Two-dimensional polymer block

Abstract

The invention discloses a two-dimensional polymer building block. The two-dimensional polymer building block adopts a modular structural design of'molecular core-connecting arm-reactive group ', the molecular core is selected from a unit with a two-dimensional topological structure, and the edge or surface of the molecular core is modified with a first type of reactive group and a second type of reactive group. According to the building block, by utilizing specific pairing (such as nucleophilic-electrophilic reaction, click chemistry or light / heat initiation reaction) among reactive groups, a monomolecular layer assembly with uniform thickness and a covalent cross-linked polymer building block film with high stability can be constructed on a gas-liquid interface, a liquid-liquid interface or a substrate surface through physical pre-assembly and chemical bonding. According to the preparation method, polymerization and assembly processes are decoupled, so that the problems that a traditional two-dimensional polymer is difficult to process, has many defects and is weak in interlayer binding force are effectively solved, and controllable preparation of the large-area and high-quality two-dimensional functional film is realized.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials, specifically relating to two-dimensional polymer building blocks. Background Technology

[0002] Two-dimensional polymers (2DPs) are a class of emerging materials that have attracted much attention in recent years. They possess a planar network structure with atomic-level thickness and periodicity. Utilizing the unique covalent bonding within the two-dimensional plane, 2DPs overcome the limitations of traditional materials, enabling precise customization of structures and on-demand design of functions. The excellent physicochemical properties of these materials lay a solid foundation for their groundbreaking applications in fields such as electron conduction, energy storage, molecular sieving, and catalytic reactions.

[0003] Two-dimensional polymers are generally defined as sheet-like macromolecules formed by connecting structural units (monomer molecules) in two dimensions through strong covalent bonds. More broadly, they can be interpreted as polymer molecules formed by the connection of several structural units, with a thickness less than twice the thickness of the structural units themselves. This can also be considered a generalized two-dimensional polymer because the polymerization of monomers does not spill over into a third dimension, thus exhibiting a clear dimensionality. Existing traditional two-dimensional polymers (2DPs) primarily focus on layered crystalline materials formed by periodic extension within a two-dimensional plane through strong covalent or coordination bonds, and stacking in the third dimension through van der Waals forces. Representative materials of traditional two-dimensional polymers include covalent organic frameworks (COFs). Due to their regular pore structure, large specific surface area, and designable topologies, traditional two-dimensional polymers show broad application prospects in fields such as gas adsorption and separation, catalysis, photoelectric sensing, and energy storage.

[0004] Despite the excellent potential of two-dimensional polymers in theoretical design, existing technologies still face insurmountable bottlenecks in practical preparation and application.

[0005] (1) The synthesis of traditional two-dimensional polymers (especially 2D COFs) mainly relies on thermodynamically reversible dynamic covalent bonds (such as imine bonds, borate ester bonds, etc.). While this reversibility is beneficial for repairing defects and forming long-range ordered crystal structures through "error correction mechanisms," it also leads to unsatisfactory chemical stability of the products, making them difficult to use for extended periods under conditions such as high humidity and acidity / alkalinity. Furthermore, the reversible bonding and crystallization processes place extremely high demands on reaction control, which directly affects the scalability of the product synthesis. Therefore, although COFs have been extensively studied in academia for nearly thirty years, there are currently no cases of their widespread industrial application.

[0006] (2) In the growth process of traditional two-dimensional polymers (especially 2D COFs), small molecule monomers are prepared into micron-scale crystals through bottom-up polycondensation reactions under solvothermal or interfacial conditions, which macroscopically appear as insoluble and infusible polycrystalline powder materials. Since the formation and breaking of dynamic covalent bonds connecting monomers are highly reversible, these crystals cannot be obtained into a high-ratio (>90%) monolayer two-dimensional polymer solution by adding acid-base exfoliation (ionization + dissolution strategy) or ultrasonic exfoliation (mechanical separation strategy), which greatly limits the processability of 2D COF materials and makes it impossible to obtain the membrane material form most needed in the industry, and thus apply it to mass transfer, separation, barrier and other scenarios.

[0007] To overcome the limitations of traditional two-dimensional polymers (2D COFs) in terms of chemical stability, synthetic scale-up, product processability, and mechanical properties, a new class of two-dimensional polymer materials based on irreversible chemical reactions has emerged in the prior art (US2021 / 0002426 A1 and US2025 / 0136759A1). This novel two-dimensional polymer (two-dimensional polyarylamide) mainly possesses the following technical characteristics: (1) Unlike traditional covalent organic frameworks (COFs) that rely on reversible reactions such as imine bonds and borate ester bonds to construct their skeletons, these novel two-dimensional polymers (2DPs) are prepared through irreversible polycondensation reactions between monomers. Their skeletons are connected by highly stable covalent bonds (amide bonds), thus ensuring the chemical stability of the product is similar to that of one-dimensional polyamides such as nylon and para-aramid. In practical applications, this material exhibits extremely high resistance to strong acids (such as trifluoroacetic acid) and strong mechanical forces (such as ultrasound).

[0008] (2) Such homogeneous irreversible reactions are essentially polymerization reactions in solution rather than crystallization processes. Therefore, each two-dimensional polymer is obtained through independent polymerization and is not restricted by crystals, thus preventing it from being peeled off and dispersed. In fact, only simple acidic solvents (such as trifluoroacetic acid) or strongly polar solvents (such as DMF) are needed to completely disperse the two-dimensional polymers, obtaining a true solution for subsequent processing. By introducing shear force through processing methods such as spin coating, blade coating, and slot coating, the individual two-dimensional polymers in the solution can be arranged in parallel on the substrate surface to form an ordered, dense nano-thickness thin film material. Through specific monomer design, the two-dimensional polymers grow in the same direction, and a high-density hydrogen bond network can be formed between the generated two-dimensional sheets. This structural design induces the ordered stacking of two-dimensional molecules, significantly enhancing the interlayer interaction forces.

[0009] In summary, compared with COF materials, this novel two-dimensional polymer has significant advantages in chemical and mechanical stability, and can be easily processed into nanofilm materials that are urgently needed by industry, and is expected to be truly applied beyond the laboratory.

[0010] (3) Compared with the macroscopic assemblies (thin film materials) of conventional inorganic van der Waals two-dimensional materials (graphene, hexagonal boron nitride, molybdenum disulfide, etc.), the interlayer of their nanofilms depends on strong hydrogen bonding forces (5-12 Kcal / mol) rather than weak van der Waals forces (0.5-12 Kcal / mol). Therefore, the macroscopic thin film materials assembled by these two-dimensional sheet-like molecules exhibit dense molecular arrangement and much higher mechanical properties (modulus: 12.7 GPa, strength: 488 MPa).

[0011] Although this novel two-dimensional polyarylamide has shown great advantages compared to conventional two-dimensional materials, it still has some fatal flaws that need to be addressed, mainly in the following aspects; (1) For two-dimensional polyarylamide thin film materials, although the interlayer hydrogen bonding is much stronger than the interlayer van der Waals forces, it is still close to the order of magnitude weaker than covalent bonds. At the same time, hydrogen bonding has certain directionality and saturation, and its resistance to delamination is limited. Under mechanical stress, there are still mechanical stability problems such as interlayer slip and structural disintegration. In practical applications, such films exhibit obvious brittleness and poor bending resistance at a thickness of about 100 nm, which greatly limits the actual transfer and operation, and makes such films basically lose the possibility of large-area application.

[0012] (2) The hydrogen-bonded layered two-dimensional thin films have limited ability to maintain their structure in strong acid solvents (such as trifluoroacetic acid) and strong polar aprotic solvents (such as DMF / DMSO), and will redissolve into two-dimensional polymer solutions, further limiting their application in high-performance devices.

[0013] The starting point of this patent is to design and synthesize two-dimensional polymer building blocks with special chemical structures. After forming hydrogen-bonded two-dimensional nanofilms, these blocks can be further cross-linked through various covalent cross-linking methods (thermal initiation / photoinitiation / radiation initiation, nucleophilic / electophilic / free radical / electrocyclization, etc.) to achieve highly oriented, high-density covalent cross-linking between two-dimensional polymers, ultimately yielding a highly oriented two-dimensional molecular covalent network, i.e., a two-dimensional polymer building block film. This network not only contains the original hydrogen bond network but also a highly oriented, high-density strong covalent bond network as the material framework. Therefore, it perfectly solves the solvent stability and structural stability problems of the film material, significantly improving the mechanical properties (modulus, strength, and toughness). However, obtaining high-quality, processable, and easily assembled two-dimensional polymer building blocks (the basic units of covalent cross-linking) remains a crucial technical problem that needs to be solved. Summary of the Invention

[0014] To address the problems existing in the prior art, the present invention provides a two-dimensional polymer block. The main objective of this invention is: I. This invention provides a functionalized and structurally designable two-dimensional polymer building block that overcomes the limitations of traditional two-dimensional polymers, such as structural inertness and difficulty in further reaction or assembly after synthesis. This invention pre-positions reactive first and second-class reactive groups at the molecular core, making it a universal building unit capable of self-assembly or being assembled, thus providing a material basis for constructing larger-scale ordered covalent networks.

[0015] II. This invention provides a modular building block molecular design strategy. Through the flexible combination and selection of molecular cores, connecting arms, and functional groups, it can be customized for different assembly requirements (such as nucleophilic, electrophilic, click chemistry, electrocyclization reactions, etc.). This design enables the building blocks to not only adapt to various existing two-dimensional polymer systems, but also solves the technical problem of difficulty in achieving precise modification and modular connection due to the lack of active interfaces in the prior art, significantly reducing the difficulty of subsequent assembly. Third, the two-dimensional polymer building blocks described in this invention can effectively maintain the two-dimensional planar structural characteristics of the molecular core and lock the structure through high-strength chemical bonding and / or specific physical interactions. This not only ensures the integrity of the building block itself as a basic unit, but also ensures that the two-dimensional or three-dimensional network structures subsequently constructed from it have extremely high structural stability and functional scalability, overcoming the defects of weak interlayer bonding and easy slippage and peeling of traditional two-dimensional materials.

[0016] The specific technical solution of the present invention is as follows: A two-dimensional polymer building block, the two-dimensional polymer building block comprising a molecular core and reactive groups; The reactive groups include first-class reactive groups and second-class reactive groups; The general formula of the molecular structure of the two-dimensional polymer building block is as follows: In the formula: A is the molecular core of an organic group with a valence state ≥ 2, R 1 R is a type I reactive group. 2 It is a type II reactive group; The first type of reactive group contains a first type of functional group; The second type of reactive group contains a second type of functional group; The first type of functional group and the second type of functional group have the ability to physically bond and / or chemically bond, and at least have the ability to chemically bond; The two-dimensional polymer building blocks are used to construct monolayer assemblies through physical bonding and / or chemical bonding of first-class and second-class functional groups; The thickness of the monolayer assembly is less than twice the thickness of the two-dimensional polymer block molecule.

[0017] In some embodiments of the present invention, the general molecular structural formula of the reactive group is: or In the formula: R is the connecting arm, and R' is a first-class functional group or a second-class functional group.

[0018] In some embodiments of the present invention, the first type of functional group is a covalently bonded functional group and / or a coordination bonded functional group and / or a physically bonded functional group. The second type of functional group is a covalently bonded functional group and / or a coordinate bonded functional group and / or a physically bonded functional group.

[0019] In some embodiments of the present invention, the covalently bonded functional groups include electrophilic functional groups and / or nucleophilic functional groups and / or click chemistry functional groups and / or cyclization functional groups and / or photoinitiation functional groups and / or thermal initiation functional groups. The coordination-bonded functional groups include metal central functional groups and / or complementary ligand functional groups; The physically bonded functional groups include π-system functional groups and / or charged functional groups and / or hydrophobic functional groups and / or hydrophilic functional groups and / or host-guest recognition functional groups and / or hydrogen bond donor functional groups and / or hydrogen bond acceptor functional groups.

[0020] Preferably, the electrophilic functional groups include succinimide ester group and / or isocyanate group and / or epoxy group and / or aldehyde group and / or acyl chloride group and / or carboxylic acid group and / or maleimide group and / or vinyl sulfone group and / or haloalkyl group; The nucleophilic functional groups include amino and / or thiol and / or hydroxyl and / or hydrazide and / or hydrazide and / or carboxyl group and / or sodium alkoxide and / or thiolate group; The functional groups of the click chemistry reaction include alkynyl and / or azide and / or tetraazinyl and / or norbornenyl; The cyclization functional groups include dienes and / or hydrogen dienes; The metal central functional group includes transition metal ions and / or rare earth metal ions and / or main group metal ions and / or their complexes. The complementary ligand functional groups include carboxyl groups and / or acetylaceton groups and / or benzoylmethane derivatives and / or phenoxy groups and / or alcoholoxy groups and / or amino groups and / or imino groups and / or aromatic nitrogen heterocycles and / or thiols and / or thiophenol groups and / or triphenylphosphine and / or diphenylphosphine. The π-system functional groups include carbamoyl groups and / or heterocyclic aryl groups and / or their derivatives; The hydrophobic functional groups include long-chain alkyl and / or aryl and / or perfluoroalkyl and / or polysiloxane and / or ester groups. The hydrophilic functional groups include ionic groups and / or polyether chains and / or polyol groups and / or betaine-type zwitterionic groups; The charged functional groups include quaternary ammonium salt cations and / or phosphonium salt cations and / or sulfonate anions and / or carboxylate anions and / or phosphate anions; The host-guest recognition functional groups include cyclodextrin derivatives and / or calixarene derivatives and / or adamantyl and / or ferrocene and / or organic ammonium salts; The hydrogen bond donor functional groups include amino and / or amide and / or urea and / or carboxylic acid and / or phenolic hydroxyl groups; The hydrogen bond acceptor functional groups include carbonyl and / or ether and / or ester and / or pyridine nitrogen and / or sulfonyl groups.

[0021] In some embodiments of the present invention, the first type of functional group and the second type of functional group form at least one complementary reactive functional group pair.

[0022] In some embodiments of the present invention, the molecular core is a polymeric organic group with a valence state ≥2, which is formed by the polymerization of several monomer molecules as structural units.

[0023] Preferably, the thickness of the molecular core is less than twice the thickness of its monomer molecules before polymerization.

[0024] In some embodiments of the present invention, the molecular core is a network structure with periodic topological connections.

[0025] In some embodiments of the present invention, the two-dimensional polymer block comprises at least one of the following structural units: , , , , , , , , .

[0026] In some embodiments of the present invention, the structural formula of the two-dimensional polymer block is any one of the following: , , , , , , , , , , , , , , , , , , , , , , , , , , .

[0027] In some embodiments of the present invention, the physical bonding and / or chemical bonding methods include solvent-induced assembly and / or photochemical assembly and / or thermochemical assembly and / or electrochemical assembly and / or interface assembly and / or template-assisted assembly and / or self-assembly and / or mechanochemical assembly and / or biomolecular-assisted assembly and / or chemical vapor deposition assembly and / or epitaxial growth assembly.

[0028] Preferably, the physical bonding and / or chemical bonding methods include solvent evaporation-induced assembly and / or solvent exchange-induced assembly and / or solvent polarity-controlled assembly and / or antisolvent addition-induced assembly and / or ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photoisomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase transition assembly and / or thermal polymerization-induced assembly and / or DC electrochemical assembly and / or pulsed electrochemical assembly and / or AC electrochemical assembly and / or electrochemical deposition assembly and / or electrochemical polymerization assembly and / or Langmuir-Blodgett assembly and / or liquid-liquid interface assembly and / or Gas-liquid interface assembly and / or solid-liquid interface assembly and / or hard template assembly and / or soft template assembly and / or biological template assembly and / or patterned template assembly and / or molecular self-assembly and / or supramolecular self-assembly and / or block copolymer self-assembly and / or electrostatic self-assembly and / or ultrasound-assisted assembly and / or shear-induced assembly and / or ball milling-induced assembly and / or pressure-induced assembly and / or DNA origami-guided assembly and / or enzyme-catalyzed assembly and / or protein-assisted assembly and / or carbohydrate-mediated assembly and / or low-pressure CVD assembly and / or plasma-enhanced CVD assembly and / or organometallic CVD assembly and / or atomic layer deposition-assisted assembly and / or van der Waals epitaxial assembly and / or coherent epitaxial assembly and / or step-guided assembly.

[0029] Preferably, the physical bonding and / or chemical bonding methods include photochemical assembly and / or thermochemical assembly and / or interface assembly and / or template-assisted assembly.

[0030] Preferably, the physical bonding and / or chemical bonding methods include photochemical assembly and / or thermochemical assembly.

[0031] Preferably, the physical bonding and / or chemical bonding methods include ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photoisomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase transition assembly and / or thermal polymerization-induced assembly and / or Langmuir-Blodgett assembly and / or hard template assembly and / or soft template assembly and / or biological template assembly and / or patterned template assembly.

[0032] Preferably, the physical bonding and / or chemical bonding methods include ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photo-isomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase change-induced assembly and / or thermal polymerization-induced assembly and / or Langmuir-Blodgett assembly.

[0033] The two-dimensional polymer building block described in this invention has universal applicability. The molecular core (A) not only includes a two-dimensional organic framework (such as polyarylamide or polyarylamine) formed by the polymerization of organic monomers, but also includes a sheet material with a two-dimensional topological structure that can be chemically modified at the edges.

[0034] Molecular cores (A) are mainly divided into the following three categories: (1) All-organic two-dimensional polymer cores: including but not limited to two-dimensional polyarylamides, two-dimensional polyesters, and two-dimensional polyurethanes generated by polycondensation reactions; and derivatives obtained through post-processing conversion, such as polyarylamines obtained by reduction of two-dimensional polyarylamides; and two-dimensional networks with secondary amine linkages obtained by reduction (such as reduction with NaBH4) of covalent organic frameworks (COFs) linked by imine bonds. Such reduced skeletons have higher chemical stability, and the exposed secondary amine sites can be used as natural first-class reactive groups. (2) Carbon-based two-dimensional material cores: including graphene and its derivatives (such as graphene oxide GO, fluorinated graphene), graphynylene, etc. Such cores usually have large π conjugated planes, and are chemically modified by oxygen-containing groups (such as -COOH, -OH) or defect sites on their edges or surfaces to introduce linking arms (R) and reactive groups (R). 1 / R 2 (3) Inorganic / hybrid two-dimensional material core: including layered silicates (such as montmorillonite, clay nanosheets), layered double hydroxides (LDH), transition metal chalcogenides, etc. Although the skeleton of such inorganic cores is composed of non-carbon elements, its edges are often rich in hydroxyl (-OH) or Lewis acid-base sites, which can be grafted with organic linker arms and reactive groups through silane coupling agents or coordination chemical modification, thereby giving it the assembly characteristics of organic building blocks.

[0035] This invention differs from the traditional route of directly polymerizing monomer molecules to grow large-area two-dimensional single crystals. Existing methods almost all involve one-step polymerization of small monomer molecules under specific conditions (such as interfaces or surfaces) to construct large-area two-dimensional polymer films; these methods are referred to below as direct monomer growth methods. While direct monomer growth methods have made some progress in recent years, they face fundamental and insurmountable drawbacks when constructing complex functional networks and high-quality devices.

[0036] I. Existing direct monomer growth methods face a contradiction of "reaction-crystallization" competition, leading to unavoidable and difficult-to-repair structural defects. During monomer polymerization, the formation of chemical bonds (reaction) and the arrangement of long-range ordered structures (crystallization) typically need to occur simultaneously and with high synergy. However, to achieve high crystallinity, reversible reactions are usually required to correct errors, but this often implies weaker chemical bonds, resulting in poor material stability. Conversely, to achieve high stability (e.g., forming irreversible covalent bonds), once the reaction occurs, it is difficult to correct, and any mismatches, vacancies, or topological defects remain in the crystal lattice. As the reaction region expands, accumulated defects lead to blurred domain boundaries, pore collapse, or embrittlement of mechanical properties. More importantly, once polymerization is complete, the product is often a monolithic, massive cross-linked network; any local defects cannot be removed individually like replacing parts, only leading to a decline in the overall quality of the sample.

[0037] Second, existing two-dimensional polymers, once synthesized, often exhibit highly inert chemical properties. Traditional two-dimensional polymer design focuses on the stability of the backbone; therefore, the surfaces and edges of the synthesized sheets lack effective active sites. For already prepared two-dimensional polymers, introducing active groups often relies on harsh chemical conditions such as strong acids and strong oxidants. Such processes are not only complex and have poor reaction controllability, but they also cause irreversible damage to the integrity of the two-dimensional conjugated backbone—introducing target active sites can easily lead to problems such as backbone covalent bond breakage, sheet structure collapse, and decreased crystallinity, severely impairing the original properties of the material.

[0038] Third, the lack of a modular, universal design platform leads to high R&D costs and a lack of universality. In the direct monomer growth method, each new functional requirement typically requires redesigning and synthesizing a specific monomer from the source, and re-exploring extremely sensitive polymerization conditions (temperature, concentration, catalyst, etc.). This "customized" research model is inefficient, and the polymerization kinetics of monomers with different structures vary significantly, making it difficult to build a standardized and scalable preparation process system. Furthermore, due to the lack of unified molecular connection standards and interface adaptation mechanisms, it is difficult to achieve precise heterojunction assembly and cross-layer synergistic effects between different types of two-dimensional polymers, thus limiting their large-scale application in high-end applications such as complex optoelectronic devices and multi-level separation membranes.

[0039] This invention does not address the specific problems mentioned above, but rather fundamentally reconstructs the material structure. Starting from the underlying logic of two-dimensional polymer materials and the design of primary raw materials, this invention provides a structurally designable two-dimensional polymer building block. This two-dimensional building block consists of a two-dimensional molecular core and pre-placed reactive first and second-class groups. As a generalized building unit with self-assembly or being assembled capabilities, it provides the material basis for constructing larger-scale ordered covalent networks. Specifically, these two-dimensional building blocks are first efficiently, orderly, and flexibly assembled, and then all two-dimensional monomolecules are integrated into an infinitely large, highly oriented covalently cross-linked network through independent covalent cross-linking steps. This strategy perfectly overcomes the limitations of traditional two-dimensional polymer synthesis, such as structural inertia and difficulty in further reaction or assembly, and efficiently constructs two-dimensional thin film materials with unlimited scale and adjustable thickness.

[0040] Regarding defect control and structural quality, this invention completely decouples the three processes—monomer polymerization into a two-dimensional core structure (A), assembly of two-dimensional building blocks into a film, and crosslinking between the two-dimensional building blocks—in both time and space. The two-dimensional polymer building blocks of this invention can be viewed as high-quality units that have been "pre-fabricated" and screened at the microscopic scale. Because the two-dimensional polymer building blocks are pre-synthesized under solution phase or controlled reaction conditions, the integrity of their two-dimensional core structure (A) is fully guaranteed during the assembly process. In the subsequent assembly and polymerization of the two-dimensional building blocks, this core structure (A) remains stable and unaffected by reaction conditions, thereby further improving the overall performance of the two-dimensional polymer assembly.

[0041] Regarding reactivity and assembly kinetics, this invention, through molecular design, pre-places first-type reactive groups (R groups) on the molecular core of two-dimensional polymer building blocks. 1 ) and second type reactive groups (R 2 These functional groups, like a precise mortise and tenon structure, endow the building blocks with extremely high reaction selectivity and self-assembly driving force. Two-dimensional polymer building blocks can not only form homogeneous films through their own functional groups "self-assembly," but also achieve heterogeneous assembly through group matching between different building blocks (such as nucleophilic-electrophilic, free radical, electrocyclization, click chemical pairing, etc.). This design transforms the macroscopic film construction process into a directed chemical reaction between microscopic functional groups. The introduction of connecting arms (R) provides the necessary spatial freedom, acting as a stress buffer layer, thereby achieving large-area, defect-free connections with extremely low energy barriers.

[0042] In terms of modularity and versatility, this invention constructs a class of "two-dimensional polymer building blocks." Researchers do not need to synthesize monomers from scratch for each application; they only need to select a specific two-dimensional molecular core (A) according to requirements and pair it with reactive groups (R) that can adapt to the target group or substrate. 1 / R2 This allows for the rapid assembly of the required building blocks. Based on this highly modular molecular design strategy, the specific selection and replacement of reactive groups at the ends of the building blocks endows the same molecular core with broad adaptability to different assembly microenvironments (such as aqueous / organic phase media) or reaction initiation mechanisms (such as photo / thermochemical driving). This design significantly avoids the process redundancy of repetitive monomer development for single application scenarios, thereby realizing the controllable construction and customized preparation of two-dimensional polymer materials.

[0043] The present invention provides the following reference design table, which corresponds to the modular design of the molecular core (two-dimensional polymer), first type functional group and second type functional group selected for two-dimensional polymer building blocks.

[0044] Table 1: Functional Group Matching Table Based on Table 1 above, further detailed classification is performed, resulting in the following table.

[0045] Table 2: Matching Table of Secondary Functional Groups Based on Table 2 above, we further categorize the data in detail to obtain the following table.

[0046] Table 3: Examples of Matching References for Some Tertiary (Specific) Functional Groups Based on the above tables, a verified and effective selection table (or a table of complementary / orthogonal pairings of first and second type functional groups) for two-dimensional polymer building blocks based on molecular core characteristics has been provided. Based on Tables 1-3 above, technicians can easily reproduce the modular design and construction of two-dimensional polymer building blocks with specific functions or structures, and can make the required precise selection of the pre-placed first and second type reactive groups in the building block molecules to ensure that the building blocks possess the expected self-assembly or heterogeneous assembly capabilities.

[0047] Table 4: Examples of the correspondence between molecular cores and topological structures in two-dimensional polymer building blocks The two-dimensional polymer building blocks claimed in this invention actually include a modular design of optional functional groups and a two-dimensional polymer molecular core. Typically, when designing two-dimensional polymer building blocks, the choice of the molecular core (A) is given priority, because the molecular core directly affects the upper limit of the performance of the building blocks and the final constructed two-dimensional polymer building block assembly.

[0048] To achieve long-range ordered and well-defined two-dimensional covalent networks, a planar aromatic ring core with high symmetry (such as a C3, C4, or C6 symmetric core) is preferred to establish the framework of the two-dimensional plane. Secondly, a rigid core restricts the conformational freedom of the molecules, preventing out-of-plane distortion or collapse, and ensuring that the two-dimensional polymerization reaction is strictly confined to the two-dimensional plane. The rigid core, to a certain extent, endows the material with high Young's modulus and tensile strength, enabling it to act as a robust structural unit to withstand macroscopic loads.

[0049] To achieve connectivity between two-dimensional polymer building blocks, the design of reactive groups can be based on the key characteristics of the core molecules of the two-dimensional polymer building blocks to determine in advance whether linker arms are needed and what type of linker arms are required. This improves the effective contact probability of active sites and the kinetic efficiency of the assembly reaction. The specific design is shown in Table 5. Table 5: Examples of Comparison of the Necessity of Connecting Arm Design The choice of connecting arm (R) depends on the inherent steric hindrance of the molecular core and the physicochemical requirements of the target reaction environment. When the ends and / or edges of the molecular core can directly connect to Class I / Class II functional groups, and these groups can directly and unimpededly contact each other or the target site during assembly, no connecting arm can be chosen, and they can be directly connected by chemical bonds. However, when at least one of the Class I or Class II functional groups is surrounded by the large steric hindrance framework of the molecular core, or when the reaction site is trapped due to excessive core rigidity and cannot collide effectively, a flexible or rigid connecting arm needs to be introduced to extend and position the active site, pushing it closer to the reaction site and promoting the connection of the active sites.

[0050] The reactive groups must first ensure that the first and second types of reactive groups can achieve efficient self-assembly (coupling of similar groups) or heterogeneous assembly (reaction of complementary groups) under the constraints of a given spatial configuration.

[0051] However, when the assembly chemical reaction has special characteristics (such as the need to use specific click chemistry or photochemistry) and / or the reaction microenvironment has special characteristics (such as specific interface or solvent requirements), the first / second type of reactive groups can be identified first, and then the selection and design of the connecting arms and molecular core can be carried out in reverse to construct two-dimensional polymer building blocks that meet specific process requirements.

[0052] The two-dimensional polymer building blocks claimed in this invention have universal applicability to construct various types of two-dimensional polymer building block assemblies. In summary, the two-dimensional polymer building blocks provided by this invention are modular prefabricated units based on design synthesis or selection, but they can achieve a clear structural function, that is, they can construct two-dimensional covalent networks through self-assembly or heterogeneous assembly with other building blocks. During this assembly process, the two-dimensional polymer building blocks will not produce disordered stacking and / or agglomeration in the Z-axis direction (thickness direction) under the action of the pre-placed functional groups of this invention, but will basically remain in the plane formed by the XY-axis direction of the lamellar growth for splicing and extension.

[0053] The claimed method of protection for the internal structure of the building blocks and their bonding with other building blocks includes physical bonding and / or chemical bonding, and the edges of the building blocks must contain at least a first-type reactive group and a second-type reactive group (or their complementary pair), and possess at least the ability to form chemical bonds. This is an improvement made by researchers based on the shortcomings of earlier existing technologies (such as Langmuir-Blodgett membranes and self-assembled monolayers, SAMs). Early research results showed that although two-dimensional arrangements could be formed using intermolecular hydrogen bonds or van der Waals forces, the stability of the assemblies was extremely limited, and they were very susceptible to disintegration due to thermal disturbance or solvent erosion.

[0054] Unlike earlier research results, this invention innovatively introduces highly reactive chemical groups at the edges of two-dimensional polymer building blocks, significantly improving the stability of assembly bonding (bond energy typically ≥60 kJ / mol) through covalent bonding. This invention effectively solves the technical challenge of uncontrollable reaction sites in traditional monomer direct polymerization. The two-dimensional polymer building blocks of this invention introduce connecting arm phases during the building block design stage. This structure can guide first / second type functional groups to reactive sites, and with its suitable molecular chain length, ensures sufficient connectivity and reactivity of the functional groups, thereby achieving efficient bonding connections across steric hindrance.

[0055] If the unmodified core molecule A is used directly in the reaction, the two molecules may not be able to approach each other effectively and form bonds due to rigid collisions of the core framework or steric hindrance (molecular volume effect). This invention, however, transforms the core molecule A into building blocks (R... 1 -AR 2 This allows for the formation of a stable connection. Furthermore, in cases where the volume effect is more severe, the length and rigidity / flexibility of the connecting arm R can be selectively designed to further extend the connection distance or provide stress buffering, thereby achieving smooth connection and assembly of two-dimensional polymer blocks.

[0056] The two-dimensional polymer building block design of this invention also incorporates auxiliary positioning functions. In addition to the core chemically bonded groups, if the connecting arms of the two-dimensional polymer building block also possess auxiliary groups capable of forming hydrogen bonds or π-π stacking, pre-positioning during the initial assembly stage can be achieved through physical action, allowing the building blocks to arrange themselves into a highly ordered array before the reaction. Subsequent chemical reactions then permanently lock this ordered structure in place. However, for the technical solution of this invention, priority is given to the chemical reactivity matching of the first / second type reactive groups at the edge of the building block, thereby ensuring the structural robustness of the final two-dimensional polymer building block assembly.

[0057] Assuming the goal is to construct a photoelectrically active two-dimensional covalent network, and based on the reaction mechanism design (such as Schiff base condensation), this network requires alternating interconnections of electron-rich amino nodes and electron-deficient aldehyde nodes. When designing the building blocks of this invention, pyrene, with its large conjugated plane and strong fluorescence properties, can be chosen as the molecular core A. Considering the potential steric hindrance of direct connections, amino groups are introduced at positions 1, 3, 6, and 8 via rigid linking arms R (such as phenyl groups) as first-class reactive groups R. 1 (and the second type of reactive group R) 2 At this time R 1 =R 2 Thus, 1,3,6,8-tetra(4-aminophenyl)pyrene is constructed as a specific homogeneous functional group building block.

[0058] Therefore, this invention not only provides two-dimensional polymer blocks, modular design / screening methods for blocks, and assembly methods for two-dimensional polymer blocks, but also essentially expands the application of many existing chemical substances and raw materials (as block precursors) in a completely new field of two-dimensional material manufacturing technology.

[0059] Compared with the prior art, the beneficial effects of this invention application are as follows: (1) The two-dimensional polymer building block provided by the present invention has its molecular core (A) structural integrity and orderness strictly guaranteed by synthesis before assembly, realizing the high-quality preparation of two-dimensional polymer materials and breaking through the thermodynamic limitations of the traditional monomer direct growth method.

[0060] (2) In two-dimensional polymer building blocks, the same type of molecular core can be flexibly adapted to various assembly mechanisms and assembly application environments by introducing reactive groups and / or linking arms (R) through directional modification. By constructing two-dimensional polymer building blocks, the functionalization potential and assembly controllability of two-dimensional materials are significantly improved.

[0061] (3) The two-dimensional polymer building blocks of the present invention maintain a planar configuration through rigid or semi-rigid molecular cores and are connected by high-bond-energy chemical bonds (such as covalent bonds and coordination bonds) instead of traditional van der Waals forces. This ensures the stability and mechanical strength of the two-dimensional topology and solves the problems of easy peeling and weak interlayer bonding of traditional two-dimensional materials. Attached Figure Description

[0062] Appendix Figure 1 The images show the infrared spectra of the polyaramid film before and after crosslinking.

[0063] Appendix Figure 2 This is the Raman spectrum of a two-dimensional polyamide film.

[0064] Appendix Figure 3 An atomic force microscope image of the edge of a 2DPA-HEA film, i.e., a step height diagram.

[0065] Appendix Figure 4 The infrared spectrum of the 2DPA-GLY thin film.

[0066] Appendix Figure 5 This is a schematic diagram of the synthesis of polyarylamines.

[0067] Appendix Figure 6 This is a comparison of the infrared characteristic peaks of polyarylamine and polyarylamide.

[0068] Appendix Figure 7 An atomic force microscope image of the edge of a polyarylamine film and the corresponding step height diagram.

[0069] Appendix Figure 8 The images are atomic force microscopy images of the thin film surface, including a topography (left) and a phase image (right).

[0070] Appendix Figure 9 This is the infrared spectrum of polyarylate. Detailed Implementation

[0071] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0072] In the above embodiments, the polyaramid block assembly films are all physically bonded and have no chemical bonding, while the polyaramid block films have chemical bonding.

[0073] Example 1 Table 6 lists typical structural combinations of the two-dimensional polymer building blocks described in this invention. This table is intended to specifically demonstrate how building blocks with specific reactivity can be constructed by introducing first-class and second-class functional groups based on the inherent chemical properties of the molecular core (A).

[0074] The molecular core (A) of this invention includes, but is not limited to, a two-dimensional polymer skeleton with characteristic structures such as amide bonds, urea bonds, and urethane bonds. These molecular cores are typically polymerized from multifunctional monomers, and therefore inevitably retain active sites from incomplete polymerization reactions at their edges or ends, i.e., the edge groups of the molecular core listed in the table (such as amino, carboxyl, and isocyanate groups). This invention utilizes these edge groups as reaction sites to further introduce first-type reactive groups containing first-type functional groups and second-type reactive groups containing second-type functional groups. The selection of first-type and second-type functional groups is listed in the table.

[0075] (1) Homogeneous coupling design: When the first type of functional group is the same as the second type of functional group, the building block is suitable for itself to undergo polymerization reaction (such as thermal polymerization) to construct a homogeneous two-dimensional polymer building block network.

[0076] (2) Heterogeneous complementary design: When the first type of functional group is different from the second type of functional group, the building block is designed for specific heterogeneous assembly scenarios. For example, a building block with a nucleophilic group (amino / hydroxyl) is paired with a building block with an electrophilic group (acyl chloride / epoxy) to form a stable covalent bond through condensation or addition reactions.

[0077] Table 6: Examples of molecular cores and corresponding Type I / Type II functional groups Table 7: Examples of molecular core and connecting arms Example 2 Two-dimensional polyaramid blocks (1) Synthesis of two-dimensional polyarylamide-β-alanine ethyl ester (2DPA-β-AEE): Under a nitrogen atmosphere, 22.68 g of 1,3,5-benzenetricarboxylic acid chloride (TMC) was added to a flask, followed by 600 mL of ultradry N-methylpyrrolidone (NMP). The mixture was stirred until the TMC was fully dissolved. 47.79 g of melamine (MA) was then added to the round-bottom flask and stirred. Under nitrogen protection, 180 mL of ultradry pyridine (Py) was slowly added to the system through a funnel. The reaction was carried out at room temperature and pressure with stirring for 48 h.

[0078] Under a nitrogen atmosphere, 82.9 g of β-alanine ethyl ester hydrochloride was dissolved in 300 mL of NMP and then added to the above reaction system. After stirring for 24 h, the solution was centrifuged to obtain a yellow, muddy crude product. The crude product was washed three times each with deionized water and ethanol by centrifugation. After pre-freezing in liquid nitrogen, the crude product was dried using a freeze dryer to obtain 38.63 g of yellow product powder, with a yield of 76%.

[0079] Schematic diagram of 2DPA-β-AEE synthesis: (2) Preparation of two-dimensional polyaramid block films The above 2DPA-β-AEE powder was dissolved in N,N-dimethylformamide (DMF) to form a homogeneous clear solution of a certain concentration. The solution was dropped onto a clean and flat silicon wafer surface and spin-coated at 1500 rpm for 60 s. Then, it was placed on a heating stage and annealed at 80°C for 30 min to obtain a polyarylamide building block assembly film (physical bonding only, no chemical bonding assembly).

[0080] The above-mentioned polyaramid block assembly film was heated at 280°C for 15 minutes to undergo thermal crosslinking, resulting in a two-dimensional polyaramid block film.

[0081] (3) Structural characterization High-resolution atomic force microscopy revealed that the polyarylamide product consisted of two-dimensional sheet-like molecules with a diameter of approximately 30 nm. Upon heating, cross-linking reactions gradually occurred between the molecular sheets, causing the molecules to grow larger. Infrared spectroscopy analysis confirmed that β-alanine ethyl ester in the building blocks participated in the amine-ester exchange reaction, forming imide chemical bonds. Figure 1 ), connecting two-dimensional polyaramid blocks together.

[0082] The prepared film has a thickness at the nm level and a very smooth surface. Under an atomic force microscope, the surface height undulations of the film can be seen at the nanometer level. At the same time, the phase diagram also shows a highly regular planar network structure of polyarylamide molecules, indicating that all polyarylamide molecular sheets are laid flat on the substrate surface in a highly oriented manner and can effectively self-assemble and arrange themselves.

[0083] Example 3 Referring to the method in Example 2, the monomer melamine was replaced with tetrakis(4-aminophenyl)porphyrin, and a porphyrin-based two-dimensional polymer core was prepared by reacting with TMC. Finally, a polyporphyrin block film was obtained by thermal crosslinking.

[0084] Example 4 (1) Synthesis of two-dimensional polyarylamide-2-hydroxyethyl acrylate (2DPA-HEA): Under a nitrogen atmosphere, 39.82 g of 1,3,5-benzenetricarboxylic acid chloride (TMC) was added to a flask, followed by 1000 mL of ultra-dry N-methylpyrrolidone (NMP). The mixture was stirred until the TMC was fully dissolved. 18.92 g of melamine (MA) was added to a round-bottom flask and stirred. Under nitrogen protection, 150 mL of ultra-dry pyridine (Py) was slowly added to the system through a funnel. The reaction was stirred at room temperature and pressure for 48 h. After the reaction was complete, 30 mL of deionized water was added to the reaction system. After stirring for 3.5 h, the solution was centrifuged to obtain a yellow, muddy crude product. The crude product was washed three times each with deionized water and ethanol by centrifugation. After pre-freezing in liquid nitrogen, the washed crude product was dried using a freeze dryer to obtain 38 g of yellow product powder, with a yield of 90%.

[0085] Under a nitrogen atmosphere, 15 g of the aforementioned yellow powder was added to the reactor. 230 mL of DMF was added to the reactor and stirred until fully dissolved. 20.4 mL of N,N-diisopropylethylamine (DIPEA) liquid was slowly added to the reactor while stirring continuously. 17.79 g of 2-(7-azobenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) was weighed and added to the reactor, stirred until completely dissolved. After reacting for 30 min, 12.25 mL of 2-hydroxyethyl acrylate (HEA) was added dropwise, and the reactor was sealed. After reacting at room temperature for 12 h, the reaction solution was slowly added to anhydrous diethyl ether under vigorous stirring, and the precipitate was collected. The precipitate was washed three times each with anhydrous acetonitrile, anhydrous ethanol, and deionized water by centrifugation. The crude product was pre-frozen in liquid nitrogen and then dried using a freeze dryer to obtain 11.5 g of the yellow product powder, with a yield of 77%.

[0086] Schematic diagram of 2DPA-HEA synthesis: (2) Thermal crosslinking preparation of two-dimensional polyaramid building block (2DPA-HEA) film The 2DPA-HEA powder was dissolved in DMF solvent to form a homogeneous and clear solution. This solution was dropped onto a clean, flat silicon wafer surface and spin-coated at 1000 rpm for 60 seconds. The wafer was then annealed at 80°C for 30 minutes on a heating stage to obtain an oriented polyaramid block assembly film. This film was then crosslinked by heating at 200°C for 30 minutes to obtain a crosslinked polyaramid block film.

[0087] (3) Structural characterization In the Raman spectrum ( Figure 2 The product molecule has obvious olefin double bond characteristic peaks (~1630 cm⁻¹). -1 A very smooth thin film surface can be observed under an atomic force microscope. Figure 3 This proves that the thin film is highly oriented.

[0088] Table 8: Examples of Selectable Molecular Cores and Type I / Type II Reactive Groups in Two-Dimensional Polyaramid Building Blocks Table 8 provides examples of optional first and second reactive groups for a two-dimensional polyarylamide molecular core; the selection is not limited to the listed examples. This table illustrates the flexibility in choosing the building blocks of the present invention. For the same two-dimensional polymer core with amide bonds, the choice of different reactive groups further influences the selection of the assembly reaction of the two-dimensional polyarylamide building blocks.

[0089] To avoid damage to the crystallinity, smoothness, and activity of functional groups of the film during block assembly, appropriate reactive groups can be selected during block design, and a relatively mild method can be used to achieve the assembly between blocks, ultimately obtaining a high-quality polymer film with an ordered structure.

[0090] Although the examples demonstrate spin coating, high-vacuum sublimation physical vapor deposition (PVD) or CVD assembly is equally applicable for building blocks with extremely high thermal stability (such as all-carbon skeletons).

[0091] Example 5 (1) Synthesis of two-dimensional polyarylamide building blocks (2DPA-GLY): Under a nitrogen atmosphere, 19.91 g of 1,3,5-benzenetricarboxylic acid chloride (TMC) was added to a flask, followed by 500 mL of ultra-dry N-methylpyrrolidone (NMP). The mixture was stirred until the TMC was fully dissolved. 9.46 g of melamine (MA) was added to a round-bottom flask and stirred. Under nitrogen protection, 75 mL of ultra-dry pyridine (Py) was slowly added to the system through a funnel. The reaction was stirred at room temperature and pressure for 48 h. After the reaction was complete, 10 mL of deionized water was added to the reaction system. After stirring for 3.5 h, the solution was centrifuged to obtain a yellow, muddy crude product. The crude product was washed three times each with deionized water and ethanol by centrifugation. After pre-freezing in liquid nitrogen, the washed crude product was dried using a freeze dryer to obtain 16.8 g of yellow product powder, with a yield of 80%.

[0092] Under a nitrogen atmosphere, 15 g of the aforementioned yellow powder was added to the reactor. 230 mL of DMF was added to the reactor and stirred until fully dissolved. 20.4 mL of N,N-diisopropylethylamine (DIPEA) liquid was slowly added to the reactor while stirring continuously. 17.79 g of 2-(7-azobenzotriazole)-N,N,N',N'-tetramethylurea hexafluorophosphate (HATU) was weighed and added to the reactor, stirred until completely dissolved. After reacting for 30 min, 6 mL of glycidyl ether (GLY) was added dropwise, and the reactor was sealed. After reacting at room temperature for 12 h, the reaction solution was slowly added to anhydrous diethyl ether under vigorous stirring, and the precipitate was collected. The precipitate was washed three times each with anhydrous acetonitrile, anhydrous ethanol, and deionized water by centrifugation. The crude product was pre-frozen in liquid nitrogen and then dried using a freeze dryer to obtain 10.8 g of the yellow product powder, with a yield of 72%.

[0093] (2) Preparation of two-dimensional polyaramid building block (2DPA-GLY) block film: The 2DPA-GLY powder was dissolved in DMF solvent to form a homogeneous and clear solution. This solution was dropped onto a clean, flat silicon wafer surface and spin-coated at 1000 rpm for 60 seconds. The wafer was then annealed at 80°C for 30 minutes on a heating stage to obtain an oriented polyaramid block assembly film. This film was then crosslinked by heating at 200°C for 30 minutes to obtain a polyaramid block film.

[0094] (3) Structural characterization Epoxy characteristic peak (~900cm) -1 and ~750cm -1 The gradual decrease in size as the heating temperature increases indicates that a ring-opening reaction has occurred. Figure 4 ), the glycidyl ester in the 2DPA-GLY block connects the adjacent polyarylamide blocks together.

[0095] Example 6 (1) Synthesis of polyarylamine building blocks In this embodiment, polyarylamine blocks are prepared by reduction of polyarylamine blocks. Under a nitrogen atmosphere, 2 g of the polyarylamide building blocks from Example 2 were dissolved in 10 ml of dimethyl sulfoxide (DMSO), and the solution was poured into 50 ml of dichloromethane (DCM) and stirred until homogeneous. At room temperature, 0.67 ml of trifluoromethanesulfonic anhydride was slowly added dropwise to the solution, and after stirring until homogeneous, 2.53 g of diethyl-1,4-dihydro-2,6-dimethyl-3,5-pyridine dicarboxylate was added. After stirring at room temperature for 1 h, the product was washed with ethanol and water by centrifugation, and dried under vacuum at 80 °C for 12 h to obtain 1.15 g of powder, with a yield of 80%. (The reaction of reducing polyarylamide building blocks to polyarylamine building blocks can be represented by the reaction of reducing polyarylamide to polyarylamine; a schematic diagram of the reduction reaction is shown below.) Figure 5 (As shown).

[0096] Infrared spectroscopy analysis of the product revealed a characteristic peak region of the amide bond, namely the amide carbonyl group (~1680 cm⁻¹). -1 ) and amide nitrogen hydrogen (2700-3500 cm) -1 The peak intensity decreased significantly, indicating that the amide bond was successfully reduced, yielding the structure of the polyarylamine. Figure 6 ).

[0097] (2) Preparation of polyarylamine block films The above-mentioned polyarylamine powder was dissolved in DMF and dropped onto a clean and flat silicon wafer surface. It was then spin-coated at 1500 rpm for 60 seconds, followed by annealing at 80°C for 30 minutes on a heating stage to obtain an oriented polyarylamine block assembly film. Heat treatment at 280°C for 30 minutes yielded the polyarylamine block film.

[0098] (3) Performance testing The prepared polyarylamine block film still has good surface smoothness, a thickness of about 80 nm, and surface undulations of <5 nm. Figure 7 Covalent network structures were also observed. Figure 8 This demonstrates that the synthesized polyarylamine molecules can be laid flat on the substrate surface in a highly oriented manner and can effectively self-assemble.

[0099] Table 9: Examples of Selectable Molecular Cores and Type I / Type II Reactive Groups in Two-Dimensional Polyarylamine Building Blocks When the core molecule in the two-dimensional polymer building block undergoes a certain change, the first type of reactive groups and the second type of reactive groups can be adjusted accordingly. That is, when the core group of the core molecule changes, the building block reactive groups can be flexibly selected as suitable groups to assemble the two-dimensional polymer building block.

[0100] Example 7 (1) Synthesis of two-dimensional polyarylate building blocks: Under a nitrogen atmosphere, 26.55 g of 1,3,5-benzenetricarboxylic acid chloride (TMC) was added to a flask, followed by 1000 mL of ultradry N-methylpyrrolidone (NMP). The mixture was stirred until the TMC was fully dissolved. 15.42 g of 1,3,5-triphenol was then added to a round-bottom flask and stirred. Under nitrogen protection, 100 mL of ultradry pyridine (Py) was slowly added to the system through a funnel. The reaction was carried out under ambient temperature and pressure for 48 h with stirring.

[0101] Under a nitrogen atmosphere, 10 ml of deionized water was added to the reaction system. After stirring for 24 h, the solution was centrifuged to obtain a yellow, muddy crude product. The crude product was washed three times with deionized water by centrifugation. After pre-freezing with liquid nitrogen, the crude product was dried using a freeze dryer to obtain 32.89 g of white powder, with a yield of 84%.

[0102] Schematic diagram of the synthesis of two-dimensional polyarylate building blocks: (2) Preparation of polyarylate building block films: Two-dimensional polyarylate was dissolved in NMP to form a homogeneous clear solution of a certain concentration. The solution was dropped onto a clean and flat silicon wafer surface and spin-coated at 1500 rpm for 60 s. Then, it was placed on a heating stage and annealed at 100°C for 30 min to obtain an oriented polyarylate block assembly film. The film was then heat-treated at 260°C for 20 min to obtain a polyarylate block film.

[0103] (3) Structural characterization In the infrared spectrum of polyarylates at 1700 cm⁻¹ -1 The presence of a strong ester group peak nearby indicates that the two monomers successfully reacted to obtain the polyarylate. Figure 9 ).

[0104] Unlike the polyamide / polyamine systems in Examples 1-6, this example constructs a two-dimensional polyester molecular core, demonstrating that the molecular core A described in this invention encompasses a variety of condensation polymer backbones.

[0105] Example 8 (1) Synthesis of two-dimensional polyarylate building blocks: Under a nitrogen atmosphere, 26.55 g of 1,3,5-benzenetricarboxylic acid chloride (TMC) was added to a flask, followed by 1000 mL of ultradry N-methylpyrrolidone (NMP). The mixture was stirred until the TMC was fully dissolved. 15.42 g of 1,3,5-triphenol was then added to a round-bottom flask and stirred. Under nitrogen protection, 100 mL of ultradry pyridine (Py) was slowly added to the system through a funnel. The reaction was carried out under ambient temperature and pressure for 48 h with stirring.

[0106] Under a nitrogen atmosphere, 41.4 g of β-alanine ethyl ester hydrochloride was dissolved in 300 mL of NMP and then added to the above reaction system. After stirring for 24 h, the solution was centrifuged to obtain a yellow, muddy crude product. The crude product was washed three times each with deionized water and ethanol by centrifugation. After pre-freezing in liquid nitrogen, the crude product was dried using a freeze dryer to obtain 29.33 g of yellow product powder, with a yield of 72%.

[0107] (2) Preparation of polyarylate building block films: Two-dimensional polyarylate was dissolved in NMP to form a homogeneous clear solution of a certain concentration. The solution was dropped onto a clean and flat silicon wafer surface and spin-coated at 2000 rpm for 60 s. Then, it was placed on a heating stage and annealed at 100°C for 30 min to obtain an oriented polyarylate block assembly film. The film was then heat-treated at 260°C for 20 min to obtain a polyarylate block film.

[0108] In the above embodiments, the two-dimensional polymer block assembly films are either all physically bonded and have no chemical bonding, or the two-dimensional polymer block films have chemical bonding.

[0109] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, and processes discussed in this application can be alternated, modified, combined, or deleted; furthermore, other steps, measures, and schemes in the various operations, methods, and processes discussed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted; furthermore, the steps, measures, and schemes in the prior art that are similar to those disclosed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. The above-described embodiments are merely illustrative of several implementation methods of this disclosure, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of the patent for the embodiments of this disclosure. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the embodiments of this disclosure, and these all fall within the protection scope of the embodiments of this disclosure. Therefore, the protection scope of the embodiments of this disclosure should be determined by the appended claims. As described above, although the present invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the present invention itself. Various changes in form and detail can be made without departing from the spirit and scope of the present invention as defined in the appended claims.

[0110] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A two-dimensional polymer building block, characterized in that, The two-dimensional polymer building block includes a molecular core and reactive groups; The reactive groups include first-class reactive groups and second-class reactive groups; The general formula of the molecular structure of the two-dimensional polymer building block is as follows: In the formula: A is the molecular core of an organic group with a valence state ≥ 2, R 1 R is a type I reactive group. 2 It is a type II reactive group; The first type of reactive group contains a first type of functional group; The second type of reactive group contains a second type of functional group; The first type of functional group and the second type of functional group have the ability to physically bond and / or chemically bond, and at least have the ability to chemically bond; The two-dimensional polymer building blocks are used to construct monolayer assemblies through physical bonding and / or chemical bonding of first-class and second-class functional groups; The thickness of the monolayer assembly is less than twice the thickness of the two-dimensional polymer block molecule; Preferably, the general molecular structural formula of the reactive group is: or In the formula: R is the connecting arm, and R' is a first-class functional group or a second-class functional group.

2. The two-dimensional polymer block according to claim 1, characterized in that, The first type of functional group is a covalently bonded functional group and / or a coordinate bonded functional group and / or a physically bonded functional group; The second type of functional group is a covalently bonded functional group and / or a coordinate bonded functional group and / or a physically bonded functional group.

3. The two-dimensional polymer block according to claim 2, characterized in that, The covalently bonded functional groups include electrophilic functional groups and / or nucleophilic functional groups and / or click chemistry functional groups and / or cyclization functional groups and / or photoinitiation functional groups and / or thermal initiation functional groups; The coordination-bonded functional groups include metal central functional groups and / or complementary ligand functional groups; The physically bonded functional groups include π-system functional groups and / or charged functional groups and / or hydrophobic functional groups and / or hydrophilic functional groups and / or host-guest recognition functional groups and / or hydrogen bond donor functional groups and / or hydrogen bond acceptor functional groups. Preferably, the electrophilic functional groups include succinimide ester group and / or isocyanate group and / or epoxy group and / or aldehyde group and / or acyl chloride group and / or carboxylic acid group and / or maleimide group and / or vinyl sulfone group and / or haloalkyl group; The nucleophilic functional groups include amino and / or thiol and / or hydroxyl and / or hydrazide and / or hydrazide and / or carboxyl group and / or sodium alkoxide and / or thiolate group; The functional groups of the click chemistry reaction include alkynyl and / or azide and / or tetraazinyl and / or norbornenyl; The cyclization functional groups include dienes and / or hydrogen dienes; The metal central functional group includes transition metal ions and / or rare earth metal ions and / or main group metal ions and / or their complexes. The complementary ligand functional groups include carboxyl groups and / or acetylaceton groups and / or benzoylmethane derivatives and / or phenoxy groups and / or alcoholoxy groups and / or amino groups and / or imino groups and / or aromatic nitrogen heterocycles and / or thiols and / or thiophenol groups and / or triphenylphosphine and / or diphenylphosphine. The π-system functional groups include carbamoyl groups and / or heterocyclic aryl groups and / or their derivatives; The hydrophobic functional groups include long-chain alkyl and / or aryl and / or perfluoroalkyl and / or polysiloxane and / or ester groups. The hydrophilic functional groups include ionic groups and / or polyether chains and / or polyol groups and / or betaine-type zwitterionic groups; The charged functional groups include quaternary ammonium salt cations and / or phosphonium salt cations and / or sulfonate anions and / or carboxylate anions and / or phosphate anions; The host-guest recognition functional groups include cyclodextrin derivatives and / or calixarene derivatives and / or adamantyl and / or ferrocene and / or organic ammonium salts; The hydrogen bond donor functional groups include amino and / or amide and / or urea and / or carboxylic acid and / or phenolic hydroxyl groups; The hydrogen bond acceptor functional groups include carbonyl and / or ether and / or ester and / or pyridine nitrogen and / or sulfonyl groups.

4. The two-dimensional polymer block according to claim 3, characterized in that, The first type of functional group and the second type of functional group form at least one complementary reactive functional group pair.

5. The two-dimensional polymer block according to claim 1, characterized in that, The molecular core is a polymeric organic group with a valence state ≥2, which is formed by the polymerization of several monomer molecules as structural units. Preferably, the thickness of the molecular core is less than twice the thickness of its monomer molecules before polymerization.

6. The two-dimensional polymer block according to claim 5, characterized in that, The molecular core is a network structure with periodic topological connections.

7. The two-dimensional polymer block according to claim 1, characterized in that, The two-dimensional polymer block comprises at least one of the following structural units: 、 、 、 、 、 、 、 、 。 8. The two-dimensional polymer block according to claim 1 or 7, characterized in that, The structural formula of the two-dimensional polymer block is any one of the following: 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 。 9. The two-dimensional polymer block according to claim 1, characterized in that, The physical bonding and / or chemical bonding methods include solvent-induced assembly and / or photochemical assembly and / or thermochemical assembly and / or electrochemical assembly and / or interface assembly and / or template-assisted assembly and / or self-assembly and / or mechanochemical assembly and / or biomolecular-assisted assembly and / or chemical vapor deposition assembly and / or epitaxial growth assembly. Preferably, the physical bonding and / or chemical bonding methods include solvent evaporation-induced assembly and / or solvent exchange-induced assembly and / or solvent polarity-controlled assembly and / or antisolvent addition-induced assembly and / or ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photoisomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase transition assembly and / or thermal polymerization-induced assembly and / or DC electrochemical assembly and / or pulsed electrochemical assembly and / or AC electrochemical assembly and / or electrochemical deposition assembly and / or electrochemical polymerization assembly and / or Langmuir-Blodgett assembly and / or liquid-liquid interface assembly and / or Gas-liquid interface assembly and / or solid-liquid interface assembly and / or hard template assembly and / or soft template assembly and / or biological template assembly and / or patterned template assembly and / or molecular self-assembly and / or supramolecular self-assembly and / or block copolymer self-assembly and / or electrostatic self-assembly and / or ultrasound-assisted assembly and / or shear-induced assembly and / or ball milling-induced assembly and / or pressure-induced assembly and / or DNA origami-guided assembly and / or enzyme-catalyzed assembly and / or protein-assisted assembly and / or carbohydrate-mediated assembly and / or low-pressure CVD assembly and / or plasma-enhanced CVD assembly and / or organometallic CVD assembly and / or atomic layer deposition-assisted assembly and / or van der Waals epitaxial assembly and / or coherent epitaxial assembly and / or step-guided assembly.

10. The two-dimensional polymer block according to claim 1 or 9, characterized in that, The physical bonding and / or chemical bonding methods include photochemical assembly and / or thermochemical assembly and / or interface assembly and / or template-assisted assembly; preferably, the physical bonding and / or chemical bonding methods include photochemical assembly and / or thermochemical assembly. Further preferably, the physical bonding and / or chemical bonding methods include ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photo-isomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase transition-induced assembly and / or thermal polymerization-induced assembly and / or Langmuir-Blodgett assembly and / or hard template assembly and / or soft template assembly and / or biological template assembly and / or patterned template assembly; Most preferably, the method of physical bonding and / or chemical bonding includes ultraviolet light-induced assembly and / or visible light-induced assembly and / or infrared light-induced assembly and / or photo-isomerization-induced assembly and / or photopolymerization-induced assembly and / or thermal treatment assembly and / or thermal gradient-induced assembly and / or thermally induced phase change-induced assembly and / or thermal polymerization-induced assembly and / or Langmuir-Blodgett assembly.

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