A hydrophobic thermoplastic polyimide resin and preparation method thereof

Abstract

The present invention discloses a hydrophobic thermoplastic polyimide resin and a preparation method thereof, and the preparation method comprises the following steps: S1, mixing a dianhydride monomer with a polar solvent, adding a diamine monomer, stirring, and obtaining a polyamic acid solution; S2, adding an organic base and a dehydrating agent to the polyamic acid solution, heating, stirring, adding the reaction solution to an alcohol solvent to precipitate a precipitate, collecting the precipitate, washing, and drying to obtain a hydrophobic thermoplastic polyimide resin. By introducing a fluorinated alkyl group, the hydrophobicity and various properties of the thermoplastic polyimide resin are effectively improved; relative to the existing method of coating a hydrophobic coating on the surface of polyimide or constructing a micro-nano structure, the technical solution of the present invention avoids the reduction of structural strength caused by doping, and while improving the hydrophobicity of the polyimide, a longer hydrophobic period can be maintained. By introducing a long-chain fluorinated alkane and introducing a large number of fluorine atoms, the water contact angle can reach more than 120°, showing excellent hydrophobicity.

Description

Technical Field

[0001] The invention relates to the technical field of polyimide materials, and in particular to a hydrophobic thermoplastic polyimide resin and a preparation method thereof. Background Art

[0002] Polyimide has high thermal stability, good mechanical properties and excellent chemical properties, and is widely used in the fields of microelectronics and aerospace. At the same time, polyimide can be used as a dielectric protection layer and passivation layer, and is used in the packaging and manufacturing of important equipment microelectronic devices.

[0003] Although polyimide has a low surface energy, the currently known polyimide can still absorb a certain amount of water, causing metal corrosion, package cracking, film-metal adhesion failure, and dielectric performance degradation. Therefore, it is necessary to hydrophobicize the polyimide film.

[0004] Hydrophobic modification usually involves coating the polyimide surface with a hydrophobic coating or constructing a micro-nano structure. The hydrophobic coating is mainly applied by coating fluorine-containing compounds such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and fluorocarbon coatings. Although the surface hydrophobicity is greatly improved after coating with fluorine-containing compounds, the binding force between the fluorine-containing material and the polyimide interface is weak due to the two-sided nature of the fluorine-containing material, which can easily cause the fluorine coating to fall off. The use of chemical methods to construct micro-nano structures can significantly improve the hydrophobicity and even achieve super-hydrophobicity. However, the nanoparticles are closely connected to the polyimide by the connecting layer, which is a physical bond and cannot form a strong binding force with the polyimide. During use, the particles will still fall off and the hydrophobic period is short. Therefore, how to improve the hydrophobicity of the polyimide membrane surface while maintaining a longer hydrophobic period of the hydrophobic layer is a problem that needs to be solved urgently. Summary of the invention

[0005] In order to overcome the above-mentioned shortcomings, one of the purposes of the present invention is to provide a hydrophobic thermoplastic polyimide resin, which does not require coating a hydrophobic coating on the surface of the polyimide or constructing a micro-nano structure, thereby avoiding the reduction in structural strength caused by doping, and can maintain a longer hydrophobic period while improving the hydrophobicity of the polyimide.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is: a hydrophobic thermoplastic polyimide resin, the hydrophobic thermoplastic polyimide resin has the following structural formula:

[0007]

[0008] Among them, n≥5;

[0009] Ar is selected from aromatic structures;

[0010] R 1and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0011] Preferably, n≥50.

[0012] More preferably, n≥100.

[0013] Furthermore, R 1 and R 2 For R f or -COOR f Any one of R f It is a fluorinated alkyl chain.

[0014] Furthermore, R f -(CH2) x R y , where x ≥ 0, R y It is a perfluoroalkyl chain.

[0015] Furthermore, R f Any of the following structures:

[0016]

[0017] Among them, m≥0.

[0018] Further, Ar is any one of the following structures:

[0019] .

[0020] Furthermore, the raw materials for preparing the hydrophobic thermoplastic polyimide resin include dianhydride monomers and diamine monomers, and the dianhydride monomer is any one of the following structures:

[0021]

[0022]

[0023] .

[0024] Further, the structural formula of the diamine monomer is:

[0025]

[0026] Among them, R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0027] Further, the diamine monomer is any one of the following structures:

[0028]

[0029] Where R f It is a fluorinated alkyl chain.

[0030] Further, the synthetic route of the diamine monomer is:

[0031]

[0032] Among them, R f is a fluorinated alkyl chain;

[0033] R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0034] Furthermore, when the functional group A and / or B in the raw material 1 is an F atom, the specific synthesis steps of the diamine monomer are:

[0035] Step 1: Raw materials 1, R f -OH and a base are added to a polar solvent, heated and stirred, and after the reaction is completed, the reaction solution is poured into water and filtered to obtain intermediate 1;

[0036] Step 2: adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0037] Furthermore, when the functional group A and / or B in the raw material 1 is an F atom, the specific synthesis steps of the diamine monomer are:

[0038] Step 1: Raw materials 1, R f -OH and a base are added to a polar solvent, and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the reaction solution is poured into water, filtered to obtain a solid, and then washed and dried to obtain intermediate 1;

[0039] Step 2: Add intermediate 1, p-aminophenol and base to a polar solvent, stir at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pour the reaction solution into water, filter to obtain a solid, and obtain a diamine monomer after washing and drying.

[0040] Further, when the functional group A and / or B in the raw material 1 is a carboxyl group, the synthesis steps are:

[0041] Step (1), raw material 1, R f-OH and an acid catalyst are added to toluene, and the temperature is raised to reflux and stirred for reaction. After the reaction is completed, recrystallization is performed to obtain intermediate 1;

[0042] Step (2), adding intermediate 1, p-aminophenol and base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0043] Furthermore, when the functional group A and / or B in the raw material 1 is a carboxyl group, the synthesis steps are:

[0044] Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, and the mixture is refluxed and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the toluene is removed by rotary evaporation, and the intermediate 1 is obtained by recrystallization;

[0045] Step (2), adding intermediate 1, p-aminophenol and a base to a polar solvent, stirring at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pouring the reaction solution into water, filtering to obtain a solid, and washing and drying to obtain a diamine monomer.

[0046] Furthermore, when the functional groups A and B in the raw material 1 are F atom and carboxyl group respectively, the synthesis steps are:

[0047] Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, the temperature is raised to reflux and stirred for reaction, and after the reaction is completed, recrystallization is performed to obtain the product;

[0048] Step 1, adding the product obtained in step (1), Rf-OH and a base to a polar solvent, heating and stirring to react, after the reaction is completed, pouring the reaction solution into water, filtering to obtain an intermediate 1;

[0049] Step 2: adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0050] Furthermore, when the functional groups A and B in the raw material 1 are F atom and carboxyl group respectively, the synthesis steps are:

[0051] Step (1), raw material 1, R f -OH and acid catalyst are added to toluene, and refluxed and stirred at 80°C~150°C for 2~24h. After the reaction is completed, the toluene is removed by rotary evaporation, and the product is obtained by recrystallization;

[0052] Step 1: The product obtained in step (1), R f-OH and a base are added to a polar solvent, and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the reaction solution is poured into water, filtered to obtain a solid, and then washed and dried to obtain intermediate 1;

[0053] Step 2: Add intermediate 1, p-aminophenol and base to a polar solvent, stir at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pour the reaction solution into water, filter to obtain a solid, and obtain a diamine monomer after washing and drying.

[0054] Furthermore, in step 1 and / or step (1), raw material 1 and R f The molar ratio of -OH is 1:1~5.

[0055] Furthermore, in step 1 and / or step 2 and / or step (2), the base is at least one of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium tert-butoxide, potassium tert-butoxide, and sodium hydride.

[0056] Furthermore, in step 1, the molar ratio of raw material 1 to alkali is 1:1-5.

[0057] Furthermore, in step 2 and / or step (2), the molar ratio of intermediate 1 to base is 1:1-5.

[0058] Furthermore, in step 2 and / or step (2), the molar ratio of intermediate 1 to p-aminophenol is 1:1-5.

[0059] Furthermore, in step 1 and / or step 2 and / or step (2), the polar solvent is at least one of DMF, DMAc and NMP.

[0060] Furthermore, in step (1), the acid catalyst is at least one of sulfuric acid, methanesulfonic acid and p-toluenesulfonic acid.

[0061] Furthermore, in step (1), the molar ratio of raw material 1 to acid catalyst is 1:0.01-0.25.

[0062] Furthermore, when the functional groups A and B in the raw material 1 are F atom and carboxyl group respectively, the product and R f The molar ratio of -OH is 1:1~5.

[0063] Furthermore, when the functional groups A and B in the raw material 1 are F atom and carboxyl group, respectively, the molar ratio of the product to the base is 1:1-5.

[0064] Another object of the present invention is to provide a method for preparing a hydrophobic thermoplastic polyimide resin, comprising the following steps:

[0065] S1, mixing the dianhydride monomer and the polar solvent, adding the diamine monomer, stirring, and obtaining a polyamic acid solution;

[0066] S2. Adding an organic base and a dehydrating agent to the polyamic acid solution, heating and stirring, adding the reaction solution to an alcohol solvent to precipitate a precipitate, collecting the precipitate, washing and drying, and obtaining a hydrophobic thermoplastic polyimide resin.

[0067] Further, the specific synthesis steps are as follows:

[0068] S1. At room temperature, mix the dianhydride monomer and the polar solvent until they are completely dissolved; then cool down and replace with inert gas, wait for the system to stabilize and reach the set low temperature environment, slowly add the diamine monomer under the inert gas atmosphere, and continue stirring at low temperature for 2 to 24 hours to obtain a polyamic acid solution.

[0069] S2. After adding an organic base to the polyamic acid solution obtained in step S1, a dehydrating agent is added dropwise. After the addition is completed, the mixture is stirred at 120-170°C for 2-24 hours. After the reaction is completed, the obtained solution is added dropwise to an alcohol solvent to precipitate a precipitate. The resin powder is obtained by vacuum filtration, and the resin powder is washed, filtered, and dried with an alcohol solvent to obtain a hydrophobic thermoplastic polyimide resin.

[0070] Furthermore, in S1, the molar ratio of the diamine monomer to the dianhydride monomer is 1:1.05-2.

[0071] Furthermore, in S1, the polar solvent is at least one of DMF, DMAc, NMP and DMSO.

[0072] Furthermore, in S1, the low temperature environment is ≤5°C.

[0073] Furthermore, in S1, the inert gas is argon and / or nitrogen.

[0074] Furthermore, in S1, the solid content of the polyamic acid solution is ≥5%.

[0075] Furthermore, the molar ratio of the dehydrating agent in S2 to the diamine monomer in S1 is 2 to 8:1.

[0076] Furthermore, in S2, the molar ratio of the organic base to the dehydrating agent is 1:1-2.

[0077] Furthermore, in S2, the organic base is at least one of triethylamine, ethylenediamine, diisopropylethylamine, diethylamine, pyridine, 2,6-lutidine, 2,4,6-trimethylpyridine, 2,6-di-tert-butylpyridine, 4-dimethylaminopyridine, and 1,8-diazabicycloundec-7-ene.

[0078] Furthermore, in S2, the dehydrating agent is at least one of acetic anhydride, propionic anhydride, acetyl chloride, dicyclohexylcarbocyanine, trifluoroacetic anhydride and thionyl chloride.

[0079] Furthermore, in S2, the alcohol solvent is at least one of methanol, ethanol, propanol, isopropanol, hexafluoroisopropanol, butanol, tert-butanol, and acetone.

[0080] Furthermore, in S2, the amount of the alcohol solvent used is 5 to 50 times the volume of the polar solvent.

[0081] The beneficial effects of the present invention are:

[0082] 1) The present invention effectively improves the hydrophobicity and various properties of thermoplastic polyimide resin by introducing fluorinated alkyl groups; compared with the existing method of coating the polyimide surface with a hydrophobic coating or constructing a micro-nano structure, the technical solution of the present invention avoids the reduction in structural strength caused by doping, and can maintain a longer hydrophobic period while improving the hydrophobicity of the polyimide.

[0083] 2) The present invention introduces a long-chain perfluoroalkane and a fluorinated alkyl chain as a hydrophobic structure and introduces a large number of fluorine atoms. The water contact angle of the obtained polyimide resin can reach more than 120°, showing excellent hydrophobicity.

[0084] 3) The introduction of long-chain perfluoroalkanes can act as large steric hindrance groups, reducing the regularity of the polymer chain and the T g and T m There is a significant reduction, which effectively improves the thermoplasticity of the polyimide resin. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0086] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0087] Figure 1 This is the NMR image of compound 3 obtained in Preparation Example 1 of the present invention;

[0088] Figure 2 The NMR image of the polyimide resin prepared in Example 1 of the present invention;

[0089] Figure 3The contact angle test result of one position of the polyimide resin prepared in Example 1 of the present invention;

[0090] Figure 4 The contact angle test result of one position of the polyimide resin prepared in Example 4 of the present invention;

[0091] Figure 5 The contact angle test result of one position of the polyimide resin prepared in Comparative Example 1 of the present invention is shown in FIG. DETAILED DESCRIPTION

[0092] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0093] Except as shown in the operating examples or otherwise indicated, all numbers used in the specification and claims to indicate the amount of ingredients, physicochemical properties, etc. are understood to be adjusted by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters listed in the above specification and the attached claims are approximate values, and those skilled in the art can use the teachings disclosed herein to seek to obtain the desired properties and appropriately change these approximate values. The use of numerical ranges expressed as endpoints includes all numbers within the range and any range within the range, for example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4 and 5, etc.

[0094] The present invention provides a hydrophobic thermoplastic polyimide resin having the following structural formula:

[0095]

[0096] Among them, n≥5;

[0097] Ar is selected from aromatic structures;

[0098] R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0099] In some embodiments, n≥50.

[0100] In some embodiments, n≥100.

[0101] In some embodiments, R 1 and R 2 For R f or -COOR f Any one of R f It is a fluorinated alkyl chain.

[0102] In some embodiments, R f -(CH2) x R y , where x ≥ 0, R y It is a perfluoroalkyl chain.

[0103] By introducing R y Perfluoroalkyl chain, as a hydrophobic structure, introduces a large number of fluorine atoms, and the water contact angle of the obtained polyimide resin can reach more than 120°, showing excellent hydrophobicity. In addition, the introduction of perfluoroalkyl chain can act as a large steric hindrance group to reduce the regularity of the polymer chain, and the T of the obtained polyimide resin is g and T m There is a significant reduction, which effectively improves the thermoplasticity of the polyimide resin.

[0104] In some embodiments, R f Any of the following structures:

[0105]

[0106] Among them, m≥0.

[0107] In some embodiments, Ar is any one of the following structures:

[0108] .

[0109] The preparation method of the hydrophobic thermoplastic polyimide resin comprises at least the following steps:

[0110] S1, mixing the dianhydride monomer and the polar solvent, adding the diamine monomer, stirring, and obtaining a polyamic acid solution;

[0111] S2. Adding an organic base and a dehydrating agent to the polyamic acid solution, heating and stirring, adding the reaction solution to an alcohol solvent to precipitate a precipitate, collecting the precipitate, washing and drying, and obtaining a hydrophobic thermoplastic polyimide resin.

[0112] In some embodiments, the method for preparing a hydrophobic thermoplastic polyimide resin comprises at least the following steps:

[0113] S1. At room temperature, mix the dianhydride monomer and the polar solvent until they are completely dissolved; then cool down and replace with inert gas, wait for the system to stabilize and reach the set low temperature environment, slowly add the diamine monomer under the inert gas atmosphere, and continue stirring at low temperature for 2 to 24 hours to obtain a polyamic acid solution.

[0114] S2. After adding an organic base to the polyamic acid solution obtained in step S1, a dehydrating agent is added dropwise. After the addition is completed, the mixture is stirred at 120-170°C for 2-24 hours. After the reaction is completed, the obtained solution is added dropwise to an alcohol solvent to precipitate a precipitate. The resin powder is obtained by vacuum filtration, and the resin powder is washed, filtered, and dried with an alcohol solvent to obtain a hydrophobic thermoplastic polyimide resin.

[0115] In some embodiments, in S1, the dianhydride monomer is any one of the following structures:

[0116]

[0117]

[0118] .

[0119] In some embodiments, in S1, the structural formula of the diamine monomer is:

[0120]

[0121] Among them, R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0122] In some embodiments, in S1, the diamine monomer is any one of the following structures:

[0123]

[0124] Among them, R f It is a fluorinated alkyl chain.

[0125] In some embodiments, in S1, the molar ratio of the diamine monomer to the dianhydride monomer is 1:1.05-2.

[0126] In some embodiments, in S1, the polar solvent is at least one of DMF, DMAc, NMP, and DMSO.

[0127] In some embodiments, in S1, the low temperature environment is ≤5°C.

[0128] In some embodiments, in S1, the inert gas is argon and / or nitrogen.

[0129] In some embodiments, in S1, the solid content of the polyamic acid solution is ≥5%.

[0130] In some embodiments, the molar ratio of the dehydrating agent in S2 to the diamine monomer in S1 is 2 to 8:1.

[0131] In some embodiments, in S2, the molar ratio of the organic base to the dehydrating agent is 1:1-2.

[0132] In some embodiments, in S2, the organic base is at least one of triethylamine, ethylenediamine, diisopropylethylamine, diethylamine, pyridine, 2,6-lutidine, 2,4,6-trimethylpyridine, 2,6-di-tert-butylpyridine, 4-dimethylaminopyridine, and 1,8-diazabicycloundec-7-ene.

[0133] In some embodiments, in S2, the dehydrating agent is at least one of acetic anhydride, propionic anhydride, acetyl chloride, dicyclohexylcarbocyanine, trifluoroacetic anhydride and thionyl chloride.

[0134] In some embodiments, in S2, the alcohol solvent is at least one of methanol, ethanol, propanol, isopropanol, hexafluoroisopropanol, butanol, tert-butanol, and acetone.

[0135] In some embodiments, in S2, the amount of the alcohol solvent used is 5 to 50 times the volume of the polar solvent.

[0136] In some embodiments, the synthesis route of the diamine monomer is as follows:

[0137]

[0138] Among them, R f is a fluorinated alkyl chain;

[0139] R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated.

[0140] In some embodiments, when the functional group A and / or B in the raw material 1 is an F atom, the specific synthesis steps of the diamine monomer are as follows:

[0141] Step 1: Raw materials 1, R f -OH and a base are added to a polar solvent, heated and stirred, and after the reaction is completed, the reaction solution is poured into water and filtered to obtain intermediate 1;

[0142] Step 2: adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0143] In some embodiments, when the functional group A and / or B in the raw material 1 is an F atom, the specific synthesis steps of the diamine monomer are as follows:

[0144] Step 1: Raw materials 1, R f -OH and a base are added to a polar solvent, and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the reaction solution is poured into water, filtered to obtain a solid, and then washed and dried to obtain intermediate 1;

[0145] Step 2: Add intermediate 1, p-aminophenol and base to a polar solvent, stir at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pour the reaction solution into water, filter to obtain a solid, and obtain a diamine monomer after washing and drying.

[0146] In some embodiments, in step 1, raw material 1 and R f The molar ratio of -OH is 1:1~5.

[0147] In some embodiments, in step 1, the molar ratio of raw material 1 to base is 1:1-5.

[0148] In some embodiments, in step 2, the molar ratio of intermediate 1 to p-aminophenol is 1:1-5.

[0149] In some embodiments, in step 2, the molar ratio of intermediate 1 to base is 1:1-5.

[0150] In some embodiments, in step 1 and / or step 2, the base is at least one of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium tert-butoxide, potassium tert-butoxide, and sodium hydride.

[0151] In some embodiments, in step 1 and / or step 2, the polar solvent is at least one of DMF, DMAc, and NMP.

[0152] In some embodiments, when the functional group A and / or B in the raw material 1 is a carboxyl group, the specific synthesis steps of the diamine monomer are:

[0153] Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, the temperature is raised and refluxed with stirring, and after the reaction is completed, recrystallization is performed to obtain intermediate 1;

[0154] Step (2), adding intermediate 1, p-aminophenol and base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0155] In some embodiments, when the functional group A and / or B in the raw material 1 is a carboxyl group, the specific synthesis steps of the diamine monomer are:

[0156] Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, and the mixture is refluxed and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the toluene is removed by rotary evaporation, and the intermediate 1 is obtained by recrystallization;

[0157] Step (2), adding intermediate 1, p-aminophenol and a base to a polar solvent, stirring at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pouring the reaction solution into water, filtering to obtain a solid, and washing and drying to obtain a diamine monomer.

[0158] In some embodiments, in step (1), raw material 1 and R f The molar ratio of -OH is 1:1~5.

[0159] In some embodiments, in step (1), the acid catalyst is at least one of sulfuric acid, methanesulfonic acid, and p-toluenesulfonic acid.

[0160] In some embodiments, in step (1), the molar ratio of raw material 1 to acid catalyst is 1:0.01-0.25.

[0161] In some embodiments, in step (2), the molar ratio of intermediate 1 to p-aminophenol is 1:1-5.

[0162] In some embodiments, in step (2), the molar ratio of intermediate 1 to base is 1:1-5.

[0163] In some embodiments, in step (2), the base is at least one of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium tert-butoxide, potassium tert-butoxide, and sodium hydride.

[0164] In some embodiments, in step (2), the polar solvent is at least one of DMF, DMAc, and NMP.

[0165] In some embodiments, when the functional groups A and B in the raw material 1 are F atom and carboxyl group, respectively, the specific synthesis steps of the diamine monomer are:

[0166] Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, the temperature is raised to reflux and stirred for reaction, and after the reaction is completed, recrystallization is performed to obtain the product;

[0167] Step 1: The product obtained in step (1), R f-OH and a base are added to a polar solvent, the temperature is raised and stirred for reaction, after the reaction is completed, the reaction solution is poured into water and filtered to obtain intermediate 1;

[0168] Step 2: adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

[0169] In some embodiments, when the functional groups A and B in the raw material 1 are F atom and carboxyl group, respectively, the specific synthesis steps of the diamine monomer are:

[0170] Step (1), raw material 1, R f -OH and acid catalyst are added to toluene, and refluxed and stirred at 80°C~150°C for 2~24h. After the reaction is completed, the toluene is removed by rotary evaporation, and the product is obtained by recrystallization;

[0171] Step 1: The product obtained in step (1), R f -OH and a base are added to a polar solvent, and stirred at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, the reaction solution is poured into water, filtered to obtain a solid, and then washed and dried to obtain intermediate 1;

[0172] Step 2: Add intermediate 1, p-aminophenol and base to a polar solvent, stir at 80°C to 150°C for 2 to 24 hours. After the reaction is completed, pour the reaction solution into water, filter to obtain a solid, and obtain a diamine monomer after washing and drying.

[0173] In some embodiments, in step (1), raw material 1 and R f The molar ratio of -OH is 1:1~5.

[0174] In some embodiments, in step (1), the acid catalyst is at least one of sulfuric acid, methanesulfonic acid, and p-toluenesulfonic acid.

[0175] In some embodiments, in step (1), the molar ratio of raw material 1 to acid catalyst is 1:0.01-0.25.

[0176] In some embodiments, in step 1, the product is reacted with R f The molar ratio of -OH is 1:1~5.

[0177] In some embodiments, in step 1, the molar ratio of the product to the base is 1:1-5.

[0178] In some embodiments, in step 2, the molar ratio of intermediate 1 to p-aminophenol is 1:1-5.

[0179] In some embodiments, in step 2, the molar ratio of intermediate 1 to base is 1:1-5.

[0180] In some embodiments, in step 1 and / or step 2, the base is at least one of potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide, potassium ethoxide, sodium tert-butoxide, potassium tert-butoxide, and sodium hydride.

[0181] In some embodiments, in step 1 and / or step 2, the polar solvent is at least one of DMF, DMAc, and NMP.

[0182] Example

[0183] The following examples describe the disclosure of the present invention in more detail, and these examples are intended for illustrative purposes only, as various modifications and variations within the scope of the disclosure of the present invention will be apparent to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are by weight, and all reagents used in the examples are commercially available or synthesized according to conventional methods and can be used directly without further processing, and the instruments used in the examples are commercially available.

[0184] The CAS numbers of the key raw materials used in the examples and comparative examples are shown in Table 1.

[0185] Table 1

[0186]

[0187] Preparation Example 1

[0188] This preparation example prepared a diamine monomer, the specific structural formula of which is as follows:

[0189]

[0190] Its synthetic route is as follows:

[0191]

[0192] Specific synthesis steps:

[0193] Step 1: At room temperature, compound 1 (3,5-dichloro-4-fluorobenzotrifluoride (raw material 1), 2.33 g, 10 mmol), 2-perfluorooctylethanol (R f -OH, 5.57 g, 12 mmol) and potassium carbonate (base, 2.76 g, 20 mmol) were added to DMF (20 mL) solvent and stirred at 120 °C for 12 h. After the reaction was completed, the reaction solution was poured into water and filtered to obtain a solid. After washing and drying, compound 2 (i.e., intermediate 1) was obtained.

[0194] Step 2: At room temperature, compound 2 (intermediate 1, 6.77 g, 10 mmol), p-aminophenol (2.62 g, 24 mmol) and sodium hydroxide (0.8 g, 20 mmol) were added to DMF (20 mL), and stirred at 120 °C for 12 h. After the reaction, the reaction solution was poured into water, filtered to obtain a solid, and after washing and drying, compound 3, i.e., the target diamine monomer, was obtained.

[0195] NMR data of compound 3: 1 H NMR (500 MHz, Chloroform-d) δ 6.97 – 6.87 (m,4H), 6.78–6.66 (m, 4H), 6.58 (s, 2H), 4.32 (t, J = 7.1 Hz, 2H), 2.04 (m, 2H).

[0196] Preparation Example 2

[0197] This preparation example prepared a diamine monomer, the specific structural formula of which is as follows:

[0198]

[0199] Its synthetic route is as follows:

[0200]

[0201] Specific synthesis steps:

[0202] Step (1), compound 4 (3,5-dichloro-4-fluorobenzoic acid (raw material 1), 2.09 g, 10 mmol), 2-perfluorooctylethanol (R f -OH, 5.57 g, 12 mmol), methanesulfonic acid (acid catalyst, 0.096 g, 1 mmol) were added to toluene (50 mL), and the reaction was refluxed with stirring for 12 h. After the reaction was completed, toluene was evaporated away by a rotary evaporator, and compound 5 (product) was obtained by recrystallization.

[0203] Step 1. At room temperature, compound 5 (product, 6.55 g, 10 mmol), 2-perfluorooctylethanol (5.57 g, 12 mmol) and potassium carbonate (2.76 g, 20 mmol) were added to DMF (20 mL) and stirred at 120 °C for 12 h. After the reaction, the reaction solution was poured into water and the solid was filtered. After washing and drying, the product compound 6 (intermediate 1) was obtained.

[0204] Step 2: Add compound 6 (intermediate 1, 10.99 g, 10 mmol), p-aminophenol (2.62 g, 24 mmol) and sodium hydroxide (0.8 g, 20 mmol) to DMF (20 mL) at room temperature and stir at 120 °C for 12 h. After the reaction, pour the reaction solution into water and filter to obtain a solid. After washing and drying, compound 7, i.e., the target diamine monomer, is obtained.

[0205] Example 1

[0206] This embodiment provides a hydrophobic thermoplastic polyimide, the structure of which is as follows:

[0207]

[0208] The synthesis method of the hydrophobic thermoplastic polyimide resin of this structure is as follows:

[0209] S1. At room temperature, mix pyromellitic anhydride (2.398 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) until they are completely dissolved; then cool down and replace with argon, detect the reaction solution with a thermometer, wait for the system temperature to drop to -5 °C, and then slowly add the diamine monomer compound 3 (8.22 g, 10 mmol) synthesized in Example 1 while maintaining an inert gas atmosphere. After continuing to stir at low temperature (-5 °C) for 16 h, add a capping agent (phthalic anhydride), and continue to react for 2 h to obtain a polyamic acid solution.

[0210] S2. Add pyridine (0.8 mL, 10 mmol) to the polyamic acid solution obtained in S1, and slowly drop the dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, heat to 150 °C and stir for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, drop the obtained light yellow solution into the stirred ethanol, and a light yellow precipitate is immediately precipitated. The light yellow resin powder is obtained by vacuum filtration, and finally the light yellow powder is washed, filtered and dried with ethanol to obtain the target hydrophobic thermoplastic polyimide resin.

[0211] NMR data of hydrophobic thermoplastic polyimide resin: 1 H NMR (500 MHz, Chloroform- d ) δ8.43 (s, 2H), 8.30 – 8.11 (m, 2H), 7.26 – 7.18 (m, 2H), 7.16 – 7.08 (m, 2H),7.04 – 6.96 (m, 2H), 6.89 (d, J= 1.1 Hz, 2H), 4.22 (t, J = 7.1 Hz, 2H), 2.01 (m,2H).

[0212] Example 2

[0213] This embodiment provides a hydrophobic thermoplastic polyimide, the structure of which is as follows:

[0214]

[0215] The synthesis method of the thermoplastic polyimide resin of this structure is as follows:

[0216] S1. At room temperature, mix pyromellitic anhydride (2.398 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) until they are completely dissolved; then cool down and replace with argon, detect the reaction solution with a thermometer, wait for the system temperature to drop to -5 °C, and then slowly add the diamine monomer (compound 7, 12.44 g, 10 mmol) synthesized in Example 2 while maintaining an inert gas atmosphere, continue stirring at low temperature (-5 °C) for 16 h, add a capping agent (phthalic anhydride), and continue to react for 2 h to obtain a polyamic acid solution.

[0217] S2. Add pyridine (0.8 mL, 10 mmol) to the polyamic acid solution obtained in S1, and slowly drop the dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, heat to 100 °C and stir for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, slowly drop the obtained light yellow solution into the rapidly stirred ethanol to precipitate a light yellow precipitate. By vacuum filtration, a light yellow resin powder is obtained, and finally the light yellow powder is washed, filtered and dried with ethanol to obtain the target hydrophobic thermoplastic polyimide resin.

[0218] Example 3

[0219] This embodiment provides a hydrophobic thermoplastic polyimide, the structure of which is as follows:

[0220]

[0221] The synthesis method of the thermoplastic polyimide resin of this structure is as follows:

[0222] S1. At room temperature, 3,3',4,4'-biphenyltetracarboxylic dianhydride (3.236 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) were mixed until completely dissolved; then the temperature was lowered and argon gas was replaced, and the reaction solution was tested by a thermometer. After the system temperature dropped to -5 °C, the fluorinated diamine monomer compound 3 (8.22 g, 10 mmol) synthesized in Example 1 was slowly added under an inert gas atmosphere, and the mixture was stirred at low temperature (-5 °C) for 16 h, and then a capping agent (phthalic anhydride) was added. The reaction was continued for 2 h to obtain a polyamic acid solution.

[0223] S2. Add pyridine (0.8 mL, 10 mmol) to the polyamic acid solution obtained in S1, and slowly drop the dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, stir at 100 °C for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, the obtained light yellow solution is dropped into ethanol to precipitate a light yellow precipitate. The light yellow resin powder is obtained by vacuum filtration, and finally the light yellow powder is washed, filtered and dried with ethanol to obtain the target hydrophobic thermoplastic polyimide resin.

[0224] Example 4

[0225] This embodiment provides a hydrophobic thermoplastic polyimide, the structure of which is as follows:

[0226]

[0227] The synthesis method of the thermoplastic polyimide resin of this structure is as follows:

[0228] S1. At room temperature, 3,3',4,4'-biphenyltetracarboxylic dianhydride (3.236 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) were mixed until completely dissolved; then the temperature was lowered and argon gas was replaced, and the reaction solution was tested by a thermometer. After the system temperature dropped to -5 °C, the fluorinated diamine monomer compound 7 (12.44 g, 10 mmol) synthesized in Example 2 was added while maintaining an inert gas atmosphere. After stirring at low temperature (-5 °C) for 16 h, a capping agent (phthalic anhydride) was added, and the reaction was continued for 2 h to obtain a polyamic acid solution.

[0229] S2. Add pyridine (0.8 mL, 10 mmol) to the polyamic acid solution obtained in S1, and slowly drop the dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, heat to 150 °C and stir for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, drop the obtained light yellow solution into ethanol to precipitate a light yellow precipitate. By vacuum filtration, a light yellow resin powder is obtained, and finally the light yellow powder is washed, filtered and dried with ethanol to obtain the target hydrophobic thermoplastic polyimide resin.

[0230] Comparative Example 1

[0231] This comparative example provides a thermoplastic polyimide, the structure of which is as follows:

[0232]

[0233] The synthesis method of the thermoplastic polyimide resin of this structure is as follows:

[0234] S1. At room temperature, mix pyromellitic anhydride (2.398 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) until they are completely dissolved; then cool down and replace with argon, detect the reaction solution with a thermometer, wait for the system temperature to drop to -5 °C, and then slowly add 1,3-bis(4'-aminophenoxy)benzene (2.92 g, 10 mmol) while maintaining an inert gas atmosphere. After stirring at low temperature (-5 °C) for 16 h, add a capping agent (phthalic anhydride) and continue the reaction for 2 h to obtain a polyamic acid solution.

[0235] S2. Add pyridine (0.8 mL, 10 mmol) to the polyamic acid solution obtained in S1, and dropwise add dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, heat to 150 °C and stir for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, drop the obtained light yellow solution into ethanol, and a light yellow precipitate is immediately precipitated. By vacuum filtration, a light yellow resin powder is obtained, and finally the light yellow powder is washed, filtered, and dried with ethanol to obtain the target thermoplastic polyimide.

[0236] Comparative Example 2

[0237] This comparative example provides a thermoplastic polyimide, the structure of which is as follows:

[0238]

[0239] The synthesis method of the thermoplastic polyimide resin of this structure is as follows:

[0240] S1. At room temperature, 3,3',4,4'-biphenyltetracarboxylic dianhydride (3.236 g, 11 mmol) and N-methylpyrrolidone NMP (100 ml) were mixed until completely dissolved; then the temperature was lowered and argon gas was replaced, and the reaction solution was tested by a thermometer. After the system temperature dropped to -5 °C, 1,3-bis(4'-aminophenoxy)benzene (2.92 g, 10 mmol) was slowly added under an inert gas atmosphere, and the mixture was stirred at low temperature (-5 °C) for 16 h, and then a capping agent (phthalic anhydride) was added. The reaction was continued for 2 h to obtain a polyamic acid (PAA) solution.

[0241] S2. Add pyridine (0.8 mL, 10 mmol) to the PAA solution obtained in S1, and slowly drop the dehydrating agent acetic anhydride (1.88 mL, 20 mmol). After the dropwise addition is completed, heat to 150 °C and stir for 16 hours, and the solution turns from transparent to light yellow. After the reaction is completed, drop the obtained light yellow solution into ethanol to precipitate a light yellow precipitate. By vacuum filtration, a light yellow resin powder is obtained, and finally the light yellow powder is washed, filtered and dried with ethanol to obtain the target thermoplastic polyimide.

[0242] Test Case

[0243] The polyimide resins prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to performance tests, and the test results are shown in Table 2. g is the glass transition temperature, T m The melting temperature is used for the water contact angle test. The sample is molded and five locations on the surface of each sample are tested to take the average value.

[0244] Table 2

[0245]

[0246] From Table 2 and Appendix Figure 1-3 The water contact angle test results show that in Examples 1-4, the long-chain perfluoroalkane has a good improvement on hydrophobicity and thermoplasticity, and the water contact angle of the obtained polyimide resin is ≥123°, T g 243-255℃, T m The contact angle of Examples 1-4 is significantly higher than that of Comparative Examples 1-2, and has a better hydrophobic effect. The Tg of Examples 1-4 is significantly lower than that of Comparative Examples 1-2, and has better flexibility and processing performance.

[0247] In particular, after the introduction of two long-chain perfluoroalkanes, the water contact angles of Examples 2 and 4 can reach above 140°, showing better hydrophobicity than Examples 1 and 3.

[0248] At the same time, the introduction of long-chain perfluoroalkane can act as a large steric hindrance group to reduce the regularity of the polymer chain and effectively improve the thermoplasticity of the polymer. As shown in Table 2, after the introduction of perfluoroalkyl chain, the T g and T m The T g and T m Lower than Example 1 and Example 3 respectively.

[0249] The present invention illustrates the detailed process equipment and process flow of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed process equipment and process flow, that is, it does not mean that the present invention must rely on the above-mentioned detailed process equipment and process flow to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, change of structural morphology, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0250] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0251] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0252] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

[0253] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A hydrophobic thermoplastic polyimide resin, characterized in that: The hydrophobic thermoplastic polyimide resin has the following structural formula: Among them, n≥5; Ar is selected from aromatic structures; R 1 and / or R 2 is a fluorinated alkyl chain, and R 1 and R 2 The same or independent and unrelated.

2. The hydrophobic thermoplastic polyimide resin according to claim 1, characterized in that: The R 1 and R 2 For R f or -COOR f Any one of the R f It is a fluorinated alkyl chain.

3. The hydrophobic thermoplastic polyimide resin according to claim 2, characterized in that: The R f -(CH2) x R y , where x ≥ 0, R y It is a perfluoroalkyl chain.

4. The hydrophobic thermoplastic polyimide resin according to claim 2, characterized in that: R f Any of the following structures: Among them, m≥0.

5. The hydrophobic thermoplastic polyimide resin according to claim 1, characterized in that: Ar is any of the following structures: 。 6. The hydrophobic thermoplastic polyimide resin according to claim 1, characterized in that: The raw materials for preparing the hydrophobic thermoplastic polyimide resin include diamine monomers and dianhydride monomers, and the structural formula of the diamine monomer is: Among them, R 1 and / or R 2 is a fluorinated alkyl chain, and R 1 and R 2 The same or independent and unrelated; The dianhydride monomer is any one of the following structures: 。 7. The hydrophobic thermoplastic polyimide resin according to claim 6, characterized in that: The diamine monomer is any one of the following structures: Where R f It is a fluorinated alkyl chain.

8. The hydrophobic thermoplastic polyimide resin according to claim 6, characterized in that: The synthetic route of the diamine monomer is as follows: Among them, R f is a fluorinated alkyl chain; R 1 and / or R 2 is a fluorinated alkyl chain, R 1 and R 2 The same or independent and unrelated; The synthesis steps of the diamine monomer are: When the functional group A and / or B in the raw material 1 is F atom, the synthesis steps are: Step 1: Raw materials 1, R f -OH and a base are added to a polar solvent, the temperature is raised and stirred for reaction, after the reaction is completed, the reaction solution is poured into water and filtered to obtain intermediate 1; Step 2, adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer; When the functional group A and / or B in the raw material 1 is a carboxyl group, the synthesis steps are: Step (1), raw material 1, R f -OH and an acid catalyst are added to toluene, and the temperature is raised to reflux and stirred for reaction. After the reaction is completed, recrystallization is performed to obtain intermediate 1; Step (2), adding intermediate 1, p-aminophenol and a base to a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer; When the functional groups A and B in the raw material 1 are F atom and carboxyl group respectively, the synthesis steps are: Step (1), adding raw material 1, Rf-OH and acid catalyst into toluene, heating, refluxing and stirring to react, after the reaction is completed, recrystallizing to obtain a product; Step 1, adding the product obtained in step (1), Rf-OH and a base to a polar solvent, heating and stirring to react, after the reaction is completed, pouring the reaction solution into water, filtering to obtain an intermediate 1; Step 2: adding intermediate 1, p-aminophenol and a base into a polar solvent, heating and stirring, and after the reaction is completed, recrystallizing to obtain a diamine monomer.

9. The method for preparing a hydrophobic thermoplastic polyimide resin according to any one of claims 1 to 8, characterized in that: The steps include: S1, mixing the dianhydride monomer and the polar solvent, adding the diamine monomer, stirring, and obtaining a polyamic acid solution; S2. Adding an organic base and a dehydrating agent to the polyamic acid solution, heating and stirring, adding the reaction solution to an alcohol solvent to precipitate a precipitate, collecting the precipitate, washing and drying, and obtaining a hydrophobic thermoplastic polyimide resin.

10. The method for preparing a hydrophobic thermoplastic polyimide resin according to claim 9, characterized in that: The molar ratio of the diamine monomer to the dianhydride monomer is 1:1.05-2; The molar ratio of the organic base to the dehydrating agent is 1:1-2; The organic base is at least one of triethylamine, ethylenediamine, diisopropylethylamine, diethylamine, pyridine, 2,6-lutidine, 2,4,6-trimethylpyridine, 2,6-di-tert-butylpyridine, 4-dimethylaminopyridine, and 1,8-diazabicycloundec-7-ene; The dehydrating agent is at least one of acetic anhydride, propionic anhydride, acetyl chloride, dicyclohexylcarbocyanine, trifluoroacetic anhydride, and thionyl chloride; The alcohol solvent is at least one of methanol, ethanol, propanol, isopropanol, hexafluoroisopropanol, butanol, tert-butanol and acetone.

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