Resin composition and cured product thereof

Abstract

Provided is a resin composition containing benzoxazine having a terminal unsaturated hydrocarbon group, which has an improved glass transition temperature of the cured product. The resin composition according to the present invention contains a compound represented by formula (1) and a specific polycitraconimide compound having multiple citraconic acid groups in one molecule. 1 represents a divalent hydrocarbon group which may contain a heteroatom, and R 2 and R 3 represents an alkanediyl group having 1 to 10 carbon atoms, and R 4 and R 5 represents a hydrogen atom or a methyl group, and R 6 and R 7 represents a methyl group or an ethyl group, and p and q represent integers of 0 to 2. JPEG0007727873000022.jpg33150

Description

[Technical Field]

[0001] An embodiment of the present invention relates to a resin composition containing benzoxazine and a cured product thereof. [Background technology]

[0002] Benzoxazine is a compound having a benzoxazine ring formed by a condensation reaction of a phenol, an amine, and formaldehyde. Benzoxazine is a thermosetting monomer that hardens when heated by ring-opening polymerization of the benzoxazine ring.

[0003] For example, Patent Document 1 discloses a benzoxazine having two benzoxazine rings per molecule, which is obtained by a condensation reaction between phenol, 4,4'-diaminodiphenylmethane, and paraformaldehyde. Patent Document 2 discloses a benzoxazine having benzoxazine rings at the 3- and 4'-positions of the diphenyl ether group, which is obtained by a condensation reaction between phenol, 3,4'-diaminodiphenyl ether, and formaldehyde.

[0004] On the other hand, it is known that biscitraconimide is used as a material for printed circuit boards, for example. Biscitraconimide does not cure by itself, but it is known that it can be cured by adding a crosslinking agent (curing agent).

[0005] For example, Patent Document 3 describes that benzoxazine may be added as a curing agent to a resin material containing a maleimide compound having a skeleton derived from dimer diamine, and that the maleimide compound may be a citraconic imide compound. Patent Document 4 describes that benzoxazine may be added as a crosslinking agent to a film-forming material for lithography containing a polycitraconimide compound. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 4647398 [Patent Document 2] Japanese Patent Application Publication No. 2018-184533 [Patent Document 3] International Publication No. 2020 / 045408 [Patent Document 4] International Publication No. 2020 / 004316 Summary of the Invention [Problem to be solved by the invention]

[0007] Some benzoxazines have an allyl group at the molecular terminal. Such terminal unsaturated hydrocarbon groups do not react with the thermal ring-opening polymerization of benzoxazine, but can react with other polymerizable monomers. When such benzoxazines with terminal unsaturated hydrocarbon groups are used, for example, as materials for printed circuit boards, the glass transition temperature of the cured product must be high.

[0008] An object of an embodiment of the present invention is to improve the glass transition temperature of a cured product of a resin composition containing a benzoxazine having a terminal unsaturated hydrocarbon group. [Means for solving the problem]

[0009] The present invention includes the embodiments shown below. [1] A compound represented by the following general formula (1) and a citraconic acid imide represented by the following general formula (2), [ka] In formula (1), R 1 represents a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a heteroatom, and R 2 and R 3 each independently represents an alkanediyl group having 1 to 10 carbon atoms, and R 4 and R 5 each independently represents a hydrogen atom or a methyl group, R 6 and R 7each independently represents a methyl group or an ethyl group, and p and q each independently represent an integer of 0 to 2; [ka] In formula (2), R 8 each independently represents an alkyl group having 1 to 3 carbon atoms, each m independently represents an integer of 0 to 3, and n is the average number of repeating units and is a number greater than 0. Resin composition.

[0010] [2] R in the formula (1) 1 The resin composition according to [1], wherein is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms which may contain a heteroatom.

[0011] [3] The compound represented by formula (1) is represented by the following general formula (1A): [ka] In formula (1A), R 11 represents a single bond, -CH2-, -CH(CH3)-, -C(CH3)2-, or -O-; R 12 and R 13 each independently represents a methyl group or an ethyl group, s and t each independently represent an integer of 0 to 4, R 2 and R 3 each independently represents an alkanediyl group having 1 to 10 carbon atoms, and R 4 and R 5 each independently represents a hydrogen atom or a methyl group, R 6 and R 7 each independently represents a methyl group or an ethyl group, and p and q each independently represent an integer of 0 to 2. The resin composition according to [1] or [2].

[0012] [4] The resin composition according to any one of [1] to [3], wherein n in the formula (2) is 0.10 to 15.0.

[0013] [5] The resin composition according to any one of [1] to [4], which is used as a printed circuit board material.

[0014] [6] A cured product obtained by curing the resin composition according to any one of [1] to [5].

[0015] [7] Use of the resin composition according to any one of [1] to [4] as a printed circuit board material. [Effects of the Invention]

[0016] According to an embodiment of the present invention, the glass transition temperature of a cured product of a resin composition containing a benzoxazine having a terminal unsaturated hydrocarbon group can be improved. DETAILED DESCRIPTION OF THE INVENTION

[0017] The resin composition according to this embodiment contains a compound represented by the following general formula (1) (hereinafter referred to as compound (1)): Compound (1) is a compound composed of one molecule of diamine, two molecules of a phenol, and four molecules of formaldehyde, and has two benzoxazine rings in the molecule. [ka]

[0018] In formula (1), R 1 R represents a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a heteroatom. 1 The number of carbon atoms in the hydrocarbon group is preferably 2 to 70, more preferably 3 to 50, more preferably 5 to 30, and even more preferably 6 to 20. Examples of heteroatoms include oxygen atoms, nitrogen atoms, sulfur atoms, fluorine atoms, and silicon atoms, and an oxygen atom is preferred. 1 Preferably, does not contain heteroatoms.

[0019] R 1The hydrocarbon group preferably contains an aromatic ring (i.e., is an aromatic ring-containing hydrocarbon group), more preferably contains a benzene ring, and even more preferably contains two or three benzene rings. 1 The hydrocarbon group preferably has 6 to 50 carbon atoms, more preferably 12 to 30 carbon atoms, and even more preferably 12 to 20 carbon atoms.

[0020] In formula (1), R 2 and R 3 each independently represents an alkanediyl group (also called an alkylene group) having 1 to 10 carbon atoms. The alkanediyl group may be linear or branched. Preferably, R 2 and R 3 are each independently an alkanediyl group having 1 to 5 carbon atoms, more preferably an alkanediyl group having 1 to 3 carbon atoms, more preferably an ethylene group (-CH2CH2-) or a methylene group (-CH2-), and even more preferably a methylene group.

[0021] In formula (1), R 4 and R 5 each independently represents a hydrogen atom or a methyl group, and more preferably a hydrogen atom. 4 R 2 - and H2C=CR 5 R 3 The unsaturated hydrocarbon group represented by - is CR so that it has an allyl group (H2C=CH-CH2-) or a methallyl group (H2C=C(CH3)-CH2-) at its terminal. 4 or CR 5 Preferably, the carbon adjacent to is a methylene group.

[0022] In formula (1), R 6 and R 7 each independently represents a methyl group or an ethyl group, more preferably a methyl group. In formula (1), p and q each independently represent an integer of 0 to 2, more preferably each independently represents 0 or 1, and even more preferably 0.

[0023] In formula (1), H2C=CR 4 R 2 - and H2C=CR 5 R 3 - and an unsaturated hydrocarbon group represented by R 6 and R 7 For the substituents represented by the formula (I), their bonding positions relative to the benzene ring are preferably set as follows: One unsaturated hydrocarbon group and 0 to 2 of the substituents are bonded to the benzene ring, provided that at least one of the ortho- and para-positions relative to the oxygen atom bonded to the benzene ring is unsubstituted (i.e., a hydrogen atom). Preferably, the unsaturated hydrocarbon group is bonded to the ortho-position relative to the oxygen atom.

[0024] Compound (1) is more preferably represented by the following general formula (1A). [ka]

[0025] In formula (1A), R 11 represents a single bond, -CH2-, -CH(CH3)-, -C(CH3)2-, or -O-. 11 is preferably a single bond, -CH2-, or -O-, more preferably a single bond or -CH2-. 11 The bonding position of Ph-R 11 -Ph (wherein Ph is a substituent R 12 or R 13 The bonding positions of the benzoxazine ring to the benzene ring are preferably the 4,4'-positions, the 3,4'-positions, or the 3,3'-positions.

[0026] In formula (1A), R 12 and R 13 R each independently represents a methyl group or an ethyl group, and is more preferably a methyl group. 12 and R 13When a plurality of s and t are present in one molecule, they may be the same or different. s and t each independently represent an integer of 0 to 4, more preferably an integer of 0 to 2, and even more preferably 0 or 1.

[0027] In formula (1A), R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , p and q are R in formula (1), 2 , R 3 , R 4 , R 5 , R 6 , R 7 , p and q.

[0028] In one embodiment, compound (1) is preferably represented by the following general formula (1B). [ka] In formula (1B), R 11 , R 12 , R 13 , R 2 , R 3 , R 4 , R 5 , s and t are R in formula (1A), respectively. 11 , R 12 , R 13 , R 2 , R 3 , R 4 , R 5 , s and t.

[0029] In one embodiment, compound (1) may be a compound represented by the following general formula (1C): [ka] In formula (1C), R 2 , R 3 , R 4 and R 5 are R in formula (1A), respectively. 2 , R 3, R 4 and R 5 is the same as:

[0030] In one embodiment, compound (1) may be a compound represented by the following general formula (1D). [ka] In formula (1D), R 12 , R 13 , R 2 , R 3 , R 4 and R 5 are R in formula (1A), respectively. 12 , R 13 , R 2 , R 3 , R 4 and R 5 is the same as:

[0031] The method for producing compound (1) is not particularly limited, and for example, compound (1) can be obtained by a condensation reaction of a phenol, a diamine, and formaldehyde. Specifically, in the presence of a solvent, a phenol represented by the following formula (3), a diamine represented by the following formula (4), and formaldehyde (e.g., paraformaldehyde, i.e., (HCHO) n ) and a method of stirring and mixing them and causing a dehydration condensation reaction under heating. After the condensation reaction, purification may be performed by separation washing, recrystallization, column purification, or the like. [ka]

[0032] In equation (3), R 14 is H2C=CR 4 R 2 - or H2C=CR 5 R 3 - where R 2 , R 3 , R 4 and R 5 are R in equation (1), respectively. 2 , R 3 , R 4 and R 5is the same as R 15 is R in the above formula (1). 6 or R 7 In formula (4), R is the same as p or q in formula (1). 1 is R in the above formula (1). 1 is the same as

[0033] Examples of the solvent include organic solvents capable of dissolving benzoxazine, such as toluene, xylene, cumene, monochlorobenzene, methyl ethyl ketone, ethyl acetate, butyl acetate, chloroform, dichloromethane, THF, dioxane, dimethylformamide, etc. These may be used alone or in combination of two or more.

[0034] Regarding the ratio of phenols, diamines, and formaldehyde, since the target compound represented by formula (1) can be obtained by reacting 2 moles of phenols with 4 moles of formaldehyde per mole of diamine, the amounts charged can be set based on this. For example, the amount of phenols charged per mole of diamine is preferably 2.0 to 2.5 moles, more preferably 2.0 to 2.2 moles, and even more preferably 2.0 to 2.1 moles. The amount of formaldehyde charged per mole of diamine is preferably 3.9 to 5.0 moles, more preferably 4.0 to 4.5 moles, and even more preferably 4.0 to 4.3 moles.

[0035] The reaction product obtained by the above-described condensation reaction typically contains, in addition to compound (1) as the main product, by-products such as a ring-opened product in which one of the two benzoxazine rings of compound (1) is not closed but is instead opened, and a polymer (including oligomer) of compound (1). The resin composition according to the embodiment may contain, as the benzoxazine, compound (1) as well as a by-product corresponding to compound (1). That is, compound (1) and a by-product (as an optional component) corresponding to compound (1) are collectively referred to as benzoxazine, and the resin composition according to the embodiment contains this benzoxazine. The proportion of compound (1) in the benzoxazine is not particularly limited, but is preferably 40% or more, more preferably 45% or more, and even more preferably 50% or more. The upper limit of the proportion of compound (1) is not particularly limited, but the proportion is typically 80% or less, and may be 70% or less. Here, the proportion of compound (1) is the peak area ratio measured by GPC.

[0036] The resin composition according to this embodiment contains citraconic imide (hereinafter referred to as citraconic imide (CI)) represented by the following general formula (2): Citraconimide (CI) has multiple citraconic imide groups in one molecule, and is therefore also called polycitraconimide. [ka]

[0037] In equation (2), R 8 each independently represents an alkyl group having 1 to 3 carbon atoms, preferably a methyl group or an ethyl group. m each independently represents an integer of 0 to 3, preferably 0 or 1, and more preferably 0.

[0038] In formula (2), n is the average number of repeating units and is a number greater than 0. That is, n is a repeating unit represented by -CH2-Ph(Ci)- (where Ph is a substituent R 8and Ci represents a benzene ring which may have one or more repeating units, and Ci represents a citraconic imide group. ) represents the average value of the number of repeating units, and n>0. By including a compound having one or more repeating units in this way, the solvent solubility can be improved.

[0039] From the viewpoints of solvent solubility and low water absorption, the average number of repeating units n is preferably 0.10 to 15.0, more preferably 0.10 to 10.0, more preferably 0.10 to 5.0, more preferably 0.10 to 2.0, even more preferably 0.10 to 1.5, and particularly preferably 0.10 to 1.0. The average number of repeating units n is a value calculated from the number average molecular weight Mn by GPC.

[0040] In formula (2), the bonding positions of the citraconic imide group and the methylene group to the benzene ring are not particularly limited, and may be the ortho, meta, or para positions, preferably the ortho or para positions.

[0041] The citraconic acid imide (CI) may be a mixture containing a plurality of compounds having different numbers of repeating units, and typically is such a mixture. In one embodiment, the citraconic acid imide (CI) preferably has a peak area ratio of 65% or less by GPC for compounds having zero repeating units. The citraconic acid imide (CI) may consist solely of compounds having one or more repeating units, or may contain compounds having zero repeating units and one or more compounds (e.g., compounds having 1 to 10, more preferably 1 to 6, and even more preferably 1 to 4 repeating units). For example, the citraconic acid imide (CI) may contain, in terms of peak area ratio by GPC, 5 to 65% (preferably 15 to 60%, more preferably 30 to 60%, and even more preferably 40 to 60%) of compounds having zero repeating units and 35 to 95% (preferably 40 to 85%, more preferably 40 to 70%, and even more preferably 40 to 60%) of compounds having one or more repeating units.

[0042] The number average molecular weight Mn of citraconic imide (CI) measured by GPC is not particularly limited, and may be, for example, 400 to 3000, 400 to 2000, 400 to 1500, 400 to 1000, 400 to 800, or 400 to 600.

[0043] There are no particular limitations on the method for producing citraconic imide (CI), and it can be obtained, for example, by subjecting a condensate of substituted or unsubstituted aniline and formaldehyde to a dehydration condensation reaction with citraconic anhydride.

[0044] The resin composition according to the embodiment is a thermosetting resin composition containing compound (1) and citraconic imide (CI). Specifically, compound (1) has a benzoxazine ring, and therefore cures (thermosets) as a monomer by thermal ring-opening polymerization. In addition, the H2C=CR of compound (1) 4 R 2 - and H2C=CR 5 R 3 The unsaturated hydrocarbon group represented by - reacts with the citraconic acid group of citraconic acid (CI), causing citraconic acid (CI) to thermally cure together with compound (1). Therefore, it is believed that the cured product of the resin composition according to the embodiment has a higher glass transition temperature than when compound (1) is cured alone. Furthermore, in the resin composition according to the embodiment, citraconic acid (CI) has higher solvent solubility than bismaleimide, a similar substance. Furthermore, the resin composition according to the embodiment has high reactivity in the curing reaction and excellent moldability of the cured product. Furthermore, the resin composition according to one embodiment has a low water absorption rate and excellent low water absorption properties.

[0045] In the resin composition according to the present embodiment, the compounding ratio of compound (1) to citraconic imide (CI) is not particularly limited, but may be set as follows in one embodiment. As described above, compound (1) is typically produced together with by-products such as ring-opened products and polymers. Therefore, it is preferable to set the compounding ratio of citraconic imide (CI) to a benzoxazine containing these by-products. That is, the mass ratio of benzoxazine (BZO) composed of compound (1) and its by-products to citraconic imide (CI), i.e., the mass ratio of BZO to CI, BZO / CI, is preferably 0.35 to 4.0, more preferably 0.4 to 3.0, and even more preferably 0.8 to 2.0. By setting BZO / CI to 4.0 or less, the glass transition temperature of the cured product can be improved. By setting BZO / CI to 0.35 or more, the moldability and low water absorption of the cured product can be improved.

[0046] The resin composition according to the embodiment may be composed solely of the benzoxazine (BZO) containing compound (1) and citraconic imide (CI), or may contain, in addition to BZO and CI, other thermosetting resins and / or thermoplastic resins. The resin composition may also contain various known additives such as solvents, catalysts, crosslinking agents, curing accelerators, colorants, radical polymerization initiators, leveling agents, flame retardants, antioxidants, and inorganic fillers.

[0047] In the resin composition, the total amount of benzoxazine (BZO) and citraconic imide (CI) is preferably 50% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, or may be 100% by mass, excluding the solvent. In one embodiment, the resin composition is a resin solution containing a solvent. In this case, the content of the solvent in the resin composition is not particularly limited and may be, for example, 30 to 70% by mass or 40 to 60% by mass.

[0048] Examples of solvents contained in the resin composition include organic solvents capable of dissolving benzoxazine (BZO) and citraconic imide (CI), such as toluene, xylene, cumene, monochlorobenzene, methyl ethyl ketone, ethyl acetate, butyl acetate, chloroform, dichloromethane, THF, dioxane, and dimethylformamide. These may be used alone or in combination of two or more. Aromatic hydrocarbon solvents and ketone solvents are preferred as solvents. Furthermore, from the viewpoint of removability when removing the solvent by evaporation or the like during curing, non-halogen solvents with a boiling point of 150°C or less are preferred.

[0049] Examples of catalysts contained in the resin composition include imidazole catalysts such as 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, and 1,2-dimethylimidazole, and organophosphorus catalysts such as triphenylphosphine and tributylphosphine.

[0050] The cured product according to this embodiment is obtained by curing the resin composition, and is usually cured by heating. The curing conditions are not particularly limited, and may be, for example, heating at 150°C to 250°C for 30 to 180 minutes. If the resin composition contains a solvent, the solvent may be evaporated by heating, and then the temperature may be further increased to perform thermal curing.

[0051] The resin composition according to this embodiment can be used for various purposes, such as an electrical insulating material or a matrix resin for composite materials.

[0052] In one embodiment, the resin composition is preferably used as a printed circuit board material. That is, the printed circuit board material according to one embodiment includes a resin composition containing compound (1) and citraconic imide (CI). The printed circuit board material can be used to produce a printed circuit board, such as a printed wiring board or a printed circuit board according to one embodiment.

[0053] Examples of printed circuit board materials include rigid printed circuit board materials for producing single-sided boards, double-sided boards, multilayer boards, build-up boards, etc., and flexible printed circuit board materials for producing film- or sheet-shaped flexible printed circuit boards. [Example]

[0054] The present invention will be explained in more detail below based on examples and comparative examples, but the present invention is not limited thereto.

[0055] <Measurement and evaluation methods> [Purity of the main product in benzoxazine] BZO1-4 obtained in Synthesis Examples 1-2 and Comparative Synthesis Examples 1-2 were dissolved in THF to a reaction product concentration of approximately 0.2 mg / mL. GPC analysis was performed using a gel permeation chromatography (GPC) system (Prominence, Shimadzu Corporation) connected to four columns packed with polystyrene gel (Shodex GPC columns KF-601, KF-602, KF-603, and KF-604, Resonac Corporation). The measurement conditions were a column oven temperature of 40°C, a flow rate of 0.6 mL / min, and a differential refractive index detector (Shodex RI-504, Resonac Corporation). After removing peaks derived from the solvent (toluene) from the resulting chromatogram, the purity of the main product was calculated as the peak area ratio (%).

[0056] [Composition analysis of citraconimide] GPC measurement was performed on CI1 and CI2 obtained in Synthesis Examples 3 and 5 in the same manner as for the purity of the main product in benzoxazine, and the peak area ratio of the compound having 0 repeating units was measured. The peak position of the compound having 0 repeating units was assigned by GPC measurement of 4,4'-biscitraconimidodiphenylmethane.

[0057] [Number average molecular weight Mn] For CI1 and CI2 obtained in Synthesis Examples 3 and 5 and MI1 obtained in Comparative Synthesis Example 3, GPC measurement was carried out in the same manner as for the purity of the main product in benzoxazine described above, and the number average molecular weight Mn in terms of polystyrene was measured.

[0058] [Solubility] The components were mixed according to the formulations (units are g) shown in Tables 1 and 2, and the mixture that dissolved uniformly at room temperature was classified as "A." The mixture that dissolved uniformly after heating to 50°C was classified as "B." The mixture that still contained insoluble material even after heating to 50°C was classified as "C."

[0059] [Moldability] For Examples and Comparative Examples that received an A or B solubility rating, a resin composition prepared according to the formulation (g) shown in Table 1 or Table 2 was placed in an aluminum cup with an upper diameter of 60 mm, a lower diameter of 54 mm, and a depth of 16 mm, and heated on a hot plate at 120°C for one hour to distill off the solvent. The hot plate was then heated to 250°C and heated for one hour to perform thermal curing, and the plate was allowed to cool to room temperature to produce a flat plate. Plates with noticeable appearance defects due to the occurrence of bubbles, cracks, and poor curing throughout were rated "B," while plates with minor or no visible appearance defects were rated "A."

[0060] [Glass transition temperature (Tg)] For Examples and Comparative Examples that received a solubility rating of A or B, a resin composition prepared according to the formulation (g) shown in Table 1 or Table 2 was placed in an aluminum cup with an upper diameter of 60 mm, a lower diameter of 54 mm, and a depth of 16 mm. The cup was heated on a hot plate at 120°C for 1 hour to remove the solvent. The hot plate was then heated to 250°C for 1 hour to perform thermal curing, and the resulting plate was then cooled to room temperature to produce a flat plate. For samples that received a moldability rating of A, test specimens measuring 5 mm wide, approximately 1 mm thick, and 30 mm long were prepared from the resulting flat plate. The glass transition temperature was then measured using a dynamic viscoelasticity measuring device: Rheogel-E4000 (manufactured by UBM Corporation). The glass transition temperature of the test specimen was determined as the temperature at which the loss tangent (tanδ) reached its maximum value under conditions of a tensile sine wave, a dynamic strain of 5 μm, a frequency of 1 Hz, and a temperature rise rate of 3°C / min.

[0061] [Water absorption rate] Test pieces similar to those used to measure the glass transition temperature in Examples 1 to 9 and Comparative Example 7 were prepared, and the mass increase (%) before and after immersion in water at 25°C for 24 hours was measured and calculated as the water absorption at 25°C. Similarly, the mass increase (%) before and after immersion in water at 40°C for 24 hours was measured and calculated as the water absorption at 40°C.

[0062] <Synthesis Example 1> A 5L reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 521.0 g of 4,4'-diaminodiphenylmethane, 705.2 g of 2-allylphenol, and 1569.3 g of toluene and dissolved at 75°C. Next, 343.1 g of 92% by weight paraformaldehyde was added in five portions, and the reaction solution was heated to distill off the water produced by the dehydration condensation reaction. The reaction solution was then heated to 105-110°C and the reaction continued for 6 hours. After cooling to room temperature, the reaction solution was diluted with 301.7 g of toluene. 784.6 g of 10% by weight aqueous sodium hydroxide was added, stirred for 15 minutes, allowed to stand, and the aqueous layer was separated and removed. This procedure was repeated twice. 627.7 g of water and 156.9 g of isopropyl alcohol (IPA) were then added to the resulting organic layer, stirred for 15 minutes, allowed to stand, and the aqueous layer was separated and removed. This procedure was repeated five times. The water and IPA in the resulting organic layer were removed under reduced pressure using a rotary evaporator to obtain a toluene solution (BZO1) containing the reaction product at a concentration of 49.8% by mass. The resulting reaction product was benzoxazine, containing the compound represented by the following formula as the main product, and the purity of the main product by GPC was 56.2%. [ka]

[0063] <Synthesis Example 2> A 5L reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 436.9 g of 4,4'-diamino-2,2'-dimethylbiphenyl, 552.0 g of 2-allylphenol, and 1257.6 g of toluene and dissolved at 75°C. Next, 268.7 g of 92% by weight paraformaldehyde was added in five portions, and the reaction solution was heated to distill off the water produced by the dehydration condensation reaction. The reaction solution was then heated to 105-110°C and the reaction continued for 6 hours. After cooling to room temperature, the reaction solution was diluted with 168.4 g of toluene. 503.0 g of 10% by weight aqueous sodium hydroxide solution and 125.8 g of IPA were added, stirred for 15 minutes, allowed to stand, and the aqueous layer was separated and removed. This procedure was repeated twice, and the resulting organic layer was diluted with 179.2 g of toluene. To this, 503.0 g of water and 125.8 g of IPA were added, stirred for 15 minutes, allowed to stand, and the aqueous layer was separated and removed. This operation was repeated five times. The water and IPA in the resulting organic layer were distilled off under reduced pressure to obtain a toluene solution (BZO2) containing the reaction product at a concentration of 51.4 mass%. The resulting reaction product was benzoxazine, containing the compound represented by the following formula as the main product, and the purity of the main product by GPC was 61.7%. [ka]

[0064] <Synthesis Example 3> A 3-L reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 200.4 g of citraconic anhydride and 1135.6 g of toluene and mixed. A solution of 160.0 g of polydiaminodiphenylmethane (WANAMINE MDA-60R, manufactured by WANHUA CHEMICAL GROUP CO., LTD.) dissolved in 480.0 g of N-methylpyrrolidone (NMP) was added dropwise and allowed to react for 30 minutes. After adding 15.5 g of paratoluenesulfonic acid monohydrate, the reaction mixture was heated and the water produced by the dehydration condensation reaction was distilled off from the system. The reaction was continued at 105-115°C for 4 hours, after which the reaction mixture was cooled. 480.0 g of water was added to the mixture, and the mixture was stirred at 55-65°C. The mixture was then allowed to stand and the aqueous layer was separated and removed. This procedure was repeated three times, and the resulting organic layer was concentrated using a rotary evaporator to obtain a toluene solution (CI1) containing the reaction product at a concentration of 67.8% by mass. The resulting reaction product was citraconic imide represented by the following formula, with an Mn of 410. The peak area ratio of the compound containing 0 repeating units measured by GPC was 58.5%. The average repeating unit number (n) calculated from the Mn was 0.12. [ka]

[0065] <Synthesis Example 4> A 300 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 47.3 g of aniline and 25.3 g of 35% by weight aqueous hydrochloric acid, and the temperature was raised to 60°C. 30.9 g of 37% by weight aqueous formaldehyde was added dropwise over 30 minutes, and the reaction was allowed to proceed at 80°C for 1 hour. The reaction solution was heated and the reaction was continued at 120°C while distilling water out of the system. After water no longer distilled, the reaction was continued for another 30 minutes. After cooling to 90°C, 30.7 g of 30% by weight aqueous sodium hydroxide was added dropwise to neutralize the mixture, and the system was allowed to cool to 50°C or below. 100.0 g of chloroform was added to dissolve the product, and 100.0 g of water was added, stirred, and allowed to stand, followed by separation and removal of the aqueous layer. This procedure was repeated three times. The resulting organic layer was concentrated using a rotary evaporator and further dried in vacuo at 80°C to obtain an aniline formaldehyde condensate having an amine value of 539.7 mg-KOH / g.

[0066] <Synthesis Example 5> A 300 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 23.7 g of citraconic anhydride, 134.3 g of toluene, and 30.0 g of N-methylpyrrolidone (NMP) and mixed. A solution of 20.0 g of the aniline-formaldehyde condensate synthesized in Synthesis Example 4 dissolved in 30.0 g of NMP was added dropwise and allowed to react for 30 minutes. After adding 1.8 g of paratoluenesulfonic acid monohydrate, the reaction mixture was heated and the water produced by the dehydration condensation reaction was distilled off from the system at 105–115°C for 4 hours. The reaction mixture was then cooled. The toluene in the reaction mixture was distilled off under reduced pressure and then diluted with 134.3 g of methyl ethyl ketone (MEK). 60.0 g of water was added, stirred, allowed to stand, and the aqueous layer was separated and removed. This cycle was repeated four times. The resulting organic layer was then concentrated using a rotary evaporator to obtain a solution with a concentration of approximately 60% by mass. This solution was poured into 762 g of methanol, and the precipitated solid was collected and dried under vacuum at 80°C to obtain a reaction product (CI2). The resulting reaction product was citraconic imide represented by the formula described in Synthesis Example 3, with an Mn of 650. The peak area ratio of the compound with 0 repeating units measured by GPC was 20.1%. The average number of repeating units, n, calculated from Mn was 1.3.

[0067] <Comparative Synthesis Example 1> 79.3 g of 4,4'-diaminodiphenylmethane, 75.3 g of phenol, and 206.8 g of toluene were added to a 500 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer and dissolved at 75 °C. Next, 52.2 g of 92% by weight paraformaldehyde was added in five portions. The reaction solution was heated to 105 °C over approximately 3 hours, and the water produced by the dehydration condensation reaction was distilled out of the system. The reaction solution was then cooled to room temperature. The reaction solution was poured into 1034 g of IPA, and the precipitated solid was collected and vacuum dried at 50 °C to obtain the reaction product (BZO3). The resulting reaction product was a benzoxazine containing the compound represented by the following formula as the main product. GPC analysis revealed that the purity of the main product was 44.1%. [ka]

[0068] <Comparative Synthesis Example 2> 21.2 g of 4,4'-diamino-2,2'-dimethylbiphenyl, 18.8 g of phenol, and 53.0 g of toluene were added to a 300 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer and dissolved at 75 °C. Next, 13.0 g of 92% by weight paraformaldehyde was added in five portions, and the reaction solution was heated to distill off the water produced by the dehydration condensation reaction. The reaction solution was then heated to 105-110 °C and the reaction continued for 4 hours, after which the reaction solution was cooled to room temperature. This reaction solution was poured into 530 g of methanol, and the precipitated solid was collected and dried in vacuo at 40 °C to obtain the reaction product (BZO4). The resulting reaction product was a benzoxazine containing the compound represented by the following formula as the major product. GPC analysis revealed that the purity of the major product was 45.1%. [ka]

[0069] <Comparative Synthesis Example 3> A 500 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 43.8 g of maleic anhydride, 65.7 g of toluene, and 60.0 g of NMP and mixed. A solution of 40.0 g of polydiaminodiphenylmethane (WANAMINE MDA-60R, manufactured by WANHUA CHEMICAL GROUP CO., LTD.) dissolved in 60.0 g of NMP was added dropwise and allowed to react for 30 minutes. After adding 3.9 g of paratoluenesulfonic acid monohydrate, the reaction mixture was heated and the water produced by the dehydration condensation reaction was distilled off from the system. The reaction mixture was then heated to 105-120°C for 4 hours while the reaction mixture was continued. The reaction mixture was then cooled. The toluene in the reaction mixture was distilled off under reduced pressure, and the mixture was poured into 1450 g of water. The resulting crude crystals were recovered. The crude crystals were dissolved in methyl ethyl ketone (MEK) in an amount 2.3 times by mass relative to the crude crystals, and then poured into water in an amount 20 times by mass. The precipitated solid was dried in vacuum at 70-80°C to obtain a reaction product (MI1). The obtained reaction product was maleimide represented by the following formula, and had an Mn of 520. [ka]

[0070] <Comparative Synthesis Example 4> A 300 mL reactor equipped with a condenser, Dean-Stark apparatus, and stirrer was charged with 20.7 g of maleic anhydride, 117.3 g of toluene, and 30.0 g of N-methylpyrrolidone (NMP) and mixed. A solution of 20.0 g of the aniline-formaldehyde condensate synthesized in Synthesis Example 4 dissolved in 30.0 g of NMP was added dropwise to the reaction mixture and allowed to react for 30 minutes. After adding 1.8 g of paratoluenesulfonic acid monohydrate, the reaction mixture was heated and the water produced by the dehydration condensation reaction was distilled off from the system. The reaction mixture was then cooled. The toluene in the reaction mixture was distilled off under reduced pressure, and the mixture was diluted with 117.3 g of methyl ethyl ketone (MEK). To this solution, 120.0 g of water was added, stirred, and allowed to stand to separate and remove the aqueous layer. This was repeated once, and then 60.0 g of water was added, stirred, and allowed to stand to separate and remove the aqueous layer. The resulting organic layer was then diluted with 57.5 g of MEK. Further, 60.0 g of water was added to this solution, and this was repeated twice: stirring at 45-55°C, allowing to stand, and then separating and removing the aqueous layer. The resulting organic layer was then concentrated using a rotary evaporator to obtain a solution of approximately 70% by mass. This solution was poured into 708 g of methanol, and the precipitated solid was collected and dried in vacuo at 80°C to obtain the reaction product (MI2). The resulting reaction product was maleimide represented by the formula described in Comparative Synthesis Example 3, with an Mn of 660.

[0071] <Examples 1 to 5 and Comparative Examples 1 to 4> Resin compositions of Examples 1 to 5 and Comparative Examples 1 to 4 were prepared according to the formulations shown in Table 1 below, and the solubility, moldability, glass transition temperature (Tg), and water absorption were evaluated or measured. Note that "BZO / CI" in the table refers to the mass ratio of benzoxazine (BZO) to citraconic imide (CI), but in Comparative Examples 2 and 3, it refers to the mass ratio of benzoxazine (BZO) to maleimide (MI).

[0072] [Table 1]

[0073] As shown in Table 1, the resin compositions of Examples 1 to 5, which used the allyl group-containing benzoxazine BZO1 in combination with citraconic imides CI1 and CI2, exhibited significantly improved glass transition temperatures in the cured products compared to the resin composition of Comparative Example 1, which used the allyl group-containing benzoxazine BZO1 alone. Furthermore, Comparative Examples 2 and 3, which used similar maleimides MI1 and MI2 instead of citraconic imides CI1 and CI2, exhibited poor solvent solubility. However, Examples 1 to 5, which used the citraconic imides CI1 and CI2 in combination, exhibited better solvent solubility and superior moldability than Comparative Examples 2 and 3. Furthermore, Examples 1 to 5 also exhibited excellent low water absorption. Furthermore, Comparative Example 4, which used benzoxazine BZO3, which does not have an allyl group, exhibited poor moldability compared to Examples 1 to 5, and a satisfactory cured product could not be obtained.

[0074] <Examples 6 to 9 and Comparative Examples 5 to 9> Resin compositions of Examples 6 to 9 and Comparative Examples 5 to 9 were prepared according to the formulations shown in Table 2 below, and the solubility, moldability, glass transition temperature (Tg), and water absorption were evaluated or measured. Note that "BZO / CI" in the table refers to the mass ratio of benzoxazine (BZO) to citraconic imide (CI), except for Comparative Example 6, where it refers to the mass ratio of benzoxazine (BZO) to maleimide (MI).

[0075] [Table 2]

[0076] As shown in Table 2, the resin compositions of Examples 6 to 9, which used a combination of allyl group-containing benzoxazine BZO2 and citraconic imide CI1, exhibited significantly improved glass transition temperatures in the cured products compared to the resin composition of Comparative Example 5, which used only allyl group-containing benzoxazine BZO2. Furthermore, Comparative Example 6, which used a similar substance, maleimide MI1, instead of citraconic imide CI1, exhibited poor solvent solubility, whereas Examples 6 to 9, which also used citraconic imide CI1, exhibited better solvent solubility than Comparative Example 6. Furthermore, the resin composition of Comparative Example 7, which used another allyl group-containing compound (Allyl 1) instead of allyl group-containing benzoxazine BZO2, exhibited good solvent solubility and moldability, and a cured plate could be obtained; however, its Tg was significantly lower than that of the other examples. Furthermore, the resin composition of Comparative Example 8, which used another allyl group-containing compound (Allyl 2) instead of allyl group-containing benzoxazine BZO2, exhibited poor solvent solubility due to the addition of catalyst 2E4MZ. Furthermore, the resin composition of Comparative Example 9, which used benzoxazine BZO4 having no allyl group, had poor moldability, and a satisfactory cured plate could not be obtained, and no test piece for measuring the glass transition temperature could be obtained.

[0077] The various numerical ranges described in this specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in this specification. Furthermore, a numerical range described as "X to Y" means from X to Y.

[0078] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their omissions, substitutions, modifications, etc. are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents. [Industrial Applicability]

[0079] The resin composition according to this embodiment can be used, for example, as a printed circuit board material, a semiconductor sealing resin, a matrix resin for composite materials, a paint, an adhesive, and the like.

Claims

1. The compound includes a compound represented by the following general formula (1) and a citraconic acid imide represented by the following general formula (2), 【Chemical 1】 In formula (1), R １ represents a divalent hydrocarbon group having 1 to 100 carbon atoms which may contain a heteroatom, R ２ and R ３ each independently represents an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ each independently represents a hydrogen atom or a methyl group, R ６ and R ７ each independently represents a methyl group or an ethyl group, p and q each independently represent an integer of 0 to 2, 【Chemistry 2】 In formula (2), R ８ each independently represents an alkyl group having 1 to 3 carbon atoms; each m independently represents an integer of 0 to 3; and n is the average number of repeating units and is a number greater than 0. Resin composition.

2. R in the formula (1) １ The resin composition according to claim 1, wherein is a divalent aromatic ring-containing hydrocarbon group having 6 to 50 carbon atoms which may contain a heteroatom.

3. The compound represented by formula (1) is represented by the following general formula (1A): 【Chemistry 3】 In formula (1A), R １１ is a single bond, -CH ２ -, -CH(CH ３ ) -, -C(CH ３ ) ２ represents - or -O-, and R １２ and R １３ each independently represents a methyl group or an ethyl group, s and t each independently represent an integer of 0 to 4, R ２ and R ３ each independently represents an alkanediyl group having 1 to 10 carbon atoms, R ４ and R ５ each independently represents a hydrogen atom or a methyl group, R ６ and R ７ each independently represents a methyl group or an ethyl group, and p and q each independently represent an integer of 0 to 2. The resin composition according to claim 1 .

4. The resin composition according to claim 1, wherein n in the formula (2) is 0.10 to 15.

0.

5. The resin composition according to any one of claims 1 to 4, which is used as a printed circuit board material.

6. A cured product obtained by curing the resin composition according to any one of claims 1 to 4.

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