Crosslinkable polymer and application thereof

Abstract

The invention provides a crosslinkable polymer and application thereof, the crosslinkable polymer has a structure as shown in formula I. Through the structural design of a polymer skeleton constructed by aromatic rings with a specific structure, number and connection mode, the crosslinkable polymer has a proper HOMO energy level, high hole mobility and high triplet state energy level, and the molecular weight of the crosslinkable polymer is increased. As a hole transport material, the compound can significantly improve the luminous efficiency and the working life of an organic electroluminescent device, and reduce the voltage. The cross-linkable polymer can meet the requirements of a solution processing method, secondary cross-linking reaction can occur after film forming, a polymer film subjected to secondary cross-linking forms a three-dimensional network structure, the solubility is reduced, excellent hole transport performance is maintained, meanwhile, high solvent resistance is achieved, various solvent requirements of a next functional layer can be met, and the cross-linkable polymer can be widely applied to the field of organic light emitting devices. Therefore, the problem of mutual dissolution between the hole transport layer and the adjacent layer is solved, and the device is endowed with more excellent comprehensive performance.

Description

Technical Field

[0001] This invention belongs to the field of organic electroluminescence technology, specifically relating to a crosslinkable polymer and its applications. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are a type of device with a multifunctional layer structure, including positive and negative electrode layers and an organic functional material layer sandwiched between the two electrode layers. When a voltage is applied to the electrodes of an OLED device, positive charges are injected from the positive electrode and negative charges are injected from the negative electrode. Under the influence of an electric field, the positive and negative charges migrate, meet, and recombine in the organic layer, exciting the dye to emit light. Due to its advantages such as high brightness, fast response, wide viewing angle, simple manufacturing process, and flexibility, OLED devices have attracted much attention in the fields of new display technology and new lighting technology. Currently, this technology has been widely used in display panels for new lighting fixtures, smartphones, and tablets, and will further expand into large-size display products such as televisions. It is a rapidly developing and technologically demanding new display technology.

[0003] Organic functional materials are the core of OLED devices. Common organic functional materials include: hole injection materials, hole transport materials, hole blocking materials, electron injection materials, electron transport materials, electron blocking materials, luminescent host materials, and luminescent guest materials (dyes). The hole transport layer is one of the most important functional layers in OLED devices, and using high-performance hole transport materials is one of the main methods to improve device performance.

[0004] Currently, vacuum evaporation is the primary method for fabricating OLED devices. This method is suitable for preparing small-sized thin films and is the main fabrication process for commercial OLEDs. However, small-molecule hole transport materials are prone to crystallization during device operation, leading to degradation of hole transport performance and overall device performance. Furthermore, vacuum evaporation has low material utilization, resulting in high product prices. Solution processing offers advantages in improving material utilization, simplifying device fabrication processes, and fabricating large-area devices, making it highly commercially valuable. However, in solution processing, adjacent organic materials have similar solubility, which can cause the upper solution to dissolve the lower, already formed film material, resulting in interlayer miscibility. This miscibility leads to disordered functional layer interfaces, affecting carrier transport, disrupting equilibrium, and causing a significant deterioration in device performance. To avoid this problem, a common approach is to select orthogonal solvents, dissolving the upper and lower layers in immiscible solvents to prevent miscibility. However, choosing such orthogonal solvents is difficult and limits the material's structural design. Another approach is to introduce cross-linking groups into the original material, forming a three-dimensional network structure through secondary cross-linking. After cross-linking, the material's molecular weight increases, its stability is enhanced, and it exhibits good solvent resistance, effectively solving the interlayer miscibility problem in solution-based OLED device fabrication. This also preserves the original material's advantages, such as energy levels and mobility, and makes it more adaptable to solution-based or inkjet printing methods. However, current hole transport materials suitable for solution processing generally suffer from low hole mobility and energy level mismatch, leading to poor device performance and limiting their commercial application. Therefore, developing hole transport materials with high hole mobility and suitable energy levels to meet the development needs of solution-based OLED device fabrication is an urgent problem to be solved in this field. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a crosslinkable polymer and its applications. The repeating unit of the crosslinkable polymer contains two binatrimethylenetriamine junction structures. By constructing a polymer backbone through a specific structure and number of aromatic rings, the crosslinkable polymer possesses suitable HOMO energy levels, high hole mobility, and high triplet energy levels. It is suitable as a hole transport material, effectively improving the luminescence performance and lifetime of organic electroluminescent devices. Furthermore, the crosslinkable polymer can solve the problem of mutual solubility between the hole transport layer and adjacent layers through crosslinking reactions, resulting in devices with excellent overall performance. This has significant value for the development of solution-based OLED device fabrication.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a crosslinkable polymer having a structure as shown in Formula I:

[0008]

[0009] In Formula I, L is selected from any one of a single bond, a substituted or unsubstituted C6-C30 arylene, or a substituted or unsubstituted C3-C30 heteroarylene; when L is a single bond, it means that the N atom of the aromatic amine is directly connected to the naphthalene ring structure in Formula I through a single bond.

[0010] In Formula I, Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups.

[0011] In Formula I, R1 is independently selected from any one of the following: halogen, crosslinkable group, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 alkylthio, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl.

[0012] The substituents described in L, Ar1, Ar2, and R1 are each independently selected from any one of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C30 straight-chain or branched alkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, C3-C30 cycloalkyl groups, C2-C30 heterocycloalkyl groups, unsubstituted or R'-substituted C6-C30 aryl groups, unsubstituted or R'-substituted C3-C30 heteroaryl groups, unsubstituted or R'-substituted C3-C30 arylamino groups, and unsubstituted or R'-substituted C3-C30 heteroarylamino groups.

[0013] In this invention, the "substituted or unsubstituted" group can be substituted with one substituent or multiple substituents. When there are multiple substituents (at least two), they can be the same or different substituents; the same expression used below has the same meaning. Unless otherwise specified, the selection range of substituents is as shown above and will not be repeated.

[0014] R' is independently selected from any one or a combination of at least two of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C20 straight-chain or branched alkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, C3-C20 cycloalkyl groups, C2-C20 heterocycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C3-C30 arylamino groups, and C3-C30 heteroarylamino groups.

[0015] In this invention, the "unsubstituted or R'-substituted" group can be substituted with one R' or multiple R's. When there are multiple (at least two) R's, the multiple R's can be the same or different groups. The same expressions used below have the same meaning. Unless otherwise specified, the selection range of R's is as shown above and will not be repeated.

[0016] In Formula I, Ar1, Ar2, and R1 contain at least one crosslinkable group.

[0017] It should be noted that in the crosslinkable polymer of the present invention, the repeating unit shown in Formula I contains at least one crosslinkable group, that is, the number of crosslinkable groups in the repeating unit is ≥1, and can be 1, 2, 3, 4, 5, 6, 7, 8, etc. When the number of crosslinkable groups is ≥2, the multiple crosslinkable groups can be the same or different. The crosslinkable group can be R1, a substituent on R1, or a substituent on Ar1 and / or Ar2.

[0018] The crosslinkable group is a group containing at least one of the following: C=C unsaturated bond, C≡C unsaturated bond, oxocyclic ring, azide group, hydroxyl group, ester group, cyanate group, isocyanate group, di(alkyl)amino group, siloxane group, and alkylsilyl group.

[0019] In formula I, n represents The number of integers is selected from 1 to 5, for example, it can be 1, 2, 3, 4 or 5; when n≥2, multiple These can be the same or different groups.

[0020] In Formula I, m represents the number of substituents R1 on the benzene ring, each independently selected from an integer between 0 and 4, for example, 0, 1, 2, 3 or 4; when m = 0, it means that the benzene ring does not contain any substituents and is entirely hydrogen; when m ≥ 2, multiple R1s are the same or different groups.

[0021] In Formula I, x represents the degree of polymerization of the crosslinkable polymer, and x ≥ 1.

[0022] Each repeating unit of the crosslinkable polymer provided by the present invention contains a triarylamine system with two binaphthylamine structures, which improves the hole mobility of the crosslinkable polymer; meanwhile, the 1-substituted binaphthyl has steric hindrance, which to a certain extent increases the triplet energy level of the whole molecule; the two triarylamine structures are connected by a polyaromatic ring with a specific structure and number, further expanding the conjugated system of the molecule, facilitating electron transition and increasing the mobility. Through the structural design of the polymer backbone, the crosslinkable polymer of the present invention has a suitable HOMO energy level, a high hole mobility and a high triplet energy level. As a hole transport material, it can significantly improve the luminous efficiency and working life of the organic light-emitting device and reduce the voltage. The crosslinkable polymer can meet the requirements of the solution processing method, and can undergo a secondary crosslinking reaction after film formation. The polymer film after secondary crosslinking forms a three-dimensional network structure, the molecular weight is further increased, the solubility is reduced, it has strong solvent resistance, and maintains excellent hole transport performance, and can meet the solvent requirements of the next functional layer, thus solving the problem of mutual solubility between the hole transport layer and the adjacent layer, and endowing the device with more excellent comprehensive performance.

[0023] It should be noted that in the present invention, for the convenience of description, the possible functions of each group / feature are described separately, but this does not mean that these groups / features act independently. In fact, the reason for obtaining good performance is essentially the optimized combination of the whole molecule, which is the result of the synergistic effect between each group, rather than the effect of a single group.

[0024] The following are the preferred technical solutions of the present invention, but not a limitation to the technical solutions provided by the present invention. Through the following preferred technical solutions, the purpose and beneficial effects of the present invention can be better achieved.

[0025] In the present invention, for the description of chemical elements, unless otherwise specified, the concept of isotopes with the same chemical properties is included. For example, hydrogen (H) includes 1 H (protium), 2 H (deuterium, D), 3 H (tritium, T), etc.; carbon (C) includes 12 C, 13 C, etc.

[0026] In the present invention, unless otherwise specified, the heteroatoms in the heteroaryl are selected from N, O, S, P, B, Si or Se, preferably N, O or S. The heteroatoms in the heterocyclic alkyl are selected from N, O, S, P, B, Si or Se, preferably N, O or S.

[0027] In the present invention, the expression of the ring structure with a "—" drawn across it indicates that the connection site is at any position on the ring structure where bonding can occur.

[0028] In this invention, "-*" and "*" both represent the linking site of a group.

[0029] In this invention, the expression Ca-Cb represents that the group has ab carbon atoms. Unless otherwise specified, the number of carbon atoms does not include the number of carbon atoms of the substituents.

[0030] In this invention, "each independently" means that when there are multiple subjects, they can be the same or different from each other.

[0031] In this invention, the halogen can be fluorine, chlorine, bromine, or iodine. The same descriptions used below have the same meaning.

[0032] C6-C30 can all be C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0033] C3-C30 can all be C3, C4, C5, C6, C9, C10, C12, C14, C16, C18, C20, C22, C24, C26 or C28, etc.

[0034] C1-C30 can all be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C22, C24, C26 or C28, etc.

[0035] C2-C30 can all be C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C22, C24, C26 or C28, etc.

[0036] C1-C20 can all be C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C19, etc.

[0037] C2-C20 can all be C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C19, etc.

[0038] C3-C20 can all be C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18 or C19, etc.

[0039] In this invention, the C6-C30 aryl group, preferably C6-C25 aryl group, includes monocyclic aryl and fused-ring aryl groups; the monocyclic aryl group means that the group contains at least one phenyl group, and when it contains at least two phenyl groups, the phenyl groups are linked by a single bond, exemplarily including but not limited to: phenyl, biphenyl, terphenyl, tetraphenyl, etc.; the fused-ring aryl group means that the group contains at least two aromatic rings, and the aromatic rings share two adjacent carbon atoms. Mutually fused groups, exemplary examples, include but are not limited to: naphthyl, anthraceneyl, phenanthryl, indene, fluorenyl and their derivatives (9,9-dimethylfluorenyl, 9,9-diethylfluorenyl, 9,9-dipropylfluorenyl, 9,9-dibutylfluorenyl, 9,9-dipentylfluorenyl, 9,9-dihexylfluorenyl, 9,9-diphenylfluorenyl, 9,9-dinaphthylfluorenyl, spirodifluorenyl, benzo[a]fluorenyl, etc.), fluoranthyl, triphenylene, pyrene, perylene, Aryl, tetraphenyl, acenaphthyl, benzo[a]acenaphthyl, etc. It should be noted that monocyclic aryl and fused-ring aryl groups linked by single bonds also fall under the aryl group category, such as phenylnaphthyl, naphthylphenyl, binaphthyl, phenylnaphthylphenyl, etc.

[0040] The C3-C30 heteroaryl group, preferably C3-C20 heteroaryl group, includes monocyclic heteroaryl groups or fused-ring heteroaryl groups. A monocyclic heteroaryl group means that the molecule contains at least one heteroaryl group. When the molecule contains one heteroaryl group and other groups (such as aryl, heteroaryl, etc.), the heteroaryl group and other groups are connected by a single bond, exemplarily including but not limited to: pyridyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, furanyl, thiophene, pyrroleyl, bipyridyl, phenylpyridinyl, pyridylphenyl, etc. The term "fused-ring heteroaryl" refers to a molecule containing at least one aromatic heterocycle and one aromatic ring (aromatic heterocycle or aromatic ring), and the two share two adjacent atoms fused together in a group. Examples include, but are not limited to: quinolinyl, isoquinolinyl, quinoxolinyl, quinazolinyl, benzofuranyl, benzothiophenyl, isobenzofuranyl, isobenzothiophenyl, indolyl, dibenzofuranyl, dibenzothiophenyl, carbazoleyl and its derivatives (N-phenylcarbazoleyl, N-naphthylcarbazoleyl, benzocarbazoleyl, dibenzocarbazoleyl, indolocarbazoleyl, azacarbazoleyl, indocarbazoleyl, etc.), acridineyl, phenazinyl, phenothiazinyl, phenotoxazinyl, hydrogenated acridineyl, benzoxazoleyl, etc. It should be noted that heteroaryl groups connected by single bonds, as well as aryl groups connected by single bonds, also fall under the category of heteroaryl groups, such as phenyldibenzofuranyl, phenyldibenzothiophenyl, dibenzofuranylphenyl, dibenzothiophenylphenyl, phenylcarbazoyl, etc.

[0041] In this invention, the C6-C30 arylene is a divalent group obtained by removing one H atom from the aforementioned aryl group; the C3-C30 heteroarylene is a divalent group obtained by removing one H atom from the aforementioned heteroaryl group.

[0042] In this invention, a specific example of the C6-C30 arylamino group is a monovalent group obtained by substituting at least one hydrogen atom in -NH2 with the aforementioned aryl group. A specific example of the C3-C30 heteroarylamino group is a monovalent group obtained by substituting at least one hydrogen atom in -NH2 with the aforementioned heteroaryl group.

[0043] The C1-C30 straight-chain or branched alkyl groups, C1-C20 straight-chain or branched alkyl groups, preferably C1-C16 straight-chain or branched alkyl groups, and more preferably C1-C15 straight-chain or branched alkyl groups, are exemplary but not limited to: methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2-methylbutyl, n-pentyl, isopentyl, neopentyl, n-hexyl, neohexyl, 2-ethylhexyl, n-octyl, n-heptyl, n-nonyl, n-decyl, straight-chain or branched undecyl, straight-chain or branched dodecyl, straight-chain or branched tridecyl, straight-chain or branched tetradecyl, straight-chain or branched pentadecyl, straight-chain or branched hexadecyl, etc.

[0044] Specific examples of the C1-C30 alkoxy and C1-C20 alkoxy groups can be exemplified by the monovalent groups obtained by connecting the aforementioned straight-chain or branched alkyl groups to O. Specific examples of the C1-C30 alkylthio and C1-C20 alkylthio groups can be exemplified by the monovalent groups obtained by connecting the aforementioned straight-chain or branched alkyl groups to S.

[0045] The C3-C30 cycloalkyl, C3-C20 cycloalkyl, preferably C3-C10 cycloalkyl, includes monocycloalkyl or polycycloalkyl. Monocycloalkyl refers to an alkyl group containing a single ring structure, while polycycloalkyl refers to a structure formed by two or more cycloalkyl groups sharing one or more carbon atoms on a ring; exemplary examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and adamantyl.

[0046] Specific examples of the C2-C30 heterocyclic alkyl and C2-C20 heterocyclic alkyl groups can be given by forming a monovalent group in which one of the ring carbon atoms of the above-mentioned cycloalkyl group is replaced by a heteroatom, and the heteroatom is preferably N, O or S, etc.

[0047] Preferably, the crosslinkable polymer has a structure as shown in any one of Formula II-1, Formula II-2, or Formula II-3:

[0048]

[0049] Among them, L, Ar1, Ar2, R1, n and m have the same limited range as Equation I.

[0050] In this invention, the "crosslinkable group" refers to a group capable of undergoing an irreversible curing or polymerization reaction to form a non-reformable material (i.e., a thermosetting material). Crosslinking can typically be assisted by methods such as heating, UV irradiation, microwave irradiation, or X-ray irradiation. The crosslinkable group can be a group containing double bonds, triple bonds, precursors capable of forming double bonds in situ, or heterocyclic polymerization-capable groups. For example, it can be a group containing at least one of the following: C=C unsaturated bonds, C≡C unsaturated bonds, oxocyclic rings, azide groups, hydroxyl groups, ester groups, cyanate groups, isocyanate groups, di(alkyl)amino groups, siloxane groups, or alkylsilyl groups.

[0051] The crosslinkable groups include, but are not limited to: benzocyclobutenyl, azide, ethylene oxide, di(alkyl)amino, cyanate, hydroxy, ester, glycidyl ether, C1-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) alkyl acrylates, C1-10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) alkyl methacrylates, vinyl, vinyloxy, perfluorovinyl, perfluorovinyloxy, ethynyl, maleimide, phthalimide, alkylsiloxy, alkylsilyl, etc., and their halogenated derivatives.

[0052] Preferably, the crosslinkable group is selected from at least one of the following groups:

[0053] (Preferred) ), (Preferred) ), (Preferred) ), (Preferred) ), (Preferred) ), (Preferred) ), (Preferred) ), Here, -* represents the linking site of a group.

[0054] R A Each is independently selected from any one of C1-C6 (e.g., C2, C3, C4, C5, etc.) straight-chain or branched alkyl groups, with methyl and ethyl being more preferred.

[0055] R B R C R DEach is independently selected from hydrogen, halogen, unsubstituted or halogenated C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl, unsubstituted or halogenated C2-C20 (e.g., C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkenyl, and unsubstituted or halogenated C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl.

[0056] R N Each is independently selected from any one of hydrogen, unsubstituted or halogenated C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl, unsubstituted or halogenated C2-C20 (e.g., C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkenyl, and unsubstituted or halogenated C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl.

[0057] Preferably, the crosslinkable group is selected from at least one of the following groups:

[0058]

[0059] More preferably, the crosslinkable group is selected from... At least one of .

[0060] Preferably, the Ar2 group is selected from any one of the following groups:

[0061] Here, -* represents the linking site of a group.

[0062] R2 and R3 are each independently selected from any one of the following: crosslinkable groups, halogens, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups.

[0063] p represents The number of integers is selected from 0 to 5, for example, it can be 0, 1, 2, 3, 4, or 5. When p ≥ 2, multiple These can be the same or different groups.

[0064] q and r represent the number of substituents R2 and R3, respectively. q and r are each independently selected from integers between 0 and 4, for example, they can be 0, 1, 2, 3, or 4. When q = 0, it means that there are no substituents on the benzene ring and it is all hydrogen. When q ≥ 2, multiple R2s are the same or different groups. Similarly, r is also represented. For the sake of simplicity, it will not be elaborated further.

[0065] Preferably, R2 and R3 are each independently selected from C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, or C9, etc.) cycloalkyl groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy groups, C1-C Any one of the following: 20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkylthio, unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl, unsubstituted or R'-substituted C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl.

[0066] More preferably, the Ar2 is selected from any one of the following groups, whether substituted or unsubstituted:

[0067] Here, -* represents the linking site of a group.

[0068] Preferably, the Ar1 is selected from any one of the following groups:

[0069] Here, -* represents the linking site of a group.

[0070] R 11 R 12 R 13 R 14 Each is independently selected from any one of the following: crosslinkable groups, halogens, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups.

[0071] Z is selected from O, S, CR 15 R 16 or NAr 11 Any one of them.

[0072] R 15 R 16 Each is independently selected from any one of crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C30 aryl groups.

[0073] Ar 11 It is selected from any one of the following: crosslinkable groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups.

[0074] L1 is selected from any one of single bond, unsubstituted or R'-substituted C6-C30 arylene, and unsubstituted or R'-substituted C3-C30 heteroarylene.

[0075] R' is independently selected from any one or a combination of at least two of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C20 straight-chain or branched alkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, C3-C20 cycloalkyl groups, C2-C20 heterocycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C3-C30 arylamino groups, and C3-C30 heteroarylamino groups.

[0076] In the aforementioned groups, a, b, d, e, f, and g represent substituents R. 11 R 12 R 13 R 14 The number of R groups. Here, a, f, and g are each independently selected from integers 0-4, for example, 0, 1, 2, 3, or 4. b is selected from integers 0-5, for example, 0, 1, 2, 3, 4, or 5. d is selected from integers 0-7, for example, 0, 1, 2, 3, 4, 5, 6, or 7. e is selected from integers 0-3, for example, 0, 1, 2, or 3. When a = 0, it indicates that the six-membered ring contains no substituents and is entirely hydrogen; when a ≥ 2, multiple R groups are present. 11 These can be the same or different groups; the same applies to b, d, e, f, and g. For the sake of simplicity, they will not be described in detail.

[0077] In the aforementioned groups, c represents The number of. c is an integer selected from 0 to 4, for example, it can be 0, 1, 2, 3 or 4. When c ≥ 2, multiple These can be the same or different groups.

[0078] Preferably, the R 11 R 12 R 13 R 14Each is independently selected from crosslinkable groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, or C9, etc.) cycloalkyl groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy groups, C1-C20 Any one of the following: (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkylthio, unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl, unsubstituted or R'-substituted C3-C20 (e.g., C3, C4, C5, C6, C9, C10, C12, C14, C15, C16, or C18, etc.) heteroaryl.

[0079] Preferably, the R 15 R 16 Each is independently selected from any one of the following: crosslinkable groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups.

[0080] Preferably, the Ar 11 Selected from any one of the crosslinkable groups, unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups; Ar 11 Each of the R's mentioned herein is independently selected from any one of the following: C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.), C3-C10 (e.g., C4, C5, C6, C7, C8, or C9, etc.) cycloalkyl, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy, and C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkylthio.

[0081] In this context, L1 is exemplary including, but not limited to, any one of the following groups: single bond, unsubstituted, or R' substituted: phenylene, naphthylene, anthracene, phenanthrene, fluoranthylene, biphenylene, terphenylene, tetraphenylene, trimethyleneene, 9,9-dimethylfluorene, 9,9-diphenylfluorene, 9-methyl-9-phenylfluorene, spirofluorene, benzo[a]fluorene, benzo[a]furanyl, benzo[a]thiophene, dibenzo[a]furanyl, dibenzo[a]thiophene, dibenzo[a]fluorene, benzo[a]naphtho[a]furanyl, benzo[a]naphtho[a]thiophene, benzo[a]naphtho[a]fluorene, etc.

[0082] Preferably, L1 is selected from any one of single-bonded, unsubstituted, or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) arylene groups, and more preferably single-bonded, phenylene, or biphenylene.

[0083] Preferably, the Ar1 is selected from any one of the following groups, whether substituted or unsubstituted:

[0084] Here, -* represents the linking site of a group.

[0085] R 15 R 16 Each group is independently selected from any one of crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C30 aryl groups. More preferably, any one of crosslinkable groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups.

[0086] R 1A R 1B Each can be independently represented from unsubstituted, monosubstituted to the most permissible substitution; specifically, R 1A Indicates no substitution (R) 1A (for hydrogen), monosubstituted, disubstituted, trisubstituted, etc.; R 1B Indicates no substitution (R) 1B (e.g., hydrogen), monosubstituted, disubstituted, trisubstituted, etc.

[0087] R 1A R 1BEach group is independently selected from any one of hydrogen, crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, and C1-C30 alkylthio groups. More preferably, hydrogen, crosslinkable groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, C3-C10 (e.g., C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups, and C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy groups are selected from any one of these groups. Even more preferably, these groups are selected from any one of these groups. Any one of C1-C20 straight-chain or branched alkyl, C3-C10 cycloalkyl, and C1-C20 alkoxy.

[0088] More preferably, the Ar1 is selected from any one of the following groups:

[0089]

[0090] -* represents the linking site of a functional group.

[0091] R 15 '、R 16 Each is independently selected from any one of C1-C30 straight-chain or branched alkyl groups, or unsubstituted or R'-substituted C6-C30 aryl groups, and more preferably any one of C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, or unsubstituted or R'-substituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups.

[0092] R 1C Each is independently selected from any one of hydrogen, C1-C30 straight-chain or branched alkyl, C3-C30 cycloalkyl, C1-C30 alkoxy, and C1-C30 alkylthio, and more preferably any one of C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl, C3-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) cycloalkyl, and C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy.

[0093] Preferably, L is selected from any one of single-bonded, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16 or C18, etc.) arylene groups, and more preferably single-bonded or phenylene groups.

[0094] Preferably, each of the R1 groups is independently selected from crosslinkable groups, substituted or unsubstituted C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups, substituted or unsubstituted C3-C20 (e.g., C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) cycloalkyl groups, and substituted or unsubstituted C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups. The following are preferred: alkoxy groups, substituted or unsubstituted C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkylthio groups, substituted or unsubstituted C6-C20 (e.g., C6, C9, C10, C12, C14, C15, C16, or C18, etc.) aryl groups; further preferred are crosslinkable groups, C1-C20 straight-chain or branched alkyl groups, C3-C10 cycloalkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, and substituted or unsubstituted phenyl groups; even more preferred are... Any one of the following: C1-C20 straight-chain or branched alkyl, C3-C10 cycloalkyl, C1-C20 alkoxy, and C1-C20 alkylthio.

[0095] Preferably, each of the substituents in R1 is independently selected from any one of halogens, crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups. More preferably, crosslinkable groups, C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C...) are also selected. 16. Any one of the following: straight-chain or branched alkyl groups (e.g., C2, C3, C4, C5, C6, C7, C8, C9); cycloalkyl groups (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.); alkoxy groups (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.); and alkylthio groups (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.).

[0096] Preferably, each m is independently selected from an integer between 0 and 2.

[0097] Preferably, n Each group is independently selected from any one of the following groups:

[0098] -* represents the linking site of a functional group.

[0099] R 10 R 20 Each is independently selected from any one of C1-C30 straight-chain or branched alkyl, C3-C30 cycloalkyl, C1-C30 alkoxy, and C1-C30 alkylthio, and more preferably any one of C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl, C3-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) cycloalkyl, and C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy.

[0100] Preferably, R1 contains at least one (e.g., two, three, four, etc.) R alkyl And / or, the substituents described in Ar1 and Ar2 contain at least one (e.g., two, three, four, etc.) R. alkyl The R alkyl It is selected from any one of C1-C30 straight-chain or branched alkyl, C1-C30 alkoxy, C1-C30 alkylthio, and C3-C30 cycloalkyl.

[0101] As a preferred embodiment of the present invention, R1 contains at least one R alkyl And / or, the substituents in Ar1 and Ar2 contain at least one R. alkyl Therefore, the repeating units of the crosslinkable polymer contain alkane groups, which reduces the local rigidity of the molecule and helps increase the solubility of the crosslinkable polymer, meeting the requirements of solution processing. The crosslinkable polymer provided by this invention has good solubility in conventional organic solvents, including but not limited to: any one or at least two combinations of toluene, xylene, cyclohexylbenzene, methyl benzoate, and cyclohexanone. Solutions prepared using the crosslinkable polymer of this invention can meet the requirements of solution processing methods, such as inkjet printing and spin coating.

[0102] Preferably, R1 contains at least one R alkyl And / or, the substituents described in Ar1 contain at least one R.alkyl .

[0103] Preferably, the R alkyl It is selected from any one of the following: C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) straight-chain or branched alkyl groups; C1-C20 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, etc.) alkoxy groups; and C3-C10 (e.g., C2, C3, C4, C5, C6, C7, C8, C9, etc.) cycloalkyl groups.

[0104] Preferably, the crosslinkable polymer has a structure shown in any one of A1-A12:

[0105]

[0106]

[0107]

[0108]

[0109] Where x has the same definition as in Equation I.

[0110] Preferably, the weight-average molecular weight of the crosslinkable polymer is 30,000-500,000, for example, it can be 40,000, 50,000, 60,000, 80,000, 100,000, 150,000, 200,000, 250,000, 300,000, 350,000, 400,000, or 450,000.

[0111] In a second aspect, the present invention provides an application of the crosslinkable polymer as described in the first aspect, wherein the crosslinkable polymer is applied to organic electronic devices.

[0112] Preferably, the organic electronic device includes an organic electroluminescent device, an optical sensor, a solar cell, a lighting element, an organic thin-film transistor, an organic field-effect transistor, an organic thin-film solar cell, an information tag, an electronic artificial skin sheet, a sheet-type scanner, or electronic paper.

[0113] Preferably, the crosslinkable polymer is used in organic electroluminescent devices.

[0114] Preferably, the crosslinkable polymer serves as a hole transport material in an organic electroluminescent device.

[0115] Thirdly, the present invention provides an organic electroluminescent (OLED) device, the organic electroluminescent device comprising a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer is prepared by a material comprising at least one crosslinkable polymer as described in the first aspect.

[0116] Preferably, the organic layer includes a hole transport layer, and the material used to prepare the hole transport layer includes at least one crosslinkable polymer as described in the first aspect.

[0117] The crosslinkable polymer provided by this invention contains a triarylamine system with two pinaphthylamine structures in its repeating unit. The polymer backbone is constructed through aromatic rings with specific structure, number and connection mode, so that a large conjugated system is formed in the crosslinkable polymer. It has a suitable HOMO energy level, high hole mobility and high triplet energy level. As a hole transport material, it can significantly improve the luminescence performance and working life of organic electroluminescent devices.

[0118] More preferably, the introduction of alkane groups into the crosslinkable polymer can reduce the local rigidity of the molecule, help increase the solubility of the molecule, and meet the requirements of solution processing.

[0119] In this invention, the crosslinkable polymer, as a hole transport material, exhibits excellent solubility in conventional organic solvents (including but not limited to: toluene, xylene, cyclohexylbenzene, methyl benzoate, and cyclohexanone, or combinations of at least two of these). Solutions prepared using the crosslinkable polymer of this invention can meet the requirements of solution processing methods, such as inkjet printing and spin coating. After film formation, the crosslinkable polymer can undergo a secondary crosslinking reaction under heating, resulting in a three-dimensional network formed in the polymer film. This further increases the molecular weight and reduces solubility, maintaining excellent hole transport performance while exhibiting strong solvent resistance. This allows it to meet the diverse solvent requirements of the next functional layer, thereby solving the problem of mutual solubility between the hole transport layer and adjacent layers, resulting in devices with excellent overall performance.

[0120] In a preferred embodiment, the method for preparing the hole transport layer / the method for crosslinking the crosslinkable polymer includes:

[0121] A polymer solution is provided, the polymer solution comprising the crosslinkable polymer;

[0122] The polymer solution is coated onto a substrate to obtain a thin film;

[0123] The film is subjected to a crosslinking reaction, in which the crosslinkable polymer is crosslinked, to obtain a hole transport layer.

[0124] Preferably, the mass percentage of the crosslinkable polymer in the polymer solution is 0.1-10%, for example, it can be 0.2%, 0.5%, 0.8%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 7%, 8%, 9%, 9.5%, etc., and more preferably 0.5-5.0%.

[0125] Preferably, the solvent in the polymer solution includes any one or a combination of at least two of toluene, methyl benzoate, xylene, cyclohexylbenzene, cyclohexanone, and ethyl biphenyl.

[0126] If the solvent is low-boiling, the concentration of the crosslinkable polymer in the polymer solution can be low, for example, 0.1-2% is suitable; if the solvent is high-boiling, the concentration of the crosslinkable polymer in the polymer solution can be high, for example, 3-10% is suitable.

[0127] Preferably, the polymer solution includes an optional catalyst to facilitate or initiate the crosslinking reaction. The catalyst is known in the art; for example, for crosslinkable polymers containing unsaturated bonds (e.g., alkenyl groups), a free radical catalyst can be used. For crosslinkable polymers containing epoxy groups (glycidyl ether groups), urea or imidazole can be used. For crosslinkable polymers containing epoxy groups (glycidyl ether groups), the polymer solution includes an optional curing agent, which is any one or a combination of at least two of tetrahydrophthalic anhydride, methylbicyclo[2.2.1]-hept-2,3-dicarboxylic anhydride, and maleic anhydride.

[0128] Preferably, the coating method includes any one or a combination of at least two of spin coating, spray coating (including inkjet spraying), dip coating, and roll coating.

[0129] Preferably, the coating process further includes a solvent removal step, wherein the solvent removal method includes vacuum and / or heating.

[0130] Preferably, the temperature of the crosslinking reaction is ≥100℃, for example, it can be 120℃, 150℃, 180℃, 200℃, 220℃, 250℃, 280℃ or 300℃, more preferably ≥150℃, and even more preferably 200-300℃. This results in the crosslinked hole transport layer film having excellent solvent resistance and heat resistance.

[0131] Preferably, the crosslinking reaction time is ≥5 min, for example, it can be 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min or 120 min, and more preferably 10-60 min.

[0132] Preferably, the organic layer in the OLED device includes a hole transport region, a light-emitting layer, and an electron transport region; the material used to prepare the hole transport region includes at least one crosslinkable polymer as described in the first aspect.

[0133] Preferably, the hole transport region includes any one or a combination of at least two of the hole injection layer, hole transport layer, and electron blocking layer; the material used to prepare the hole transport layer includes at least one crosslinkable polymer as described in the first aspect.

[0134] Preferably, the electron transport region includes any one or a combination of at least two of the electron injection layer, electron transport layer, and hole blocking layer.

[0135] In a preferred embodiment, the organic light-emitting device (OLED device) includes a first electrode and a second electrode, and an organic layer located between the electrodes. The organic layer can be further divided into multiple regions, such as a hole transport region, a light-emitting layer, and an electron transport region; the material used to fabricate the hole transport region includes at least one crosslinkable polymer as described in the first aspect, and more preferably includes at least one of the crosslinkable polymers A1-A12.

[0136] In a preferred embodiment, the organic electroluminescent device includes a first electrode, a plurality of light-emitting functional layers (organic layers), and a second electrode arranged sequentially. The organic layers include a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer arranged sequentially, with the hole injection layer in contact with the first electrode (anode). The material used to prepare the hole transport layer includes at least one crosslinkable polymer as described in the first aspect.

[0137] In a preferred embodiment, a substrate can be used below the first electrode or above the second electrode. The substrate is typically made of glass or polymer material possessing excellent mechanical strength, thermal stability, water resistance, and transparency. Furthermore, the substrate used for a display may also incorporate thin-film transistors (TFTs).

[0138] The first electrode can be formed by sputtering or depositing the material to be used as the first electrode on a substrate. When the first electrode is used as the anode, it can be a transparent conductive oxide material such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), zinc oxide (ZnO), or any combination thereof. When the first electrode is used as the cathode, it can be a metal or alloy such as magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), ytterbium (Yb), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), or any combination thereof.

[0139] Organic layers can be formed on electrodes using methods such as vacuum thermal evaporation, spin coating, and printing. The compounds used as organic layers can be small organic molecules, large organic molecules, or polymers, as well as combinations thereof.

[0140] The hole transport region is located between the anode and the emissive layer. The hole transport region can be a single-layer hole transport layer (HTL), including single-layer hole transport layers containing only one compound and single-layer hole transport layers containing multiple compounds. Alternatively, the hole transport region can be a multilayer structure including at least one of a hole injection layer (HIL), a hole transport layer (HTL), and an electron blocking layer (EBL); wherein the HIL is located between the anode and the HTL, and the EBL is located between the HTL and the emissive layer.

[0141] In addition to the crosslinkable polymers provided by this invention, the materials for the hole transport region may also include phthalocyanine derivatives such as CuPc, conductive polymers or polymers containing conductive dopants such as polyphenylene oxide, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS), polyaniline / camphorsulfonic acid (Pani / CSA), polyaniline / poly(4-styrenesulfonate) (Pani / PSS), aromatic amine derivatives; or any combination thereof.

[0142] The hole injection layer is located between the anode and the hole transport layer. The hole injection layer can be a single compound material or a combination of multiple compounds. For example, the hole injection layer can be one or more compounds of the polymer described above, or one or more compounds of HI-1 to HI-3 described below; it can also be one or more of the polymer described above doped with one or more compounds of HI-1 to HI-3 described below.

[0143]

[0144] The emissive layer consists of a luminescent dye (i.e., a dopant) that emits different wavelengths of light and a host material. The emissive layer can be a monochromatic layer emitting a single color such as red, green, or blue. Multiple monochromatic emissive layers of different colors can be arranged in a planar pattern according to pixel design, or they can be stacked together to form a colored emissive layer. When different colored emissive layers are stacked together, they can be separated from each other or connected to each other. The emissive layer can also be a single colored emissive layer that simultaneously emits different colors such as red, green, and blue.

[0145] Depending on the technology used, the light-emitting layer material can be various, including fluorescent electroluminescent materials, phosphorescent electroluminescent materials, and thermally activated delayed fluorescence materials. An OLED device can employ a single light-emitting technology or a combination of different technologies. These different light-emitting materials, categorized by technology, can emit light of the same color or different colors.

[0146] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent host material of the light-emitting layer may be selected from, but is not limited to, one or more combinations of BFH-1 to BFH-17 listed below.

[0147]

[0148] In one aspect of the invention, the light-emitting layer employs fluorescent electroluminescence technology. The fluorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of BFD-1 to BFD-12 listed below.

[0149]

[0150]

[0151] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The main material of the light-emitting layer is selected from, but not limited to, one or more combinations of GPH-1 to GPH-80.

[0152]

[0153]

[0154]

[0155] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of GPD-1 to GPD-47 listed below.

[0156]

[0157]

[0158]

[0159] Where D represents deuterium.

[0160] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of RPD-1 to RPD-28 listed below.

[0161]

[0162]

[0163] In one aspect of the invention, the light-emitting layer employs phosphorescent photoluminescence technology. The phosphorescent dopant of the light-emitting layer may be selected from, but not limited to, one or more combinations of YPD-1 to YPD-11 listed below.

[0164]

[0165] The organic layer of an OLED may also include an electron transport region between the light-emitting layer and the cathode. The electron transport region can be a single-layer electron transport layer (ETL), including single-layer electron transport layers containing only one compound and single-layer electron transport layers containing multiple compounds. Alternatively, the electron transport region can be a multilayer structure including at least one of an electron injection layer (EIL), an electron transport layer (ETL), and a hole blocking layer (HBL).

[0166] In one aspect of the present invention, the electron transport layer material may be selected from, but not limited to, one or more combinations of ET-1 to ET-74 listed below.

[0167]

[0168]

[0169]

[0170]

[0171] In one aspect of the invention, a hole blocking layer (HBL) is located between the electron transport layer and the light-emitting layer. The hole blocking layer may employ one or more compounds of ET-1 to ET-74 described above.

[0172] The device may also include an electron injection layer located between the electron transport layer and the cathode. The electron injection layer material includes, but is not limited to, one or more combinations of the following: LiQ, LiF, NaCl, CsF, Li2O, Cs2CO3, BaO, Na, Li, Ca, Mg, Yb.

[0173] The present invention also provides a display device comprising an organic electroluminescent device as described in the third aspect.

[0174] Compared with the prior art, the present invention has the following beneficial effects:

[0175] The crosslinkable polymer provided by this invention has the structure shown in Formula I, in which each repeating unit contains a triarylamine system with two pinaphthylamine structures. Through the structural design of the polymer backbone constructed with aromatic rings of specific structure, number, and connection mode, the crosslinkable polymer possesses suitable HOMO energy levels, high hole mobility, and high triplet energy levels. As a hole transport material, it can significantly improve the luminous efficiency and lifetime of organic electroluminescent devices and reduce voltage. The crosslinkable polymer has good solubility, meeting the requirements of solution processing methods. After film formation, it can undergo a secondary crosslinking reaction. The polymer film after secondary crosslinking forms a three-dimensional network structure, further increasing the molecular weight and reducing solubility. While maintaining excellent hole transport performance, it has strong solvent resistance, meeting the various solvent requirements of the next functional layer. This solves the problem of mutual solubility between the hole transport layer and adjacent layers, endowing the device with superior overall performance and having significant value for the development of solution-based OLED device fabrication. Attached Figure Description

[0176] Figure 1 GPC test pattern of crosslinkable polymer A1 provided by the present invention;

[0177] Figure 2 The image shows a comparison of the ultraviolet spectra of the crosslinkable polymer A8 provided by this invention before and after solvent immersion. Detailed Implementation

[0178] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0179] In one specific embodiment, the crosslinkable polymer can be obtained by monomer polymerization of the structure shown in Formula IA;

[0180]

[0181] Wherein, L, Ar1, Ar2, R1, n and m have the same definition as in Formula I; Hal is selected from halogens, such as Cl, Br or I, with Br being preferred.

[0182] In one specific embodiment, the polymerization reaction is carried out in the presence of bis(1,5-cyclooctadiene)nickel(0), 2,2'-bipyridine and 1,5-cyclooctadiene.

[0183] In one specific embodiment, the monomer with the structure shown in Formula IA is prepared via the following representative synthetic route:

[0184]

[0185] In another specific embodiment, the intermediate A1 can also be prepared via the following synthetic route:

[0186]

[0187] In another specific embodiment, the intermediate A2 can also be prepared via the following synthetic route:

[0188]

[0189] In the aforementioned synthetic route, Hal1, Hal2, Hal3, and Hal4 are each independently selected from halogens, for example, any one of F, I, Br, or Cl; U1 and U2 are each independently selected from... Rx is an amino protecting group, such as a Boc protecting group.

[0190] In another specific embodiment, reactions I, II, III, and IV are carried out in the presence of a palladium catalyst.

[0191] It should be noted that obtaining the monomer and crosslinkable polymer is not limited to the synthesis methods and raw materials used in this invention. Those skilled in the art can also make conventional adjustments to the preparation method according to actual needs, or select other methods or routes to obtain the crosslinkable polymer proposed in this invention. Crosslinkable polymers of Formula I synthesized by those skilled in the art using other methods are also within the scope of protection of this invention.

[0192] The specific preparation method of the crosslinkable polymer of the present invention will be described in detail below using several synthetic examples, but the preparation method of the present invention is not limited to these synthetic examples.

[0193] The compounds, solvents, and reagents used in the synthesis methods not mentioned in this invention are all commercially available raw materials that can be purchased from the domestic chemical market or prepared in-house using known methods.

[0194] The mass spectrometry (m / z) characterization data of the intermediates and target products in the following specific embodiments of the present invention were obtained by testing with an Agilent 6530LC / Q-TOF mass spectrometer (APCI ion source).

[0195] In the following specific embodiments of the present invention, unless otherwise specified, "C" will be used. n H 2n+1 The alkyl groups indicated are all straight-chain alkyl groups with n carbon atoms.

[0196] Synthesis Example 1

[0197] The synthetic route for the monomer A1-monomer is as follows:

[0198]

[0199]

[0200] Synthesis of A1-1:

[0201] 4-Chloro-2-iodobromobenzene (10 g), p-vinylphenylboronic acid (5.2 g), potassium carbonate (5.2 g), and solvents toluene (150 mL), ethanol (30 mL), and water (30 mL) were added to a three-necked flask. Under nitrogen protection, the catalyst tetrakis(triphenylphosphine)palladium Pd(PPh3)4 (700 mg) was added. The reaction solution was continued to react under nitrogen atmosphere for 8 h. After cooling, the solution was extracted with saturated brine and toluene. The organic phase was dried with anhydrous sodium sulfate, filtered, and concentrated. The crude product was purified by silica gel column chromatography (petroleum ether PE / dichloromethane DCM, 20 / 1) to obtain 7.5 g of product, which was directly used in the next step.

[0202] Synthesis of A1-2:

[0203] In a three-necked flask, A1-1 (7.5 g), pinacol diborate (9.8 g), potassium acetate (5.0 g), (1,1'-bis(diphenylphosphine)ferrocene)palladium(II) dichloride Pd(dppf)Cl2 (100 mg), and dioxane (100 mL) were added. The reaction mixture was heated to 100 °C under nitrogen protection and reacted for 6 h. After cooling, the reaction solution was poured into water and extracted with ethyl acetate. The organic phase was washed with saturated ammonium chloride solution. After drying the organic phase, it was concentrated. The crude product was purified by column chromatography (PE / DCM, 5 / 1) to give 6.8 g of white solid, which was used directly in the next step.

[0204] Synthesis of A1-3:

[0205] p-Dibromobenzene (2.2 g), Al-2 (6.8 g), potassium carbonate (3.2 g), toluene (80 mL), ethanol (10 mL), and water (10 mL) were added to a three-necked flask and stirred until homogeneous. Under nitrogen protection, tetra(triphenylphosphine)palladium Pd(PPh3)4 (100 mg) was added, and the reaction mixture was allowed to react for 6 h. The mixture was then cooled. The product was extracted with saturated brine and toluene, dried over anhydrous sodium sulfate, filtered, and concentrated. The crude product was purified by silica gel chromatography (PE / DCM, 10 / 1) to obtain 4 g of the product, which was used directly in the next step.

[0206] Synthesis of A1-4:

[0207] A-M1 (10g), naphthalene 3-chloro-1-boronic acid (7.5g), and potassium carbonate (6.5g) were added to a three-necked flask. Under nitrogen protection, tetra(triphenylphosphine)palladium Pd(PPh3)4 (120mg) was added. The reaction mixture was heated to 90℃ and stirred for 6 hours. After cooling, the reaction mixture was poured into water and extracted with ethyl ester. The organic phase was washed with saturated ammonium chloride solution. After drying, the organic phase was concentrated. The crude product was purified by column chromatography (PE / DCM, 5 / 1) to give 8.8g of a white solid, which was used directly in the next step.

[0208] Synthesis of A1-5

[0209] In a three-necked flask, add Al-4 (8.8 g), pinacol diborate (8.3 g), potassium acetate (4.2 g), tris(dibenzylacetone)dipalladium Pd2(dba)3 (100 mg), 2-dicyclohexylphosphine-2',6'-dimethoxybiphenyl SPhos (100 mg), and dioxane (100 mL). The reaction mixture is heated to 100 °C under nitrogen protection and reacted for 6 h. After cooling, the reaction solution is poured into water and extracted with ethyl acetate. The organic phase is washed with saturated ammonium chloride solution. After drying, the organic phase is concentrated. The crude product is purified by column chromatography (PE / DCM, 5 / 1) to give 7.5 g of a white solid, which is used directly in the next step.

[0210] Synthesis of A1-6

[0211] In a three-necked flask, Al-3 (4 g), Al-5 (8.6 g), potassium carbonate (2.7 g), Pd2(dba)3 (110 mg), SPhos (100 mg), toluene (100 mL), ethanol (15 mL), and water (15 mL) were added. The reaction mixture was heated to 90 °C under nitrogen protection and reacted for 16 h. After cooling, saturated brine was added, and the mixture was extracted with toluene. The organic phase was concentrated, and the crude product was purified by silica gel column chromatography (PE / DCM, 5 / 1) to obtain 8 g of solid.

[0212] Synthesis of A1-7

[0213] Add 8g of A1-6 to 100mL of dichloromethane, then add 2mL of trifluoroacetic acid and stir at room temperature for 5h. Pour in a dilute sodium bicarbonate solution, extract with dichloromethane, concentrate and dry the organic phase to obtain 6g of solid, MS (M+H): 969.21.

[0214] Synthesis of A1-8

[0215] Add A1-7 (6g), 4-octylbromobenzene (3.5g), and sodium tert-butoxide (1.3g) to a three-necked flask containing toluene (100mL). Under nitrogen protection, add Pd2(dba)3 (200mg) and SPhos (200mg). Heat the reaction system to 90℃ and continue stirring for 16h. After cooling, pass the reaction solution through a short silica gel column and wash with dichloromethane until no product is obtained. Concentrate the filtrate to obtain the crude product. Further purify the crude product by column chromatography to obtain 6.0g of product, MS (M+H): 1345.43.

[0216] Synthesis of A1-monomer

[0217] Under nitrogen protection, Al-8 (6 g) and 4-bromo-4'-iodobiphenyl (3.5 g) were dissolved in a round-bottom flask containing toluene (100 mL) and stirred until homogeneous. Then, Pd2(dba)3 (100 mg) and 1,1'-bis(diphenylphosphine)DPPF (130 mg) were added, and the mixture was stirred for 5 min. Sodium tert-butoxide (1.5 g) was then added to the resulting solution. The reaction system was stirred at 95 °C for 18 h under nitrogen conditions. After cooling, the mixture was passed through a short silica gel column and washed with toluene. The mixed solution was concentrated and then purified by silica gel column chromatography (PE / DCM, 3 / 1) to give 5.6 g of a white solid, MS (M+H): 1805.39.

[0218] Synthesis of crosslinkable polymer A1

[0219] Weigh 1.7 g of bis(1,5-cyclooctadiene)nickel(0) in a glove box and place it in a dry round-bottom flask. Then weigh 0.97 g of 2,2'-bipyridine and 0.67 g of 1,5-cyclooctadiene and dissolve them in 15 mL of dry N,N'-dimethylformamide. Add this solution to the flask containing bis(1,5-cyclooctadiene)nickel(0) and heat to 60 °C with stirring for 30 min. Next, add 5.6 g of monomer Al-Monomer to a single-necked flask and dissolve it in 120 mL of dry toluene. Then add this toluene solution to the catalyst system described above. Heat the reaction system to 80 °C and react for 18 h. After cooling, remove the reaction system from the glove box and pour it into a concentrated hydrochloric acid / methanol solution (1.5%, V / V). Stir for 2 h, filter to collect the precipitated solid, and dry it thoroughly. The polymer was then dissolved in toluene, and the solution was added dropwise to a concentrated hydrochloric acid / methanol solution to precipitate a solid. The solid was collected, stirred in methanol for 1 hour, and collected again to obtain a white polymer. The molecular weight of the polymer was determined by gel permeation chromatography (GPC) with tetrahydrofuran (THF) as the mobile phase and polystyrene as the reference. The GPC chromatogram is shown below. Figure 1 As shown, the weight-average molecular weight Mw is 108714, and the number-average molecular weight Mn is 46913.

[0220] Synthesis Example 2

[0221] The synthetic route for the monomer A10-monomer is as follows:

[0222]

[0223]

[0224] Synthesis of A10-1:

[0225] 2,5-Dihexyl-1,4-dibromobenzene (10 g), p-chlorophenylboronic acid (8.5 g), potassium carbonate (8.0 g), and solvents toluene (150 mL), ethanol (30 mL), and water (30 mL) were added to a three-necked flask. Under nitrogen protection, tetrakis(triphenylphosphine)palladium Pd(PPh3)4 (700 mg) was added. The reaction solution was continued to react under nitrogen atmosphere for 8 h. After cooling, the solution was extracted with saturated brine and toluene. The organic phase was dried with anhydrous sodium sulfate, filtered, and concentrated. The crude product was purified by silica gel chromatography (PE / DCM, 20 / 1) to obtain 10 g of product. MS (M+H): 467.26.

[0226] Synthesis of A10-2:

[0227] 3-Chloro-1-naphthoic acid (10 g), 1-bromo-2-nitronaphthalene (13.5 g), potassium carbonate (8.3 g), toluene (150 mL), ethanol (30 mL), and water (30 mL) were added to a three-necked flask and stirred until homogeneous. Under nitrogen protection, tetrakis(triphenylphosphine)palladium Pd(PPh3)4 (600 mg) was added as a catalyst. The reaction mixture was allowed to react for 6 h, and then cooled. The product was extracted with saturated brine and toluene. The organic phase was dried over anhydrous sodium sulfate, filtered, and concentrated. The crude product was purified by silica gel chromatography (PE / DCM, 10 / 1) to obtain 10 g of product, which was used directly in the next step.

[0228] Synthesis of A10-3:

[0229] In a three-necked flask, A10-2 (10 g), pinacol diboronate (11 g), potassium acetate (6.3 g), Pd2(dba)3 (120 mg), SPhos (120 mg), and dioxane (100 mL) were added. The reaction mixture was heated to 100 °C under nitrogen protection and reacted for 6 h. After cooling, the reaction solution was poured into water and extracted with ethyl acetate. The organic phase was washed with saturated ammonium chloride solution. After drying the organic phase, it was concentrated. The crude product was purified by column chromatography (PE / DCM, 5 / 1) to give 9.6 g of white solid, which was used directly in the next step.

[0230] Synthesis of A10-4:

[0231] In a three-necked flask, 5 g of A10-1, 10 g of A10-3, 4.5 g of potassium carbonate, 200 mg of Pd2(dba)3, 200 mg of SPhos, 80 mL of toluene, 15 mL of ethanol, and 15 mL of water were added. The reaction mixture was heated to 90 °C under nitrogen protection and reacted for 16 h. After cooling, saturated brine was added, and the mixture was extracted with toluene. The organic phase was concentrated, and the crude product was purified by silica gel column chromatography (PE / DCM, 5 / 1) to obtain 8.3 g of solid.

[0232] Synthesis of A10-5:

[0233] Add 8.3 g of A10-4 to 100 mL of methanol, then add 0.8 g of 10% wet palladium / carbon. Reflux the reaction mixture for 3 h, then cool. Filter to remove the palladium / carbon, concentrate most of the solvent in the filtrate, and extract with dichloromethane and saturated brine. Concentrate and dry the organic phase to obtain 7 g of solid. MS (M+H): 933.22.

[0234] Synthesis of A10-6:

[0235] Add 5g of A10-5, 5.2g of A-M2, and 1.2g of sodium tert-butoxide to a three-necked flask containing 100mL of toluene. Under nitrogen protection, add 200mg of Pd2(dba)3 and 200mg of SPhos. Heat the reaction system to 90℃ and stir for 16h. After cooling, pass the reaction solution through a short silica gel column and wash with dichloromethane until no product is obtained. Concentrate the filtrate to obtain the crude product. Further purify the crude product by column chromatography to obtain 6.9g of product, MS (M+H): 1689.68.

[0236] Synthesis of A10-monomer

[0237] Under nitrogen protection, A10-6 (5 g) and 4-bromo-4'-iodobiphenyl (2.3 g) were dissolved in a round-bottom flask containing toluene (120 mL) and stirred until homogeneous. Then, Pd2(dba)3 (100 mg) and DPPF (130 mg) were added, and the mixture was stirred for 5 min. Finally, sodium tert-butoxide (800 mg) was added to the resulting solution. The reaction system was stirred at 95 °C for 18 h under nitrogen conditions. After cooling, the mixture was passed through a short silica gel column and washed with toluene. The solution was concentrated and then purified by silica gel column chromatography (PE / DCM, 3 / 1) to give 3.3 g of solid, MS (M+H): 2149.73.

[0238] Synthesis of crosslinkable polymer A10: Referring to the synthesis method of crosslinkable polymer A1, the monomer A1-monomer was replaced with A10-monomer to obtain crosslinkable polymer A10.

[0239] Synthesis Example 3

[0240] The synthetic route for the monomer A12-monomer is as follows:

[0241]

[0242] Synthesis of A12-1:

[0243] 1-Chloro-3-naphthoic acid (9.5 g), 2,5-dihexyl-1,4-dibromobenzene (8 g), potassium carbonate (8.2 g), and solvents toluene (120 mL), ethanol (20 mL), and water (20 mL) were added to a three-necked flask. Under nitrogen protection, the catalyst tetrakis(triphenylphosphine)palladium Pd(PPh3)4 (500 mg) was added. The reaction mixture was continued to react under nitrogen atmosphere for 8 h. After cooling, the mixture was extracted with saturated brine and toluene. The organic phase was dried with anhydrous sodium sulfate, filtered, and concentrated. The crude product was purified by silica gel chromatography (PE / DCM, 10 / 1) to obtain 8.5 g of product, which was directly used in the next step.

[0244] Synthesis of A12-2:

[0245] In a three-necked flask, A12-1 (8.5 g), 2-nitro-1-naphthoic acid (7.2 g), potassium carbonate (6.2 g), Pd2(dba)3 (250 mg), SPhos (250 mg), toluene (120 mL), ethanol (25 mL), and water (25 mL) were added. The reaction mixture was heated to 90 °C under nitrogen protection and reacted for 16 h. After cooling, saturated brine was added, and the mixture was extracted with toluene. After concentrating the organic phase, the crude product was purified by silica gel column chromatography (PE / DCM, 5 / 1) to obtain 9.6 g of solid, which was used directly in the next step. MS (M+H): 841.20.

[0246] Synthesis of A12-3:

[0247] Add 9g of A12-2 to 150mL of methanol, then add 1g of 10% wet palladium / carbon. Reflux the reaction mixture for 3 hours, then cool it down. Filter to remove the palladium on carbon, wash with dichloromethane, concentrate most of the solvent in the filtrate, and extract with dichloromethane and saturated brine. Concentrate and dry the organic phase to obtain 7.5g of solid.

[0248] Synthesis of A12-4:

[0249] Add 5g of A12-3, 7.8g of A-M3, and 1.6g of sodium tert-butoxide to a three-necked flask containing 110mL of toluene. Under nitrogen protection, add 180mg of Pd2(dba)3 and 180mg of SPhos. Heat the reaction system to 90℃ and stir for 16h. After cooling, pass the reaction solution through a short silica gel column and wash with dichloromethane until no product is obtained. Concentrate the filtrate to obtain the crude product. Further purify the crude product by column chromatography to obtain 8.3g of product, MS (M+H): 1787.74.

[0250] Synthesis of A12-monomer:

[0251] Under nitrogen protection, A12-4 (5 g) and p-bromoiodobenzene (2.3 g) were dissolved in a round-bottom flask containing toluene (100 mL) and stirred until homogeneous. Then, Pd2(dba)3 (100 mg) and DPPF (130 mg) were added, and the mixture was stirred for 5 min. Finally, sodium tert-butoxide (0.8 g) was added to the resulting solution. The reaction system was stirred at 95 °C for 18 h under nitrogen conditions. After cooling, the mixture was passed through a short silica gel column and washed with toluene. The solution was concentrated and then purified by silica gel column chromatography (PE / DCM, 4 / 1) to give 3.2 g of solid, MS (M+H): 2247.66.

[0252] Synthesis of crosslinkable polymer A12: Referring to the synthesis method of crosslinkable polymer A1, the monomer A1-monomer was replaced with A12-monomer to obtain crosslinkable polymer A12.

[0253] The molecular weights of the crosslinkable polymers A1-A12 provided in this invention were determined by gel permeation chromatography (GPC), using THF as the mobile phase and polystyrene as a reference. The weight-average molecular weights (Mw) and number-average molecular weights (Mn) of each crosslinkable polymer are shown in Table 1.

[0254] Table 1

[0255]

[0256]

[0257] Solvent resistance test of crosslinkable polymers:

[0258] The crosslinkable polymer provided by this invention was dissolved in cyclohexylbenzene at a concentration of 2% and filtered using a disposable syringe. On a clean glass substrate, the film was coated at a high speed of 4000 rpm for 30 seconds. The resulting film was then placed in a vacuum oven and heated to 60°C to further remove the solvent. The film was then heated in a nitrogen-filled furnace at 250°C for 30 minutes to induce crosslinking. The UV-Vis absorption spectra of the film before and after crosslinking were measured using a UV-Vis spectrophotometer (SHIMADZU UV-2600i). The film was then immersed in toluene for 5 minutes, rinsed, and dried. The absorption spectrum of the film after toluene immersion was measured, and the changes in the UV-Vis absorption spectra before and after toluene immersion were observed.

[0259] In contrast, after removing the solvent from the film, instead of performing the 250°C high-temperature crosslinking operation, the film was directly immersed in toluene for 5 minutes, rinsed and dried, and the absorption spectrum was measured.

[0260] The UV spectrum comparison of the crosslinkable polymer A8 before and after immersion in solvent (toluene) is shown in the figure below. Figure 2 As shown, from Figure 2 As can be seen, the UV-Vis absorption spectra of the film before and after crosslinking (without immersion in toluene) are basically the same. The absorption spectrum of the film after heating and crosslinking only changes slightly after immersion in toluene, indicating that contact with toluene has basically no effect on the crosslinked and cured film. The film formed by crosslinking the crosslinkable polymer has excellent solvent resistance. However, the absorption spectrum of the film that has not been crosslinked at high temperature decreases significantly after immersion in toluene, indicating that some of the film dissolves. The solvent resistance of the uncrosslinked polymer is poor.

[0261] Device Example 1

[0262] An organic electroluminescent device includes an anode (ITO), a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a cathode (Al) arranged sequentially; its fabrication method is as follows:

[0263] (1) After ultrasonic treatment of the glass plate coated with ITO transparent conductive layer in commercial cleaning agent, it is rinsed in deionized water, ultrasonically degreased in acetone / ethanol mixed solvent, baked in a clean environment until the moisture is completely removed, cleaned with ultraviolet light and ozone, and bombarded with low-energy cation beam.

[0264] (2) Place the glass substrate with the anode in a glove box under nitrogen protection, filter the PEDOT:PSS solution with a disposable needle filter, take 40 μL of the filtered PEDOT:PSS solution each time and spin coat it onto the pretreated ITO substrate. The spin coating speed is 4000 r / min and the duration is 30 s. Transfer it to a hot stage at 140°C and anneal for 20 min to form a 50 nm hole injection layer film on the surface of the pretreated ITO substrate.

[0265] (3) Dissolve the crosslinkable polymer A1 provided by the present invention in toluene to prepare a 20 mg / mL solution. Filter the solution using a disposable needle filter. Take 40 μL of the solution each time and spin-coat it onto the surface of the hole injection layer film. Coat it at a high speed of 4000 r / min for 30 s. Place it on a hot stage under a nitrogen atmosphere and anneal it at 100 °C for 20 min to remove the solvent. Then heat the hot stage to 250 °C for 30 min to allow the crosslinkable groups to react and form a polymer. A 50 nm hole transport layer film is formed on the surface of the hole injection layer film.

[0266] (4) The light-emitting layer of the device is fabricated on the hole transport layer using a solution method. The light-emitting layer consists of a ternary mixture of a host material (GPH-41:GPH-8 = 1:1, w / w) and a dopant material (dye, GPD-1). The mass percentage of the dopant material in the light-emitting layer is 3%. The aforementioned material is dissolved in toluene solvent to prepare a solution with a total concentration of 10 mg / mL of the ternary mixture. The solution is mixed uniformly by sonication. 40 μL of the mixed solution is spin-coated onto the surface of the hole injection layer film obtained in step (3) at a rotation speed of 3000 r / min for 30 s. The solvent is removed by heating and annealing at 80 °C for 10 min under a nitrogen atmosphere. A 30 nm light-emitting layer is formed on the surface of the hole transport layer film.

[0267] (5) A mixture of compound ET-61:ET-57 (50 / 50, w / w) was vacuum-deposited on the light-emitting layer as an electron transport layer at a deposition rate of 0.1 nm / s and a total film thickness of 20 nm.

[0268] (6) A 1 nm thick LiF layer was vacuum-deposited on the electron transport layer as an electron injection layer at a deposition rate of 0.1 nm / s.

[0269] (7) A 100 nm thick layer of metallic aluminum is vacuum-deposited on the electron injection layer as a cathode, and the deposition rate is controlled at 1 nm / s to obtain the organic electroluminescent device.

[0270] Device Examples 2-12

[0271] An organic electroluminescent device differs from Example 1 only in that the material of the hole transport layer is replaced with the crosslinkable polymer in Table 2; the other layers, thicknesses, materials, and preparation methods are the same as those in Example 1.

[0272] Device Example 13

[0273] An organic electroluminescent device differs from Example 1 only in that the 250°C heating crosslinking operation is not performed in step (3), that is, after annealing at 100°C for 20 minutes to remove the solvent, it directly proceeds to the preparation of the light-emitting layer in step (4); the other layers, thicknesses, materials and preparation methods are the same as those in Example 1.

[0274] Device Example 14

[0275] An organic electroluminescent device differs from Example 1 only in that the 250°C heating crosslinking operation is not performed in step (3). Instead, after annealing at 100°C for 20 minutes to remove the solvent, the light-emitting layer is directly prepared. The light-emitting layer is prepared by vapor deposition. The light-emitting layer consists of a ternary mixture of a host material (GPH-41:GPH-8 = 1:1) and a dopant material (dye, GPD-1). The mass percentage of the dopant material in the light-emitting layer is 3%. The vapor deposition rate is 0.1 nm / s, forming a light-emitting layer with a thickness of 30 nm. Other layers, thicknesses, materials, and preparation methods are the same as in Example 1.

[0276] Device Comparison Example 1

[0277] An organic electroluminescent device differs from Example 1 only in that the material of the hole transport layer is replaced with polymer Ref-1 as shown below; the other layers, thicknesses, materials, and preparation methods are the same as those in Example 1.

[0278] The weight-average molecular weight Mw = 110653 can be obtained by referring to the existing technology WO2010065500A2.

[0279] Device Comparison Example 2

[0280] An organic electroluminescent device differs from Example 1 only in that the hole transport layer material is replaced with polymer Ref-1; and the light-emitting layer is prepared by vapor deposition: the light-emitting layer comprises a ternary mixture of host material (GPH-41:GPH-8 = 1:1) and dopant material (dye, GPD-1), with the dopant material having a mass percentage content of 3% in the light-emitting layer; the vapor deposition rate is 0.1 nm / s, forming a light-emitting layer with a thickness of 30 nm; other layers, thicknesses, materials, and preparation methods are the same as in Device Example 1.

[0281] The performance of the above-mentioned organic electroluminescent devices was tested using the following methods:

[0282] At the same brightness of 1000 cd / m² 2 The voltage and current density of the organic electroluminescent device were measured using a digital source meter and a luminance meter. The ratio of luminance to current density is the current efficiency. Maintaining a constant current, the device's luminance was recorded from an initial value of 10000 cd / m². 2 Attenuation to 9500 cd / m 2 The time taken was used to obtain the test value of LT95 lifespan; the test results are shown in Table 2.

[0283] Table 2

[0284]

[0285]

[0286] As shown in the table above, this invention, through the structural design of a polymer backbone comprising two binaphthalene and aromatic amine units, enables the crosslinkable polymer to possess excellent hole transport performance. As a material for preparing the hole transport layer, it can effectively improve the luminous efficiency and lifetime of the device while reducing voltage. The crosslinkable polymer exhibits excellent solubility, meeting the requirements of solution processing methods, and the crosslinking reaction can be achieved through a simple method to obtain the crosslinked polymer. This polymer maintains excellent hole transport performance while also possessing good solvent resistance, resulting in superior device performance.

[0287] Comparing Device Example 8 and Device Example 13, it can be seen that the uncrosslinked polymer has poor resistance to solvent erosion. The solvent in the light-emitting layer wets the hole transport layer, causing it to dissolve and disrupting the interface between the light-emitting layer and the hole transport layer. This severely affects the transport of hole carriers, and the excitons generated by the light-emitting layer are quenched due to the imbalance of charge carriers, resulting in a significant performance degradation. In contrast, in Device Example 8, due to the improved solvent resistance of the crosslinked polymer, the hole transport layer is not dissolved by the light-emitting layer, ensuring the hole transport capability. The excitons are confined within the light-emitting layer, triggering dye luminescence, resulting in excellent device performance. Comparing Device Example 8 and Device Example 14, it can be seen that the crosslinked polymer A8 in Device Example 8 maintains the significantly superior performance of the hole transport material. This demonstrates that the triarylamine structure of the bis-naphthalene contained in this invention has a stronger conjugated system, which is beneficial for the dispersion of π electrons and facilitates the transition of π electrons between molecules, improving the hole mobility of the material. The device carrier transport is more balanced, resulting in excellent device performance.

[0288] The devices in Comparative Examples 1 and 2 use polymer hole transport materials containing a binatrimethyleneamine structure from existing technologies. In Comparative Example 1, the light-emitting layer is prepared by a solvent method. The solvent in the light-emitting layer has a wetting effect on the hole transport layer, resulting in low luminous efficiency, short lifetime, and poor overall performance in Comparative Example 1. Comparative Example 2 uses a vapor deposition method to form the light-emitting layer. Although the device performance is improved compared to Comparative Example 1, it is still significantly worse than the device performance using the crosslinkable polymer of the present invention in the examples. It can be seen that the present invention, through the design of a polymer backbone containing a binatrimethyleneamine structure and its combination with crosslinkable groups, enables the crosslinkable polymer to have excellent hole transport performance, which can effectively improve the luminous efficiency and lifetime of the device and reduce the voltage.

[0289] The applicant declares that the crosslinkable polymer and its applications are illustrated by the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A crosslinkable polymer, characterized in that, The crosslinkable polymer has a structure as shown in Formula I: Wherein, L is selected from any one of single bond, substituted or unsubstituted C6-C30 arylene, substituted or unsubstituted C3-C30 heteroarylene; Ar1 and Ar2 are each independently selected from any one of substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups; R1 is independently selected from any one of the following: halogen, crosslinkable group, substituted or unsubstituted C1-C30 straight-chain or branched alkyl, substituted or unsubstituted C3-C30 cycloalkyl, substituted or unsubstituted C1-C30 alkoxy, substituted or unsubstituted C1-C30 alkylthio, substituted or unsubstituted C6-C30 aryl, and substituted or unsubstituted C3-C30 heteroaryl. The substituents described in L, Ar1, Ar2, and R1 are each independently selected from any one of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C30 straight-chain or branched alkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, C3-C30 cycloalkyl groups, C2-C30 heterocycloalkyl groups, unsubstituted or R'-substituted C6-C30 aryl groups, unsubstituted or R'-substituted C3-C30 heteroaryl groups, unsubstituted or R'-substituted C3-C30 arylamino groups, and unsubstituted or R'-substituted C3-C30 heteroarylamino groups. R' is independently selected from any one or a combination of at least two of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C20 straight-chain or branched alkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, C3-C20 cycloalkyl groups, C2-C20 heterocycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C3-C30 arylamino groups, and C3-C30 heteroarylamino groups; Ar1, Ar2, and R1 contain at least one crosslinkable group, which is a group containing at least one of the following: C=C unsaturated bond, C≡C unsaturated bond, oxocyclic ring, azide group, hydroxyl group, ester group, cyanate group, isocyanate group, di(alkyl)amino group, siloxane group, and alkylsilyl group. n is an integer selected from 1 to 5; m are each independently selected from integers between 0 and 4; x represents the degree of polymerization of the crosslinked polymer, x≥1.

2. The crosslinkable polymer according to claim 1, characterized in that, The crosslinkable polymer has a structure as shown in any one of Formula II-1, Formula II-2, or Formula II-3: Among them, L, Ar1, Ar2, R1, n and m have the same limited range as Equation I.

3. The crosslinkable polymer according to claim 1 or 2, characterized in that, The crosslinkable group is selected from at least one of the following groups: Where -* represents the linking site of the group; R A Each is independently selected from any one of C1-C6 straight-chain or branched alkyl groups; R B R C R D Each is independently selected from any one of hydrogen, halogen, unsubstituted or halogenated C1-C20 straight-chain or branched alkyl, unsubstituted or halogenated C2-C20 alkenyl, and unsubstituted or halogenated C6-C20 aryl. R N Each is independently selected from any one of hydrogen, unsubstituted or halogenated C1-C20 straight-chain or branched alkyl, unsubstituted or halogenated C2-C20 alkenyl, and unsubstituted or halogenated C6-C20 aryl; Preferably, the crosslinkable group is selected from at least one of the following groups:

4. The crosslinkable polymer according to claim 1 or 2, characterized in that, The Ar2 group is selected from any one of the following groups: Where -* represents the linking site of the group; R2 and R3 are each independently selected from any one of the following: crosslinkable groups, halogens, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups. p is selected from integers from 0 to 5, and q and r are each independently selected from integers from 0 to 4.

5. The crosslinkable polymer according to claim 1 or 2, characterized in that, The Ar2 is selected from any one of the following groups, substituted or unsubstituted: Here, -* represents the linking site of a group.

6. The crosslinkable polymer according to claim 1 or 2, characterized in that, The Ar1 is selected from any one of the following groups: Where -* represents the linking site of the group; R 11 R 12 R 13 R 14 Each is independently selected from any one of the following: crosslinkable groups, halogens, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups; Z is selected from O, S, CR 15 R 16 or NAr 11 Any one of them; R 15 R 16 Each is independently selected from any one of crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C30 aryl groups; Ar 11 It is selected from any one of the following: crosslinkable groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups; L1 is selected from any one of single bond, unsubstituted or R'-substituted C6-C30 arylene, unsubstituted or R'-substituted C3-C30 heteroarylene; R' is independently selected from any one or a combination of at least two of the following: crosslinkable groups, halogens, cyano groups, nitro groups, hydroxyl groups, amino groups, C1-C20 straight-chain or branched alkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, C3-C20 cycloalkyl groups, C2-C20 heterocycloalkyl groups, C6-C30 aryl groups, C3-C30 heteroaryl groups, C3-C30 arylamino groups, and C3-C30 heteroarylamino groups; a, c, f, and g are each independently selected from integers from 0 to 4, b is selected from integers from 0 to 5, d is selected from integers from 0 to 7, and e is selected from integers from 0 to 3.

7. The crosslinkable polymer according to claim 1 or 2, characterized in that, The Ar1 is selected from any one of the following groups, whether substituted or unsubstituted: Where -* represents the linking site of the group; R 15 R 16 Each is independently selected from any one of crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, and unsubstituted or R'-substituted C6-C30 aryl groups; R 1A R 1B Each can be used independently to represent no substitution, single substitution, or the maximum permissible substitution. R 1A R 1B Each group is independently selected from any one of hydrogen, crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, and C1-C30 alkylthio groups, and is further preferred from any one of hydrogen, crosslinkable groups, C1-C20 straight-chain or branched alkyl groups, C3-C10 cycloalkyl groups, and C1-C20 alkoxy groups.

8. The crosslinkable polymer according to claim 7, characterized in that, The Ar1 is selected from any one of the following groups: -* represents the linking site of a functional group; R 15 '、R 16 Each is independently selected from any one of C1-C30 straight-chain or branched alkyl groups, unsubstituted or R'-substituted C6-C30 aryl groups; R 1C Each is independently selected from any one of hydrogen, C1-C30 straight-chain or branched alkyl, C3-C30 cycloalkyl, C1-C30 alkoxy, and C1-C30 alkylthio, and more preferably any one of hydrogen, C1-C20 straight-chain or branched alkyl, C3-C10 cycloalkyl, and C1-C20 alkoxy.

9. The crosslinkable polymer according to claim 1 or 2, characterized in that, The L is selected from any one of single-bonded, substituted or unsubstituted C6-C20 arylene groups, preferably single-bonded or phenylene.

10. The crosslinkable polymer according to claim 1 or 2, characterized in that, Each of the R1 groups is independently selected from any one of the following: crosslinkable groups, substituted or unsubstituted C1-C20 straight-chain or branched alkyl groups, substituted or unsubstituted C3-C20 cycloalkyl groups, substituted or unsubstituted C1-C20 alkoxy groups, substituted or unsubstituted C1-C20 alkylthio groups, and substituted or unsubstituted C6-C20 aryl groups; preferably, crosslinkable groups, C1-C20 straight-chain or branched alkyl groups, C3-C10 cycloalkyl groups, C1-C20 alkoxy groups, C1-C20 alkylthio groups, and substituted or unsubstituted phenyl groups. Preferably, each of the substituents in R1 is independently selected from any one of halogens, crosslinkable groups, C1-C30 straight-chain or branched alkyl groups, C3-C30 cycloalkyl groups, C1-C30 alkoxy groups, C1-C30 alkylthio groups, unsubstituted or R'-substituted C6-C30 aryl groups, and unsubstituted or R'-substituted C3-C30 heteroaryl groups. More preferably, any one of crosslinkable groups, C1-C20 straight-chain or branched alkyl groups, C3-C10 cycloalkyl groups, C1-C20 alkoxy groups, and C1-C20 alkylthio groups is selected. Preferably, each m is independently selected from an integer between 0 and 2.

11. The crosslinkable polymer according to claim 1 or 2, characterized in that, n Each group is independently selected from any one of the following groups: -* represents the linking site of a functional group; R 10 R 20 Each is independently selected from any one of C1-C30 straight-chain or branched alkyl, C3-C30 cycloalkyl, C1-C30 alkoxy, and C1-C30 alkylthio, and more preferably any one of C1-C20 straight-chain or branched alkyl, C3-C10 cycloalkyl, and C1-C20 alkoxy.

12. The crosslinkable polymer according to claim 1 or 2, characterized in that, R1 contains at least one R alkyl And / or, the substituents in Ar1 and Ar2 contain at least one R. alkyl ; The R alkyl Selected from any one of C1-C30 straight-chain or branched alkyl, C1-C30 alkoxy, C1-C30 alkylthio, and C3-C30 cycloalkyl; Preferably, R1 contains at least one R alkyl And / or, the substituents described in Ar1 contain at least one R. alkyl ; Preferably, the R alkyl It is selected from any one of C1-C20 straight-chain or branched alkyl, C1-C20 alkoxy, and C3-C10 cycloalkyl.

13. The crosslinkable polymer according to claim 1, characterized in that, The crosslinkable polymer has a structure shown in any one of A1-A12 below: Where x has the same definition as in Equation I.

14. The crosslinkable polymer according to claim 1, characterized in that, The weight-average molecular weight of the crosslinkable polymer is 30,000-500,000.

15. An application of the crosslinkable polymer as described in any one of claims 1-14, characterized in that, The crosslinkable polymer is used in organic electronic devices; Preferably, the crosslinkable polymer is used in organic electroluminescent devices; Preferably, the crosslinkable polymer serves as a hole transport material in an organic electroluminescent device.

16. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode, wherein the organic layer is prepared by at least one crosslinkable polymer as described in any one of claims 1-14; Preferably, the organic layer includes a hole transport layer, and the material used to prepare the hole transport layer includes at least one crosslinkable polymer as described in any one of claims 1-14.

17. A display device, characterized in that, The display device includes the organic electroluminescent device as described in claim 16.

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