A high-toughness thermoplastic polyimide elastomer and a method for preparing the same

Abstract

The application discloses a high-strength and high-toughness thermoplastic polyimide elastomer and a preparation method thereof. The high-strength and high-toughness thermoplastic polyimide elastomer of the application combines the processability / tensile property of the flexible chain segment and the high toughness / thermal stability / chemical resistance of PI. By adjusting the ratio of the soft and hard chain segments, the tensile property and mechanical toughness of the material can be balanced, so that the high T d g. The data of the examples show that the tensile strength of the elastomer prepared by the application can reach 39 MPa at most, the elongation at break can reach 1050%, and the toughness can reach 194 MJ / m 3 g.

Description

Technical Field

[0001] This invention relates to a high-strength and tough thermoplastic polyimide elastomer and its preparation method, belonging to the field of core materials for flexible electronic devices. Background Technology

[0002] Over the past decade, research on intrinsically stretchable materials in the field of stretchable electronics has flourished, targeting applications such as health monitoring devices, electronic skin, soft robots, human-machine interfaces, and implantable devices. With the urgent need for new materials in flexible electronics, intrinsically stretchable materials, ranging from conductors and semiconductors to dielectrics, have been widely developed to construct diverse stretchable devices. Simultaneously, with the popularization of bio-integrated electronics technology, this field is accelerating its cross-integration with biomedicine. The core characteristic of stretchable electronic devices lies in their mechanical stretchability, meaning that the device can maintain its function and performance under large deformations while maintaining good skin contact to improve comfort. Flexible electronic devices also need to possess properties such as mechanical toughness, optical transparency, thermal stability, chemical stability, low water absorption, and processability. However, the high toughness and high stretchability or low stiffness of intrinsically stretchable materials are often incompatible. Researchers have explored various strategies to overcome the stiffness-toughness trade-off. However, it remains extremely challenging for a single system to simultaneously satisfy all of these properties, as its mechanical properties often conflict with other essential properties. Materials possessing multiple properties such as strength, stretchability, toughness, optical transparency, and processability are in high demand in the field of flexible electronics. However, the development of such materials has always faced challenges due to the difficulty of balancing these properties.

[0003] Currently, intrinsically stretchable polymers with balanced properties (for substrates, encapsulation layers, or functional layers) remain very limited. Commercially available intrinsically stretchable materials, such as low-modulus polydimethylsiloxane (PDMS) and... Silicone elastomers, such as silicone, are widely used in flexible electronics. However, these highly stretchable elastomers suffer from poor moldability, low strength, and insufficient toughness, making them unsuitable for device fabrication. Another type of commercially available intrinsically stretchable material consists of tunable elastomer copolymers, such as thermoplastic polyurethane (TPU), styrene-butadiene-styrene block copolymers (SBS), and polystyrene-poly(ethylene-butene)-polystyrene triblock copolymers (SEBS). These copolymers exhibit high stretchability, low elastic modulus, and good processability, with commercial thermoplastic PU and SEBS demonstrating high toughness. However, their low decomposition temperature (Td), insufficient chemical / thermal stability, and poor long-term moisture resistance limit their application in wearable flexible electronics.

[0004] To overcome the limitations of the aforementioned elastic copolymers, this invention proposes a high-strength and tough thermoplastic elastomer synthesized by random block copolymerization of rigid and flexible monomers with polyimide (PI) as the main chain. The excellent chemical / mechanical / thermal stability, biocompatibility, and high barrier properties of PI materials provide advantages for the development of target materials. Studies have shown that introducing flexible segments such as PDMS into the PI main chain can improve the stretchability of the copolymer (Polymer 2020, 210, 122966; Macromolecules 2002, 35, 5256), but its application in flexible electronics is still limited by poor processability with organic solvents, high glass transition temperature (hindering molding and melt processing), dark coloring, and poor stretchability. While existing transparent polymer materials (such as polycarbonate and polyether ester amide) have improved transparency and stretchability through copolymerization modification, their heat resistance is insufficient, and it is difficult to balance strength and toughness. For example, while the polyimide elastomer disclosed in patent CN118126324A improves the problems of deep color and difficult processing of polyimide, the tensile properties of the prepared elastomer are limited. The polyimide elastomer disclosed in patent CN112062956A improves the mechanical properties of polyimide elastomers by adding polyfunctional monomers, but the mechanical properties of the prepared elastomer still need further improvement, and this method does not consider the optical properties and soluble processing properties of the polyimide elastomer.

[0005] Therefore, developing a high-strength and high-toughness thermoplastic polyimide elastomer that combines high transparency, high temperature resistance, solubility and processing, and excellent tensile properties has become a technical challenge that urgently needs to be solved in this field. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention prepares a high-strength and high-toughness thermoplastic polyimide elastomer.

[0007] This invention is achieved through the following technical solution:

[0008] The first objective of this invention is to provide a high-strength and high-toughness thermoplastic polyimide elastomer with the following general structural formula:

[0009]

[0010] Wherein, R1 is a dianhydride monomer, R2 is a rigid diamine monomer, R3 is a flexible diamine monomer, and the value range of q+p is 2-15, and neither q nor p is 0.

[0011] In one embodiment of the present invention, R1 has one of the following structures:

[0012]

[0013] In one embodiment of the present invention, R2 has one of the following structural formulas:

[0014]

[0015] In one embodiment of the present invention, the structural formula of R3 is one of the following:

[0016]

[0017] Carjill priamine 1071, 1074, 1073;

[0018] Wherein, the value range of n1 is 5-13, the value range of n2 is 33-68, the value range of n3 is 12-31, the value range of n4 is 7-64, and the value range of n5 is 17-43.

[0019] In one embodiment of the present invention, the high-strength and tough thermoplastic polyimide elastomer is obtained by imidization of polyamic acid (PAA), and the structural changes before and after imidization are as follows:

[0020]

[0021] Wherein, R1 is a dianhydride monomer, R2 is a rigid diamine monomer, R3 is a flexible diamine monomer, and the value range of q+p is 2-15, and neither q nor p is 0.

[0022] The second objective of this invention is to provide a method for preparing a high-strength and tough thermoplastic polyimide elastomer, comprising the following steps: under a protective atmosphere, mixing a dianhydride monomer, a rigid diamine monomer, a flexible diamine monomer, and a solvent to perform a polymerization reaction to generate polyamic acid (PAA), adding a catalyst for imidization to obtain a thermoplastic polyimide elastomer; wherein the molar ratio of the rigid diamine monomer to the flexible diamine monomer is 1:9 to 6:4; and the monomer solid content is 5% to 100%.

[0023] In one embodiment of the present invention, the molar ratio of dianhydride monomer to diamine monomer is preferably 10.1 to 10.5:10, wherein the diamine monomer is the total amount of rigid and flexible diamine monomers. This molar ratio is used to achieve dianhydride end-capping.

[0024] In one embodiment of the present invention, the molar ratio of rigid diamine monomer to flexible diamine monomer is preferably 1:9 to 6:4, more preferably 2:8 to 3:7, and most preferably 3:7.

[0025] In one embodiment of the present invention, the imidization includes chemical imidization or thermal imidization.

[0026] In one embodiment of the present invention, the catalyst added for chemical imidization is an equal amount of acetic anhydride and pyridine; the molar ratio of acetic anhydride, pyridine and dianhydride monomer is 2-12:2-12:1.

[0027] In one embodiment of the present invention, a catalyst and a dehydrating agent are added during thermal imidization. The catalyst is preferably isoquinoline or p-hydroxybenzoic acid; the dehydrating agent is preferably toluene; and the catalyst accounts for 0.5 to 2% of the total mass of the monomer.

[0028] In one embodiment of the present invention, the temperature range of thermal imidization is 120-200°C, and the thermal imidization time is 4-24 hours.

[0029] In one embodiment of the present invention, the monomer solid content is preferably 5-100%, more preferably 20-80%, wherein the monomer is the total amount of dianhydride monomer, rigid diamine monomer and flexible diamine monomer.

[0030] In one embodiment of the present invention, the solvent is preferably one of N-methylpyrrolidone (NMP), sulfolane, 1,2-dichlorobenzene, m-cresol, and 1,4-butyrolactone (GBL), more preferably NMP, m-cresol, or GBL, and most preferably GBL.

[0031] In one embodiment of the present invention, the dianhydride monomer is preferably at least one selected from hexafluorodianhydride (6FDA), cyclobutanetetracarboxylic dianhydride (CBDA), hydrogenated pyromellitic dianhydride (HPMDA), 4,4'-diphenyl ether dianhydride (ODPA), 2,3,3',4'-diphenyl ethertetracarboxylic dianhydride (α-ODPA), 2,3,3',4'-biphenyltetracarboxylic dianhydride (α-BPDA), bisphenol A type diether dianhydride (BPADA), 1,2,3,4-butanetetracarboxylic dianhydride (BDA), p-phenylene-bisphenyltriester dianhydride (TAHQ), 3,3,4,4-diphenylsulfone tetracarboxylic dianhydride (DSDA), 1,4,5,8-naphthalenetetracarboxylic anhydride (NTDA), and 4,4'-terephthalodioxydiphthalic anhydride (HQDPA).

[0032] In one embodiment of the present invention, the rigid diamine monomer is preferably at least one selected from terephthalic acid dihydrazide (TPDH), hydrazine carbonate (CBH), oxaloyl dihydrazide (ODH), 4,4'-diaminodiphenyl ether (ODA), adipate dihydrazide (ADH), succinic acid dihydrazide (SDH), 1,3-bis(4-aminophenoxy)benzene (TPE-R), 1,4-bis(4-aminophenoxy)benzene (TPE-Q), 2-(4-aminophenyl)-5-aminobenzimidazole (APBIA), 2-(4-aminophenyl)-5-aminobenzoxazole (APBOA), 4-aminophenyl 4-aminobenzoate (APAB), 4,4'-diaminobenzoyl aniline (DABA), p-phenylenediamine (p-PDA), and 4,4'-diaminodiphenylmethane (MDA).

[0033] In one embodiment of the present invention, the flexible diamine monomer is preferably one of poly-1,4-butanediol bis(4-aminobenzoate) (P1000), polyetheramine (PEA), amino-terminated polybutadiene, polymethylsiloxane (APPS), amino-terminated polycaprolactone (H2N-PCL-NH2), 1,3-propanediol bis(4-aminobenzoate) (740M), Carjill priamine 1071, 1074, and 1073.

[0034] In one embodiment of the present invention, the polymerization reaction temperature is preferably -20 to 120°C, more preferably 0 to 80°C.

[0035] In one embodiment of the present invention, the polymerization reaction time is preferably 0.5 to 24 hours, more preferably 2 to 12 hours.

[0036] The beneficial effects of this invention are:

[0037] This invention designs and synthesizes a high-strength and tough thermoplastic elastomer with hard / soft segments containing a PI backbone. Compared with traditional block copolymers, which require multiple complex synthesis steps, are time-consuming and difficult to scale up, this invention can be prepared in a one-pot method and has the potential for large-scale application.

[0038] This invention relates to a high-strength and tough thermoplastic polyimide elastomer that combines the processability / stretchability of flexible segments with the high toughness / thermal stability / chemical resistance of polyimide. By adjusting the ratio of soft to hard segments, a trade-off can be struck between the material's stretchability and mechanical toughness, thereby maintaining high tensile strength. d While maintaining chemical resistance, this invention overcomes the shortcomings of insufficient toughness in existing commercially available elastomers such as PDMS. Example data shows that the elastomer prepared by this invention can achieve a tensile strength of up to 39 MPa, an elongation at break of up to 1050%, and a toughness of 194 MJ / m. 3 .

[0039] This invention optimizes the combination of dianhydride monomers and diamine monomers, enabling the synthesized polyimide to dissolve in polar solvents at room temperature. This simplifies the processing technology, avoids the drawbacks of traditional polyimides requiring high-temperature and high-pressure molding, and thus improves processing performance.

[0040] By selecting monomers containing fluorine or alicyclic structures, the formation of charge transfer complexes between traditional PI molecular chains is effectively suppressed, making the material colorless or light-colored and transparent. This solves the problem of traditional polyimide having dark color and low transparency, and expands its application potential in flexible optoelectronic devices. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 Infrared spectra of the thermoplastic polyimide elastomers prepared in Examples 1-6;

[0043] Figure 2 Stress-strain curves of the thermoplastic polyimide elastomers prepared in Examples 1-6 and some commercially available elastomers are shown.

[0044] Figure 3 Thermogravimetric analysis (TGA) curves of the thermoplastic polyimide elastomers prepared in Examples 1-6 and some commercially available elastomers;

[0045] Figure 4 Differential scanning calorimetry (DSC) curves of the thermoplastic polyimide elastomers prepared in Examples 1-6;

[0046] Figure 5 The transmittance curves are for the thermoplastic polyimide elastomers prepared in Examples 1-6;

[0047] Figure 6 Atomic force microscopy (AFM) phase diagram of the thermoplastic polyimide elastomer prepared in Example 1. Detailed Implementation

[0048] The present invention will be further illustrated below with specific examples. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0049] Source of raw materials

[0050] ODA, 6FDA: Tianjin Zhongtai Materials Technology Co., Ltd.

[0051] TPDH: Adamas

[0052] NMP: General reagent

[0053] GBL: Sinopharm Chemical Reagent Co., Ltd.

[0054] P1000: Suzhou Xiangyuan New Materials Co., Ltd.

[0055] PEBA, brand name Arkema PEBAX 2533SA01MED

[0056] SEBS, brand name Kraton G1633

[0057] TPU, brand name BASF 1185A

[0058] PDMS, brand name SYLGARD 184

[0059] Test method:

[0060] Tensile testing: Tensile tests were performed on the samples according to GB / T 30776-2014, "Test Methods for Tensile Strength and Elongation at Break of Adhesive Tapes". The prepared thermoplastic polyimide elastomer was dissolved in DMAC and then cast. The casting was heated in an 80℃ forced-air oven to obtain a film of uniform thickness. Tensile strips of 4cm × 1cm were cut and tested using a universal testing machine.

[0061] Glass transition temperature: The glass transition temperature of thermoplastic polyimide elastomers was tested according to GB / T 22232-2008 Determination of thermal stability of chemical substances by differential scanning calorimetry.

[0062] Thermal decomposition temperature: The thermal decomposition temperature of thermoplastic polyimide elastomers was tested according to GB / T 33047.1-2016 Plastics Polymers Thermogravimetric Method (TG) Part 1: General Rules. A thermogravimetric analyzer (NETZSCH TG209F1Libra) was used to test the thermal decomposition temperature, with a test range of 30-800℃ and a heating rate of 10℃ / min.

[0063] Atomic force microscopy: Non-contact atomic force microscopy (AFM) was used to observe thermoplastic polyimide elastomer films with a thickness between 0.1 and 1 cm and a surface roughness not exceeding 5 μm.

[0064] Infrared spectroscopy test: The infrared spectrum of the sample was recorded using a Fourier transform infrared spectrometer (Thermo Fisher Scientific Nicolet iS50 FT-IR), with a wavelength scanning range of 650-4000 nm.

[0065] Transmittance Test: The transmittance of the thermoplastic polyimide elastomer film was tested using a UV-Vis spectrophotometer (Shimadzu UV-3600). The film thickness was controlled at 60-90 μm, and the test wavelength range was 300-800 nm. The transmittance of the film at 550 nm (T) was used as the metric. 550 (This is used as its visible light transmittance performance data.)

[0066] Solubility test: Dissolve 0.1g of thermoplastic polyimide elastomer in 0.9g of solvent (10wt% solids content), then stir for 24h and measure the solubility. Solubility indicates no phase separation, precipitation, or gel formation, while insoluble indicates that the resin does not dissolve and remains unchanged.

[0067] The technical solution of the present invention will be described in detail below with reference to specific embodiments. In the following embodiments, unless otherwise specified, the reagents, materials and equipment used can be purchased commercially, prepared by conventional methods, or commonly used in the industry.

[0068] Example 1:

[0069] Under argon protection, 2 mmol of rigid diamine ODA, 8 mmol of flexible diamine P1000, and 24 g of GBL were added to a three-necked flask. The mixture was mechanically stirred at 0 °C until the monomers were completely dissolved. Then, 10.5 mmol of dianhydride monomer 6FDA and 11 g of GBL were added, and the mixture was mechanically stirred at 0 °C for 12 h to obtain a PAA solution. Then, 10 ml of toluene and 0.15 g of isoquinoline were added. A water separator and a spherical condenser were installed on the three-necked flask containing the PAA solution. The spherical condenser was connected to refluxed -60 °C cold trap liquid. Argon gas was kept flowing through the flask, and the mixture was transferred to a 160 °C oil bath. The reaction was carried out for 8 h, and then the temperature was raised to 180 °C. After 2 h of reaction, the crude product was obtained.

[0070] The crude product was poured into methanol to precipitate polyimide. The product was then dried in a vacuum oven at -1.0 kPa and 80°C for 24 hours to obtain a thermoplastic polyimide elastomer sample.

[0071] Example 2:

[0072] The ratio of ODA to P1000 in Example 1 was adjusted to 3:7, while other conditions and parameters remained the same as in Example 1, to prepare a thermoplastic polyimide elastomer.

[0073] Example 3:

[0074] The solvent GBL in Example 1 was changed to NMP, while other conditions and parameters remained the same as in Example 1, and thermoplastic polyimide elastomer was prepared.

[0075] Example 4:

[0076] In Example 2, the solvent GBL was changed to NMP, while other conditions and parameters remained the same as in Example 2, and a thermoplastic polyimide elastomer was prepared.

[0077] Example 5:

[0078] In Example 1, 6FDA was changed to α-BPDA, ODA was changed to TPDH, and other conditions and parameters remained the same as in Example 1, thus preparing a thermoplastic polyimide elastomer.

[0079] Example 6:

[0080] In Example 1, ODA was changed to TPDH, while other conditions and parameters remained the same as in Example 1, and thermoplastic polyimide elastomer was prepared.

[0081] Comparative Example 1:

[0082] The ratio of ODA to P1000 in Example 1 was adjusted to 1:9, while other conditions and parameters remained the same as in Example 1, to prepare a thermoplastic polyimide elastomer.

[0083] Comparative Example 2:

[0084] The ratio of ODA to P1000 in Example 1 was adjusted to 4:6, while other conditions and parameters remained the same as in Example 1, to prepare a thermoplastic polyimide elastomer.

[0085] Comparative Example 3: In Example 1, 6FDA was changed to BPDA, P1000 was changed to polyetheramine D2000, and other conditions and parameters were kept the same as in Example 1 to prepare polyimide elastomer.

[0086] The monomers, monomer ratios, and solvents used in all examples and comparative examples are summarized in Table 1.

[0087] Table 1

[0088] Dihydride monomer rigid diamine monomers Flexible diamine monomer Monomer ratio solvent Example 1 6FDA ODA P1000 2：8 GBL Example 2 6FDA ODA P1000 3：7 GBL Example 3 6FDA ODA P1000 2：8 NMP Example 4 6FDA ODA P1000 3：7 NMP Example 5 α-BPDA TPDH P1000 2：8 GBL Example 6 6FDA TPDH P1000 2：8 GBL Comparative Example 1 6FDA ODA P1000 1：9 GBL Comparative Example 2 6FDA ODA P1000 4：6 GBL Comparative Example 3 BPDA ODA D2000 2：8 GBL

[0089] Solubility tests were conducted on the polyimide elastomer samples prepared in the examples and comparative examples, and the results are shown in Table 2. The polyimide backbone prepared using the dianhydride monomer BPDA in Comparative Example 3 exhibited high regularity, significant intermolecular / intramolecular charge transfer, and easy chain stacking and crystallization. Strong inter-chain π-π interactions prevented organic solvents from penetrating between the chains, thus rendering it insoluble in most organic solvents. This demonstrates that a reasonable combination of diamine and dianhydride monomers is a key factor in the preparation of thermoplastic polyimides. Furthermore, the excessive proportion of flexible diamine monomer in Comparative Example 1 resulted in the inability to reform a film with a fixed shape after dissolution, leading to excessively low tensile strength. The excessive proportion of rigid diamine monomer in Comparative Example 2 resulted in a hard and brittle film with almost no elasticity; therefore, no further performance tests were conducted.

[0090] Table 2

[0091] sample DMF DMAC DMSO NMP GBL THF m-Cresol concentrated sulfuric acid Example 1 soluble soluble soluble soluble soluble soluble soluble soluble Example 2 soluble soluble soluble soluble soluble soluble soluble soluble Example 3 soluble soluble soluble soluble soluble soluble soluble soluble Example 4 soluble soluble soluble soluble soluble soluble soluble soluble Example 5 soluble soluble soluble soluble soluble soluble soluble soluble Example 6 soluble soluble soluble soluble soluble soluble soluble soluble Comparative Example 1 soluble soluble soluble soluble soluble soluble soluble soluble Comparative Example 2 soluble soluble soluble soluble soluble soluble soluble soluble Comparative Example 3 Insoluble Insoluble Insoluble Insoluble Insoluble Insoluble Insoluble Insoluble

[0092] Figure 1 Infrared spectra of the polyimide elastomer samples prepared in Examples 1-6. It can be seen that all samples in the examples exhibit characteristic peaks of polyimide, such as 1780 cm⁻¹. -1 The peak represents the C=O symmetric stretching vibration of the imide ring, at 1722 cm⁻¹. -1 The peak is the C=O asymmetric stretching vibration peak of the imide ring, at 1367 cm⁻¹. -1 The peaks were CNC stretching vibrations of the imide ring, and no characteristic peaks of polyamic acid groups were observed.

[0093] Figure 2 Tensile tests were conducted on the thermoplastic polyimide elastomers prepared in Examples 1-6, as well as commercially available elastomers SEBS, TPU, and PDMS. It can be seen that the elastomer prepared in Example 2 has a tensile strength of up to 39 MPa, significantly higher than the other three commercially available elastomers. Although its elongation at break (992%) is lower than that of commercially available SEBS (~1500%) and TPU (~1000%), it far surpasses both in tensile strength and toughness. Specific tensile test results are shown in Table 3.

[0094] Table 3

[0095]

[0096]

[0097] Figure 3 The thermogravimetric curves of the thermoplastic polyimide elastomers prepared in Examples 1-6 in a nitrogen atmosphere, with thermal decomposition temperature T. d,5％ All of them maintain high thermal stability at temperatures above 360℃.

[0098] Figure 4The DSC curves obtained by differential scanning calorimetry testing of the thermoplastic polyimide elastomers prepared in Examples 1-6 show that their glass transition temperatures in a nitrogen atmosphere are between -70 and -60°C, and there are no significant melting or crystallization peaks, reflecting the excellent heat resistance and amorphous properties of the thermoplastic polyimide elastomers in an inert atmosphere.

[0099] Figure 5 The transmittance curves are for the thermoplastic polyimide elastomer films prepared in Examples 1-6, with Example 5 exhibiting excellent transmittance in the visible light wavelength range.

[0100] The test data above are summarized in Table 4.

[0101] Table 4

[0102] sample Glass transition temperature (°C) <![CDATA[Thermal decomposition temperature T d,5％ (°C)]]> <![CDATA[Light transmittance T 550 (%)]]> Example 1 -64.23 372 89.96 Example 2 -68.93 368 79.47 Example 3 -66.35 248 87.24 Example 4 -69.32 373 89.08 Example 5 -67.15 364 89.58 Example 6 -67.08 363 87.07

[0103] Figure 6 The AFM phase diagram of Example 1 shows a clear microphase separation structure: the bright areas in the image correspond to rigid imide hard segments with high modulus, while the dark areas correspond to flexible polyether soft segments with low modulus. This nanoscale phase separation of hard / soft segments originates from the thermodynamic incompatibility between the rigid cyclic imide structure and the flexible polyether segments in the molecular chain—the rigid imide segments form a physical cross-linked network through intermolecular charge transfer and π-π stacking, forming a high-modulus "island" hard phase region; the flexible segments form a continuous phase through free segment movement, constituting a low-modulus soft phase matrix. The same morphology was also found in other examples.

[0104] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.

Claims

1. A method for preparing a high-strength and tough thermoplastic polyimide elastomer, characterized in that, Includes the following steps: Under a protective atmosphere, dianhydride monomers, rigid diamine monomers, flexible diamine monomers and solvents are mixed and polymerized to produce polyamic acid. A catalyst is then added for imidization to obtain thermoplastic polyimide elastomers. Wherein, the dianhydride monomer is hexafluorodianhydride, the rigid diamine monomer is 4,4'-diaminodiphenyl ether, the flexible diamine monomer is poly-1,4-butanediol bis(4-aminobenzoate), the solvent is N-methylpyrrolidone or 1,4-butyrolactone, the molar ratio of rigid diamine monomer to flexible diamine monomer is 2:8~3:7; the monomer solid content is 5%~100%, wherein the monomer is the total amount of dianhydride monomer, rigid diamine monomer and flexible diamine monomer; the molar ratio of dianhydride monomer to diamine monomer is 10.1~10.5:10, wherein the diamine monomer is the total amount of rigid diamine monomer and flexible diamine monomer; The general structural formula of thermoplastic polyimide elastomers is as follows: ； Wherein, the structural formula of R1 is The structural formula of R2 is The structural formula of R3 is The value of n1 is in the range of 5-13, and the value of q+p is in the range of 2-15, and neither q nor p is 0; The imidization is thermal imidization, in which a catalyst and a dehydrating agent are added. The catalyst is isoquinoline; the dehydrating agent is toluene; the catalyst accounts for 0.5-2% of the total mass of the monomer; the thermal imidization temperature range is 120-200°C, and the thermal imidization time is 4-24 h.

2. The preparation method according to claim 1, characterized in that, The polymerization reaction temperature is -20~120 °C, and the polymerization reaction time is 0.5~24 h.

3. A high-strength and tough thermoplastic polyimide elastomer prepared by the method according to any one of claims 1 to 2.

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