenol, (B2) a monoamine-based composition containing aniline, and (C) paraformaldehyde, wherein the solid content of the mixture is 80% by weight or more and less than 100% by weight, The method for producing a benzoxazine compound, wherein the mixture contains more than 0 wt % of (D) a solvent having a boiling point of 100° C. or higher.

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