Thermoplastic polyimide polyether sulfone alloy and method for preparing the same

Abstract

The application provides a thermoplastic polyimide polyether sulfone alloy and a preparation method thereof, and relates to the technical field of high polymer materials.The high polymer alloy can significantly improve the compatibility of a blending system by introducing similar structural units.When both phases in the blending system contain ether sulfone structures, the interface energy is reduced, and the adhesion between phases is enhanced; the structural similarity at the molecular level can promote interface diffusion, form a thick interface transition layer, effectively transfer stress, and the obtained alloy has a T g Instead of two independent values, a new T g Temperature, which can prove that the two high polymer materials in the application are fused at the molecular chain level, rather than simply mixed.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a thermoplastic polyimide polyethersulfone alloy and its preparation method. Background Technology

[0002] Polyethersulfone (PES) has become one of the most important specialty engineering plastics due to its three core advantages: high temperature resistance, dimensional stability, and flame retardancy and safety. It is particularly suitable for medical devices, electronic insulation, and high-temperature fluid components. Thanks to its excellent solubility and processing properties, it can be combined with a variety of other materials, including polyimide (PI), to form composite materials or alloys.

[0003] Compared to traditional thermosetting polyimides (PIs) or other thermoplastic polyimides (TPIs), bisphenol A-type TPIs exhibit significantly improved solubility, being soluble in highly polar solvents (such as DMF, NMP, and DMAC) and low-boiling-point solvents (such as THF). This characteristic greatly broadens its solution processing window. Simultaneously, it possesses a good balance of mechanical properties. Bisphenol A-type TPIs retain the inherent high strength and high modulus characteristics of the polyimide family, with tensile strength typically ranging from 90 to 115 MPa and tensile modulus between 2.8 and 3.5 GPa, meeting the requirements of most structural applications. The flexible ether bond structure of the bisphenol A unit endows the material with superior toughness compared to other high-rigidity PIs, making it an ideal material compatible with PES.

[0004] In view of this, it is necessary to design an improved thermoplastic polyimide polyethersulfone alloy and its preparation method to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a thermoplastic polyimide polyethersulfone alloy and its preparation method.

[0006] To achieve the above-mentioned objective, this invention provides a method for preparing a thermoplastic polyimide polyethersulfone alloy, characterized by comprising the following steps:

[0007] S1. Under an inert gas atmosphere, the solvent, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, and catalyst are mixed and thoroughly mixed at 0-10℃. Then, bisphenol A dianhydride is added and the mixture is reacted at 0-10℃ for 4-8 hours.

[0008] S2. Add toluene to the reaction system of step S1, react at 135℃ for 2-3 hours, and then react at 180℃ for 6-12 hours; after the reaction is completed, TPI powder is obtained.

[0009] S3. After mixing the TPI powder obtained in step S2 with polyethersulfone evenly, a thermoplastic polyimide polyethersulfone alloy is obtained.

[0010] Preferably, in step S3, the mass ratio of TPI powder to polyethersulfone is (1-9):(1-9).

[0011] Preferably, the mass ratio of TPI powder to polyethersulfone is 1:9, at which point the resulting thermoplastic polyimide-polyethersulfone alloy has a T... g It is 191.7℃.

[0012] Preferably, the mass ratio of TPI powder to polyethersulfone is 9:1, at which point the resulting thermoplastic polyimide-polyethersulfone alloy has a T... g It is 222.8℃.

[0013] Preferably, in step S1, the molar ratio of 4,4'-bis(3-aminophenoxy)diphenyl sulfone to bisphenol A dianhydride is 100:101-100:105, and the ratio of the total mass of 4,4'-bis(3-aminophenoxy)diphenyl sulfone and bisphenol A dianhydride to the mass of the solvent is 10:90-30:70.

[0014] Preferably, in step S1, the catalyst is isoquinoline, and its amount is 0.5-3% of the amount of bisphenol A dianhydride.

[0015] Preferably, in step S1, the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and m-methylphenol.

[0016] Preferably, in step S1, the inert gas is nitrogen or argon.

[0017] The beneficial effects of this invention are:

[0018] 1. The method for preparing thermoplastic polyimide-polyethersulfone alloy provided by this invention achieves multi-level integration and performance optimization of TPI and PES materials through a combination of molecular-level structural hybrid design and macro-scale blending modification. By introducing ethersulfone structural units into the TPI molecular chain, the high-temperature resistance of polyimide and the excellent processability of polyethersulfone can be combined. The sulfone groups in the ethersulfone structure can improve the rigidity of the molecular chain, while the ether bonds provide appropriate chain segment flexibility and improve melt flowability. At the same time, the bisphenol A structure is retained, utilizing its function of improving solubility and toughness to form a "rigid and flexible" molecular structure.

[0019] 2. The thermoplastic polyimide-polyethersulfone alloy provided by this invention can significantly improve the compatibility of the blend system by introducing similar structural units. When both phases in the blend system contain ethersulfone structures, the interfacial energy decreases and the interphase adhesion is enhanced; the molecular-level structural similarity can promote interfacial diffusion, forming a thick interfacial transition layer, effectively transferring stress, and the resulting alloy's T g They are no longer two separate values, but have been merged into a new T.g Temperature can prove that the two polymer materials in this invention have undergone molecular chain-level fusion, rather than simple mixing. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be described in detail below with reference to specific embodiments.

[0021] It should also be noted that, in order to avoid obscuring the present invention with unnecessary details, only the structures and / or processing steps closely related to the present invention are shown in the text, while other details that are not closely related to the present invention are omitted.

[0022] Additionally, it should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0023] This invention provides a method for preparing a thermoplastic polyimide polyethersulfone alloy, comprising the following steps:

[0024] S1. Under an inert gas atmosphere, the solvent, 4,4'-bis(3-aminophenoxy)diphenyl sulfone (m-BAPS) and catalyst are mixed and thoroughly mixed at 0-10℃. After uniform mixing, bisphenol A dianhydride (BPADA) is added and the mixture is reacted at 0-10℃ for 4-8 hours.

[0025] S2. Add toluene to the reaction system of step S1, react at 135℃ for 2-3 hours, and then react at 180℃ for 6-12 hours. After the reaction is completed, let the system cool to room temperature, pour the solution obtained from the reaction into anhydrous ethanol, wash and dry to obtain TPI powder.

[0026] S3. After mixing the TPI powder obtained in step S2 with polyethersulfone (PES) in a certain proportion, a thermoplastic polyimide polyethersulfone alloy is obtained.

[0027] In some embodiments, the inert gas is nitrogen or argon.

[0028] In some embodiments, in step S1, the solvent is one or more of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAC), N-methylpyrrolidone (NMP), and m-cresol.

[0029] In some embodiments, in step S1, the catalyst is isoquinoline, and its amount is 0.5-3% of the amount of BPADA.

[0030] In some embodiments, in step S1, the molar ratio of m-BAPS to BPADA is 100:101-100:105, and the ratio of the total mass of m-BAPS and BPADA to the mass of the solvent is 10:90-30:70.

[0031] In some embodiments, in step S3, the mass ratio of TPI powder to PES is (1-9):(1-9).

[0032] The thermoplastic polyimide-polyethersulfone alloy and its preparation method proposed in this invention will be further illustrated below with reference to specific embodiments:

[0033] Example 1

[0034] S1. Under an inert gas atmosphere, 387g of DMF (analytical grade), 0.1mol of m-BAPS, and isoquinoline were mixed and thoroughly mixed at 0℃. After homogeneity, 0.103mol of BPADA was added, and the mixture was reacted at 0℃ for 6h. The amount of isoquinoline was 1% of the amount of BPADA.

[0035] S2. Add toluene (analytical grade) to the reaction system of step S1, react at 135℃ for 2-3 hours, and then react at 180℃ for 6-12 hours. After the reaction is completed, let the system cool to room temperature, pour the solution obtained from the reaction into anhydrous ethanol, wash and dry to obtain TPI powder.

[0036] S3. Mix the TPI powder obtained in step S2 with PES at a mass ratio of 1:9, dissolve in DMF at room temperature, and stir until the material is fully solvated and the solution is stable and homogeneous. Finally, remove the solvent and dry to obtain a thermoplastic polyimide polyethersulfone alloy. It should be noted that toluene in step S2 is used as a dehydrating agent to remove water from the system. The addition of DMF in step S3 is only used to mix and dissolve the TPI powder with PES; as long as this purpose is achieved, the amount of toluene and DMF is not limited. Furthermore, all reagents used in the embodiments of this invention can be obtained commercially.

[0037] Example 2

[0038] The only difference between Example 2 and Example 1 is that in step S3, the mass ratio of TPI powder to PES is 5:5. The other experimental parameters are the same as in Example 1 and will not be repeated here.

[0039] Example 3

[0040] The only difference between Example 3 and Example 1 is that in step S3, the mass ratio of TPI powder to PES is 9:1. The other experimental parameters are the same as in Example 1 and will not be repeated here.

[0041] Comparative Example 1

[0042] The difference between Comparative Example 1 and Example 1 is that TPI was prepared using m-phenylenediamine (m-PDA) and 4,4'-bis(4-aminophenoxy)diphenyl ether (PBADA). The remaining experimental parameters were the same as in Example 1 and will not be repeated here.

[0043] Comparative Example 2

[0044] The difference between Comparative Example 2 and Example 1 is that TPI was prepared using m-phenylenediamine (m-PDA) and 4,4'-bis(4-aminophenoxy)diphenyl ether (PBADA), and the mass ratio of TPI powder to PES was 5:5. The remaining experimental parameters were the same as in Example 1.

[0045] The thermal performance data of the thermoplastic polyimide polyethersulfone alloys prepared in Examples 1-3 and Comparative Examples 1-2 are shown in Table 1. The thermal performance data of the alloys prepared in Examples 1-3 are compared with those in Examples 1-3. g The data shows that under conditions of 10% PES content or 10% TPI content, the T values ​​of the two materials are... g Complete fusion, with values ​​close to and greater than 90% of the components, is due to the similar molecular chain structures of the two materials, achieving uniform mixing at the molecular chain level. (T) g The numerical values ​​all show an increase because this uniform mixing at the molecular chain level hinders the original molecular chain movement, causing the temperature of the amorphous portion of the polymer to rise from a frozen state to a thawed state. However, this mixing is not infinitely miscible; in Example 2 (i.e., the mass ratio of PES to TPI is 1:1), the alloy exhibited the common double-T phenomenon. g And two Ts g The values ​​are all greater than the corresponding values ​​for pure resin, T g The increase in [amount] proves that uniform mixing at the molecular chain level was still achieved at this ratio, but [the following is unclear due to incomplete sentence fragment: "double T"] g The emergence of this phenomenon proves that this mixture is a mixture in which one material can partially dissolve in another, rather than two materials being infinitely miscible.

[0046] The molecular structure of the synthesized TPI in Comparative Examples 1-2 differs from that of the TPI in the examples in that it does not contain an ether sulfone group. Therefore, the mixture of the two materials does not produce TPI. g Fusion or T g The phenomenon of increased T in alloys d5% The lower thermal stability is due to the fact that the TPI prepared by m-PDA+PBADA is not as good as the TPI prepared by m-BAPS+PBADA.

[0047] Table 1. Thermal properties of the thermoplastic polyimide-polyethersulfone alloys prepared in Examples 1 to 3 and Comparative Examples 1 to 2

[0048]

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing a thermoplastic polyimide-polyethersulfone alloy, characterized in that, Includes the following steps: S1. Under an inert gas atmosphere, the solvent, 4,4'-bis(3-aminophenoxy)diphenyl sulfone, and catalyst are mixed and thoroughly mixed at 0-10℃. Then, bisphenol A dianhydride is added, and the mixture is reacted at 0-10℃ for 4-8 hours. The molar ratio of 4,4'-bis(3-aminophenoxy)diphenyl sulfone to bisphenol A dianhydride is 100:101-100:105, and the ratio of the total mass of 4,4'-bis(3-aminophenoxy)diphenyl sulfone and bisphenol A dianhydride to the mass of the solvent is 10:90-30:

70. S2. Add toluene to the reaction system of step S1, react at 135℃ for 2-3 hours, and then react at 180℃ for 6-12 hours; after the reaction is completed, TPI powder is obtained. S3. After uniformly mixing the TPI powder obtained in step S2 with polyethersulfone, a thermoplastic polyimide-polyethersulfone alloy is obtained; the mass ratio of TPI powder to polyethersulfone is 1:9 or 9:

1.

2. The preparation method according to claim 1, characterized in that, In step S1, the catalyst is isoquinoline, and its amount is 0.5-3% of the amount of bisphenol A dianhydride.

3. The preparation method according to claim 1, characterized in that, In step S1, the solvent is one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, and m-methylphenol.

4. The preparation method according to claim 1, characterized in that, In step S1, the inert gas is nitrogen or argon.

5. A thermoplastic polyimide-polyethersulfone alloy prepared by the preparation method according to any one of claims 1-4, characterized in that, The T of the thermoplastic polyimide polyethersulfone alloy g It is 191.7℃.

6. A thermoplastic polyimide-polyethersulfone alloy prepared by the preparation method according to any one of claims 1-4, characterized in that, The T of the thermoplastic polyimide polyethersulfone alloy g It is 222.8℃.

Images