3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation and synthesis method thereof

Abstract

The invention provides a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation and control and a synthesis method of the 3-aminopropyl polysiloxane derivative. The derivative comprises a cage type POSS (Polyhedral Oligomeric Silsesquioxane) structure, a branch type POSS structure and a network type POSS structure. According to the synthesis method, 3-aminopropyltriethoxysilane is taken as a monomer, and a cage-type, branch-type or network-type POSS structure is selectively synthesized under a fixed H < + > equivalent condition by adjusting the type of an inorganic acid catalyst and the concentration of the monomer, so that the requirements of different application scenes are met. According to the method, a high-cost functional precursor or subsequent modification and substitution reaction is not needed, various structures can be synthesized only by adjusting the catalyst type, monomer concentration and reaction conditions, the specific operation flow comprises the steps of dissolving, catalyst adding, reacting, filtering, washing, drying and the like, and the production process is simplified. The obtained product cage type POSS is applied to a composite material reinforcing agent, the branch type POSS is applied to a catalyst carrier, and the network type POSS is applied to an adhesive precursor.

Description

Technical Field

[0001] The present invention relates to the technical field of material synthesis, and in particular to a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation and a synthesis method thereof. Background Art

[0002] Polyhedral oligomeric silsesquioxane (POSS) has become a key functional material in the fields of high-end composite materials and nanocarriers due to its regular cage skeleton and excellent thermal stability. However, traditional synthesis technology has significant limitations: existing methods mainly rely on the synthesis of standardized cage structures, and it is difficult to directly obtain asymmetric branched or highly cross-linked network structures by regulating reaction conditions. In order to give POSS functional diversity, complex ligand substitution or group modification is usually required after the formation of the basic skeleton, which not only increases the process cost, but also limits the flexibility of structural design. Existing strategies often regulate the structure by changing the amount of acid or introducing mixed precursors. The synergistic effect of catalyst type and monomer concentration has not been effectively utilized, making it difficult to achieve the goal of directional synthesis of multi-configuration products by simple variable switching. This technical gap has seriously restricted the release of the potential of POSS materials in multifunctional application scenarios. Summary of the Invention

[0003] The present invention aims to provide a 3-aminopropyl polysiloxane derivative and a method for synthesizing it, based on catalyst and monomer concentration control. Specifically, a method is disclosed for selectively synthesizing three structurally distinct POSS derivatives from a single precursor (3-aminopropyltriethoxysilane) by simply manipulating the catalyst type and monomer concentration. This method addresses the lack of structural flexibility inherent in existing technologies.

[0004] This invention, for the first time, establishes a dual-variable coordinated control mechanism of "acid strength and monomer concentration," enabling the one-pot, controllable synthesis of three POSS structures under constant proton equivalent conditions. This overcomes the technical bottleneck of traditional POSS synthesis, which is limited in structural types and complex post-modification. The same precursor, 3-aminopropyltriethoxysilane, can generate a variety of structures under different reaction conditions, meeting the needs of diverse application scenarios and promoting the development of functional polymers and advanced materials.

[0005] The invention provides a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation. The derivative comprises a cage-type POSS structure, a branch-type POSS structure and / or a network-type POSS structure.

[0006] POSS is an organic-inorganic hybrid material with a silicon-oxygen backbone, typically exhibiting a regular octahedral structure. Due to its excellent thermal stability, mechanical strength, and low dielectric constant, it is widely used in polymer composites, electrical insulators, and nanomaterial platforms.

[0007] The cage structure is a typical structure of POSS, which has a regular octahedral shape. Silicon atoms are located at the vertices of the octahedron, oxygen atoms connect silicon atoms to form a skeleton, and organic groups are connected to silicon atoms. It has high symmetry and stability, can be dissolved in a variety of solvents, and is suitable for applications such as composite material reinforcement. The branch structure is an asymmetric POSS structure with a branched morphology. Compared with the cage structure, it has lower symmetry and higher reactivity, and has more organic groups exposed on the surface. It is easy to react or interact with other materials and is suitable for use as a catalyst carrier and functional surface modification material. The network structure is a highly condensed POSS structure that forms a three-dimensional network. This structure has a high cross-linking density and viscoelasticity, exhibits excellent thermal stability and mechanical properties, and can be used in adhesive precursors and anti-fouling / moisture-proof coatings.

[0008] The 3-aminopropyl polysiloxane derivatives provided by the present invention, which are regulated by catalyst and monomer concentration, include three structures. Among them, the cage-type POSS structure has high symmetry, excellent thermal stability, mechanical strength, and good dispersibility. As a composite material additive, it can improve the mechanical properties and heat resistance of the matrix material; in electrical insulation materials, it can enhance the insulation performance and mechanical stability; and as a mechanical reinforcement, it can effectively improve the mechanical properties of the composite material.

[0009] The branched POSS structure has high surface activity and exposed reactive organic groups, making it easy to interact with other materials. In the field of catalyst supports, its high surface activity and openness facilitate the dispersion of active components and improve catalyst efficiency. As a functional surface modification material, it can change the surface properties of materials to achieve specific functions. In nanoparticle binding platforms, it can interact with nanoparticles to form composite materials with unique properties.

[0010] The network-type POSS structure has high viscoelasticity and adhesion, as well as good glass transition temperature and thermal decomposition temperature; in the field of adhesives, it can enhance adhesion and temperature resistance, and improve the bonding effect; as an anti-fouling / moisture-proof coating, it can prevent the intrusion of pollutants and moisture, and extend the service life of the material; in terms of ceramic precursors, it can prepare high-performance ceramic materials suitable for high-temperature environments.

[0011] This paper focuses on an innovative synthesis method that allows for flexible control of the structure of 3-aminopropyl polysiloxane derivatives. This method not only improves the efficiency of the synthesis process but also greatly expands the application range of POSS materials, providing strong support for technological development in related fields.

[0012] The present invention provides a method for synthesizing 3-aminopropyl polysiloxane derivatives based on catalyst and monomer concentration regulation, comprising: using 3-aminopropyltriethoxysilane as a monomer, adjusting two variables, namely, the type of inorganic acid catalyst and the concentration of 3-aminopropyltriethoxysilane, to obtain a 3-aminopropyl polysiloxane derivative under a fixed H + The present invention selectively synthesizes cage-type, branch-type, or network-type POSS structures under the condition of 0.334 mol equivalent. The synthesis method of the present invention achieves precise control of POSS structure through simple and key steps. This control method not only improves the efficiency and flexibility of the synthesis process, but also reduces costs, providing a new technical solution for the field of functional polymers and advanced materials.

[0013] 3-aminopropyltriethoxysilane is a kind of important silane coupling agent, contains amino and triethoxysilane group in its structure.In the present invention, 3-aminopropyltriethoxysilane, as the basic unit of synthesizing POSS derivatives, forms silicon oxygen skeleton by hydrolysis and condensation reaction, and then builds different POSS structures.Inorganic acid catalyst plays a key role in POSS synthesis, can accelerate the carrying out of hydrolysis and condensation reaction.Different kinds of inorganic acid catalysts have different acid strengths and catalytic activities, which can affect the speed and direction of reaction, and then affect the structure formation of POSS.Hydrochloric acid and sulfuric acid are both commonly used inorganic acid catalysts, but the acid strength of sulfuric acid is higher, and catalytic activity is stronger.In the present invention, by selecting different inorganic acid catalysts, can realize the effective regulation and control to POSS structure.

[0014] The present invention reveals that as the concentration of 3-aminopropyltriethoxysilane increases, the molecular distance between the reactants gradually decreases, the arrangement freedom and mobility of the molecules in the system are significantly reduced, resulting in the condensation reaction tending to be localized and spatially cross-linked. This spatial structure evolution mechanism ultimately induces the formation of a highly condensed branched or three-dimensional network POSS structure, providing a theoretical basis for achieving precise structural control. During the POSS synthesis process, H + The total amount of H has an important influence on the reaction and the formation of the structure. + Maintaining a constant equivalent weight ensures consistent catalytic activity and reaction rate across the reaction system, allowing the formation of the POSS structure to be primarily regulated by the catalyst type and 3-aminopropyltriethoxysilane concentration. When hydrochloric acid is used as the catalyst and the 3-aminopropyltriethoxysilane concentration is 0.47 mol / L, the reaction conditions are mild, allowing the reactants to undergo sufficient hydrolysis and condensation reactions, forming a highly symmetrical cage-like structure. This structure exhibits excellent thermal stability, mechanical strength, and good solubility, and has important applications in composite reinforcements, electrical insulation materials, and other fields.

[0015] When sulfuric acid is used as a catalyst and the concentration of 3-aminopropyltriethoxysilane is 0.47 mol / L, the strong acidity of sulfuric acid accelerates the reaction rate, restricting the arrangement freedom and mobility of the reactants, leading to a localized condensation reaction and the formation of an asymmetric branched structure. The branched POSS structure has high surface activity and reactivity, and is prone to interacting with other materials, offering unique advantages in applications such as catalyst supports and functional surface modification materials.

[0016] When hydrochloric acid is used as a catalyst, but the concentration of 3-aminopropyltriethoxysilane is increased to 1.41 mol / L, the high concentration of monomers further reduces the arrangement freedom and mobility of the reactants, making the condensation reaction more localized, and ultimately forming a highly condensed network structure. The network-type POSS structure has a high cross-linking density and viscoelasticity, and exhibits good performance in the fields of adhesive precursors, antifouling / moisture-proof coatings, etc. The present invention achieves precise control of the structure of POSS derivatives by cleverly adjusting the type of inorganic acid catalyst and the concentration of 3-aminopropyltriethoxysilane, providing an efficient and flexible synthesis strategy to meet the needs of different application fields.

[0017] In the synthesis method of the present invention, when the catalyst is hydrochloric acid, a cage- or network-type structure is formed, while when it is sulfuric acid, a branch-type structure is formed. When hydrochloric acid is used as a catalyst, its acid strength is moderate, and under certain reaction conditions, the reaction rate and direction can be controlled. At relatively low 3-aminopropyltriethoxysilane concentrations (e.g., 0.47 mol / L), hydrochloric acid promotes slow and orderly hydrolysis and condensation reactions in the reaction system. This allows ample time for the reactants to undergo molecular rearrangement, thereby forming a highly symmetrical cage-type POSS structure. At this point, the monomer intermolecular distances in the reaction system are moderate, allowing the reactants to fully undergo hydrolysis and condensation reactions. Furthermore, the molecules have high freedom of arrangement and high mobility, which facilitates the formation of a regular cage-type structure. However, when the 3-aminopropyltriethoxysilane concentration is increased to a certain level (e.g., 1.41 mol / L), the monomer intermolecular distances in the reaction system decrease, reducing the freedom of arrangement and mobility of the reactants. Under the catalysis of hydrochloric acid, the condensation reaction tends to proceed locally, preventing the complete formation of the cage-type structure and ultimately forming a highly cohesive network-type structure.

[0018] Sulfuric acid, however, has a higher acid strength than hydrochloric acid and possesses stronger catalytic activity. When sulfuric acid is used as a catalyst, the reaction rate accelerates even at a low 3-aminopropyltriethoxysilane concentration (0.47 mol / L). This allows the hydrolysis and condensation reactions to proceed rapidly, limiting the full arrangement and rearrangement of the reactants and leading to a localized condensation reaction. In this case, a complete cage structure cannot be formed, and instead more branched structures are generated during the reaction, forming a dendritic POSS structure. The strong acidity of sulfuric acid causes the hydrolysis and condensation reactions of the monomer molecules to occur rapidly in the early stages of the reaction, leaving the molecules in the reaction system with insufficient time for long-range diffusion and arrangement, which in turn promotes the formation of a dendritic structure.

[0019] In the synthesis method of the present invention, a cage-type or branch-type structure is generated when the concentration of 3-aminopropyltriethoxysilane is 0.47 mol / L, and a network-type structure is generated when the concentration is 1.41 mol / L.

[0020] At lower concentrations, the distance between 3-aminopropyltriethoxysilane molecules in the reaction system is relatively large, resulting in a high degree of molecular arrangement freedom and mobility. This allows the hydrolysis and condensation reactions to proceed slowly and orderly under hydrochloric acid catalysis, giving the reactants ample time to rearrange their molecules and form a highly symmetrical cage-like POSS structure. However, under the strong acid catalysis of sulfuric acid, the reaction rate is significantly accelerated even at lower 3-aminopropyltriethoxysilane concentrations. This rapid reaction limits long-range diffusion and arrangement of the molecules, resulting in a localized condensation reaction and the formation of an asymmetric, branched structure.

[0021] When the concentration of 3-aminopropyltriethoxysilane increased to 1.41 mol / L, the molecular distances in the reaction system decreased, reducing the molecular arrangement freedom and mobility. At this high concentration, the condensation reaction tended to proceed locally, preventing the formation of a complete cage structure. Catalyzed by hydrochloric acid, this localized condensation reaction progressed further, ultimately forming a highly cohesive network structure.

[0022] Therefore, at a 3-aminopropyltriethoxysilane concentration of 0.47 mol / L, the molecular spacing between 3-aminopropyltriethoxysilane is moderate, allowing the formation of two distinct POSS structures. When hydrochloric acid is used as the catalyst, a cage-like structure is formed; when sulfuric acid is used as the catalyst, a branch-like structure is formed. At a higher concentration of 1.41 mol / L, the molecular spacing between 3-aminopropyltriethoxysilane decreases, reducing the arrangement freedom and mobility of the reactants. Local condensation reactions dominate, forming a highly cohesive network structure. By adjusting the 3-aminopropyltriethoxysilane concentration, POSS derivatives with different structures can be flexibly selected under different reaction conditions. This simple and efficient control method provides great flexibility for the synthesis and application of POSS materials.

[0023] The synthesis method of the present invention provides an efficient, flexible, and controllable pathway for the selective synthesis of 3-aminopropyl polysiloxane derivatives with diverse structural properties by simply adjusting the reaction conditions (i.e., the concentration of 3-aminopropyltriethoxysilane and the type of inorganic acid catalyst). This method not only simplifies the production process and reduces costs, but also significantly expands the application range of POSS materials, providing a new technical solution for the field of functional polymers and advanced materials.

[0024] The synthesis method of the present invention specifically comprises: S1. Dissolve 3-aminopropyltriethoxysilane in an alcohol solvent at a controlled concentration of 0.47 mol / L or 1.41 mol / L. This step is fundamental to the entire synthesis process. By dissolving 3-aminopropyltriethoxysilane in an alcohol solvent and precisely controlling its concentration, a suitable reactant environment and concentration conditions are provided for subsequent reactions, thereby influencing the structural formation of POSS. Alcohol solvents (such as methanol) can dissolve 3-aminopropyltriethoxysilane and provide a uniform reaction system, which is conducive to the hydrolysis and condensation reactions. Controlling the 3-aminopropyltriethoxysilane concentration at 0.47 mol / L or 1.41 mol / L corresponds to the conditions for forming cage / branch or network structures, respectively. This concentration control can adjust the spacing and arrangement freedom of monomer molecules in the reaction system, thereby affecting the structure of the final product.

[0025] S2. Add inorganic acid catalyst to control the H + The total amount is constant at 0.334 mol; this step is achieved by introducing an inorganic acid catalyst and maintaining H + The total amount is constant, ensuring that the reaction has sufficient catalytic activity. At the same time, by selecting different catalyst types (such as hydrochloric acid or sulfuric acid), the reaction rate and direction can be regulated, thereby affecting the structure formation of POSS. + It can promote the hydrolysis and condensation reaction of 3-aminopropyltriethoxysilane. + Maintaining a constant total amount (0.334 mol) ensures consistent catalytic activity and reaction rate across the reaction system, allowing the formation of the POSS structure to be primarily regulated by the catalyst type and 3-aminopropyltriethoxysilane concentration. The varying acid strengths of hydrochloric acid and sulfuric acid affect the reaction rate and molecular arrangement, leading to the formation of distinct POSS structures.

[0026] S3. The reaction is carried out at 20-30°C for 40-50 hours. The product is separated, washed, and dried to obtain a 3-aminopropyl polysiloxane derivative regulated by catalyst and monomer concentration. This step ensures sufficient reaction temperature and time, while separation, washing, and drying remove byproducts and unreacted materials, ultimately yielding a high-purity target product. Separation (e.g., filtration) is used to obtain a solid product; washing is used to remove residual catalyst and byproducts; and drying is used to remove solvent and moisture, ultimately yielding a high-purity target product. Reaction is carried out at a temperature range of 20-30°C for 40-50 hours, providing optimal reaction conditions for the hydrolysis and condensation reactions to proceed fully while avoiding side reactions or product degradation that could occur at excessively high temperatures. Separation (e.g., filtration) is used to obtain a solid product; washing is used to remove residual catalyst and byproducts; and drying is used to remove solvent and moisture, ultimately yielding a high-purity 3-aminopropyl polysiloxane derivative.

[0027] The present invention cleverly utilizes the synergistic effect of catalyst type and 3-aminopropyltriethoxysilane concentration to achieve precise control of POSS structure, providing a flexible and efficient synthesis method that meets the requirements of different application scenarios for POSS material structure and performance. By adjusting the reaction conditions, cage-type, branch-type or network-type POSS structures can be obtained, providing more possibilities for the application and development of POSS materials, and promoting their widespread application in the fields of composite materials, electrical insulation, catalyst supports, adhesives, etc.

[0028] In the synthesis method of the present invention, the product structure is determined by the combination of the catalyst type and the concentration of 3-aminopropyltriethoxysilane: a. When hydrochloric acid is used as the catalyst and the 3-aminopropyltriethoxysilane concentration is 0.47 mol / L, a cage-type POSS structure is obtained. The moderate acid strength of hydrochloric acid allows for slow catalytic hydrolysis and condensation reactions. The low concentration of 3-aminopropyltriethoxysilane allows for large molecular spacing and high arrangement freedom, allowing the reactants to fully rearrange into a well-organized cage-type structure. The cage-type POSS structure is symmetrical and stable, with high thermal stability, mechanical strength, and good solubility, making it widely applicable in composite materials, electrical insulation, and other fields.

[0029] b. When sulfuric acid is the catalyst and the concentration of 3-aminopropyltriethoxysilane is 0.47 mol / L, a branched POSS structure is obtained. The high acid strength of sulfuric acid rapidly catalyzes the reaction, restricting the arrangement of the reactants and leading to localized condensation reactions, resulting in an asymmetric branched structure. The branched POSS structure has high surface activity and many reactive groups, with a specific surface area of ​​≥200 m2 as determined by BET. 2 / g, with a pore size distribution of 2-50 nm. It is easy to interact with other materials and has unique advantages in the fields of catalyst supports and surface modification materials.

[0030] c. When hydrochloric acid was used as the catalyst and the 3-aminopropyltriethoxysilane concentration was 1.41 mol / L, a network-type POSS structure was obtained. The high concentration of 3-aminopropyltriethoxysilane results in small molecular spacing and low degree of arrangement freedom. Under the hydrochloric acid catalysis, the condensation reaction proceeded locally, forming a highly cohesive network structure. This network-type POSS structure exhibits high crosslink density, good viscoelasticity, and excellent thermal stability and mechanical properties, making it suitable for high-temperature applications such as adhesive precursors and antifouling coatings.

[0031] In the synthesis method of the present invention, the alcohol solvent is methanol, the concentration of hydrochloric acid in the acid catalyst is 36-38%, and the concentration of sulfuric acid is 95-98%. These specific limiting conditions ensure the controllability and stability of the synthesis method of the present invention, making it possible to selectively synthesize POSS derivatives with different structures by adjusting the type of catalyst and the concentration of 3-aminopropyltriethoxysilane.

[0032] Wherein, methanol is a kind of commonly used alcohol solvent, has good solubility, can effectively dissolve 3-aminopropyltriethoxysilane, and provides a uniform solution system for reaction. In the present invention, methanol not only serves as a reaction medium, but also can affect the rate and direction of reaction. By regulating the consumption of methanol, the concentration of 3-aminopropyltriethoxysilane can be controlled, thereby affecting the structure of the final product.

[0033] 36-38% hydrochloric acid is a commonly used concentration of hydrochloric acid solution with moderate acid strength and catalytic activity, which can effectively promote the hydrolysis and condensation reaction of 3-aminopropyltriethoxysilane. In this concentration range, hydrochloric acid can provide sufficient H + The researchers found that a 36-38% hydrochloric acid concentration and a 0.47 mol / L 3-aminopropyltriethoxysilane concentration favored the formation of a cage-type POSS structure, while a 1.41 mol / L 3-aminopropyltriethoxysilane concentration favored the formation of a network-type POSS structure.

[0034] Sulfuric acid at 95-98% concentration is a strong acid with high catalytic activity. Within this concentration range, sulfuric acid rapidly promotes the hydrolysis and condensation reactions of 3-aminopropyltriethoxysilane. Due to its strong acidity, the reaction rate is fast, limiting the arrangement freedom and mobility of the reactants. This results in a localized condensation reaction, leading to the formation of a branched POSS structure at a 3-aminopropyltriethoxysilane concentration of 0.47 mol / L.

[0035] In the synthetic system constructed by the present invention, the three structural POSS derivatives prepared exhibit significantly different interfacial behaviors and material fusion properties. The cage-type POSS structure is highly symmetrical and possesses excellent solubility and thermal stability, making it suitable for constructing uniformly dispersed nanoreinforced phases and exhibiting good reinforcement and stabilization properties in composite materials and electrical insulators. The branch-type POSS structure has strong surface activity and abundant reaction sites, making it an ideal catalyst loading platform and functional interface modification material. The network-type POSS, due to its high crosslinking density and viscoelasticity, has broad application prospects in fields such as high-temperature bonding, antifouling coatings, and ceramic precursors, demonstrating significant engineering application value. The POSS derivatives of different structures obtained by the synthetic method of the present invention play an important role in their respective application fields. The application of cage-type POSS in composite materials can significantly improve the performance of materials; the branch-type POSS provides a new approach to improving catalytic efficiency and stability in the field of catalyst supports; and the network-type POSS provides strong support for the application of materials such as adhesives in harsh environments such as high temperature and high humidity. These applications fully demonstrate the great potential of the present invention in meeting the high-performance material requirements in different fields.

[0036] The present invention provides a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation and a synthesis method thereof, by adjusting two variables, the type of inorganic acid catalyst and the concentration of 3-aminopropyltriethoxysilane, under a fixed H + The cage-type, branch-type or network-type POSS structures can be selectively synthesized under equivalent conditions, thus solving the problem of insufficient structural flexibility in the prior art.

[0037] Among them, cage-type POSS has a regular octahedral structure and excellent thermal stability and mechanical strength, and can form a highly dispersed nanoscale reinforcement phase in the composite matrix. Its silicon-oxygen skeleton provides strong chemical stability and mechanical properties, while the organic functional groups can form good interface interactions with the composite matrix. Adding cage-type POSS to composite materials can significantly improve the tensile strength, modulus, heat resistance and dimensional stability of the composite material, while reducing the water absorption and thermal expansion coefficient of the material. For example, in epoxy resin composites, the addition of cage-type POSS can effectively improve the glass transition temperature and mechanical properties of the material, making it have a wide range of application prospects in the fields of aerospace, electronic packaging, etc.

[0038] The branched POSS structure has high surface activity and abundant reactive organic groups exposed on the surface. These characteristics enable it to form strong interactions with the active components of the catalyst, providing a large number of active sites, and its multi-branched structure helps to improve the dispersibility and stability of the catalyst. As a catalyst carrier, the branched POSS can improve the activity and selectivity of the catalyst and reduce the agglomeration and loss of the catalyst. For example, in some precious metal catalysts, the branched POSS carrier can make the precious metal particles highly dispersed, increase the specific surface area of ​​the catalyst, and thus improve the efficiency and selectivity of the catalytic reaction. In addition, its good thermal stability and chemical stability can also ensure the long-term stability of the catalyst under high temperature or harsh reaction conditions.

[0039] Network-type POSS has a highly cohesive three-dimensional network structure and exhibits excellent thermal stability and mechanical properties. Its high cross-linking density and viscoelastic properties enable it to form a strong network in the adhesive, enhancing the cohesion and adhesion of the adhesive. Using network-type POSS in adhesive precursors can significantly improve the adhesive's high-temperature resistance, chemical corrosion resistance, and mechanical strength. For example, in adhesives used in some high-temperature environments, the addition of network-type POSS can enable the adhesive to maintain good adhesion and stability under high-temperature conditions, preventing the adhesive from falling off or decomposing. In addition, network-type POSS can also improve the adhesive's moisture-proof and anti-fouling properties, extending its service life.

[0040] The present invention provides a 3-aminopropyl polysiloxane derivative and its synthesis method based on catalyst and monomer concentration regulation, which simplifies the production process, eliminates the need for high-cost functional precursors or complex subsequent modification and substitution reactions, and establishes a "fixed acid equivalent + dual variable switching" platform, allowing the direct synthesis of three types of functionalized structures without post-modification, subverting the traditional "synthesis first, then modification" route. This invention reveals for the first time the synergistic mechanism of acid strength (catalyst type) and steric hindrance (monomer concentration), solving the problem of the single structure of POSS. By simply adjusting the catalyst type and monomer concentration, it is possible to achieve a fixed H +This invention establishes a modular, scalable synthetic platform for the selective synthesis of cage-, branch-, or network-type POSS structures under equivalent conditions. Its core principle is to achieve precise and selective synthesis of three POSS structures by adjusting only two key variables, catalyst type and monomer concentration, under a fixed proton equivalent. The entire process is simple and efficient, consisting of only five standard steps: dissolution, catalysis, reaction, separation, and drying, demonstrating high industrial adaptability and potential for widespread adoption. This invention utilizes the same raw material (APTES), the same reactor, and a simplified process to achieve multi-product production, significantly reducing production costs and improving efficiency. This represents a revolutionary "one-pot, multi-configuration" synthetic strategy. This invention offers structural design flexibility, enabling the selective synthesis of POSS derivatives with diverse structures by adjusting the type of inorganic acid catalyst and the concentration of 3-aminopropyltriethoxysilane. This flexibility enables the synthesis of POSS materials to meet the structural and performance requirements of diverse application scenarios, greatly expanding the scope of POSS materials' applications. At the same time, the present invention has excellent application scalability. The resulting cage-type POSS can be used in composite material reinforcing agents to improve the mechanical properties and heat resistance of the material; the branch-type POSS can be used in catalyst supports to improve catalyst efficiency and material surface properties; and the network-type POSS can be used in adhesive precursors to enhance adhesion and temperature resistance. These applications fully demonstrate the great potential of the present invention in meeting the high-performance requirements of materials in different fields. Therefore, the present invention has outstanding creative advantages in simplifying production processes, achieving structural design flexibility, and application scalability.

[0041] In summary, the present invention has the following beneficial effects: 1. The present invention constructs a synthesis strategy based on the dual variable regulation of catalyst type and monomer concentration under fixed proton equivalent conditions, and realizes the one-pot controllable synthesis of three POSS structural types (cage type, branch type, and network type) for the first time. This method has high structural selectivity and reaction predictability, simple process, mild conditions, good industrial adaptability and reproducibility; the obtained structural types are clear, and the three POSS-type materials show broad application prospects in composite materials, catalyst supports and high-performance adhesive systems, constructing a versatile organic-inorganic hybrid material platform; 2. The present invention avoids the reliance on special functional precursors or complex purification steps and can synthesize POSS materials with various structures simply by adjusting the reaction conditions, thereby improving the simplicity of the production process and the versatility of raw materials, reducing costs and improving efficiency; 3. The present invention provides a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation, including three results. Among them, the cage-type POSS can improve the mechanical properties and heat resistance of the material in the composite material reinforcing agent; the branch-type POSS is suitable as a catalyst carrier and functional surface modification material, which can improve the catalyst efficiency and material surface properties; the network-type POSS shows good performance in the fields of adhesive precursors, antifouling / moisture-proof coatings, etc., can enhance adhesion and temperature resistance, extend the service life of the material, and has significant application value and market potential; 4. The synthesis method of the present invention uses common methanol as a solvent and conventional hydrochloric acid and sulfuric acid as catalysts. The reaction can be completed at a relatively mild reaction temperature (20-30°C) and a short reaction time (40-50 hours). It is easy to operate and control, is conducive to large-scale industrial production, and reduces the requirements for equipment and operating environment. 5. Different from the traditional synthesis method of 3-aminopropyl polysiloxane derivatives, the reagents and solvents used in the reaction process of the present invention are all common chemical raw materials, which are relatively environmentally friendly, and the reaction conditions are mild, which reduces energy consumption and potential harm to the environment, and meets the requirements of sustainable development. DETAILED DESCRIPTION

[0042] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

[0043] Example 1

[0044] S1. Dissolve 20 mL of 3-aminopropyltriethoxysilane in 150 mL of methanol to a concentration of 0.47 mol / L. S2. Slowly add 28 mL of 37% hydrochloric acid as a catalyst to control the H + The total amount is constant at 0.334 mol; S3. The reaction was carried out at 25°C for 48 hours. After the reaction was completed, a white solid was obtained by filtration, washed with cold methanol, and finally dried in a vacuum drying oven at 40°C for 48 hours to obtain a product with a cage-type POSS structure.

[0045] Example 2

[0046] S1. Dissolve 20 mL of 3-aminopropyltriethoxysilane in 150 mL of methanol to a concentration of 0.47 mol / L. S2. Slowly add 9.40 mL of 95% sulfuric acid as a catalyst and 20.8 g of purified water to control the H provided by the catalyst.+ The total amount is constant at 0.334 mol; S3. The reaction was carried out at 30°C for 50 hours. After the reaction was completed, the precipitate was filtered, washed with cold methanol, and dried under vacuum at 40°C for 48 hours to obtain a branched POSS structure product.

[0047] Example 3

[0048] S1. Dissolve 20 mL of 3-aminopropyltriethoxysilane in 150 mL of methanol to a concentration of 1.41 mol / L. S2. Slowly add 28 mL of 38% hydrochloric acid as a catalyst to control the H + The total amount is constant at 0.334 mol; S3. The reaction was carried out at 20°C for 48 hours. After the reaction was completed, the sticky solid was filtered and washed with cold methanol. The solid was then dried at 40°C under vacuum for 48 hours to obtain a product with a network-type POSS structure.

[0049] Comparative Example 1 S1. Dissolve 20 mL of 3-aminopropyltriethoxysilane in 150 mL of methanol to a concentration of 0.47 mol / L. S2. Slowly add 28 mL of 37% hydrochloric acid as a catalyst to control the H + The total amount is constant at 0.334 mol; S3. The reaction was carried out at 60°C for 24 hours. After the reaction was completed, the precipitate was filtered, washed with cold methanol, and then dried at 40°C under vacuum for 48 hours to obtain a POSS structure product.

[0050] 1. Structural and physical properties analysis In order to confirm the structure and physical properties of the synthesized polyhedral oligomeric silsesquioxane derivatives, standard analytical methods such as nuclear magnetic resonance analysis (NMR), Fourier transform infrared spectroscopy (FT-IR), mass spectrometry (MS), and gel permeation chromatography (GPC) were used to analyze the products synthesized in the examples.

[0051] NMR analysis was performed using both liquid and solid-state NMR. Liquid NMR used DMSO-d6 as the solvent, while solid-state NMR measurements were performed after acid treatment. FT-IR analysis used ATR (attenuated total reflectance) to identify the primary vibrational peaks of the siloxane backbone. Mass spectrometry analysis used MALDI-TOF and ESI methods to confirm the degree of polymerization and molecular weight distribution of the structural units, respectively. GPC analysis was used to compare the average molecular weight and distribution characteristics of the polymerized samples.

[0052] Table 1 Summary of POSS structure and physicochemical properties of each group of products under different reaction conditions

[0053] Results Analysis: Examples 1, 2, and 3 of the present invention all used the same monomer (3-aminopropyltriethoxysilane, APTES) as the starting material, and the type of inorganic acid catalyst and monomer concentration (APTES concentration, mol / L) were used as reaction variables to selectively synthesize POSS derivatives with different structural characteristics. Notably, the molar number (equivalent) of the acid catalyst used in all experiments remained consistent, and the reaction trend and final structure were determined solely by the catalyst type and monomer concentration, demonstrating the reaction selectivity of the present invention. Therefore, the 3-aminopropyl polysiloxane derivative and its synthesis method, which are regulated by catalyst and monomer concentration, provided by the present invention, not only simplify the production process but also achieve flexibility in structural design and scalability in application. These derivatives have broad application prospects and are highly technologically advanced in the fields of functional polymers and advanced materials.

[0054] Example 1 POSS with a regular cage structure was synthesized by hydrochloric acid catalysis at a concentration of 0.47 mol / L 3-aminopropyltriethoxysilane. 29 Si-NMR spectra revealed a sharp single T3 peak, indicating a highly symmetrical structure with an intact silicon-oxygen backbone. Excellent thermal stability (T5% weight loss greater than 300°C) and high carbon residue (over 60% at 800°C) demonstrate its structural stability at high temperatures and resistance to decomposition. Furthermore, the product exhibits excellent solubility in a variety of solvents, including water, methanol, and dimethyl sulfoxide (DMSO). These properties make cage-type POSS suitable for composite reinforcement, improving the mechanical properties and heat resistance of composites. It can also be used as an electrical insulation material and mechanical reinforcement.

[0055] Example 2 used sulfuric acid as a catalyst and also synthesized branched POSS at a monomer concentration of 0.47 mol / L. 29 The Si-NMR spectrum shows a mixture of T2 and T3 peaks, revealing an asymmetric branched structure. Thermal stability tests indicate a T5% weight loss temperature of 258°C and a carbon residue of 38.5% at 800°C, slightly lower than that of the cage-type structure. The product is insoluble in most organic solvents but exhibits good solubility in the polar, high-boiling-point solvent N,N-dimethylformamide (DMF). This combination of structure and properties makes the branched POSS particularly suitable as a catalyst support, where its high surface activity and multiple reaction sites help improve catalytic efficiency. It also has potential applications in nanoparticle media and functional surface materials.

[0056] In Example 3, network-type POSS was successfully synthesized by increasing the monomer concentration to 1.41 mol / L and using hydrochloric acid as a catalyst. 29 The Si-NMR spectrum shows broad peaks (T3+Q4), indicating the formation of a highly cohesive network structure. The product is soluble in various solvents, including water, methanol, and DMSO, and exhibits excellent thermal stability (T5% weight loss greater than 350°C) and a high carbon residue (over 65% at 800°C). These properties of the network-type POSS make it promising for applications in adhesive precursors, moisture-proof / antifouling coatings, and ceramic precursors, particularly where high thermal stability and mechanical properties are required.

[0057] In Comparative Example 1, under the same catalyst and monomer concentrations, since the reaction temperature was increased to 60°C and the reaction time was shortened to 24 hours, a clear POSS structure was not formed and a mixed structure was obtained. 29 Si-NMR analysis revealed broad peaks spanning the T2 to T3 range, indicating an irregular structure. Thermal stability was poor (T5% weight loss at 250°C, carbon residue 30% at 800°C), and solubility in DMF was limited. This demonstrates that precise control of reaction conditions is crucial for synthesizing POSS materials with specific properties. The product of Comparative Example 1, due to its unclear structure and poor performance, struggles to find suitable high-end applications.

[0058] By adjusting the catalyst type and monomer concentration, Examples 1-3 of the present invention can synthesize POSS materials with different structures and properties to meet various application requirements. Comparative Example 1 emphasizes the importance of strictly controlling the reaction conditions to ensure the desired structure and properties.

[0059] This invention provides a 3-aminopropyl polysiloxane derivative and its synthesis method based on catalyst and monomer concentration control. Using the same monomer (APTES), a variety of POSS derivatives, including cage-type, branched, and network-type structures, can be selectively synthesized by adjusting only the catalyst type and the APTES concentration (mol / L) in the reaction system. This synthetic process is highly flexible, requiring no subsequent modification or substitution reactions; structural diversity can be achieved simply by adjusting the reaction conditions, significantly different from existing POSS technologies that focus on a single structure. Furthermore, each structure can be strategically applied in polymer composites, functional coatings, catalyst supports, adhesive precursors, and other fields based on its physical properties, solubility, aggregation characteristics, and exposed functional groups. Therefore, this invention has broad industrial applications and possesses high technical practicality and scalability.

Claims

1. A 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration regulation, characterized in that: The derivatives include a cage-type POSS structure, a branch-type POSS structure and / or a network-type POSS structure.

2. A method for synthesizing a 3-aminopropyl polysiloxane derivative based on catalyst and monomer concentration control according to claim 1, characterized in that: include: Using 3-aminopropyltriethoxysilane as monomer, the inorganic acid catalyst type and 3-aminopropyltriethoxysilane concentration were adjusted to obtain the best reaction conditions under fixed H + Cage-type, branch-type or network-type POSS structures were selectively synthesized under the conditions of 0.334 mol equivalent.

3. The synthesis method according to claim 2, characterized in that The inorganic acid catalyst includes hydrochloric acid and sulfuric acid. When the inorganic acid catalyst is hydrochloric acid, a cage-type or network-type structure is generated. When the inorganic acid catalyst is sulfuric acid, a branch-type structure is generated.

4. The synthesis method according to claim 2, characterized in that When the concentration of the 3-aminopropyltriethoxysilane is 0.47 mol / L, a cage or branch structure is generated, and when the concentration is 1.41 mol / L, a network structure is generated.

5. The synthesis method according to any one of claims 2 to 4, characterized in that Specifically include: S1. Dissolve 3-aminopropyltriethoxysilane in an alcohol solvent to control the concentration at 0.47 mol / L or 1.41 mol / L; S2. Add inorganic acid catalyst to control the H + The total amount is constant at 0.334 mol; S3. The reaction is carried out at 20-30°C for 40-50 hours, and the product is obtained by separation, washing and drying, which is a 3-aminopropyl polysiloxane derivative regulated by catalyst and monomer concentration.

6. The synthesis method according to claim 5, characterized in that The product structure is determined by the combination of catalyst type and 3-aminopropyltriethoxysilane concentration: a. When the catalyst is hydrochloric acid and the concentration of 3-aminopropyltriethoxysilane is 0.47 mol / L, a cage-type POSS structure is obtained; b. When the catalyst is sulfuric acid and the concentration of 3-aminopropyltriethoxysilane is 0.47 mol / L, a branched POSS structure is obtained; c. When the catalyst is hydrochloric acid and the concentration of 3-aminopropyltriethoxysilane is 1.41 mol / L, a network-type POSS structure is obtained.

7. The synthesis method according to claim 5, characterized in that The alcohol solvent is methanol, the concentration of hydrochloric acid in the inorganic acid catalyst is 36-38%, and the concentration of sulfuric acid is 95-98%.

8. The 3-aminopropyl polysiloxane derivative according to claim 1, characterized in that The obtained cage-type POSS is used in composite material reinforcing agents, the branch-type POSS is used in catalyst supports, and the network-type POSS is used in adhesive precursors.

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