Composite silicone rubber material, preparation method thereof and fiber-reinforced silicone rubber

Abstract

The invention provides a composite silicone rubber material, a preparation method thereof and fiber-reinforced silicone rubber, and relates to the technical field of silicone rubber. The composite silicone rubber material provided by the invention comprises silicone rubber-based rubber and a modified filler dispersed in the silicone rubber-based rubber, wherein the modified filler is prepared by carrying out surface modification on a solid filler by using a triazine ring functionalized silane coupling agent. The triazine ring functionalized silane coupling agent is used for carrying out surface modification on the solid filler to promote the solid filler to form a star-shaped or network structure with uniform spacing, so that the interaction between the solid filler can be obviously improved, and the dispersity and spacing consistency of the modified filler dispersed in the composite silicone rubber material are ensured; therefore, the modified filler after vulcanization can construct a high-strength, high-density and high-stability interface layer in the silicone rubber, and the mechanical property, durability and heat resistance of the silicone rubber composite material are comprehensively improved.

Description

Technical Field

[0001] This invention relates to the field of silicone rubber technology, and in particular to a composite silicone rubber material and its preparation method, as well as fiber-reinforced silicone rubber. Background Technology

[0002] Many complex sets of equipment have core functional components that are assembled by layering multiple shell or tubular structures. However, due to differences in the thermal expansion coefficients of the materials used in each structure, as well as due to poor machining and changes in the operating environment, the gaps between the structures are constantly changing, resulting in vibration and noise, which affects the working quality and service life of the equipment.

[0003] During equipment installation, damping elements are usually installed at the gaps between various structures to provide support and shock absorption, fill gaps, compensate for machining defects, and adjust for gap changes. This ensures that each layer of the structure is in a "tightly" state (integrated positioning, preventing rotation) without the "overload" damage of the strong structure crushing the weak structure, thereby improving the overall reliability, safety, and service life of the equipment.

[0004] Therefore, the reliability of the damping element itself is particularly important. Silicone rubber has been widely used in the field of precision equipment due to its advantages such as high and low temperature elasticity, excellent radiation resistance, aging resistance, excellent compatibility, good resilience, and strong damping performance. However, silicone rubber molecules have low polarity and weak intermolecular forces, and its physical and mechanical properties (modulus and strength) at room temperature are much lower than those of other rubber materials, making it a typical low-modulus, low-strength rubber.

[0005] Currently, to improve the modulus and strength of silicone rubber materials, the main approach is to partially replace the flexible, low-cohesive-energy -Si-O-Si- links with phenylene or phenylene ethers to develop phenylene or phenylene ether silicone rubber. However, while this method improves the modulus and strength of silicone rubber, it significantly reduces resilience and temperature resistance (-60~300℃). Therefore, there is an urgent need to provide a solution to address these issues. Summary of the Invention

[0006] The purpose of this invention is to provide a composite silicone rubber material and its preparation method, as well as fiber-reinforced silicone rubber.

[0007] In a first aspect, the present invention provides a composite silicone rubber material comprising a silicone rubber base and a modified filler dispersed within the silicone rubber base, wherein the modified filler is prepared by surface modification of a solid filler with a triazine cyclofunctionalized silane coupling agent.

[0008] The composite silicone rubber material provided by this invention utilizes a triazine cyclofunctionalized silane coupling agent to modify the surface of solid fillers, promoting the formation of a uniformly spaced star-shaped or network structure between the solid fillers. This significantly improves the interaction between the solid fillers, ensuring the dispersion and spacing consistency of the modified fillers within the composite silicone rubber material. Thus, after vulcanization, the modified fillers can construct a high-strength, high-density, and high-stability interface layer within the silicone rubber, comprehensively improving the mechanical properties, durability, and heat resistance of the silicone rubber composite material.

[0009] Optionally, the composite silicone rubber material includes 10wt%-30wt% of the modified filler.

[0010] Optionally, the solid filler includes nanoparticles and chopped fibers.

[0011] Optionally, the nanoparticles include one of fumed silica, precipitated silica, nano-alumina, and nano-calcium carbonate.

[0012] Optionally, the chopped fibers include one of cellulose nanocrystals, silicon nitride nanocrystals, silicon carbide nanocrystals, and silicon oxynitride nanocrystals.

[0013] Optionally, the average particle size of the nanoparticles is less than or equal to 200 nm.

[0014] Optionally, the diameter of the chopped fibers is less than or equal to 500 nm.

[0015] Optionally, the aspect ratio of the chopped fibers is greater than or equal to 20 and less than or equal to 100.

[0016] Optionally, the solid filler comprises nanoparticles and chopped fibers in a mass ratio of (1-2):(0.01-1).

[0017] Optionally, the silicone rubber base includes one of vinyl silicone rubber, methyl vinyl silicone rubber, and methyl phenyl vinyl silicone rubber.

[0018] Optionally, the preparation method of the triazine ring functionalized silane coupling agent includes: reacting a triazine ring compound with a silane coupling agent in a liquid environment with pH=5-6 and 0℃-5℃, and then separating the triazine ring functionalized silane coupling agent.

[0019] Optionally, the triazine ring compound includes one of cyanuric chloride, cyanuric fluorochlorotri ...

[0020] Optionally, the silane coupling agent includes one of KH550, KH792, and KH892.

[0021] Optionally, the liquid environment includes one of acetonitrile, acetone, and chloroform.

[0022] Optionally, the concentration of the reactant in the liquid environment is 5%-30%, and the reactant consists of a triazine ring compound and a silane coupling agent.

[0023] Optionally, the mass fraction of the triazine ring compound in the reactants is 35%-75%.

[0024] Optionally, the mass fraction of the silane coupling agent in the reactants is 25%-65%.

[0025] Optionally, the triazine ring compound is separated after reacting with a silane coupling agent for 1-3 hours.

[0026] Optionally, the liquid environment is removed after the reaction to obtain a triazine cyclofunctionalized silane coupling agent.

[0027] Optionally, the method for removing the liquid environment includes rotary distillation.

[0028] Optionally, when the modified filler is obtained by surface modification of the solid filler with a triazine cyclofunctionalized silane coupling agent, the process includes: wetting and modifying the solid filler in an active solution and then separating the modified filler; wherein the active solute in the active solution includes at least a triazine cyclofunctionalized silane coupling agent.

[0029] Optionally, the solid filler in the active solution has a solid-liquid ratio of 0.02 g / mL to 0.05 g / mL.

[0030] Optionally, the mass concentration of the triazine cyclofunctionalized silane coupling agent in the active solution is 2%-10%.

[0031] Optionally, the solvent in the active solution includes one of ethyl acetate, ethanol, isopropanol, and tetrahydrofuran.

[0032] Optionally, the solid filler can be modified by impregnating it in an active solution for 1-3 hours.

[0033] Optionally, the modification can be carried out by impregnation at 20℃-30℃.

[0034] Optionally, the solid filler is modified by impregnation in an active solution under physical mixing, wherein the physical mixing includes stirring and ultrasonication.

[0035] Optionally, when the solid filler comprises nanoparticles and chopped fibers, the impregnation modification includes: mixing the nanoparticles and chopped fibers, impregnating and modifying them in an active solution, and then separating them to obtain the modified filler; or, impregnating and modifying the nanoparticles and chopped fibers separately in an active solution, separating them, and then combining them to obtain the modified filler.

[0036] Optionally, the silicone rubber base may also contain functional additives.

[0037] Optionally, the composite silicone rubber material includes 5wt%-40wt% of functional additives.

[0038] Optionally, the functional additives include crosslinking agents, catalysts, and inhibitors.

[0039] Optionally, the crosslinking agent includes a hydrogen-containing silicone oil crosslinking agent.

[0040] Optionally, the catalyst includes a cassiterite catalyst or a platinum catalyst.

[0041] Optionally, the inhibitor includes butynol inhibitors.

[0042] Optionally, the functional additive includes 5wt%-15wt% of a catalyst.

[0043] Optionally, the functional adjuvant includes 5wt%-15wt% of an inhibitor.

[0044] Optionally, the functional additive includes 70wt%-90wt% of a crosslinking agent.

[0045] Optionally, the preparation method of the hydrogen-containing silicone oil crosslinking agent includes: condensing and dehydrating an acid anhydride and an amino monomer to form an imide-siloxane oligomer, and then, under the action of an accelerator, reacting the imide-siloxane oligomer with a hydrogen-containing silicon monomer to generate a hydrogen-containing silicone oil crosslinking agent.

[0046] Optionally, the acid anhydride includes one of fluorenone dianhydride and triazine cyclothioether dianhydride; Optionally, the acid anhydride comprises 20 mol%-80 mol% fluorenone dianhydride; Optionally, the acid anhydride comprises 20 mol%-80 mol% of triazine cyclothioether dianhydride; Optionally, the amino monomer includes one of 1,3-bis(3-aminopropyl)tetramethyldisiloxane and 4,6-dichloro-1,3,5-triazinecyclo-2-amine; Optionally, the amino monomer comprises 20 mol%-80 mol% of 1,3-bis(3-aminopropyl)tetramethyldisiloxane; Optionally, the amino monomer comprises 20 mol%-80 mol% of 4,6-dichloro-1,3,5-triazine-2-amine; Optionally, the promoter includes one of a platinum catalyst, a caster catalyst, and a spanning catalyst; Optionally, the hydrogen-containing silicon monomer includes one of methylhydrocyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyldihydrodisiloxane; Optionally, the molar ratio of the acid anhydride to the amino monomer is (0.8-1.2):1; Optionally, the molar ratio of the hydrogen-containing silicon monomer to the imide-siloxane oligomer is 1:(2-4); Optionally, the molar ratio of the accelerator to the hydrogen-containing silicon monomer is (0.005-0.01):100; Optionally, the acid anhydride and the amino monomer are condensed at -4℃ to 4℃ to generate an imide-siloxane intermediate; Optionally, the acid anhydride and amino monomer are condensed and then dehydrated to form a ring at 150℃-250℃. Optionally, the chain extension reaction is carried out at 80℃-120℃; Optionally, the chain extension reaction can be carried out for 12-24 hours.

[0047] In a second aspect, the present invention also provides a method for preparing any of the above-mentioned optional composite silicone rubber materials, comprising: surface modification of a solid filler using a triazine cyclofunctionalized silane coupling agent to obtain a modified filler; and dispersing the modified filler in a silicone rubber base to obtain a composite silicone rubber material.

[0048] Optionally, a composite silicone rubber material can be prepared by dispersing modified fillers and functional additives in a silicone rubber base.

[0049] Thirdly, the present invention also provides a reinforced silicone rubber matrix obtained by adding vulcanization of any of the above-mentioned optional composite silicone rubber materials.

[0050] Fourthly, the present invention also provides a method for preparing fiber-reinforced silicone rubber, comprising: impregnating a fiber layer in a composite silicone rubber material and then separating it; and performing addition vulcanization at 80°C-120°C to obtain fiber-reinforced silicone rubber; wherein the composite silicone rubber material is any of the above-mentioned optional composite silicone rubber materials.

[0051] Optionally, the fibers in the fiber layer include one of high-modulus quartz fibers, carbon fibers, boron fibers, polyimide, and aramid fibers.

[0052] Fifthly, the present invention also provides a fiber-reinforced silicone rubber prepared by the above-mentioned method for preparing fiber-reinforced silicone rubber. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the structure of a composite silicone rubber material provided by the present invention; Figure 2 This is a schematic flowchart of a method for preparing a composite silicone rubber material provided by the present invention.

[0054] Explanation of reference numerals in the attached figures: 1. Silicone rubber base; 2. Modified granules; 3. Modified fibers. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this invention pertains.

[0056] This invention provides a composite silicone rubber material, comprising a silicone rubber base and a modified filler dispersed within the silicone rubber base. The modified filler is prepared by surface modification of a solid filler with a triazine cyclofunctionalized silane coupling agent. In effect, surface modification of the solid filler improves its dispersibility and compatibility within the silicone rubber base.

[0057] Specifically, by using triazine ring-functionalized silane coupling agents for surface modification, rigid and symmetrical triazine rings can be grafted onto the surface of solid fillers. Due to the steric hindrance effect of triazine rings, the agglomeration and sedimentation of solid fillers can be further avoided after grafting onto the surface of solid fillers. At the same time, it helps the modified fillers to oriented and align within the silicone rubber matrix, thereby forming a star-shaped or network topology with uniform spacing in three-dimensional space.

[0058] In fact, uniformly distributed modified fillers, after addition vulcanization molding of silicone rubber materials, can form a continuous reinforcing network that can efficiently transfer and disperse stress, greatly improving the overall tensile strength and elastic modulus of silicone rubber. Simultaneously, the stable interface layer between the filler network and silicone rubber can prevent the growth of microcracks, thereby improving the overall fatigue resistance of silicone rubber. Furthermore, the rigid triazine ring itself has good heat resistance, thus effectively maintaining the interfacial bonding between the filler network and silicone rubber at high temperatures, thereby improving the overall heat aging resistance of silicone rubber.

[0059] In some embodiments, the composite silicone rubber material includes 10wt%-30wt% of modified filler. In practice, when the content of modified filler is too low, it is difficult to form a stable reinforcing network within the silicone rubber, while when the content of modified filler is too high, filler agglomeration and sedimentation will inevitably occur, which will negatively affect the mechanical properties and mechanical strength of the silicone rubber.

[0060] Specifically, the solid fillers used include nanoparticles and chopped fibers. In fact, by surface-modifying the nanoparticles and chopped fibers and dispersing them in silicone rubber, the modified particles can act as nodes that are uniformly dispersed within the silicone rubber, while the modified fibers can act as a skeleton to connect the nanoparticles, thereby forming a lattice-reinforced network in the silicone rubber. This is beneficial for improving the mechanical properties and strength of the silicone rubber.

[0061] In some embodiments, the nanoparticles used include one of fumed silica, precipitated silica, nano-alumina, and nano-calcium carbonate, and the chopped fibers used include one of cellulose nanocrystals, silicon nitride nanowhiskers, silicon carbide nanowhiskers, and silicon oxynitride nanowhiskers. Further, the average particle size of the nanoparticles is less than or equal to 200 nm, and the diameter of the chopped fibers is less than or equal to 50 nm, with an aspect ratio greater than or equal to 20 and less than or equal to 100. Specifically, the solid filler may include nanoparticles and chopped fibers in a mass ratio of (1-2):(0.01-1).

[0062] Specifically, this invention also provides a method for preparing a triazine ring-functionalized silane coupling agent, comprising: reacting a triazine ring compound with a silane coupling agent in a liquid environment at pH 5-6 and 0℃-5℃, followed by separation to obtain the triazine ring-functionalized silane coupling agent. In fact, during the reaction, the active group on the triazine ring compound is nucleophilically replaced by the amino group in the silane coupling agent, thereby obtaining a silane coupling agent with a triazine ring. Further, the triazine ring compound used includes one of cyanuric chloride (CAS: 108-77-0), cyanuric fluorochlorotrichlorofluoro ...

[0063] In fact, cyanuric chloride, cyanuric fluorochlorotri ...

[0064] In some embodiments, the liquid environment used in preparing the triazine ring-functionalized silane coupling agent includes one of acetonitrile, acetone, and chloroform. In practice, the liquid environment must be capable of completely dissolving the triazine ring compound and the silane coupling agent without causing a reaction. Furthermore, before the reaction, the liquid environment is pre-cooled at 0°C-5°C, and then the triazine ring compound and the silane coupling agent are added and mechanically mixed. Preferably, the mechanical mixing method can be conventional solubilizing methods in the art, such as stirring or ultrasound.

[0065] In some embodiments, the concentration of the reactants in the liquid environment is 5%-30%, and the mass fraction of the triazine ring compound in the reactants is 35%-75%, while the mass fraction of the silane coupling agent is 25%-65%. Clearly, the reactants consist of a triazine ring compound and a silane coupling agent. Furthermore, ultrasonication, stirring, or other methods can be applied during the reaction to improve reaction efficiency.

[0066] In some embodiments, the triazine ring compound and the silane coupling agent are mixed and reacted in a liquid environment for 1-3 hours, and then the liquid environment is removed to obtain the triazine ring-functionalized silane coupling agent. In practice, one reactant can be added in excess during the mixing reaction to promote the reaction and increase the product yield. Preferably, a reactant with a lower boiling point is selected in excess, and after the reaction is complete, excess and unreacted reactants can be removed by rotary distillation to obtain the triazine ring-functionalized silane coupling agent.

[0067] Specifically, when preparing modified fillers by surface modification of solid fillers with triazine cyclofunctionalized silane coupling agents, the process includes: impregnating and modifying the solid filler in an active solution followed by separation to obtain the modified filler, wherein the active solute in the active solution includes at least the triazine cyclofunctionalized silane coupling agent. In practice, during the impregnation and modification process, the triazine cyclofunctionalized silane coupling agent is grafted onto the surface of the solid filler, and the steric hindrance effect of the triazine ring end groups improves the dispersibility of the modified filler.

[0068] In some embodiments, the solid-liquid ratio of the solid filler in the active solution is 0.02 g / mL to 0.05 g / mL, and the mass concentration of the triazine cyclofunctionalized silane coupling agent in the active solution is 2% to 10%. In fact, by impregnating and modifying the solid filler in the active solution, it is beneficial for the triazine cyclofunctionalized silane coupling agent to uniformly modify the surface of the solid filler. Further, the solvent in the active solution includes one of ethyl acetate, ethanol, isopropanol, and tetrahydrofuran.

[0069] In some embodiments, the solid filler can be mixed in an active solution at 20°C-30°C, and then impregnated and modified for 1-3 hours under physical mixing. After filtration to separate the solids, the solids are washed and dried to obtain the modified filler. In practice, physical mixing methods include mechanical stirring and ultrasonic treatment to improve the dispersibility and uniformity of the solid filler in the active solution.

[0070] In practice, when solid fillers include nanoparticles and chopped fibers, the nanoparticles and chopped fibers can be modified separately by impregnating them in an active solution, then separated and combined to obtain the modified filler. Specifically, when modifying nanoparticles and chopped fibers separately, the active solutions used in the two modifications are independent of each other. Alternatively, the nanoparticles and chopped fibers can be mixed beforehand and then added to the active solution for modification.

[0071] In some embodiments, 5 wt%-40 wt% of functional additives are also dispersed within the silicone rubber matrix. Specifically, the functional additives include crosslinking agents, catalysts, and inhibitors. In fact, inhibitors in the silicone rubber matrix can improve the stability of the composite silicone rubber material at low temperatures, while catalysts can promote the chain reaction between the crosslinking agent and rubber molecules in the silicone rubber matrix during addition vulcanization, and integrate the modified filler into the three-dimensional crosslinked network to form a co-crosslinked structure of the modified filler and the matrix.

[0072] In some embodiments, the crosslinking agent used includes a hydrogen-containing silicone oil crosslinking agent. Specifically, the preparation method of the hydrogen-containing silicone oil crosslinking agent includes: condensing and dehydrating an acid anhydride with an amino monomer to form an imide-siloxane oligomer, and then, under the action of an accelerator, reacting the imide-siloxane oligomer with a hydrogen-containing silicone monomer to generate the hydrogen-containing silicone oil crosslinking agent.

[0073] In some embodiments, the acid anhydride used in preparing the hydrogen-containing silicone oil crosslinking agent includes one of fluorenone dianhydride and triazine cyclic sulfide dianhydride. Specifically, the acid anhydride may consist of 20 mol%-80 mol% fluorenone dianhydride and the balance triazine cyclic sulfide dianhydride, or 20 mol%-80 mol% triazine cyclic sulfide dianhydride and the balance fluorenone dianhydride.

[0074] In some embodiments, the amino monomer used in preparing the hydrogen-containing silicone oil crosslinking agent includes one of 1,3-bis(3-aminopropyl)tetramethyldisiloxane and 4,6-dichloro-1,3,5-triazinecyclo-2-amine. Specifically, the amino monomer may consist of 20 mol%-80 mol% of 1,3-bis(3-aminopropyl)tetramethyldisiloxane and the balance of 4,6-dichloro-1,3,5-triazinecyclo-2-amine, or consist of 20 mol%-80 mol% of 4,6-dichloro-1,3,5-triazinecyclo-2-amine and the balance of 1,3-bis(3-aminopropyl)tetramethyldisiloxane.

[0075] In some embodiments, the accelerator used in preparing the hydrogen-containing silicone oil crosslinking agent includes one of a platinum catalyst, a caster catalyst, and a spanning catalyst, and the hydrogen-containing silicon monomer used includes one of methylhydrocyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyldihydrodisiloxane. Further, the molar ratio of the acid anhydride to the amino monomer used is (0.8-1.2):1, preferably with a slight excess of acid anhydride, for example, a molar ratio of acid anhydride to amino monomer of 1.01:1.

[0076] In some embodiments, the molar ratio of the hydrosilicone monomer to the imide-siloxane oligomer used in the chain extension reaction is 1:(2-4), and the molar ratio of the accelerator to the hydrosilicone monomer is (0.005-0.01):100. Further, the anhydride and amino monomer can be condensed at -4℃ to 4℃ to generate an imide-siloxane intermediate, which is then transferred to 150℃-250℃ for dehydration and cyclization. After adding the accelerator and hydrosilicone monomer, the chain extension reaction is carried out at 80℃-120℃ for 12h-24h.

[0077] In some embodiments, the catalysts used include cassette catalysts and platinum catalysts, and the inhibitors used include butynediol inhibitors. Further, the functional additives include 5 wt%-15 wt% of catalyst, 5 wt%-15 wt% of inhibitor, and the balance crosslinking agent (70 wt%-90 wt%).

[0078] See Figure 2 The present invention also provides a method for preparing a composite silicone rubber material, comprising the following steps: S1. Modified fillers are obtained by surface modification of solid fillers using triazine cyclofunctionalized silane coupling agents. S2. A composite silicone rubber material is prepared by dispersing the modified filler in a silicone rubber base.

[0079] In some embodiments, during step S2, modified fillers and functional additives can be dispersed within a silicone rubber base to obtain a composite silicone rubber material. Further, the silicone rubber base used includes one of vinyl silicone rubber, methyl vinyl silicone rubber, and methyl phenyl vinyl silicone rubber.

[0080] In fact, the present invention also provides a reinforced silicone rubber matrix obtained by addition vulcanization of the composite silicone rubber material in any of the above embodiments. Specifically, during the addition vulcanization process, the composite silicone rubber material can be pre-mixed to improve the dispersion uniformity of the modified filler and functional additives therein, and then placed at 80℃-120℃ for addition vulcanization to obtain the reinforced silicone rubber matrix.

[0081] This invention also provides a method for preparing fiber-reinforced silicone rubber, comprising: impregnating a fiber layer in a composite silicone rubber material and then separating it; and performing addition vulcanization at 80℃-120℃ to obtain fiber-reinforced silicone rubber. In practice, the composite silicone rubber material used is the composite silicone rubber material in any of the above embodiments.

[0082] In fact, by impregnating the fiber layer within the composite silicone rubber material, the composite silicone rubber material can penetrate deep into the fibers of the fiber layer. Therefore, after addition vulcanization, the fiber layer and modified filler can synergistically enhance the tensile strength and aging resistance of the silicone rubber. Furthermore, the fibers used in the fiber cloth include one of the following: high-modulus quartz fiber, carbon fiber, boron fiber, polyimide, and aramid.

[0083] Preparation Example 1 Example 1 of this preparation provides a method for preparing a triazine cyclofunctionalized silane coupling agent, comprising: mixing cyanuric chloride (CAS No.: 108-77-0) and KH550 (purchased from Jiangsu Lande New Material Technology Co., Ltd.) at a mass ratio of 11:9 and adding them into dimethylacetamide to obtain a mixed solution; adjusting the concentration of reactants in the mixed solution to 10%; adjusting the pH of the mixture to 6.0, stirring and reacting in an ice bath environment at 0°C for 2 hours, and then rotary distilling to obtain the triazine cyclofunctionalized silane coupling agent.

[0084] Preparation Example 2 Preparation Example 2 provides a method for preparing a triazine cyclofunctionalized silane coupling agent. The difference from Preparation Example 1 is that cyanuric chloride and KH792 (purchased from Jiangsu Lande New Material Technology Co., Ltd.) are added to dimethylacetamide at a mass ratio of 1:1 to prepare a mixed solution.

[0085] Preparation Example 3 Preparation Example 3 provides a method for preparing a triazine cyclofunctionalized silane coupling agent. The difference from Preparation Example 1 is that cyanuric chloride and KH550 (purchased from Jiangsu Lande New Material Technology Co., Ltd.) are mixed in a mass ratio of 1:1 and added to dimethylacetamide to obtain a mixed solution.

[0086] Preparation Example 4 Example 4 of this preparation provides a method for preparing a hydrogen-containing silicone oil crosslinking agent, comprising: mixing anhydride (fluorenone dianhydride and triazine cyclothioether dianhydride in a molar ratio of 2:3) and amino monomer (1,3-bis(3-aminopropyl)tetramethyldisiloxane and 4,6-dichloro-1,3,5-triazinecyclo-2-amine in a molar ratio of 1:1) at a molar ratio of 1.01:1, stirring and reacting in an ice bath at 0°C for 2 hours, then transferring to 200°C for dehydration and cyclization reaction for 3 hours to generate an imide-siloxane oligomer, adding a caster catalyst and methylhydrocyclotetrasiloxane (the molar ratio of methylhydrocyclotetrasiloxane to the imide-siloxane oligomer is 1:3) in a molar ratio of 0.005:100 and performing a chain extension reaction for 12 hours to obtain the hydrogen-containing silicone oil crosslinking agent. Example

[0087] This embodiment 1 provides a method for preparing a composite silicone rubber material, including the following steps: S1. Fumed silica (average particle size of 20 nm) and nanocrystalline cellulose (diameter of 95 nm and aspect ratio of 10) were impregnated in ethyl acetate solution of 5 wt% triazine cyclofunctionalized silane coupling agent (Preparation Example 1) at a solid-liquid ratio of 0.025 g / mL. After stirring and reacting at 25 °C for 2 h, the solids were separated, washed with deionized water and vacuum dried to obtain modified particles and modified fibers respectively. The modified particles and modified fibers were mixed at a mass ratio of 2:1 to obtain modified filler. S2. By mass, 20 parts of modified filler, 8 parts of hydrogen-containing silicone oil crosslinking agent (Preparation Example 4), 1 part of caster catalyst (purchased from Dongguan Ziaokai New Materials Co., Ltd.), and 1 part of butynol inhibitor were added to 100 parts of methyl vinyl silicone rubber (purchased from Shenzhen Feike Technology Co., Ltd., brand name 110 methyl vinyl silicone rubber) to obtain a composite silicone rubber material. Example

[0088] Example 2 provides a method for preparing a composite silicone rubber material. The difference from Example 1 is that in step S1, fumed silica (average particle size of 20 nm) and silicon nitride nanocrystals (diameter of 60 nm and aspect ratio of 50) are impregnated and modified, and the modified particles and modified fibers are mixed at a mass ratio of 1:1 to obtain a modified filler. In step S2, 25 parts of the modified filler, 8 parts of hydrogen-containing silicone oil crosslinking agent (preparation example 4), 1 part of caster catalyst, and 1 part of butynol inhibitor are added to 100 parts of methyl vinyl silicone rubber and mixed to obtain a composite silicone rubber material. Example

[0089] Example 3 provides a method for preparing a composite silicone rubber material. The difference from Example 1 is that in step S1, nano-calcium carbonate (average particle size of 100 nm) and silicon oxynitride nanocrystals (diameter of 60 nm and aspect ratio of 50) are mixed at a mass ratio of 1:1. The mixture is then stirred at 25°C for 2 hours in an ethyl acetate solution of 5 wt% triazine cyclofunctionalized silane coupling agent (preparation example 2) at a solid-liquid ratio of 0.025 g / mL. The solids are then separated, washed with deionized water, and vacuum dried to obtain the modified filler. Example

[0090] Example 4 provides a method for preparing a composite silicone rubber material. The difference from Example 1 is that in step S1, nano-calcium carbonate (average particle size of 100 nm) and nanocrystalline cellulose (diameter of 95 nm and aspect ratio of 10) are impregnated in an ethyl acetate solution of 5 wt% triazine cyclofunctionalized silane coupling agent (preparation example 3) at a solid-liquid ratio of 0.025 g / mL. After stirring and reacting at 25°C for 2 h, the solids are separated, washed with deionized water and vacuum dried to obtain modified particles and modified fibers, respectively. The modified particles and modified fibers are mixed at a mass ratio of 1:1 to obtain a modified filler.

[0091] Comparative Example 1 Comparative Example 1 provides a method for preparing a composite silicone rubber material. The difference from Example 1 is that in step S1, fumed silica (average particle size of 20 nm) and nanocrystalline cellulose (diameter of 95 nm and aspect ratio of 10) are impregnated in a 5 wt% KH550 ethyl acetate solution at a solid-liquid ratio of 0.025 g / mL. After stirring and reacting at 25°C for 2 h, the solids are separated, washed with deionized water, and vacuum dried to obtain modified particles and modified fibers, respectively. The modified particles and modified fibers are mixed at a mass ratio of 2:1 to obtain a modified filler.

[0092] Comparative Example 2 Comparative Example 2 provides a method for preparing a composite silicone rubber material. The difference from Example 1 is that the hydrogen-containing silicone oil in step S2 is polymethylhydrosiloxane (PMHS, purchased from Fangxin Biotechnology Co., Ltd., brand name PB13351).

[0093] Comparative Example 3 Comparative Example 3 provides a method for preparing a composite silicone rubber material. The difference from Comparative Example 1 is that the hydrogen-containing silicone oil in step S2 is polymethylhydrosiloxane (PMHS, purchased from Fangxin Biotechnology Co., Ltd., brand name PB13351).

[0094] Performance testing The composite silicone rubber materials obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were respectively mixed in a mixer, shaped, and vulcanized at 100°C to obtain reinforced silicone rubber gaskets. The mechanical properties (tensile strength, elongation at break) of the above-mentioned reinforced silicone rubber gaskets were tested using the methods described in GB / T 528-2009 and GB / T9127-2010, and the results are shown in Table 1 below.

[0095] Table 1 Mechanical property data of reinforced silicone rubber gaskets

[0096] Example 5 Example 5 provides a method for preparing fiber-reinforced silicone rubber, comprising: preparing polyimide nonwoven fiber cloth (three layers, density 120 g / cm³). 3 After impregnating a fiber cloth (0.8 mm thick) in a composite silicone rubber material (Example 1) for 8 hours, the fiber cloth adsorbed with the composite silicone rubber material was separated and vulcanized at 80°C to obtain fiber-reinforced silicone rubber. Example

[0097] This embodiment 6 provides a method for preparing fiber-reinforced silicone rubber, which differs from embodiment 5 in that it uses woven carbon fiber cloth (three layers, density 120 g / cm³). 3 (0.8 mm thick) was impregnated in a composite silicone rubber material (Example 2). Example

[0098] Example 7 provides a method for preparing fiber-reinforced silicone rubber, which differs from Example 5 in that it uses a three-layer polyimide nonwoven fabric (density 120 g / cm³). 3 (0.8 mm thick) was impregnated in a composite silicone rubber material (Example 3). Example

[0099] Example 8 provides a method for preparing fiber-reinforced silicone rubber, which differs from Example 5 in that it uses woven carbon fiber cloth (three layers, density 120 g / cm³). 3 (0.8 mm thick) was impregnated in a composite silicone rubber material (Example 4).

[0100] Performance testing The mechanical properties of the fiber-reinforced silicone rubbers in Examples 5 to 8 were tested using the methods described in GB / T 528-2009 and GB / T 9127-2010, and the results are shown in Table 2 below.

[0101] Table 2 Mechanical property data of fiber-reinforced silicone rubber

[0102] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A composite silicone rubber material, characterized in that, The composite silicone rubber material includes a silicone rubber base and a modified filler dispersed within the silicone rubber base. The modified filler is prepared by surface modification of a solid filler with a triazine cyclofunctionalized silane coupling agent. Preferably, the composite silicone rubber material includes 10wt%-30wt% of the modified filler.

2. The composite silicone rubber material according to claim 1, characterized in that: The solid filler comprises nanoparticles and chopped fibers; Preferably, the nanoparticles include one of fumed silica, precipitated silica, nano-alumina, and nano-calcium carbonate; Preferably, the chopped fibers include one of cellulose nanocrystals, silicon nitride nanocrystals, silicon carbide nanocrystals, and silicon oxynitride nanocrystals; Preferably, the average particle size of the nanoparticles is less than or equal to 200 nm; Preferably, the diameter of the chopped fibers is less than or equal to 500 nm; Preferably, the aspect ratio of the chopped fibers is greater than or equal to 20 and less than or equal to 100; Preferably, the solid filler comprises nanoparticles and short-cut fibers in a mass ratio of (1-2):(0.01-1); And / or, the silicone rubber base includes one of vinyl silicone rubber, methyl vinyl silicone rubber, and methyl phenyl vinyl silicone rubber.

3. The composite silicone rubber material according to claim 1, characterized in that, The preparation method of the triazine cyclofunctionalized silane coupling agent includes: In a liquid environment with pH=5-6 and 0℃-5℃, triazine ring compounds were reacted with silane coupling agents to obtain triazine ring functionalized silane coupling agents. Preferably, the triazine ring compound includes one of cyanuric chloride, cyanuric fluorochlorotri ... Preferably, the silane coupling agent includes one of KH550, KH792, and KH892; Preferably, the liquid environment includes one of acetonitrile, acetone, and chloroform; Preferably, the concentration of the reactant in the liquid environment is 5%-30%, and the reactant is composed of a triazine ring compound and a silane coupling agent; Preferably, the mass fraction of the triazine ring compound in the reactants is 35%-75%; Preferably, the mass fraction of the silane coupling agent in the reactants is 25%-65%; Preferably, the triazine ring compound is separated after reacting with the silane coupling agent for 1-3 hours; Preferably, the liquid environment is removed after the reaction to obtain a triazine cyclofunctionalized silane coupling agent; more preferably, the method for removing the liquid environment includes rotary distillation.

4. The composite silicone rubber material according to claim 1, characterized in that, When preparing modified fillers by surface modification of solid fillers using triazine cyclofunctionalized silane coupling agents, the process includes: The modified filler is obtained by wetting and modifying the solid filler in an active solution and then separating it; wherein the active solute in the active solution includes at least a triazine cyclofunctionalized silane coupling agent. Preferably, the solid filler in the active solution has a solid-liquid ratio of 0.02 g / mL to 0.05 g / mL; Preferably, the mass concentration of the triazine cyclofunctionalized silane coupling agent in the active solution is 2%-10%; Preferably, the solvent in the active solution includes one of ethyl acetate, ethanol, isopropanol, and tetrahydrofuran; Preferably, the solid filler is impregnated and modified in an active solution for 1-3 hours; Preferably, the modification is carried out by impregnation at 20℃-30℃; Preferably, the solid filler is modified by impregnation in an active solution under physical mixing, wherein the physical mixing includes stirring and ultrasonication; Preferably, when the solid filler comprises nanoparticles and chopped fibers, the impregnation modification includes: The modified filler was obtained by mixing nanoparticles with chopped fibers, impregnating and modifying them in an active solution, and then separating them. Alternatively, the nanoparticles and chopped fibers can be impregnated and modified separately in an active solution, then separated and combined to obtain the modified filler.

5. The composite silicone rubber material according to any one of claims 1 to 4, characterized in that, The silicone rubber base also contains dispersed functional additives; preferably, the composite silicone rubber material includes 5wt%-40wt% of the functional additives. Preferably, the functional additives include crosslinking agents, catalysts, and inhibitors; More preferably, the crosslinking agent includes a hydrogen-containing silicone oil crosslinking agent; More preferably, the catalyst includes a cassiterite catalyst or a platinum catalyst; More preferably, the inhibitor includes a butynol inhibitor; More preferably, the functional additive includes 5wt%-15wt% of a catalyst; More preferably, the functional adjuvant includes 5wt%-15wt% of an inhibitor; More preferably, the functional additive includes 70wt%-90wt% of a crosslinking agent.

6. The composite silicone rubber material according to claim 5, characterized in that, The preparation method of the hydrogen-containing silicone oil crosslinking agent includes: After the acid anhydride and amino monomer are condensed and dehydrated to form a ring, an imide-siloxane oligomer is generated. Then, under the action of an accelerator, the imide-siloxane oligomer undergoes a chain extension reaction with a hydrogen-containing silicon monomer to generate a hydrogen-containing silicone oil crosslinking agent. Preferably, the acid anhydride includes one of fluorenone dianhydride and triazine cyclothioether dianhydride; More preferably, the anhydride comprises 20 mol%-80 mol% fluorenone dianhydride; More preferably, the acid anhydride comprises 20 mol%-80 mol% of triazine cyclothioether dianhydride; Preferably, the amino monomer comprises one of 1,3-bis(3-aminopropyl)tetramethyldisiloxane and 4,6-dichloro-1,3,5-triazinecyclo-2-amine; More preferably, the amino monomer comprises 20 mol%-80 mol% of 1,3-bis(3-aminopropyl)tetramethyldisiloxane; More preferably, the amino monomer comprises 20 mol%-80 mol% of 4,6-dichloro-1,3,5-triazine-2-amine; Preferably, the promoter includes one of a platinum catalyst, a caster catalyst, and a spanning catalyst; Preferably, the hydrogen-containing silicon monomer comprises one of methylhydrocyclotetrasiloxane, octamethylcyclotetrasiloxane, and tetramethyldihydrodisiloxane; Preferably, the molar ratio of the acid anhydride to the amino monomer is (0.8-1.2):1; Preferably, the molar ratio of the hydrogen-containing silicon monomer to the imide-siloxane oligomer is 1:(2-4); Preferably, the molar ratio of the accelerator to the hydrogen-containing silicon monomer is (0.005-0.01):100; Preferably, the acid anhydride and the amino monomer are subjected to a condensation reaction at -4°C to 4°C to generate an imide-siloxane intermediate; Preferably, the acid anhydride and amino monomer are condensed and then dehydrated to form a ring at 150℃-250℃. Preferably, the chain extension reaction is carried out at 80℃-120℃; Preferably, the chain extension reaction lasts for 12-24 hours.

7. A method for preparing a composite silicone rubber material as described in any one of claims 1 to 6, characterized in that, include: Modified fillers are obtained by surface modification of solid fillers using triazine cyclofunctionalized silane coupling agents; A composite silicone rubber material is prepared by dispersing modified fillers in a silicone rubber base; preferably, a composite silicone rubber material is prepared by dispersing modified fillers and functional additives in a silicone rubber base.

8. A reinforced silicone rubber matrix obtained by addition vulcanization of a composite silicone rubber material as described in any one of claims 1 to 6 or a composite silicone rubber material prepared by the preparation method as described in claim 7.

9. A method for preparing fiber-reinforced silicone rubber, characterized in that, include: The fiber layer is separated after being impregnated in a composite silicone rubber material; Addition vulcanization at 80℃-120℃ yields fiber-reinforced silicone rubber; The composite silicone rubber material is the composite silicone rubber material according to any one of claims 1 to 6; Preferably, the fibers in the fiber layer include one of high-modulus quartz fiber, carbon fiber, boron fiber, polyimide, and aramid.

10. A fiber-reinforced silicone rubber prepared by the method described in claim 9.

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