KR102601953B1 - Maleimide resin mold, method for manufacturing maleimide resin mold, maleimide resin composition, and cured product thereof - Google Patents

Abstract

High-reliability semiconductor sealing materials, electrical and electronic component insulating materials, various composite materials including laminated boards (printed wiring glass fiber reinforced composite materials) and CFRP (carbon fiber reinforced composite materials), various adhesives, various paints, and structural applications. It is provided for maleimide resin molded bodies, maleimide resin compositions, and cured products thereof that are useful for materials, etc., have excellent workability and productivity, and are less exposed to the environment. The maleimide resin molded body contains maleimide resin and an organic solvent and is in the form of a film or flake.

Description

Maleimide resin molded body, manufacturing method of maleimide resin molded body, maleimide resin composition and cured product thereof {MALEIMIDE RESIN MOLD, METHOD FOR MANUFACTURING MALEIMIDE RESIN MOLD, MALEIMIDE RESIN COMPOSITION, AND CURED PRODUCT THEREOF}

The present invention relates to a maleimide resin molded body, a method for producing the maleimide resin molded body, a maleimide resin composition, and a cured product thereof. Specifically, applications include high-reliability semiconductor sealants, electrical and electronic component insulating materials, various composite materials including laminated boards (printed wiring glass fiber reinforced composite materials) and CFRP (carbon fiber reinforced composite materials), various adhesives, and various other composite materials. It relates to a maleimide resin molded body that is useful for paint applications, structural members, etc., has excellent workability and productivity, and has low environmental exposure, a method for manufacturing the maleimide resin molded body, a maleimide resin composition, and a cured product thereof.

Maleimide resin is a compound that has heat resistance exceeding that of an epoxy resin, has moldability equivalent to that of an epoxy resin, and also has the properties of a low coefficient of linear expansion and a high Tg. Polymaleimide compounds can be crosslinked alone or reacted with various maleimide compounds or crosslinking agents to provide materials with excellent heat resistance and flame retardancy, and have been used for various purposes such as sealing materials, base materials, and insulating materials. In particular, high heat-resistant base materials, flexible substrate materials, high heat-resistant low dielectric materials, high heat-resistant CFRP materials (carbon fiber composite materials), and high heat-resistant sealing materials for vehicle-mounted SiC power devices require both very high heat resistance and formability. It is used for purposes.

Conventionally, since maleimide resins have self-reactivity, most of them are commercially available in the form of resin powders by extraction from crystal powder such as recrystallization or reprecipitation (see Patent Document 1), and when used, the powder falls apart. There were problems with not only workability and productivity, but also environmental contamination (contamination and inhalation into the human body). In addition, there is a problem that solvents, etc. are mixed during crystallization and precipitation and cannot be completely removed, and acetic acid used during manufacturing is mixed, and the bad smell of acetic acid remains in the manufactured product, which is a problem related to the safety of workers. . Against this background, there is a demand for maleimide molded articles excellent in workability, productivity, and environmental safety. For example, Patent Document 2 discloses a method of melting and drawing a maleimide resin solution using an evaporator.

Japanese Patent Publication No. 6-86425 Japanese Patent Publication No. 2009-001783

However, in Patent Document 2, there was no significant change at a small scale, but when the amount of synthesis was increased, a long time was required to distill off the solvent, so there was a risk that self-polymerization would proceed during that time. Therefore, in actual production, the risk of polymerization or gelation is very high, and there are problems in terms of formability, stability, and productivity, such as an increase in viscosity due to an increase in molecular weight and different characteristics for each production. In addition, if the solvent recovery temperature is lowered to suppress this polymerization, especially in the case of maleimide resins with a softening point of 50°C or higher, solvent removal becomes difficult and solvent residue increases (especially solvent residue exceeding 30,000 ppm). There are also safety problems, such as concerns about the formation of voids and cracks during molding, and exposure to workers. In addition, in the synthesis of these maleimide resins, substances that have an effect on the human body, such as acetic acid, toluene, and xylene, may be used, so solvent residue is a particular problem.

Therefore, the purpose of the present invention is to provide a maleimide resin molded body that has excellent workability and productivity and is less exposed to the environment.

As a result of intensive studies to solve the above problems, the present inventors found that workability, productivity, etc. are excellent, and environmental exposure is reduced by drawing out the molded body in the form of a film or flake rather than the conventional crystal or powder form, and the present invention has reached completion.

That is, the present invention:

[1] A maleimide resin molded body containing a maleimide resin and an organic solvent and being in the form of a film or flake,

[2] The maleimide resin molded body according to the preceding paragraph [1], wherein the content of the organic solvent is 30000 ppm or less,

[3] The maleimide resin molded body according to the preceding item [1] or [2], wherein the organic solvent is at least one selected from aromatic hydrocarbons, ketones, esters and ethers having 3 to 10 carbon atoms,

[4] The maleimide resin molded body according to any one of the preceding paragraphs [1] to [3], having a thickness of 10 μm to 3 mm,

[5] The maleimide resin molded body according to any one of the preceding items [1] to [4], wherein the maleimide resin is a novolak-type maleimide resin having a repeating unit with an average number of functional groups of 2 to 20,

[6] The maleimide resin molded body according to any one of the preceding clauses [1] to [5], wherein the maleimide resin has a softening point of 50 to 150°C,

[7] A method for producing a maleimide compound molded body in which a solution of a maleimide resin dissolved in an organic solvent is applied on the surface of a support and dried,

[8] The method for producing a maleimide compound molded body according to the preceding item [7], wherein the organic solvent is at least one selected from aromatic hydrocarbons, ketones, esters, and ethers having 3 to 10 carbon atoms,

[9] A method for producing a maleimide compound molded body according to the preceding clause [7] or [8], wherein the drying temperature is 80 to 200°C,

[10] A maleimide resin molded body obtained by the production method according to any one of the preceding paragraph [7] to [9],

[11] A maleimide resin composition comprising the maleimide resin molded body according to any one of the preceding paragraph [1] to [6] and the preceding paragraph [10],

[12] The maleimide resin composition according to the preceding item [11], further comprising at least one selected from a compound capable of crosslinking reaction with the maleimide resin and a curing accelerator,

[13] A cured product of the maleimide resin composition according to the preceding paragraph [11] or [12],

It's about.

Since the maleimide resin molded body of the present invention is molded in the form of a film or flake, the organic solvent content can be suppressed, and a maleimide resin molded body with excellent workability and productivity and less environmental exposure can be provided. Additionally, since the amount of organic solvent can be suppressed, the formation of voids or cracks during molding can be prevented.

Figure 1 is a diagram showing the molecular weight distribution of the maleimide resin solution (V1) at the end of the polymerization reaction obtained in Synthesis Example 2.
Figure 2 is a diagram showing the molecular weight distribution of the maleimide resin molded body (M1) obtained in Example 1.
Figure 3 is a diagram showing the molecular weight distribution of maleimide resin (B1) obtained in Comparative Example 1 after solvent distillation during mass synthesis.
Figure 4 is a diagram showing the quantitative amount of acetic acid in maleimide resin (C1) of Comparative Example 4.

Hereinafter, the present invention will be described in detail.

The maleimide resin molded body of the present invention contains a maleimide resin and an organic solvent, and is characterized in that it is molded into a film or flake shape.

Compared to maleimide resin, which has conventionally been generally supplied in crystalline or powder form, it can be supplied in the form of a film or flake form, so in terms of workability, problems such as dust do not occur and it is very easy to handle. That is, the maleimide resin molded body of the present invention can easily prepare a maleimide resin composition.

A resin molded body refers to a product in which a resin solution is applied to the surface of a support, the solvent is removed under superheated and dry conditions, and the shape is peeled off from the support while maintaining the shape, for example, in the form of a film, sheet, fiber, plate, or rod. etc. can be mentioned.

Here, the film form refers to the form of a sheet with an average thickness of 10 μm to 3 mm. Flake shape refers to a state in which a film-shaped molded body is crushed. In addition, the flake shape is not particularly limited as long as it is of a size that does not scatter like powder shape during handling, but specifically, the average of the long diameter portion is preferably 0.1 cm to 5 cm, and more preferably 0.1 to 3 cm. It is cm.

In addition, the average thickness can be obtained by overlapping a plurality of sheets or films, measuring 10 arbitrary points with a nozzle, and dividing the obtained thickness by the number of overlapping sheets.

Next, for convenience of explanation, the manufacturing method of the maleimide resin molded body of the present invention will be described.

The maleimide resin molded body of the present invention is formed by applying a solution of maleimide resin in an organic solvent (hereinafter also referred to as “maleimide resin solution” or “resin solution”) on the surface of a support and molding it into a film or sheet shape. Afterwards, it can be obtained by removing the solvent under heating conditions (if necessary under reduced pressure conditions) and peeling the film from the support. That is, the method for producing the maleimide resin molded body of the present invention is carried out by the steps of applying the resin solution onto the surface of the support, drying it by heating, and peeling it from the support.

(maleimide resin)

As the maleimide resin that can be used in the present invention, known ones can be used, but from the viewpoint of viscosity and softening point, a novolak-type maleimide resin having a repeating unit with an average number of functional groups of 2 to 20 is preferable.

As a maleimide resin that can be used in the present invention, for example, it has a structure represented by the following formula (1).

(In the formula, R, which exists in plural, each exists independently and represents a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, or a phenyl group. Indicates n≤5.)

Alternatively, mixtures of maleimide resins may also be mentioned, but the present invention is not limited to these.

The manufacturing method of the maleimide resin represented by the above formula (1) is not particularly limited, and the maleimide resin may be manufactured by any known method for synthesizing the maleimide resin. As a specific manufacturing method, it is preferable to use a method such as that described in Japanese Patent Application Laid-Open No. 2009-001783, for example.

(maleimide resin solution)

The maleimide resin solution in the present invention means that the maleimide resin is dissolved in an organic solvent.

The maleimide resin solution is not particularly limited as long as it is a maleimide resin dissolved in an organic solvent. In addition to a polymer solution synthesized by a known solution polymerization method or various controlled polymerization methods, it may be a solution in which a portion of the solid polymer is precipitated during polymerization. The polymer may be precipitated by adding a precipitant to the solution in which polymerization has been completed.

The organic solvent that can be used is not particularly limited, and for example, at least one organic solvent selected from aromatic hydrocarbons, ketones, esters, and ethers having 3 to 10 carbon atoms is preferable. Additionally, it is preferable to subject the reaction liquid after polymerization to treatment such as washing with water.

The amount of the organic solvent used is usually 10 to 70% by weight, preferably 15 to 70% by weight, in the mixture of the maleimide resin and the above solvent.

Maleimide resins having melting points and softening points can be used. In particular, when it has a melting point, it is preferably 200°C or lower, and when it has a softening point, it is preferably between 50 and 150°C.

The viscosity of the maleimide resin solution (cone plate method, melt viscosity at 150°C) is preferably 5.0 mPa·s to 10000 Pa·s, more preferably 10 mPa·s to 100 Pa·s, and especially 10 mPa·s to 10 Pa·s. desirable. It is preferable that the melt viscosity at 150°C in the corn plate method is 10000 Pa·s or less because coating workability will not deteriorate.

(Process of applying on the surface of the support)

Next, the obtained maleimide resin solution is applied to the surface of the support and molded into a film or sheet.

The support on which the maleimide resin solution is applied is not particularly limited as long as it has a smooth surface, but preferably includes metal, PET film without mold release treatment, imide film, etc.

It is preferable that the film thickness and area when applied to the surface of the support are 10 ㎛ to 3 mm in dry film thickness and 100 cm 2 or less in area per 100 cm 2 of the surface of the support, respectively.

The WET film thickness of the film at the time of application is preferably 10 μm to 5 mm, more preferably 10 μm to 4.5 mm, and especially preferably 200 μm to 4.3 mm. If it exceeds the above range, the residual solvent reduction effect may not be sufficiently obtained, and if it falls below the range, the productivity of the maleimide resin molded product may be lowered.

(Heating and drying process and peeling process from the surface of the support)

Next, after applying the maleimide resin solution to the surface of the support, the solvent is removed under heat drying conditions (if necessary under reduced pressure conditions), and the dried film formed in a film or sheet form is peeled from the surface of the support. withdraw.

The drying temperature is preferably 80°C to 250°C, preferably 80°C to 200°C, and particularly preferably 100°C to 200°C. If the drying temperature exceeds 250°C, the resin tends to deteriorate, so it is set according to the required processing characteristics. Additionally, below 80°C, it is difficult to remove the solvent and the remaining amount of solvent increases, so voids and cracks are formed during molding, stickiness occurs, and the shape of the film cannot be maintained and peeling and pulverization may not be possible.

The film thickness of the film-like maleimide resin molded body peeled from the surface of the support and drawn out is not particularly limited, but is preferably 10 μm to 3 mm, more preferably 30 μm to 1 mm. If the film thickness exceeds 3 mm, the effect of reducing the amount of residual solvent is not sufficiently obtained.

Additionally, the obtained film-shaped maleimide resin molded body can be used as a flake-shaped maleimide resin molded body by pulverizing it.

The maleimide resin molded body obtained through the above process has a residual solvent of 30,000 ppm or less. Preferably it is 5000 ppm or less, more preferably 3000 ppm or less, especially preferably 1000 ppm or less, and especially preferably 600 ppm or less. Additionally, the lower limit of measurement detection limit is 5 ppm.

Additionally, it is preferable that the obtained maleimide resin molded body is soluble in solvents. Completely dissolved means that the maleimide resin is not undergoing a molecular weight increase reaction.

Since the maleimide resin molded body obtained in this way is superior in workability and productivity compared to the maleimide resin supplied in the conventional crystal form or powder form, a maleimide resin composition can be easily prepared.

Next, the maleimide resin composition of the present invention is explained.

The maleimide resin composition of the present invention may include a compound capable of crosslinking reaction with the maleimide resin molded body. The crosslinkable compound causes a crosslinking reaction with the maleimide resin molded body and acts as a curing agent for the maleimide resin. Examples of crosslinkable compounds include compounds having an amino group, cyanate group, phenolic hydroxyl group, alcoholic hydroxyl group, allyl group, methallyl group, acrylic group, methacryl group, vinyl group, and conjugated diene group. For example, it is preferable to mix an amine compound when heat resistance is required, and a cyanate ester compound when dielectric properties are required. Since maleimide resin can self-polymerize, it can also be used alone.

A catalyst for curing (curing accelerator) can be added to the maleimide resin composition of the present invention as needed. For example 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2 -Imidazoles such as ethyl-4-methylimidazole, triethylamine, triethylenediamine, 2-(dimethylaminomethyl)phenol, 1,8-diaza-bicyclo(5,4,0)-7 -Amines such as undecene, tris(dimethylaminomethyl)phenol, and benzyl dimethylamine, phosphines such as triphenylphosphine, tributylphosphine, and trioctylphosphine, tin octylate, zinc octylate, and dibutyltindi. Organic metal salts such as maleate, zinc naphthenate, cobalt naphthenate, and tin oleate, metal chlorides such as zinc chloride, aluminum chloride, and tin chloride, organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide, and azobisiso. Examples include azo compounds such as butylonitrile and azobisdimethylvaleronitrile, mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, Lewis acids such as boron trifluoride, and salts such as sodium carbonate and lithium chloride. The mixing amount of the catalyst for curing is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, based on 100 parts by weight of the maleimide resin molded body of the present invention.

An organic solvent can be added to the maleimide resin composition of the present invention to form a varnish-like composition (hereinafter simply referred to as varnish). If necessary, the maleimide resin composition of the present invention is dissolved in a solvent such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone to prepare a maleimide resin composition. A cured product of the maleimide resin composition of the present invention is obtained by heat press molding the prepreg obtained by varnishing it, impregnating it with a base material such as carbon fiber, glass fiber, polyester fiber, polyamide fiber, alumina fiber, paper, etc. and heat drying. You can do this.

The solvent at this time usually accounts for 10 to 70% by weight, preferably 15 to 70% by weight, in the mixture of the maleimide resin composition of the present invention and the solvent. Additionally, if it is a liquid composition, a cured product of the maleimide resin composition containing carbon fiber can be obtained as is, for example, by the RTM method.

Additionally, the maleimide resin composition of the present invention can also be used as a modifier for a film-type composition. Specifically, it can be used when improving flexibility, etc. in the B-stage. This film-type resin composition is obtained as a sheet-like adhesive by applying the maleimide resin composition of the present invention as the maleimide resin composition varnish to a release film, removing the solvent under heating, and then performing B-staging. This sheet-like adhesive can be used as an interlayer insulating layer in a multilayer substrate or the like.

A prepreg can be obtained by heating and melting the maleimide resin composition of the present invention, reducing the viscosity, and impregnating reinforcing fibers such as glass fibers, carbon fibers, polyester fibers, polyamide fibers, and alumina fibers.

Additionally, a prepreg can be obtained by impregnating reinforcing fibers with the varnish and heating and drying them.

There is no particular limitation on the method of impregnating these reinforcing fibers with the maleimide resin composition of the present invention, but since a method without using a solvent is preferred, the maleimide resin composition of the present invention is heated to 60 to 110° C. The hot melt method of impregnating the material in the wet state is preferable.

The proportion of the maleimide resin composition in the resulting prepreg (reinforced fibers impregnated with the maleimide resin composition) depends on the type of the reinforcing fibers, but is usually 20% by weight or more and 80% by weight or less, preferably 25% by weight or more. 65% by weight or less, more preferably 30% by weight or more and 50% or less. If the ratio of the maleimide resin composition is greater than this range, the ratio of reinforcing fibers is relatively reduced, so that a sufficient reinforcing effect is not obtained. Conversely, if the maleimide resin composition is less, the moldability may be impaired.

This prepreg can be cured by a known method to make a final molded product. For example, prepregs can be laminated, pressurized at 2 to 10 kgf/cm2 in an autoclave, and heat-cured at 150°C to 200°C for 30 minutes to 3 hours to form a molded body. However, to further improve heat resistance, as a post-cure It can be made into a fiber-reinforced composite molded product by treating it for 1 to 12 hours while gradually heating the temperature in the temperature range of 180°C to 280°C.

The prepreg is cut into the desired shape, laminated with copper foil, etc. as necessary, and then the maleimide resin composition for a laminated sheet is cured by heating while applying pressure to the laminate using a press molding method, an autoclave molding method, a sheet winding molding method, etc., to obtain a laminated sheet. You can.

Additionally, a multi-layer circuit board can be obtained by forming a circuit on a laminated board made by overlapping copper foil on the surface, overlapping prepreg or copper foil, etc. on it, and repeating the above operation.

The cured prepreg of the present invention is used for lightweight, high-strength, and high-heat resistance applications, such as robot hands for transporting liquid crystal glass substrates, disks for silicon wafer transport, aerospace members, and automobile engine members. It can be widely applied.

Specific uses of the maleimide resin composition of the present invention include adhesives, paints, coating agents, molding materials (including sheets, films, FRP, etc.), insulating materials for electronic materials (printed boards, sealing materials including wire coatings, etc., Examples include cyanate resin preparations for sealing materials and substrates, and additives to other resins, such as acrylic acid ester resins, as curing agents for resists. Particularly in FRP applications, solvent-free use has been greatly promoted in recent years due to concerns about environmental considerations and exclusion of defects due to voids. In addition, due to problems such as voids during molding, molding defects, and reduced voltage resistance, there are environments in which solvents cannot enter during the process even in semiconductor sealing applications.

(Example)

The content of the present invention will be described in detail below based on examples, but the present invention is not limited thereto. In addition, in the text, “part” and “%” represent “part by weight” and “% by weight”, respectively, unless otherwise specified. In the examples, softening point and melt viscosity were measured by the following methods.

·Softening point: Measured using a method based on JISK-7234

· Melt viscosity: Viscosity at 150°C by corn plate method

Quantification of the amount of residual solvent was performed using a gas chromatography GC-2010 manufactured by Shimadzu Seisakusho, and a DB-WAX (manufactured by Agilene Technologies) column with a length of 30 m and an inner diameter of 0.25 mm was used.

The temperature increase program uses a program that maintains the temperature at 70°C for 5 minutes, raises the temperature to 140°C at a temperature increase rate of 10°C/min, raises the temperature to 220°C at a temperature increase rate of 20°C/min, and maintains the temperature at 220°C for 5 minutes. did.

· Gel permeation chromatography (GPC LC-20AD manufactured by Shimadzu Seisakusho Co., Ltd.) was used to acquire molecular weight data. KF-603, KF-602.5, KF-602, and KF-601 were used as columns, the column temperature was 40°C, the mobile phase was THF, and measurement was performed with an RI detector under the conditions of a flow rate of 0.5 ml/min.

(Synthesis Example 1)

559 parts of aniline and 500 parts of toluene were added to a flask equipped with a thermometer, cooling pipe, Dean-Stark azeotropic distillation trap, and stirrer, and 167 parts of 35% hydrochloric acid were added dropwise over 1 hour at room temperature. After the dropwise addition was completed, the water and toluene that had been heated and azeotropically separated were cooled and separated, and then only the toluene, which was the organic layer, was returned to the system and dehydrated. Next, 251 parts of 4,4'-bis(chloromethyl)biphenyl was added over 1 hour while maintaining the temperature at 60 to 70°C, and the reaction was performed at the same temperature for an additional 2 hours. After completion of the reaction, toluene was distilled off while the temperature was raised, the system temperature was adjusted to 190-200°C, and the reaction was carried out at this temperature for 15 hours. Afterwards, while cooling, 500 parts of a 30% aqueous solution of sodium hydroxide was added dropwise slowly to prevent the system from violently refluxing, and the toluene distilled off at 80°C or lower was returned to the system and allowed to stand at 70°C to 80°C. The separated lower aqueous layer was removed, and the reaction solution was washed repeatedly until the washing solution became neutral. Next, excess aniline and toluene were distilled off from the oil layer under heating and reduced pressure to obtain 335 parts (A1) of aromatic amine resin. The softening point of the aromatic amine resin (A1) was 59°C and the melt viscosity was 0.05 Pa·s.

(Synthesis Example 2)

88 parts of maleic anhydride and 300 parts of toluene were added to a flask equipped with a thermometer, cooling tube, Dean-Stark azeotropic distillation trap, and stirrer. After heating and azeotropic water and toluene were cooled and separated, only the organic layer, toluene, was introduced into the system. It was returned and dehydrated. Next, a resin solution prepared by dissolving 116 parts of aromatic amine resin (A1) in 116 parts of N-methyl-2-pyrrolidone was added dropwise over 1 hour while maintaining the temperature of the system at 80 to 85°C. After completion of the dropwise addition, the reaction was carried out at the same temperature for 2 hours, 2 parts of p-toluenesulfonic acid were added, the condensation water and toluene azeotropically mixed under reflux conditions were cooled and separated, and then only the toluene, which was the organic layer, was returned to the system and dehydrated. The reaction was carried out for 10 hours. After completion of the reaction, 120 parts of toluene was added, washing with water was repeated to remove p-toluenesulfonic acid and excess maleic anhydride, and water was removed from the system by azeotropy by heating. The reaction solution was then concentrated to obtain a maleimide resin solution (V1) containing 70% maleimide resin. As a result of measuring the molecular weight distribution of the obtained maleimide resin solution (V1) by GPC, the results shown in FIG. 1 were obtained.

(Synthesis Example 3)

559 parts of aniline and 500 parts of toluene were added to a flask equipped with a thermometer, cooling pipe, Dean-Stark azeotropic distillation trap, and stirrer, and 167 parts of 35% hydrochloric acid were added dropwise over 1 hour at room temperature. After the dropwise addition was completed, the water and toluene that had been heated and azeotropically separated were cooled and separated, and then only the toluene, which was the organic layer, was returned to the system and dehydrated. Next, 175 parts of 4,4'-bis(chloromethyl)benzene was added over 1 hour while maintaining the temperature at 60 to 70°C, and the reaction was performed at the same temperature for another 2 hours. After completion of the reaction, toluene was distilled off while the temperature was raised, the system temperature was adjusted to 190-200°C, and the reaction was carried out at this temperature for 15 hours. Afterwards, while cooling, 500 parts of a 30% aqueous sodium hydroxide solution was slowly added dropwise to prevent the system from violently refluxing, and the toluene distilled off at 80°C or lower was returned to the system and allowed to stand at 70°C to 80°C. The separated lower aqueous layer was removed, and the reaction solution was washed repeatedly until the washing solution became neutral. Next, excess aniline and toluene were distilled off from the oil layer under heating and reduced pressure to obtain 280 parts (A2) of aromatic amine resin. The aromatic amine resin (A2) was semi-solid and dendritic.

(Synthesis Example 4)

88 parts of maleic anhydride and 300 parts of toluene were added to a flask equipped with a thermometer, cooling tube, Dean-Stark azeotropic distillation trap, and stirrer. After heating and azeotropic water and toluene were cooled and separated, only the organic layer, toluene, was introduced into the system. It was returned and dehydrated. Next, a resin solution in which 91.7 parts of aromatic amine resin (A2) was dissolved in 91.7 parts of N-methyl-2-pyrrolidone was added dropwise over 1 hour while maintaining the temperature of the system at 80 to 85°C. After completion of the dropwise addition, the reaction was carried out at the same temperature for 2 hours, 2 parts of p-toluenesulfonic acid were added, the condensation water and toluene azeotropically mixed under reflux conditions were cooled and separated, and then only the toluene, which was the organic layer, was returned to the system and dehydrated. The reaction was carried out for 10 hours. After completion of the reaction, 120 parts of toluene was added, washing with water was repeated to remove p-toluenesulfonic acid and excess maleic anhydride, and water was removed from the system by azeotropy by heating. The reaction solution was then concentrated to obtain a maleimide resin solution (V2) containing 70% maleimide resin.

(Example 1) (Support: imide film)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness: 200 μm) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. The solvent was removed by drying the resulting resin film at 180°C for 15 minutes.

The obtained maleimide resin molded body was in the form of a film with a thickness of 125 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M1) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M1) was 0.236% (2360 ppm). As a result of measuring the molecular weight distribution of the obtained maleimide resin molded body (M1) by GPC, the results shown in FIG. 2 were obtained. When compared with the molecular weight distribution measured by GPC (Figure 1) of the maleimide resin solution (V1) obtained in Synthesis Example 2, no change in molecular weight distribution was observed due to this process (measured by GPC).

(Example 2) (Support: imide film)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness: 200 μm) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. The solvent was removed by drying the resulting resin film at 200°C for 15 minutes.

The obtained maleimide resin molded body was in the form of a film with a thickness of 125 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M2) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M2) was 0.293% (2930 ppm). Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 3) (Support: imide film)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness: 200 μm) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. The solvent was removed by drying the resulting resin film at 200°C for 10 minutes.

The obtained maleimide resin molded body was in the form of a film with a thickness of 125 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M3) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M3) was 0.398% (3980 ppm). Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 4) (Support: imide film)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness: 200 μm) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. The solvent was removed by drying the resulting resin film at 200°C for 5 minutes.

The obtained maleimide resin molded body was in the form of a film with a thickness of 125 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M4) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M4) was 0.0901% (901 ppm).

Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 5) (Support: SUS plate)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied to a SUS plate (WET film thickness: 200 μm) using an applicator, and the applied resin film was dried at 180°C for 15 minutes to remove the solvent.

The obtained maleimide resin molded body was in the form of a film with a thickness of 113 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M5) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M5) was 0.163% (1638 ppm).

Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 6) (Support: SUS plate)

The maleimide resin solution (V2) obtained in Synthesis Example 4 was softly applied to a SUS plate (WET film thickness: 200 μm) using an applicator, and the applied resin film was dried at 180°C for 15 minutes to remove the solvent.

The obtained maleimide resin molded body was in the form of a film with a thickness of 113 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M6) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M6) was 0.3%≤(3000ppm≤). Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 7) (Support: Mirror copper foil)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied to the mirror surface of an electrolytic copper foil (18μ electrolytic copper foil CF-T9FZ-HTE, manufactured by Fukuda Kinzoku Hakubun Kogyo Co., Ltd.) using an applicator (WET film thickness: 200 μm). ), and the solvent was removed by drying the applied resin film at 180°C for 15 minutes.

The obtained maleimide resin molded body was in the form of a film with a thickness of 152 µm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M7) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M7) was 0.0728% (728 ppm).

Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Example 8) (Support: PET film)

The maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness 200 μm) to a PET film (Lumirror 38-S10 manufactured by Panac Co., Ltd.) that had not been subjected to release treatment using an applicator. The solvent was removed by drying the applied resin film at 160°C for 1 hour.

The obtained maleimide resin molded body was in the form of a film with a thickness of 146 μm, and was peeled and pulverized to obtain a flake-shaped maleimide resin molded body (M8) of the present invention.

The residual solvent in the obtained maleimide resin molded body (M8) was 0.0571% (571 ppm). Additionally, no change in molecular weight distribution was observed due to this process (measurement by GPC).

(Comparative Example 1)

The solvent was distilled off from 300 mL of the maleimide resin solution (V1) obtained in Synthesis Example 2 at 160°C under heating and reduced pressure using a rotary evaporator, and maleimide resin (B1) was obtained in the form of a resin block. As a result of measuring the molecular weight distribution of the obtained maleimide resin (B1) by GPC, the results shown in FIG. 3 were obtained. As a result of comparing the molecular weight distribution (Figure 1) of the maleimide resin solution (V1) obtained in Synthesis Example 2 by GPC, it was found that the maleimide resin (B1) after solvent distillation during mass synthesis had a high molecular weight. Confirmed. The residual solvent of the obtained maleimide resin (B1) was 0.1% (1000 ppm) or less.

(Comparative Example 2)

The solvent was distilled off from 1.0 L of the maleimide resin solution (V1) obtained in Synthesis Example 2 at 180°C under heating and reduced pressure using a rotary evaporator, and it was confirmed that the solution was gelled. The obtained maleimide resin (B2) lost fluidity.

<Comparison of drying temperatures in manufacturing methods of maleimide resin molded articles>

(Comparative Example 3)

As in Example 1, the maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. 200 μm), and the solvent was removed by heating and drying the applied resin film with hot air at 50°C for 1 hour.

The obtained maleimide resin molded body was sticky and could not maintain the shape of the film, so it could not be peeled and pulverized.

(Comparative Example 4)

As in Example 1, the maleimide resin solution (V1) obtained in Synthesis Example 2 was softly applied (WET film thickness) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator. 200 μm), and the solvent was removed by heating and drying the applied resin film with hot air at 250°C for 1 hour.

The obtained maleimide resin molded body was in the form of a film and could be peeled off to form flakes, but its molecular weight progressed and it became insoluble in various solvents such as acetone.

<Comparison of odor>

(Example 9, Comparative Example 5)

The maleimide resin molded body (M1) obtained in Example 1 and 4,4'-bismaleimide diphenylmethane (hereinafter referred to as C1, manufactured by TCI) were prepared for comparison, and the odor was compared.

In addition, the quantification of acetic acid was performed using a gas chromatography GC-2010Plus manufactured by Shimadzu Seisakusho, and DB-WAX (manufactured by Agilene Technologies) with a length of 30 m and an inner diameter of 0.25 mm was used as a column. The temperature increase program was used to maintain the temperature at 60°C for 7 minutes, increase the temperature to 220°C at a temperature increase rate of 20°C/min, and maintain the temperature at 220°C for 5 minutes.

As a result, it was confirmed that the bad smell of acetic acid was present in Comparative Example 5, and no bad smell was felt in Example 9.

Additionally, as a result of measurement using gas chromatography, acetic acid was detected in Comparative Example 5 (see FIG. 4, retention time 11.298 minutes). Additionally, as a result of measuring the acid value, it was confirmed that the acid value was 10 mgKOH/g, equivalent to 1% of acetic acid.

<Comparison of shape and solvent solubility>

(Examples 10 to 14, Comparative Examples 6 and 7)

Using the maleimide resin molded bodies (M1, M5 to M8) obtained in Examples 1, 5, 6, 7, and 8, the maleimide resin C1 for comparison, and the maleimide resin (B2) described in Comparative Example 2, A dissolution test was performed.

As a result of examining the resin concentration at 50%, the maleimide resin molded bodies M1, M5 to M8 were completely dissolved, but the maleimide resin (C1) and the maleimide resin (B2) were not completely dissolved.

From the above, it can be seen that in Examples 10 to 14, since the maleimide resin molded bodies (M1, M5 to M8) were completely dissolved, the high molecular weight reaction did not proceed. On the other hand, since complete dissolution was not possible in Comparative Examples 6 and 7, it can be seen that the maleimide resin (C1, B2) is undergoing a high molecular weight conversion reaction.

<Preparation of maleimide resin compositions and comparison of cured product properties>

(Example 15)

Mix 10 parts of the maleimide resin molded body (M1) obtained in Example 1 and 0.21 parts of 2-ethyl-4-methylimidazole (2E4MZ Shikoku Kasei Co., Ltd.) as a curing accelerator and mix uniformly by stirring. - Kneaded and obtained the maleimide resin composition of the present invention. This maleimide resin composition was softly applied (WET film thickness: 200 μm) to a commercially available imide film (“Kapton (registered trademark) 100H” manufactured by Toray DuPont) using an applicator, and the applied resin film was cured under curing conditions of 160°C A cured product was obtained by curing while removing the solvent at 2h + 180°C x 6h. Table 1 shows the results of evaluating the physical properties of the obtained cured product.

(Comparative Example 8)

61 parts EPPN-502H (Nippon Kayaku, epoxy equivalent 169 g/e.q., softening point 67.5°C EP1), 38 parts by weight of phenol novolak (H-1, Meiwa Kasei, hydroxyl equivalent 106 g/e.q.), triphenylphosphine (TPP) 1 part by weight of Junsei Chemical reagent) was mixed and uniformly mixed and kneaded using a mixing roll to obtain an epoxy resin composition. After tabletting this epoxy resin composition, a resin composition molded body was prepared by transfer molding, and a cured product was obtained under curing conditions of 160°C x 2h + 180°C x 6h. The following physical properties of the obtained cured product were evaluated. The results are shown in Table 1.

(Comparative Example 9)

65 parts of EOCN-1020-55 (Nippon Kayaku, epoxy equivalent, 194 g/e.q., softening point, 54.8°C EP2), 34 parts by weight of phenol novolak (H-1, Meiwa Kasei, hydroxyl equivalent, 106 g/e.q.), TPP (Junsei) 1 part by weight of Kagaku reagent was mixed and uniformly mixed and kneaded using a mixing roll to obtain an epoxy resin composition. After tabletting this epoxy resin composition, a resin composition molded body was prepared by transfer molding, and a cured product was obtained under curing conditions of 160°C x 2h + 180°C x 6h. The following physical properties of the obtained cured product were evaluated. The results are shown in Table 1.

The following measurements were performed on the obtained cured product.

·DMA

Measurement items: storage modulus at 30℃, 200℃, 250℃,

: Glass transition temperature (temperature at maximum tanδ)

Measurement method: Dynamic viscoelasticity meter TA-instruments product, Q-800

Measurement temperature range: 30℃∼350℃

Temperature increase rate: 2℃/min

Test piece size: cut to 5 mm x 50 mm was used (thickness was approximately 800 μm).

From Table 1, it can be seen that the cured product of the maleimide resin composition of the present invention can be molded under the same curing conditions as epoxy resin, and the obtained cured product has less change in elastic modulus at high temperature compared to the case of using a high heat-resistant epoxy resin. Able to know.

Although the present invention has been described in detail with reference to specific forms, it is clear to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention.

In addition, this application is based on the Japanese patent application (Japanese patent application 2016-169417) filed on August 31, 2016, and is incorporated by reference in its entirety. Additionally, all references cited herein are taken in their entirety.

The maleimide resin molded body of the present invention can easily prepare a maleimide resin composition, and is used for high heat-resistant substrate materials, flexible substrate materials, high heat-resistant low dielectric materials, high heat-resistant CFRP materials (carbon fiber composite materials), and vehicle mounting. It is very useful for a wide range of applications, such as high heat-resistant sealing materials for SiC power devices.

Claims (14)

A maleimide resin molded body in the form of a film or flake containing only a novolak-type maleimide resin that has a repeating unit with an average number of functional groups of 2 to 20 and is not crosslinked with a crosslinking agent and an organic solvent. The maleimide resin molded body is capable of crosslinking reaction. A maleimide resin molded body that is mixed with a compound to form a maleimide resin composition. According to claim 1,
A maleimide resin molded body in which the maleimide resin has a structure represented by the following formula (1).

(In Formula (1), multiple R exist independently and represent a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, or a phenyl group. X is selected from the following structural formulas (a) to (e). n is the average value and indicates 1<n≤5.)
The method of claim 1 or 2,
A maleimide resin molded body having a content of the organic solvent of 5 ppm or more and 30,000 ppm or less. The method of claim 1 or 2,
A maleimide resin molded body wherein the organic solvent is at least one selected from aromatic hydrocarbons, ketones, esters, and ethers having 3 to 10 carbon atoms. The method of claim 1 or 2,
Maleimide resin molded body with a thickness of 10㎛ to 3㎜. The method of claim 1 or 2,
A maleimide resin molded body wherein the softening point of the maleimide resin is 50 to 150°C. A method for producing a maleimide resin molded body in which a solution of only a novolak-type maleimide resin having a repeating unit with an average number of functional groups of 2 to 20 and not crosslinked with a crosslinking agent is dissolved in an organic solvent and applied on the surface of a support, followed by drying. As, the maleimide resin molded body is mixed with a compound capable of crosslinking reaction to form a maleimide resin composition. According to claim 7,
A method for producing a maleimide resin molded body, wherein the maleimide resin has a structure represented by the following formula (1).

(In Formula (1), multiple R exist independently and represent a hydrogen atom, an alkyl group with 1 to 10 carbon atoms, or a phenyl group. X is selected from the following structural formulas (a) to (e). n is the average value and indicates 1<n≤5.)
According to claim 7 or 8,
A method for producing a maleimide resin molded body, wherein the organic solvent is at least one selected from aromatic hydrocarbons, ketones, esters, and ethers having 3 to 10 carbon atoms. According to claim 7 or 8,
A method for producing a maleimide resin molded body with a drying temperature of 80 to 200°C. A maleimide resin molded body obtained by the production method according to claim 7 or 8. A maleimide resin composition comprising the maleimide resin molded body according to claim 1 or 2. According to claim 12,
A maleimide resin composition further comprising at least one selected from a compound capable of crosslinking reaction with a maleimide resin and a curing accelerator. A cured product of the maleimide resin composition according to claim 12.