Diamine monomer with side chain containing tert-butyl and preparation method and application thereof

Abstract

The invention discloses a diamine monomer with a side chain containing tertiary butyl and a preparation method and application thereof.The diamine monomer is special in structure, polyesteramide or polyimide can be prepared through reaction of the diamine monomer and a tetracarboxylic acid derivative, the obtained polyesteramide is narrow in molecular weight distribution, the molecular chain is provided with the special structure introduced by the diamine monomer, and the molecular chain is not prone to being damaged. The resin prepared by the preparation method not only has good dissolution film-forming property, but also has excellent dielectric property and lower water absorption property, is high-performance resin, and is widely applied to the fields of communication electronics and aerospace.

Description

Technical Field

[0001] This invention relates to a diamine monomer with a tert-butyl side chain, its preparation method, and its application, belonging to the field of polymer compounds and their preparation technology. Background Technology

[0002] Polyimide is an important class of high-performance materials, initially developed for the aerospace industry. Its high thermal stability, coupled with excellent mechanical and electrical properties, makes it attractive in the microelectronics and optoelectronics industries as an interlayer dielectric, flexible circuit substrate, and stress buffer. With the miniaturization and weight reduction of microelectronic devices, low dielectric constant has become a key factor in minimizing power loss and signal transmission delay in microelectronic applications. However, commercially available polyimide films have relatively high dielectric constants (approximately 3.4-4.0 at 1 MHz), which is insufficient to meet application requirements. Furthermore, high-temperature processing is required in the fabrication of optoelectronic devices, necessitating good heat resistance in the polymer used as the substrate. On the other hand, the rigid structure of polyimide and its poor solubility due to strong intermolecular forces have been a technical challenge in its practical applications. Therefore, the vigorous development of advanced polyimide materials with good solubility, low dielectric constant, and high-temperature resistance is of great significance.

[0003] Existing research has shown that introducing twisted, non-coplanar, or large dangling structures into the polymer backbone can improve the thermal stability and solubility of polymers. Polyimides containing large steric hindrance and non-coplanar structures can disrupt the rigid chain structure and intermolecular forces of the backbone, hindering the stacking of molecular chains and thus yielding highly soluble polyimide materials. For example, Wang Chengyi et al. reported a method for preparing soluble polyimides with asymmetric meta-structures substituted with difluoromethylbenzene (CN202011579258.3); Liu Gang et al. developed an aromatic diamine monomer containing fluorene and pyridine heterocyclic structures that can effectively improve the solubility of polyimides in specific solvents (CN202011033259.8); and Huang Xiaohua et al. synthesized soluble polyimides containing tert-butyl and morpholino groups (CN104927054A). However, these existing technologies still suffer from performance degradation under humid and hot conditions, namely, high water absorption rate leads to an increase in dielectric constant. Therefore, it is essential to improve the dielectric stability of polyimide under humid and hot conditions. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a diamine monomer with tert-butyl groups in its side chains. This diamine monomer contains multiple benzene ring structures connected by ether bonds, and each benzene ring carries multiple tert-butyl groups with large free volumes. The benzene rings, with their highly symmetrical planar six-membered ring structure, provide a rigid framework for the polyimide. This rigid structure effectively hinders the disordered movement and deformation of the molecular chains at high temperatures. The ether bonds impart a certain degree of flexibility to the molecular chains, while the tert-butyl groups enhance the solubility of the polyimide. When this diamine is used to make polyimide, it improves the polyimide's solubility, film-forming properties, and dielectric properties, while reducing the dielectric constant, dielectric loss, and water absorption rate, thus possessing significant potential application value in the microelectronics field.

[0005] The specific technical solution of this invention is as follows: A diamine monomer with a tert-butyl side chain has the structure shown in formula (1): In formula (1), A is hydrogen, carboxyl, dimethyl, oxygen, phenyl or ethyl; when A is oxygen, it forms a carbonyl group.

[0006] In formula (1), R1 is hydrogen, methyl, tert-butyl, -F, -CF3, or -OH.

[0007] In formula (1), R2 is an alkylene group with 0 to 7 carbon atoms, preferably an alkylene group with 0 to 1 carbon atoms.

[0008] In equation (1), the positions of -NH2 and -R1 on the benzene ring are arbitrary.

[0009] Preferably, the diamine monomer containing a tert-butyl group in its side chain is selected from any one of the compounds shown in formulas (1-1) to (1-12): The present invention also provides a method for preparing the above-mentioned diamine monomer containing tert-butyl group in the side chain, the method comprising the following steps: (1-1) The compound with the structure shown in formula (2), the compound with the structure shown in formula (3), organic solvent I and a basic substance are mixed and reacted to obtain the intermediate product with the structure shown in formula (4); (1-2) Under a hydrogen atmosphere, the intermediate product with the structure shown in formula (4), organic solvent II and catalyst are mixed and reacted to obtain the above diamine monomer with tert-butyl side chain.

[0010] Furthermore, in the compounds with the structure shown in formula (2) and the compounds with the structure shown in formula (3), the definitions of A, R1 and R2 are consistent with those in formula (1).

[0011] Furthermore, when A is hydrogen, the compound with the structure shown in formula (3) is di(4-hydroxy-3,5-di-tert-butyl)benzane, and the products of formulas (1-1) to (1-8) above are synthesized from this raw material; when A is dimethyl, the compound with the structure shown in formula (3) is 4,4'-isopropylidene di[2,6-di-tert-butylphenol], and the products of formulas (1-9) to (1-10) above are synthesized from this raw material; when A is carboxyl, the compound with the structure shown in formula (3) is 2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)acetic acid, and the products of formulas (1-11) to (1-12) above are synthesized from this raw material.

[0012] Furthermore, in step (1-1), the molar ratio of the compound with the structure shown in formula (3) to the compound with the structure shown in formula (2) is 1:(2 to 2.3), for example 1:2, 1:2.1, 1:2.2, 1:2.3.

[0013] Furthermore, in step (1-1), the alkaline substance is at least one of sodium hydroxide, potassium hydroxide, sodium hydride, etc. The molar ratio of the compound with the structure shown in formula (3) to the alkaline substance is 1:(2.6~3.0), for example 1:2.6, 1:2.7, 1:2.8, 1:2.9, 1:3.0.

[0014] Furthermore, in step (1-1), the organic solvent I is at least one of N,N-dimethylacetamide, N,N-dimethylformamide, N-methylpyrrolidone, dimethyl sulfoxide, etc. Organic solvent I is the reaction medium, and its amount can be adjusted according to actual needs.

[0015] Further, in step (1-1), the mixture is heated to undergo a reflux reaction. The reaction temperature is generally between 100 and 120°C, for example, 100°C, 101°C, 102°C, 103°C, 104°C, 105°C, 106°C, 107°C, 108°C, 109°C, 110°C, 111°C, 112°C, 113°C, 114°C, 115°C, 116°C, 117°C, 118°C, 119°C, and 120°C. The reaction time is generally between 10 and 20 hours, for example, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, and 20 hours.

[0016] Furthermore, in step (1-1), after the reaction, the reaction solution is cooled, and then the reaction solution is added to water to precipitate the solid. The solid is collected, dried, and the intermediate product is obtained. The mass ratio of the reaction solution to water is 1:(3~10), for example, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10.

[0017] Furthermore, in steps (1-2), the catalyst is a commonly used catalyst for hydrogenation reactions, such as a noble metal catalyst like palladium on carbon. The amount of catalyst used is 1-5 wt% of the mass of the compound with the structure shown in formula (3), for example, 1%, 2%, 3%, 4%, or 5%.

[0018] Furthermore, in steps (1-2), organic solvent II is N,N-dimethylformamide (DMF), N-methylpyrrolidone, etc. Organic solvent II is the reaction medium, and its amount can be adjusted according to actual needs.

[0019] Furthermore, in steps (1-2), the hydrogen pressure is maintained at 0.2–0.4 MPa throughout the reaction. If the pressure falls below this range, hydrogen is introduced into the reactor to maintain the required pressure. The reaction ends when the hydrogen pressure no longer decreases. The reaction time is generally 4–8 hours, for example, 4 hours, 5 hours, 6 hours, 7 hours, or 8 hours.

[0020] Furthermore, in steps (1-2), the reaction temperature is 70-90℃, for example, 70℃, 75℃, 80℃, 85℃, or 90℃.

[0021] Further, in steps (1-2), after the reaction is complete, excess hydrogen gas is released, the reaction solution is added to water to precipitate a solid, the solid is collected, washed, and dried to obtain the final product. The mass ratio of the reaction solution to water is 1:(3~10), for example, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, or 1:10. The solid is washed with a mixture of methanol and water at a volume ratio of 20-40:60-80.

[0022] The present invention also provides a polyamic acid ester, wherein the polyamic acid ester is obtained by reacting at least one amine compound and at least one tetracarboxylic acid derivative to obtain polyamic acid, and then the polyamic acid is reacted with an esterification agent to obtain polyamic acid ester (PAE); wherein the amine compound includes a diamine, the diamine includes diamine A, and the diamine A is at least one of the above-mentioned diamine monomers having a tert-butyl side chain of formula (1).

[0023] Furthermore, the content of diamine A shown in formula (1) in the total diamine is 30-90 mol%, for example 30 mol%, 35 mol%, 40 mol%, 45 mol%, 50 mol%, 55 mol%, 60 mol%, 65 mol%, 70 mol%, 75 mol%, 80 mol%, 85 mol%, 90 mol, preferably 50-90 mol, more preferably 60-70 mol.

[0024] Furthermore, the diamine further includes diamine B, which is a diamine that does not have the structure shown in formula (1). Examples of diamine B include p-phenylenediamine, 3,5-diaminobenzoic acid, 1,4-bis(4-aminophenoxy)benzene, 1,5-naphthyldiamine, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 3,3'-dichlorobenzidine, 4,4'-bis(4-aminophenoxy)biphenyl, diaminodiphenylmethane, 4, The first one or more of the following: 4'-diaminodiphenyl ether, 2,2-diaminodiphenylpropane, 4,4'-diaminodiphenyl sulfone, diaminobenzophenone, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)diphenyl sulfone, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, and 1,3-bis(3-aminopropyl)tetramethyldisiloxane (SIDA).

[0025] Furthermore, the amine compound also includes a monoamine selected from one or more of aniline, 3-aminophenol, 4-ethynylaniline, phenylethynyltrifluoromethylaniline, 2-phenylethynylaniline, 4-aminobenzoic acid, 4-aminophenylmaleimide, 3-aminopropyltriethoxysilane, 4-(trifluoromethyl)aniline, 2-aminothiazole, and 4-amino-2,2,6,6-tetramethylpiperidine.

[0026] Furthermore, the content of the diamine in the amine compound is 90-100 mol%, for example, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%.

[0027] Furthermore, the molar amount of the monoamine is 0 to 10 mol% of the total molar amount of the amine compound, for example, 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, preferably 0 to 5%, and more preferably 2 to 5%.

[0028] Furthermore, the tetracarboxylic acid derivative is any one or more of tetracarboxylic dianhydride, tetracarboxylic monoanhydride, tetracarboxylic acid, dialkyl dicarboxylic acid ester, and dialkyl dicarboxylic acid acyl chloride ester.

[0029] Preferably, the tetracarboxylic acid derivative includes tetracarboxylic acid derivative A, which is selected from any one or more of the following: pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl) ether dianhydride, bis(3,4-dicarboxyphenyl) sulfone dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, and 3,3,4,4-diphenyl ether tetracarboxylic dianhydride.

[0030] Preferably, the tetracarboxylic acid derivative further includes tetracarboxylic acid derivative B, which may be selected from one or more of aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aromatic tetracarboxylic dianhydrides other than tetracarboxylic dianhydrides in which four carbonyl groups are directly bonded to the aromatic ring structure; it may also be selected from 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 4,4'-oxobisphthalic anhydride, and 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride. The dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,4-cyclohexanetetracarboxylic dianhydride, 2,3,5-tricarboxy-cyclopentylacetic dianhydride, 3,4-dicarboxy-1-cyclohexylsuccinic dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalesuccinic dianhydride, and bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic dianhydride, etc.

[0031] Furthermore, the content of the tetracarboxylic acid derivative A accounts for 80-100 mol% of the total amount of the tetracarboxylic acid derivative, for example, 80%, 85%, 90%, 95%, or 100%.

[0032] Furthermore, the molar ratio of the tetracarboxylic acid derivative to the total diamine is 1:0.8 to 1:1, for example, 1:0.8, 1:0.9, or 1:1.0. The closer this molar ratio is to 1:1, the larger the molecular weight of the resulting polyamic acid. If the molecular weight of the polyamic acid is too small, it will affect the strength of the coating film; conversely, if the molecular weight of the polyamic acid is too large, the viscosity of the resulting polyimide will become too high, resulting in poor workability and uniformity of the coating film.

[0033] Furthermore, the weight-average molecular weight of the obtained polyamic acid is 5,000 to 30,000, for example 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 17,000, 18,000, 19,000, 20,000, 21,000, 22,000, 23,000, 24,000, 25,000, 26,000, 27,000, 28,000, 29,000, 30,000, preferably 10,000 to 150,000.

[0034] Furthermore, the amine compound and the tetracarboxylic acid derivative react in a solvent. The solvent used in the above reaction is not particularly limited as long as it can dissolve the generated polyamic acid. The solvent can be any one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-ethylpyrrolidone, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, 1,3-dimethylimidazolinone, etc.; preferably, the solvent is at least one of N-methyl-2-pyrrolidone and γ-butyrolactone.

[0035] Furthermore, there are no particular requirements regarding the mixing order of the amine compound, the tetracarboxylic acid derivative, and the solvent. It is possible to mix the amine compound and the solvent first, and then add the tetracarboxylic acid derivative; or to mix the tetracarboxylic acid derivative and the solvent first, and then add the amine compound; or to add the tetracarboxylic acid derivative and the amine compound alternately in the solvent.

[0036] Furthermore, although the reaction can be carried out at any concentration, if the concentration is too low, it is difficult to obtain a high molecular weight polymer; if the concentration is too high, the viscosity of the reaction solution is too high, making it difficult to achieve uniform stirring. Therefore, it is preferable that the content of the reactant tetracarboxylic acid derivative and amine compound in the mixture of amine compound, tetracarboxylic acid derivative and solvent is 1-50 wt%, for example 1 wt%, 5 wt%, 10 wt%, 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt%, 45 wt%, 50 wt%, more preferably 5-30 wt%. The reaction can be carried out at a high concentration in the initial stage, and then the solvent can be added in the subsequent reaction process.

[0037] Furthermore, the reaction temperature of the amine compound and the tetracarboxylic acid derivative is 0–150°C, for example, 0°C, 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, and 150°C; preferably, the reaction temperature is 5–100°C. The higher the temperature, the faster the polymerization reaction ends; however, if the temperature is too high, it may sometimes be impossible to obtain a high molecular weight polymer.

[0038] Furthermore, the reaction solution containing polyamic acid obtained from the reaction can be directly used for the subsequent preparation of polyamic esters, or the polyamic acid can be extracted from the reaction solution and then used for the subsequent preparation of polyamic esters. 。 Adding a reaction solution containing polyamic acid to a stirred, unsuitable solvent will precipitate the polyamic acid. The unsuitable solvent is selected from one or more of methanol, acetone, hexane, ethylene glycol diethyl ether, heptane, methyl ethyl ketone, ethanol, and toluene. The precipitated polyamic acid is then washed and dried to obtain powdered polyamic acid.

[0039] Furthermore, the polyamic acid esterification step can be: mixing the prepared reaction solution containing polyamic acid, the esterification reagent, and the catalyst as described above, and reacting them; or mixing polyamic acid powder, the esterification reagent, the catalyst, and the solvent as described above, and reacting them. The solvent used is the same as that used in the preparation of polyamic acid.

[0040] Furthermore, the esterifying agent is selected from at least one of N,N-dimethylformamide dimethyl acetal, dimethyl sulfoxide dimethyl acetal, acetone dimethyl acetal, vinyl ethyl ether, and di-tert-butyl dicarbonate.

[0041] Furthermore, the catalyst is one of pyridine, 4-dimethylaminopyridine, acetic anhydride, dicyclohexylcarbodiimide (DCC), or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

[0042] Furthermore, the catalyst dosage is 5-30 wt% of the polyamic acid mass, specifically 5%, 10%, 15%, 20%, 25%, and 30%.

[0043] Furthermore, the mass ratio of polyamic acid to esterification reagent is 1:(0.05~0.2), for example 1:0.05, 1:0.1, 1:0.15, 1:0.2.

[0044] Furthermore, the esterification reaction temperature is 60~120℃, for example 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, 95℃, 100℃, 105℃, 110℃, 115℃, 120℃, and the time is 2~8h, for example 2h, 4h, 5h, 6h, 7h, 8h.

[0045] Furthermore, after the reaction, the resulting reaction solution containing polyamic acid ester contains residual catalyst. Therefore, to avoid the catalyst's influence on the photosensitive resin composition, it is preferable to add the reaction solution to a stirred, unsuitable solvent for precipitation and recovery. The precipitate obtained through the unsuitable solvent is washed and dried to obtain powdered polyamic acid ester. The unsuitable solvent used is the same as the unsuitable solvent used to precipitate the polyamic acid.

[0046] Furthermore, the molecular weight of the obtained polyamic acid ester, in terms of weight-average molecular weight (Mw), is preferably 10,000 to 50,000.

[0047] Furthermore, the viscosity of the obtained 5wt% polyamic acid ester solution is 5~30 mPa·s. The solution viscosity (mPa·s) is obtained by preparing a 5wt% solution of the polyamic acid ester using a good solvent (e.g., N-methyl-2-pyrrolidone, γ-butyrolactone, etc.) and then measuring its viscosity using a viscometer at 25±0.1℃.

[0048] The present invention also provides a photosensitive resin composition comprising the above-mentioned polyamic acid ester.

[0049] Furthermore, the photosensitive resin composition also includes a coupling agent. The coupling agent is selected from 3-aminopropyltrimethoxysilane, 3-aminopropyltriethylsilane, 2-aminopropyltrimethyltrimethylsilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureopropyltrimethoxysilane, 3-ureopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminoalkylpropyltriethylenetriamine, ethylene glycol diglycidyl ether, and polyethylene glycol diglycidyl ether. The following are some of the following: neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N,N,N'N'-tetraglycidyl-m-xylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N'N'-tetraglycidyl-4,4'-diaminodiphenylmethane, KBM-1403 (3-acryloyloxypropyltrimethoxysilane, Shin-Etsu Chemical Industry Co., Ltd.).

[0050] Furthermore, the photosensitive resin composition also includes a photosensitizer, which is a quinone diazide compound. Examples of photosensitizers include compounds obtained by bonding quinone diazide sulfonic acid to a polyhydroxy compound via an ester bond, compounds obtained by bonding quinone diazide sulfonic acid to a polyamino compound via a sulfonamide bond, and compounds obtained by bonding quinone diazide sulfonic acid to a polyhydroxy polyamino compound via an ester bond or a sulfonamide bond. At least 50 mol% of all functional groups in the aforementioned polyhydroxy and polyamino compounds are replaced by quinone diazide. Preferably, the quinone diazide compound is any one of 5-naphthoquinone diazidesulfonic acid group, 4-naphthoquinone diazidesulfonic acid group, and diazonaphthoquinone compound (DNQ).

[0051] Furthermore, the photosensitive resin composition also includes a solvent. The solvent is selected from one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 2-pyrrolidone, N-ethylpyrrolidone, N-ethylpyrrolidone, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, γ-butyrolactone, and 1,3-dimethylimidazolinone; preferably, the solvent is at least one of N-methyl-2-pyrrolidone and γ-butyrolactone.

[0052] Furthermore, in the photosensitive resin composition, the mass ratio of polyamic acid ester to coupling agent is 100:0.1~20, for example 100:0.1, 100:0.5, 100:1, 100:1.5, 100:2, 100:2.5, 100:3, 100:3.5, 100:4, 100:4.5, 100:5, 100:5.5, 100:6, 100:6.5, 100:7, 100:7.5, 100:8, 100:8.5, 100: 9, 100:9.5, 100:10, 100:10.5, 100:11, 100:11.5, 100:12, 100:12.5, 100:13, 100:13.5, 100:14, 100:14.5, 100:15, 100:15.5, 100:16, 100:16.5, 100:17, 100:17.5, 100:18, 100:18.5, 100:19, 100:19.5, 100:20.

[0053] Furthermore, in the photosensitive resin composition, the mass ratio of polyamic acid ester to photosensitizer is 1:0.05~1, for example 1:0.05, 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, or 1:1.

[0054] Furthermore, in the photosensitive resin composition, the amount of solvent ensures that the concentration of polyamic acid ester is 5-13 wt%, for example 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 11 wt%, 12 wt%, 13 wt%, preferably 8-11 wt%.

[0055] The present invention also provides a polyimide film made of the above-described photosensitive resin composition.

[0056] Furthermore, the polyimide film can be formed by coating a photosensitive resin composition onto a substrate and then curing it to obtain the polyimide film.

[0057] Furthermore, it is preferable to degas the photosensitive resin composition before coating. The degassing is preferably performed by static degassing. The static degassing temperature is preferably -20 to 0°C, for example -20°C, -15°C, -10°C, -5°C, 0°C, more preferably -20 to -10°C, and most preferably -20°C. The static time is preferably 6 to 30 hours, for example 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, 30 hours, and more preferably 12 to 24 hours.

[0058] Furthermore, the thickness of the photosensitive resin composition coating is preferably 2 to 10 μm, more preferably 2 to 6 μm.

[0059] Furthermore, the curing is preferably programmed temperature curing. The programmed temperature curing process is preferably as follows: heating to 80°C at a heating rate of 2-5°C / min, holding at that temperature for 12-16 hours, then evacuating the vacuum, then heating to 90-160°C at a heating rate of 2-5°C / min and holding at that temperature for 6-10 hours, and finally cooling naturally to room temperature; more preferably, heating to 80°C at a heating rate of 2-5°C / min, holding at that temperature for 12 hours, then heating to 90°C at a heating rate of 2-5°C / min, evacuating the vacuum and holding at that temperature for 6 hours, and finally cooling naturally to room temperature, thereby obtaining a photosensitive polyimide film.

[0060] Furthermore, the substrate can be a silicon wafer, special glass, metal foil, etc., and more preferably a silicon wafer.

[0061] The present invention has the following beneficial effects: This invention provides a diamine monomer with a special structure. Reaction of this diamine monomer with a tetracarboxylic acid derivative can produce polyamic acid esters. The resulting polyamic acid esters have a narrow molecular weight distribution and a special structure introduced by the diamine monomer in the molecular chain. They not only have good solubility and film-forming properties, but also excellent dielectric properties. They reduce the dielectric constant, dielectric loss and water absorption of polyimide, making them a high-performance resin with wide applications in the electronics and aerospace fields. Detailed Implementation

[0062] The following description illustrates exemplary embodiments of the present invention, including various details to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the invention. Similarly, for clarity and brevity, descriptions of well-known functions, operations, and structures are omitted in the following description.

[0063] Unless otherwise defined, the technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art. While similar or identical methods and materials may be applied in experimental or practical applications, the present invention describes materials and methods hereinafter. In case of conflict, the definitions included herein shall prevail.

[0064] Unless otherwise specified, the raw materials used in the following examples and comparative examples were all purchased commercially.

[0065] Synthesis of the diamine monomer of formula (1-1) in Example 1 In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 21.23 g (0.05 mol) of di(4-hydroxy-3,5-di-tert-butyl)benzane, 21.21 g (0.105 mol) of m-bromonitrobenzene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then refluxed at 120 °C for 12 h. After the reaction was complete, the mixture was cooled, and the reaction solution was poured into five times its mass of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 25.34 g (0.038 mol) of bis(3,5-di-tert-butyl-4-(3-nitrobenzoxy)phenyl)methane with a purity (HPLC) of 98.1% and a yield of 76% based on di(4-hydroxy-3,5-di-tert-butyl)benzane.

[0066] In a 500 mL high-pressure reactor, 200 mL of DMF, 25.34 g (0.038 mol) of bis(3,5-di-tert-butyl-4-(3-nitrophenoxy)phenyl)methane, and 0.855 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to bring the pressure to 0.4 MPa, and the reaction was carried out for 4 hours. Hydrogen gas was then introduced again to bring the pressure to 0.4 MPa, and the reaction was continued for another 4 hours. The pressure remained constant at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into four times its weight of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80 °C to obtain 19.67 (0.032 mol) g of bis(3,5-di-tert-butyl-4-(3-aminophenoxy)phenyl)methane with a purity (HPLC) of 97.9% and a yield of 84.2% based on bis(3,5-di-tert-butyl-4-(3-nitrobenoxy)phenyl)methane. This step can be repeated to obtain more product.

[0067] The NMR data for the diamine monomer (1-1) are as follows: 1 H NMR (500MHZ, DMSO): δ 1.34 (36H, s), 3.41 (4H, s), 3.54 (2H, s), 6.74 (2H, d), 6.83-6.96 (6H, m), 7.04 (2H, d), 7.21 (2H, d).

[0068] Synthesis of the diamine monomer of formula (1-3) in Example 2 In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 21.23 g (0.05 mol) of di(4-hydroxy-3,5-di-tert-butyl)benzylmethane, 22.68 g (0.105 mol) of 3-nitro-5-bromotoluene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then refluxed at 120 °C for 12 h. After the reaction was complete, the mixture was cooled, and the reaction solution was poured into five times its weight of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 25.02 g (0.036 mol) of bis(3,5-di-tert-butyl-4-(3-methyl-5-nitrophenoxy)phenyl)methane with a purity (HPLC) of 97.9% and a yield of 72% based on di(4-hydroxy-3,5-di-tert-butyl)benzylmethane.

[0069] In a 500 mL high-pressure reactor, 200 mL of DMF, 25.02 g (0.036 mol) of bis(3,5-di-tert-butyl-4-(3-methyl-5-nitrophenoxy)phenyl)methane, and 0.85 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to bring the pressure to 0.4 MPa, and the reaction was allowed to proceed for 4 hours. Hydrogen gas was then introduced again to bring the pressure to 0.4 MPa, and the reaction was continued for another 4 hours. The pressure remained constant at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into four times its weight of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80 °C to obtain 17.78 g (0.028 mol) of bis(3,5-di-tert-butyl-4-(3-methyl-5-aminophenoxy)phenyl)methane with a purity (HPLC) of 98.1% and a yield of 77.8% based on bis(3,5-di-tert-butyl-4-(3-methyl-5-nitrobenoxy)phenyl)methane. This step can be repeated to obtain more product.

[0070] The NMR data for the diamine monomers (1-3) are as follows: 1 H NMR (500MHZ, DMSO): δ 1.34 (36H, s), 2.32 (6H, s), 3.41 (4H, s), 3.54 (2H, s), 6.29-6.47 (4H, m), 6.75 (2H, t), 6.88 (4H, d).

[0071] Synthesis of diamine monomers of formula (1-5) in Example 3 In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 21.23 g (0.05 mol) of di(4-hydroxy-3,5-di-tert-butyl)benzane, 27.10 g (0.105 mol) of 1-bromo-3-(tert-butyl)-5-nitrobenzene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then refluxed at 120 °C for 12 h. After the reaction was complete, the mixture was cooled, and the reaction solution was poured into 5.4 times its mass of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 32.72 g (0.042 mol) of bis(3,5-di-tert-butyl-4-(3-(tert-butyl)-5-nitrobenzoxy)phenyl)methane with a purity (HPLC) of 98.3% and a yield of 84% based on di(4-hydroxy-3,5-di-tert-butyl)benzane.

[0072] In a 500 mL high-pressure reactor, 200 mL of DMF, 32.72 g (0.042 mol) of bis(3,5-di-tert-butyl-4-(3-(tert-butyl)-5-nitrophenoxy)phenyl)methane, and 0.85 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to reach a pressure of 0.4 MPa, and the reaction was carried out for 4 h. Hydrogen gas was then introduced again to reach a pressure of 0.4 MPa, and the reaction was continued for another 4 h. The pressure remained constant at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into 4.3 times its mass of deionized water to precipitate a solid. The solid was then obtained by filtration. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80 °C to obtain 23.01 g (0.032 mol) of bis(3,5-di-tert-butyl-4-(3-(tert-butyl)-5-aminophenoxy)phenyl)methane with a purity (HPLC) of 97.5% and a yield of 76.2% based on bis(3,5-di-tert-butyl-4-(3-(tert-butyl)-5-nitrophenoxy)phenyl)methane. This step can be repeated to obtain more product.

[0073] The NMR data for the diamine monomers (1-5) are as follows: 1 H NMR (500MHZ, DMSO): δ 1.19-1.39 (54H, m), 3.41 (4H, s), 3.54 (2H, s), 6.28-6.41 (4H, m), 6.75 (2H, d), 6.88 (4H, d).

[0074] Synthesis of diamine monomers of formula (1-6) in Example 4 In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 21.23 g (0.05 mol) of di(4-hydroxy-3,5-di-tert-butyl)benzene, 28.35 g (0.105 mol) of 4-bromo-2-nitro-1-(trifluoromethyl)benzene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then refluxed at 120 °C for 12 h. After the reaction was complete, the mixture was cooled, and the reaction solution was poured into five times its mass of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 32.11 g (0.04 mol) of bis(3,5-di-tert-butyl-4-(3-nitro-4-(trifluoromethyl)phenoxy)phenyl)methane with a purity (HPLC) of 98.15% and a yield of 80% based on di(4-hydroxy-3,5-di-tert-butyl)benzene.

[0075] In a 500 mL high-pressure reactor, 200 mL of DMF, 32.11 g (0.04 mol) of bis(3,5-di-tert-butyl-4-(3-nitro-4-(trifluoromethyl)phenoxy)phenyl)methane, and 0.85 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to reach a pressure of 0.4 MPa, and the reaction was carried out for 4 hours. Hydrogen gas was then introduced again to reach a pressure of 0.4 MPa, and the reaction was continued for another 4 hours. The pressure remained constant at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into four times its weight of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80 °C to obtain 23.03 g (0.031 mol) of bis(3,5-di-tert-butyl-4-(3-amino-4-(trifluoromethyl)phenoxy)phenyl)methane with a purity (HPLC) of 98.9% and a yield of 77.5% based on bis(3,5-di-tert-butyl-4-(3-nitro-4-(trifluoromethyl)phenoxy)phenyl)methane. This step can be repeated to obtain more product.

[0076] The NMR data for the diamine monomers (1-6) are as follows: 1 H NMR (500MHZ, DMSO): δ1.34 (36H, s), 3.41 (4H, s), 3.54 (2H, s), 6.37 (2H, d), 6.83-7.02 (8H, m).

[0077] Synthesis of the diamine monomer of formula (1-7) in Example 5 In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 21.23 g (0.05 mol) of di(4-hydroxy-3,5-di-tert-butyl)benzyl methane, 22.68 g (0.105 mol) of 3-nitrobenzyl bromide, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then refluxed at 120 °C for 12 h. After the reaction was complete, the mixture was cooled, and the reaction solution was poured into five times its weight of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 29.88 g (0.043 mol) of bis(3,5-di-tert-butyl-4-((3-nitrobenzyl)oxy)phenyl)methane with a purity (HPLC) of 97.9% and a yield of 86% based on di(4-hydroxy-3,5-di-tert-butyl)benzyl methane.

[0078] In a 500 mL high-pressure reactor, 200 mL of DMF, 29.88 g (0.043 mol) of bis(3,5-di-tert-butyl-4-((3-nitrobenzyl)oxy)phenyl)methane, and 0.85 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to bring the pressure to 0.4 MPa, and the reaction was carried out for 4 h. Hydrogen gas was then introduced again to bring the pressure to 0.4 MPa, and the reaction was continued for another 4 h. The pressure remained constant at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into 4.3 times its mass of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet product was purified with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80°C to obtain 20.95 g (0.033 mol) of bis(3,5-di-tert-butyl-4-((3-aminobenzyl)oxy)phenyl)methane with a purity (HPLC) of 97.9% and a yield of 76.74% based on bis(3,5-di-tert-butyl-4-((3-nitrobenzyl)oxy)phenyl)methane. This step can be repeated to obtain more product.

[0079] The NMR data for the diamine monomers (1-7) are as follows: 1 H NMR (500MHZ, DMSO): δ 1.31 (36H, s), 3.41 (4H, s), 3.50 (2H, s), 5.05 (4H, s), 6.72-6.95 (8H, m), 7.07-7.21 (4H, m).

[0080] Synthetic Example 6: Synthesis of diamine monomers of formulas (1-9) In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 22.64 g (0.05 mol) of 4,4'-isopropylidene di[2,6-di-tert-butylphenol], 22.22 g (0.11 mol) of m-bromonitrobenzene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then heated to 120 °C under weak reflux for 12 h. After the reaction was completed, the mixture was cooled, and the reaction solution was poured into 6 times its mass of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 27.10 g (0.039 mol) of 4,4'-isopropylidene di[2,6-di-tert-butyl-2-(3-nitrophenoxy)benzene] with a purity of 96.9% by HPLC and a yield of 78% based on 4,4'-isopropylidene di[2,6-di-tert-butylphenol].

[0081] In a 500 mL high-pressure reactor, 200 mL of DMF, 27.10 g (0.039 mol) of 4,4'-isopropylidene di[2,6-di-tert-butyl-2-(3-nitrobenzyloxy)benzene], and 0.91 g of palladium on carbon (10% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to reach a pressure of 0.4 MPa, and the reaction was carried out for 4 h. Hydrogen gas was then introduced again to reach a pressure of 0.4 MPa, and the reaction was continued for another 4 h. The pressure remained stable at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into 4.5 times its mass of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80°C to obtain 21.59 g (0.034 mol) of 4,4'-isopropylidene di[2,6-di-tert-butyl-2-(3-aminophenoxy)benzene] with a purity (HPLC) of 98.4% and a yield of 87.2% for 4,4'-isopropylidene di[2,6-di-tert-butyl-2-(3-nitrobenzenoxy)benzene]. This step can be repeated to obtain more products.

[0082] The NMR data for the diamine monomers (1-9) are as follows: 1 H NMR: δ 1.34 (36H, s), 1.50 (6H, s), 3.41 (4H, s), 6.74 (2H, d), 6.83-6.96 (6H, m), 7.04 (2H, d), 7.21 (2H, d). Synthesis Example 7: Synthesis of the diamine monomer of formula (1-11) In a 500 mL three-necked flask, 250 mL of N,N-dimethylacetamide was added, followed by 23.43 g (0.05 mol) of di(3,5-di-tert-butyl-4-hydroxyphenyl)acetic acid, 24.2 g (0.11 mol) of 4-bromo-1-fluoro-2-nitrobenzene, and 5.6 g (0.14 mol) of sodium hydroxide. The mixture was stirred until completely dissolved, and then heated to 120 °C under weak reflux for 12 h. After the reaction was completed, the mixture was cooled, and the reaction solution was poured into 6 times its weight of deionized water, precipitating a solid. The solid was dried under vacuum at 80 °C to obtain 25.06 g (0.035 mol) of di[3,5-bis(tert-butyl)-4-(4-fluoro-3-nitrophenoxy)phenyl]acetic acid with a purity of 96.9% by HPLC and a yield of 70% based on di(3,5-di-tert-butyl-4-hydroxyphenyl)acetic acid.

[0083] In a 500 mL high-pressure reactor, 200 mL of DMF, 25.06 g (0.035 mol) of di[3,5-bis(tert-butyl)-4-(4-fluoro-3-nitrophenoxy)phenyl]acetic acid, and 0.94 g of palladium on carbon (5% palladium loading) were added, and the temperature was raised to 80 °C. Hydrogen gas was introduced into the reactor to reach a pressure of 0.4 MPa, and the reaction was carried out for 4 h. Hydrogen gas was then introduced again to reach a pressure of 0.4 MPa, and the reaction was continued for another 4 h. The pressure remained stable at 0.2 MPa. After the reaction was completed, hydrogen gas was released, and the reaction solution was poured into four times its weight of deionized water to precipitate a solid. The solid was then filtered to obtain a wet product. The wet sample was washed with a mixture of methanol and water (methanol:water volume ratio 1:3), filtered, and dried under vacuum at 80°C to obtain 21.26 g (0.031 mol) of di[3,5-bis(tert-butyl)-4-(4-fluoro-3-aminophenoxy)phenyl]acetic acid with a purity (HPLC) of 98.1% and a yield of 88.6% based on di[3,5-bis(tert-butyl)-4-(4-fluoro-3-nitrophenoxy)phenyl]acetic acid. This step can be repeated to obtain more products.

[0084] The NMR data for the diamine monomer (1-11) are as follows: 1 H NMR (500MHZ, DMSO): δ 1.34 (36H, s), 3.41 (4H, s), 5.55 (1H, s), 6.46 (2H, m), 6.85 (4H, d), 7.05 (2H, d), 7.20 (2H, d), 10.69 (1H, s).

[0085] Example 1 Under a dry nitrogen stream, 39.45 g (0.065 mol) of the diamine monomer of formula (1-1) obtained in Synthesis Example 1, 5.53 g (0.03 mol) of 4,4'-diaminobiphenyl, and 1.09 g (0.01 mol) of 3-aminophenol were dissolved in 200 g of N-methylpyrrolidone (NMP). 31.03 g (0.1 mol) of 4,4'-oxophthalic anhydride (ODPA) was added, and the mixture was stirred at 40 °C for 2 hours. Then, 2.063 g (0.01 mol) of dicyclohexylcarbodiimide (DCC) was added dropwise over 10 minutes, followed by the addition of a solution obtained by diluting 7.71 g (0.065 mol) of N,N-dimethylformamide dimethyl acetal (DFA) with 15 g of NMP. After the addition, the mixture was stirred at 80 °C for 6 hours. After stirring, the solution was added to 2 L of water, and the polymer solid precipitate was collected by filtration. Then, the polymer solid was washed three times with 2L of water and dried in a vacuum dryer at 50°C for 72 hours to obtain polyamic acid ester (PAE-1).

[0086] 10 g of polyamic acid ester (PAE-1), 2 g of photosensitizer diazonoquinone compound (DNQ), and 0.01 g of coupling agent KBM-1403 (manufacturer Shin-Etsu Chemical) were dissolved in 87.99 g of γ-butyrolactone (GBL) to obtain a positive photosensitive resin composition PSPI-1 with a viscosity of 7.3 mPa·s.

[0087] The obtained positive photosensitive resin composition was coated onto the surface of a silicon wafer by spin coating. The silicon wafer was placed on a hot plate and pre-cured at 80°C for 30 seconds, then transferred to a high-temperature oven and cured at 200°C for 30 minutes. Hydrofluoric acid was then used to remove the film from the silicon wafer to obtain a photosensitive polyimide film (PI-1).

[0088] Example 2 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-3) obtained in Synthesis Example 2. The resulting positive photosensitive resin composition is designated as PSPI-2, and the resulting photosensitive polyimide film is designated as PI-2.

[0089] Example 3 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-5) obtained in Synthesis Example 3. The resulting positive photosensitive resin composition is designated as PSPI-3, and the photosensitive polyimide film is designated as PI-3.

[0090] Example 4 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-6) obtained in Synthesis Example 4. The resulting positive photosensitive resin composition is designated as PSPI-4, and the photosensitive polyimide film is designated as PI-4.

[0091] Example 5 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-7) obtained in Synthesis Example 5. The resulting positive photosensitive resin composition is designated as PSPI-5, and the photosensitive polyimide film is designated as PI-5.

[0092] Example 6 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-9) obtained in Synthesis Example 6. The resulting positive photosensitive resin composition is designated as PSPI-6, and the photosensitive polyimide film is designated as PI-6.

[0093] Example 7 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of the diamine monomer of formula (1-11) obtained in Synthesis Example 7. The resulting positive photosensitive resin composition is designated as PSPI-7, and the photosensitive polyimide film is designated as PI-7.

[0094] Example 8 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with 0.0325 mol of the diamine monomer of formula (1-1) obtained in Synthesis Example 1 and 0.0325 mol of the diamine monomer of formula (1-5) obtained in Synthesis Example 3. The resulting positive photosensitive resin composition is designated as PSPI-8, and the photosensitive polyimide film is designated as PI-8.

[0095] Example 9 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with 0.0325 mol of the diamine monomer of formula (1-3) prepared in Synthesis Example 2 and 0.0325 mol of the diamine monomer of formula (1-5) prepared in Synthesis Example 3. The resulting positive photosensitive resin composition is designated as PSPI-9, and the photosensitive polyimide film is designated as PI-9.

[0096] Example 10 The method is the same as in Example 9, except that 0.03 mol of 4,4'-diaminobiphenyl is replaced with 0.015 mol of 4,4'-diaminobiphenyl and 0.015 mol of p-phenylenediamine, and 0.1 mol of 4,4'-oxydiphthalic anhydride (ODPA) is replaced with 0.05 mol of 4,4'-oxydiphthalic anhydride (ODPA) and 0.05 mol of 3,3,4',4'-biphenyltetracarboxylic acid dianhydride (BPDA). The resulting positive photosensitive resin composition is designated PSPI-10, and the photosensitive polyimide film is designated PI-10.

[0097] Example 11 Under a dry nitrogen stream, 20.64 g (0.0325 mol) of the diamine monomer of formula (1-3) obtained in Synthesis Example 2, 23.37 g (0.0325 mol) of the diamine monomer of formula (1-5) obtained in Synthesis Example 3, 1.62 g (0.015 mol) of p-phenylenediamine, 2.765 g (0.015 mol) of 4,4'-diaminobiphenyl, 0.46 g (0.005 mol) of aniline, and 0.54 g (0.005 mol) of 3-aminophenol were dissolved in 200 g of N-methylpyrrolidone (NMP). 15.51 g (0.05 mol) of 4,4'-oxydiphthalic anhydride (ODPA) and 14.711 g (0.05 mol) of 3,3,4',4'-biphenyltetracarboxylic acid dianhydride (BPDA) were added to the solution, and the mixture was stirred at 40 °C for 2 hours. Next, 2.063 g (0.01 mol) of dicyclohexylcarbodiimide (DCC) was added dropwise over 10 minutes, followed by the addition of a solution obtained by diluting 7.71 g (0.065 mol) of N,N-dimethylformamide dimethyl acetal (DFA) with 5 g of NMP. After the addition, the mixture was stirred at 80 °C for 6 hours. After stirring, the solution was added to 2 L of water, and the polymer solid precipitate was collected by filtration. The precipitate was then washed three times with 2 L of water, and the collected polymer solid was dried in a vacuum dryer at 50 °C for 72 hours to obtain polyamic acid ester (PAE-11).

[0098] 10 g of polyamic acid ester (PAE-11), 2 g of photosensitizer diazonaphthoquinone compound (DNQ), and 0.01 g of coupling agent KBM-1403 (manufacturer Shin-Etsu Chemical) were dissolved in 87.99 g of γ-butyrolactone (GBL) to obtain a positive photosensitive resin composition PSPI-11 with a viscosity of 9.37 mPa·s.

[0099] The obtained positive photosensitive resin composition was coated onto the surface of a silicon wafer by spin coating. The silicon wafer was placed on a hot plate and pre-cured at 80°C for 30 seconds, then transferred to a high-temperature oven and cured at 200°C for 30 minutes. Hydrofluoric acid was then used to remove the film from the silicon wafer to obtain a photosensitive polyimide film (PI-11).

[0100] Example 12 Under a dry nitrogen stream, 19.72 g (0.0325 mol) of the diamine monomer of formula (1-1) obtained in Synthesis Example 1, 23.37 g (0.0325 mol) of the diamine monomer of formula (1-5) obtained in Synthesis Example 3, and 6.45 g (0.035 mol) of 4,4'-diaminobiphenyl were dissolved in 200 g of N-methylpyrrolidone (NMP). 31.02 g (0.1 mol) of 4,4'-oxophthalic anhydride (ODPA) was added, and the mixture was stirred at 40 °C for 2 hours. Then, 2.063 g (0.01 mol) of dicyclohexylcarbodiimide (DCC) was added dropwise over 10 minutes, and the mixture was further stirred at 80 °C for 6 hours after the addition of 7.71 g (0.065 mol) of N,N-dimethylformamide dimethyl acetal (DFA) diluted with 5 g of NMP. After stirring, the solution was added to 2L of water, and the polymer solid precipitate was collected by filtration. Then, it was washed three times with 2L of water, and the collected polymer solid was dried in a vacuum dryer at 50°C for 72 hours to obtain polyamic acid ester (PAE-12).

[0101] 10 g of polyamic acid ester (PAE-12), 2 g of photosensitizer diazonaphthoquinone compound (DNQ), and 0.01 g of coupling agent KBM-1403 (manufacturer Shin-Etsu Chemical) were dissolved in 87.99 g of γ-butyrolactone (GBL) to obtain a positive photosensitive resin composition PSPI-12 with a viscosity of 20.37 mPa·s.

[0102] The obtained positive photosensitive resin composition was coated onto the surface of a silicon wafer by spin coating. The silicon wafer was placed on a hot plate and pre-cured at 80°C for 30 seconds, then transferred to a high-temperature oven and cured at 200°C for 30 minutes. Hydrofluoric acid was then used to remove the film from the silicon wafer to obtain a photosensitive polyimide film (PI-12).

[0103] Example 13 The method is the same as in Example 1, except that the molar amount of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 (0.065 mol) is replaced with 0.03 mol, and the molar amount of 4,4'-diaminobiphenyl (0.03 mol) is replaced with 0.065 mol. The resulting positive photosensitive resin composition is designated PSPI-13, and the photosensitive polyimide film is designated PI-13.

[0104] Example 14 The method is the same as in Example 1, except that the molar amount of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 (0.065 mol) is replaced with 0.05 mol, and the molar amount of 4,4'-diaminobiphenyl (0.03 mol) is replaced with 0.045 mol. The resulting positive photosensitive resin composition is designated PSPI-14, and the photosensitive polyimide film is designated PI-14.

[0105] Example 15 The method is the same as in Example 1, except that the molar amount of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 (0.065 mol) is replaced with 0.085 mol, and the molar amount of 4,4'-diaminobiphenyl (0.03 mol) is replaced with 0.010 mol. The resulting positive photosensitive resin composition is designated as PSPI-15, and the photosensitive polyimide film is designated as PI-15.

[0106] Comparative Example 1 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of 2,2′-bis[3-(3-aminobenzamide)-4-hydroxyphenyl]hexafluoropropane (HFHA). The resulting positive photosensitive resin composition is designated PSPI-16, and the photosensitive polyimide film is designated PI-16.

[0107] Comparative Example 2 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (HFBAPP). The resulting positive photosensitive resin composition is designated PSPI-17, and the photosensitive polyimide film is designated PI-17.

[0108] Comparative Example 3 The method is the same as in Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 is replaced with an equimolar amount of 4,4'-bis(4-aminophenoxy)biphenyl. The resulting positive photosensitive resin composition is designated as PSPI-18, and the photosensitive polyimide film is designated as PI-18.

[0109] Comparative Example 4 Under nitrogen protection, 2 mL of HCl and 20 mL of H2O were added to a 500 mL three-necked flask equipped with a stirrer and a thermometer. 10.6 g of benzaldehyde (0.1 mol) and 38.9 g of 2,6-diisopropylaniline (0.22 mol) were slowly added with stirring. After mixing, the mixture was slowly heated to 60 °C and reacted for 8 h. The resulting solution was poured into deionized water, filtered, and repeatedly washed with deionized water until neutral. After drying, bis(4-amino-3,5-diisopropylphenyl)-1-phenylmethane monomer was prepared.

[0110] Polyamic acid ester, positive photosensitive resin composition, and photosensitive polyimide film were prepared according to the method of Example 1, except that 0.065 mol of the diamine monomer of formula (1-1) prepared in Synthesis Example 1 was replaced with an equimolar amount of the bis(4-amino-3,5-diisopropylphenyl)-1-phenylmethane prepared above. The resulting positive photosensitive resin composition is designated PSPI-19, and the photosensitive polyimide film is designated PI-19.

[0111] Performance testing The properties of the polyaminate (PAE), positive photosensitive resin composition (PSPI), and photosensitive polyimide film (PI) prepared in the above examples and comparative examples were tested, as follows: 1. Viscosity test The viscosity of the positive photosensitive resin compositions prepared in each example and comparative example was tested using a DV2TLV cone-plate viscometer (Type E) manufactured by Brookfield, USA. The rotors were: CPA-40Z rotor (0.5 mL sample volume, test range 0–1022 cp); and CPA-41Z rotor (2.0 mL sample volume, test range 0–3837 cp). The temperature was controlled at 25 ± 0.1 °C.

[0112] 2. Molecular weight test The molecular weight and molecular weight distribution of the polyamic acid ester powders prepared in each example and comparative example were determined using GPC under the following conditions: Instrument: Waters 1525; Detector: Waters 2414 differential detector; Chromatographic column: Two Agilent PL gel MIXED-C 5um (300 x 7.8 mm) columns in series; Mobile phase: DMF + 70mM sodium nitrate; Flow rate: 1 ml / min; Temperature: 35℃; Standard: PMMA or PS; The molecular weight distribution of polyimide esters has a significant impact on the properties of polyimide films. The polydispersity index (PDI) is commonly used to measure molecular weight distribution. PDI The higher the value, the wider the molecular weight distribution. PDI = Mw / Mn.

[0113] 3. Solubility test Using γ-butyrolactone (GBL), NMP (N-methylpyrrolidone), DMAc (dimethylacetamide), DMF (N,N-dimethylformamide), and DMSO (dimethyl sulfoxide) as solvents, the solubility of each polyamide ester powder in the solvents was tested according to the gravimetric method (refer to GB / T 5750.4-2021). Specifically, 1 mL of each solvent was accurately weighed, and then the polyamide ester powder prepared in each example and comparative example was gradually added to the solvent. The maximum mass of polyamide ester that could be dissolved in the solvent was recorded, and the maximum concentration of the polyamide ester in the solvent was calculated. The solubility of the polyamide ester was evaluated according to the following standards: 4. Dielectric properties, contact angle, and water absorption rate testing of polyimide (PI) film. Instrument for testing dielectric constant: ZJD-A dielectric constant tester; test conditions: test frequency: 50 kHz ~ 100 MHz; temperature: 23 ± 2 ℃; humidity: < 50% RH.

[0114] Dielectric loss was tested using a Keysight E4990A impedance analyzer. Test conditions: frequency: 50 kHz ~ 100 MHz; temperature: 23 ± 2 ℃; humidity: < 50% RH.

[0115] Contact angle testing instrument: DSA 25 fully automatic optical contact angle measuring instrument; testing conditions: temperature: 23±2℃; humidity: <50%RH; the workbench should be dust-free and vibration-free; the sample surface should be thoroughly cleaned.

[0116] Instrument used for testing water absorption rate: Cobb water absorption meter; test conditions: temperature 23±1℃; humidity: 50±2%RH; sample pretreatment time: >4h.

[0117] 5. Test Results 5.1. The viscosity, molecular weight of the polyamic acid ester, and PDI of the positive photosensitive resin compositions of each embodiment and comparative example are shown in Table 1 below: Table 1 As can be seen from Table 1, the molecular weight of the polyamide esters obtained in each embodiment of the present invention is higher than that in each comparative example, indicating that the novel diamine of the present invention makes it easier to obtain a weight-average molecular weight (M). wThe polyamic acid esters with higher molecular weight distributions are shown in the comparison of Examples 1-15. The polyamic acid esters of Examples 8-11 have a narrower molecular weight distribution, indicating that a polyamic acid ester with a narrower molecular weight distribution can be obtained by combining diamine and tetracarboxylic acid derivatives.

[0118] 5.2. The solubility properties of the polyaminates in different solvents for each example and comparative example are shown in Table 2 below.

[0119] Table 2 As shown in Table 2, except for Example 13, the solubility of the polyamic acid esters in all examples is better than that in the comparative examples, indicating that the use of the novel diamine with the special structure of the present invention improves the solubility of the polyamic acid esters. Example 13 has lower solubility due to a lower content of the novel diamine. A comparison of Examples 1-7 and Examples 8-9 shows that using a combination of two novel diamines of the present invention can improve the solubility of the polyamic acid esters. A comparison of Examples 8 and 12 shows that the addition of a monoamine can improve the solubility of the polyamic acid esters. A comparison of Examples 1, 13, 14, and 15 shows that the solubility of the polyamic acid continuously increases with the increase of the content of the novel diamine of the present invention.

[0120] 5.3 The dielectric properties, contact angles, and water absorption rates of the polyimide films (PI) in each embodiment and comparative example are shown in Table 3 below.

[0121] Table 3 As can be seen from Table 3 by comparing Examples 1-7 and Comparative Examples 1-4, the polyimide film with the specific structure of the present invention has a lower dielectric constant and dielectric loss, and a lower water absorption rate. Comparing Examples 1-9, it can be seen that Example 9, which uses a mixture of diamines with the special structure of the present invention, is the best. Comparing Examples 9, 10, and 11, it can be seen that the component combination in Example 10 is optimal.

[0122] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. A diamine monomer with a tert-butyl side chain, characterized in that: It has the structure shown in equation (1): In formula (1), A is hydrogen, -COOH, dimethyl, oxygen, phenyl or ethyl; R1 is hydrogen, methyl, tert-butyl, -F, -CF3 or -OH; R2 is an alkylene group with 0 to 7 carbon atoms.

2. The diamine monomer according to claim 1, characterized in that: It is any one of the compounds shown in formulas (1-1) to (1-12): 。 3. A method for preparing a diamine monomer with a tert-butyl side chain as described in claim 1, characterized in that: Includes the following steps: (1-1) The compound with the structure shown in formula (2), the compound with the structure shown in formula (3), organic solvent I and a basic substance are mixed and reacted to obtain the intermediate product with the structure shown in formula (4); (1-2) Under a hydrogen atmosphere, the intermediate product with the structure shown in formula (4), organic solvent II and catalyst are mixed and reacted to obtain a diamine monomer with tert-butyl side chain.

4. The preparation method according to claim 3, characterized in that: Compounds with the structure shown in formula (3) include di(4-hydroxy-3,5-di-tert-butyl)benzane, 4,4'-isopropylidene di[2,6-di-tert-butylphenol] or 2,2-bis(3,5-di-tert-butyl-4-hydroxyphenyl)acetic acid; Preferably, in step (1-1), the molar ratio of the compound with the structure shown in formula (3) to the compound with the structure shown in formula (2) is 1:(2~2.3). Preferably, in step (1-1), the alkaline substance is sodium hydroxide, potassium hydroxide, or sodium hydride; Preferably, in step (1-1), the molar ratio of the compound with the structure shown in formula (3) to the alkaline substance is 1:(2.6~3.0). Preferably, in step (1-1), the reaction temperature is 100–120°C; Preferably, in steps (1-2), the catalyst is a noble metal catalyst; Preferably, in step (1-2), the pressure of hydrogen is 0.2 to 0.4 MPa; Preferably, in step (1-2), the reaction temperature is 70-90℃.

5. A polyamic acid ester, characterized in that: it is composed of... The polyamic acid is obtained by reacting at least one amine compound and at least one tetracarboxylic acid derivative, and then reacting the polyamic acid with an esterification agent; the amine compound includes a diamine, the diamine includes diamine A, and diamine A is at least one of the diamine monomers with a tert-butyl side chain as described in claim 1 or 2.

6. The polyamic acid ester according to claim 5, characterized in that: The diamine further includes diamine B, wherein diamine B is p-phenylenediamine, 3,5-diaminobenzoic acid, 1,4-bis(4-aminophenoxy)benzene, 1,5-naphthyldiamine, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 3,3'-dichlorobenzidine, 4,4'-bis(4-aminophenoxy)biphenyl, or diaminodiphenyl... At least one of the following: phenylmethane, 4,4'-diaminodiphenyl ether, 2,2-diaminodiphenylpropane, 4,4'-diaminodiphenyl sulfone, diaminobenzophenone, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)diphenyl sulfone, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, and 1,3-bis(3-aminopropyl)tetramethyldisiloxane; Preferably, the amine compound further includes a monoamine, wherein the monoamine is at least one selected from aniline, 3-aminophenol, 4-ethynylaniline, phenylethynyltrifluoromethylaniline, 2-phenylethynylaniline, 4-aminobenzoic acid, 4-aminophenylmaleimide, 3-aminopropyltriethoxysilane, 4-(trifluoromethyl)aniline, 2-aminothiazole, and 4-amino-2,2,6,6-tetramethylpiperidine; Preferably, the tetracarboxylic acid derivative is at least one of tetracarboxylic dianhydride, tetracarboxylic monohydric anhydride, tetracarboxylic acid, dialkyl dicarboxylic acid ester, and dialkyl dicarboxylic acid acyl chloride ester.

7. The polyamic acid ester according to claim 5 or 6, characterized in that: The content of diamine in amine compounds is 90-100 mol%; Preferably, the content of diamine A in the total diamine is 30-90 mol%, more preferably 50-90 mol%, and even more preferably 60-70 mol%. Preferably, the molar ratio of the tetracarboxylic acid derivative to the total diamine is 1:0.8 to 1:1; Preferably, the weight-average molecular weight of the polyamide ester is 10,000 to 50,000.

8. A photosensitive resin composition, characterized in that: The polyamide ester included in any one of claims 5-7.

9. The photosensitive resin composition according to claim 8, characterized in that: It also includes at least one of coupling agents, photosensitizers, and solvents; Preferably, the mass ratio of polyamic acid ester to coupling agent is 100:0.1~20; Preferably, the mass ratio of polyamic acid ester to photosensitizer is 1:0.05~1; The amount of solvent used should ensure that the concentration of polyamic acid ester is 5~13wt%.

10. A polyimide film, characterized in that: Made from the photosensitive resin composition of claim 8 or 9.

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