A ceramic silicone rubber composite belt and its preparation method

Abstract

The present invention discloses a ceramic silicone rubber composite tape and a method for preparing the same, comprising a ceramic silicone rubber composite material and spray-coated glass cloth. The ceramic silicone rubber composite material is prepared from the following ingredients: silicone rubber, a silicone oil-containing agent, nano-silicon dioxide, a ceramic powder, a composite vulcanizer, a modified cross-linking agent, and additives. Compared to the prior art, the ceramic silicone rubber composite tape prepared by the present invention utilizes nano-silicon dioxide and mica powder to enhance the hardness, wear resistance, and strength of fluorosilicone rubber. Simultaneously, the addition of methyl vinyl silicone oil, a modified cross-linking agent, and boron oxide increases the cross-linking density and flexural strength of the composite material, thereby raising its initial decomposition temperature and making it more heat-resistant. The composite tape can be widely used in sealing, heat insulation, and protection applications under harsh working conditions such as high temperature, high pressure, and high speed.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic silicone rubber composite belts, and in particular to a ceramic silicone rubber composite belt and a preparation method thereof. Background Art

[0002] Ceramic silicone rubber composite tape is a composite material composed of silicone rubber and ceramic powders. It meets the mechanical property requirements of both the rubber and ceramic bodies: excellent rubber properties at room temperature, while high mechanical properties and a dense ceramic body are formed at high temperatures. It is widely used in sealing, thermal insulation, and protective applications under harsh operating conditions such as high temperature, high pressure, and high speed. Several related technologies exist, such as carbon fiber-reinforced ceramic silicone rubber composites, which can enhance their strength and stiffness. Using different types and shapes of ceramic powders, such as silicon carbide, aluminum oxide, and zirconium oxide, can adjust the composite's properties. Using different types and proportions of silicone rubber, such as fluorosilicone rubber and nitrile butadiene rubber, can modify the composite's hardness, elastic modulus, and heat resistance. Using different types and proportions of fillers, such as nanopowders, graphite, and carbon fibers, can enhance the composite's strength, thermal conductivity, and electrical conductivity.

[0003] However, ceramics with excellent mechanical properties often require large amounts of inorganic fillers, which conflict with the mechanical properties of rubber. Raw materials such as ceramic powder and silicone rubber are expensive, and a large number of additives and modifiers are required during the preparation process, increasing the preparation cost. Due to the strong viscosity of silicone rubber, composite materials are prone to adhesion problems during the preparation process, resulting in uneven preparation or unstable product quality. In short, the preparation technology of ceramic silicone rubber composite tapes is very diverse, and it is necessary to select appropriate materials and preparation methods according to specific application requirements to achieve optimal performance.

[0004] Authorized invention patent CN113402993B discloses a ceramic silicone rubber composite tape with a mica layer and a method for preparing the same. The composite tape has a three-layer structure and is prepared by the following steps: first, preparing a ceramic silicone rubber sheet, then preparing a self-adhesive silicone rubber sheet, and finally cold-pressing the surface-treated mica tape, the ceramic silicone rubber sheet, and the self-adhesive silicone rubber sheet, and irradiating and cross-linking the three layers to prepare a ceramic silicone rubber composite tape with a mica layer in the middle. This invention produces a composite tape with a three-layer structure that has excellent high-temperature resistance, flame retardancy, mechanical strength, and bonding properties. It can be widely used in the wire and cable industry, greatly improving the safety of cable use. However, the ceramic silicone rubber composite tape prepared by this invention has the disadvantages of low cross-linking density and bending strength, and poor high-temperature resistance. Summary of the Invention

[0005] In view of the shortcomings of ceramic silicone rubber composite tape in the prior art, such as low cross-linking density and bending strength, and poor high temperature resistance, the technical problem to be solved by the present invention is to provide a ceramic silicone rubber composite tape with high cross-linking density and bending strength, good high temperature resistance, and a preparation method thereof.

[0006] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0007] A ceramic silicone rubber composite belt comprises a ceramic silicone rubber composite material and a sprayed glass cloth.

[0008] The ceramic silicone rubber composite material is prepared from the following ingredients: silicone rubber, silicone oil-containing agent, nano-silicon dioxide, ceramic powder, composite vulcanizing agent, modified cross-linking agent, and auxiliary agent.

[0009] Preferably, the ceramic silicone rubber composite material is prepared from the following ingredients in parts by weight: 60-100 parts of silicone rubber, 1-5 parts of silicone oil-containing agent, 10-30 parts of nano-silicon dioxide, 80-100 parts of ceramic powder, 1-3 parts of composite vulcanizing agent, 0.1-1 part of modified cross-linking agent, and 10-15 parts of auxiliary agent.

[0010] The silicone rubber is at least one of dimethyl silicone rubber, methylphenylvinyl silicone rubber and fluorosilicone rubber.

[0011] The porcelain powder is at least one of mica powder, glass powder or wollastonite.

[0012] The silicone oil-containing agent is at least one of methyl vinyl silicone oil and phenyl methyl silicone oil.

[0013] The auxiliary agent is at least one of low-melting-point glass powder, zinc borate, boron oxide, aluminum oxide, and magnesium oxide.

[0014] The preparation method of the modified cross-linking agent is as follows, in parts by weight:

[0015] S1. Under a nitrogen atmosphere, 5 to 15 parts of levorotatory beta-pinene, 15 to 20 parts of N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, and 0.1 to 0.3 parts of platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane are mixed, followed by stirring at 90 to 100° C. and 100 to 500 rpm for 4 to 8 hours, and distilling at 110 to 130° C. and 0.01 to 0.05 MPa for 1 to 3 hours to obtain a pretreated product;

[0016] S2. Add 3 to 5 parts of the pretreated product to 50 to 70 parts of lauryl polymethylsiloxane, stir at a speed of 1000 to 3000 rpm for 10 to 30 minutes, then add 0.2 to 0.6 parts of dibutyltin diacetate, stir at a speed of 300 to 600 rpm for 20 to 40 minutes, and centrifuge at 1000 to 5000 rpm to remove bubbles for 1 to 6 minutes to obtain a modified crosslinking agent.

[0017] The preparation method of the ceramic silicone rubber composite belt is as follows:

[0018] Step 1, weighing each raw material according to weight, adding silicone rubber, nano-silica, porcelain powder, silicone oil agent, modified crosslinking agent, and additives into an internal mixer, stirring and mixing at 80-110° C. and 50-70 rpm for 20-40 minutes, then placing on an open mixer and adding a composite vulcanizing agent, mixing at 80-100 rpm and 60-70° C. for 5-12 minutes, and thinning out to obtain a mixed rubber;

[0019] Step 2, vulcanizing the rubber mixture on a flat vulcanizer for 30 to 40 minutes at a vulcanization temperature of 155 to 175° C. and a vulcanization pressure of 5 to 10 MPa to obtain a ceramic silicone rubber composite material;

[0020] Step 3: Spraying the silicone-acrylic emulsion onto the glass cloth, drying it at a temperature of 60-90°C, and spraying it with a thickness of 0.1-0.5 mm to obtain a sprayed glass cloth; calendering and compounding the ceramic silicone rubber composite material prepared in step 2 and the sprayed glass cloth, and then baking and vulcanizing them at 100-130°C for 10-30 minutes to obtain a ceramic silicone rubber composite tape.

[0021] The composite vulcanizing agent is a mixture of bisphenol AF and benzyltriphenylphosphonium chloride (BPP), and the mass ratio of the two is 1 to 5:1.

[0022] The present invention adds fluorosilicone rubber, nano-silicon dioxide, mica powder, methyl vinyl silicone oil, a modified crosslinking agent, and boron oxide into an internal mixer, stirs and mixes at high temperature, adds a composite vulcanizing agent, mixes, and thins out a sheet to obtain a rubber mix; the rubber mix is vulcanized to obtain a ceramic silicone rubber composite material; glass cloth treated with silicone acrylic emulsion is baked and dried, the ceramic silicone rubber composite material and the glass cloth treated with silicone acrylic emulsion are rolled and composited, baked and vulcanized to obtain a ceramic silicone rubber composite tape. The modified crosslinking agent is prepared by mixing levo-beta-pinene, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, and platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane under a nitrogen atmosphere, stirring at high temperature, and distilling under reduced pressure to obtain a pre-treated product; the pre-treated product is added to lauryl polymethylsiloxane and stirred, and then dibutyltin diacetate is added and stirred, and centrifuged to remove bubbles to obtain the modified crosslinking agent.

[0023] The mechanical properties of ceramics are largely dependent on their density. The density of a ceramic can be a macroscopic reflection of the quality of the fired ceramic. Higher density generally indicates better density, while lower density indicates poor density and the potential for more internal pores, which can affect flexural strength. L-beta-pinene reacts with N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid. L-beta-pinene has a terpene ring structure and no polar groups. Therefore, the grafted L-beta-pinene exhibits good compatibility with fluorosilicone rubber, increasing the crosslink density. The strong, rigid structure of L-beta-pinene enhances chain entanglement. Furthermore, the flexural strength of ceramicized silicone rubber composite tapes increases initially and then decreases with increasing modified crosslinker content. At low crosslinker concentrations, the crosslinker is evenly dispersed throughout the matrix. Increasing the modified crosslinker content improves the mechanical properties of ceramicized silicone rubber composite tapes. However, when the amount of modified crosslinker exceeds a certain level, the flexural strength of the ceramic silicone rubber composite tape begins to decrease. This is likely due to aggregation and self-crosslinking reactions caused by the excessive amount of modified crosslinker. L-beta-pinene, with its rigid structure, is incorporated into fluorosilicone rubber, causing molecular chain entanglement. This inhibits the movement of fluorosilicone rubber molecular chains and the rearrangement of polysiloxane, effectively preventing the decomposition of polysiloxane fragments into cyclic oligomers, thereby improving the density, thermal stability, and flexural strength of the ceramic silicone rubber composite tape.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1) The ceramicized silicone rubber composite tape prepared by the present invention utilizes nano-silicon dioxide and mica powder to enhance the hardness, wear resistance, and strength of the fluorosilicone rubber. The addition of methyl vinyl silicone oil, a modified crosslinking agent, and boron oxide enhances the composite's adhesion and density, improving its high-temperature resistance. Furthermore, the use of a composite vulcanizing agent composed of bisphenol AF and benzyltriphenylphosphonium chloride achieves rapid vulcanization and excellent heat resistance.

[0026] 2) The present invention utilizes substances such as levorotatory-beta-pinene and N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid to successfully prepare a modified crosslinking agent with good performance. At the same time, the addition of platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane catalyst can promote the crosslinking reaction, increase the crosslinking density and flexural strength of the composite material, thereby increasing its initial decomposition temperature and making it more resistant to high temperatures.

[0027] 3) The ceramic silicone rubber composite belt prepared by the present invention not only has excellent high temperature resistance and mechanical properties, but also has a simple preparation method and low cost, and has broad application prospects.

[0028] 4) The ceramic silicone rubber composite tape prepared by the present invention has excellent mechanical properties and thermal stability, and can be widely used in the fields of sealing, heat insulation, protection, etc. under harsh working conditions such as high temperature, high pressure, and high speed. DETAILED DESCRIPTION

[0029] Main sources of substances:

[0030] Fluorosilicone rubber: Model: KX-803, Guangzhou Kanglunxi Chemical Technology Co., Ltd.

[0031] Nano-silica: Product No.: HL150, Hubei Huifu Nanomaterials Co., Ltd.

[0032] Methyl vinyl silicone oil: Jinan Xinglongda Chemical Co., Ltd., brand: 5846.

[0033] Mica powder: particle size: 1200 mesh.

[0034] L-beta-pinene: CAS number: 18172-67-3, Hubei Zhenbo Chemical Co., Ltd.

[0035] β-Pinene: Shanghai Aladdin Biochemical Technology Co., Ltd., CAS No.: 18172-67-3.

[0036] Silicone acrylic emulsion: Product No.: 01, Viscosity: 2200(S), Henan Yuansheng New Material Technology Co., Ltd.

[0037] Glass cloth: Item No.: XT003, Grade: A, Zhejiang Xuantai New Materials Co., Ltd.

[0038] Example 1

[0039] A method for preparing a ceramic silicone rubber composite belt is as follows:

[0040] Step 1, 80kg of fluorosilicone rubber, 20kg of nano-silica, 90kg of mica powder, 3kg of methyl vinyl silicone oil, 0.6kg of modified crosslinking agent, and 12kg of boron oxide were added to an internal mixer, stirred and mixed at 100°C and 60rpm for 30min, then placed on an open mill and 2kg of composite vulcanizing agent was added, mixed at 90rpm and 65°C for 10min, and thinned to obtain a rubber mixture;

[0041] Step 2, vulcanizing the rubber mixture on a flat vulcanizer for 35 minutes at a vulcanization temperature of 165° C. and a vulcanization pressure of 8 MPa to obtain a ceramic silicone rubber composite material;

[0042] Step 3: Spray the silicone-acrylic emulsion onto the glass cloth, dry it at 80°C, and spray it to a thickness of 0.2 mm to obtain a sprayed glass cloth; calender and composite the ceramic silicone rubber composite material prepared in step 2 with the sprayed glass cloth, and then bake and vulcanize it at 120°C for 15 minutes to obtain a ceramic silicone rubber composite tape.

[0043] The composite vulcanizing agent is a mixture of bisphenol AF and benzyltriphenylphosphonium chloride (BPP), with a mass ratio of the two being 3:1.

[0044] The preparation method of the modified cross-linking agent is as follows:

[0045] S1. Under a nitrogen atmosphere, 10 g of levorotatory-beta-pinene, 18 g of N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, and 0.2 g of platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane were mixed, followed by stirring at 95° C. and 300 rpm for 6 h, and distillation at 125° C. and 0.03 MPa for 2 h to obtain a pretreated product;

[0046] S2. Add 4 g of the pretreated product to 60 g of lauryl polymethylsiloxane, stir at 2000 rpm for 20 min, then add 0.4 g of dibutyltin diacetate, stir at 500 rpm for 30 min, and centrifuge at 3000 rpm to remove bubbles for 5 min to obtain a modified crosslinking agent.

[0047] Example 2

[0048] A method for preparing a ceramic silicone rubber composite belt is as follows:

[0049] Step 1, 80kg of fluorosilicone rubber, 20kg of nano-silica, 90kg of mica powder, 3kg of methyl vinyl silicone oil, 0.4kg of modified crosslinking agent, and 12kg of boron oxide were added to an internal mixer, stirred and mixed at 100°C and 60rpm for 30min, then placed on an open mixer and 2kg of composite vulcanizing agent was added, mixed at 90rpm and 65°C for 10min, and thinned to obtain a rubber mixture;

[0050] Step 2, vulcanizing the rubber mixture on a flat vulcanizer for 35 minutes at a vulcanization temperature of 165° C. and a vulcanization pressure of 8 MPa to obtain a ceramic silicone rubber composite material;

[0051] Step 3: Spray the silicone-acrylic emulsion onto the glass cloth, dry it at 80°C, and spray it to a thickness of 0.2 mm to obtain a sprayed glass cloth; calender and composite the ceramic silicone rubber composite material prepared in step 2 with the sprayed glass cloth, and then bake and vulcanize it at 120°C for 15 minutes to obtain a ceramic silicone rubber composite tape.

[0052] The preparation method of the composite vulcanizing agent is the same as that in Example 1.

[0053] The preparation method of the modified cross-linking agent is the same as that in Example 1.

[0054] Example 3

[0055] A method for preparing a ceramic silicone rubber composite belt is as follows:

[0056] Step 1, 80kg of fluorosilicone rubber, 20kg of nano-silica, 90kg of mica powder, 3kg of methyl vinyl silicone oil, 0.8kg of modified crosslinking agent, and 12kg of boron oxide were added to an internal mixer, stirred and mixed at 100°C and 60rpm for 30min, then placed on an open mill and 2kg of composite vulcanizing agent was added, mixed at 90rpm and 65°C for 10min, and thinned to obtain a rubber mixture;

[0057] Step 2, vulcanizing the rubber mixture on a flat vulcanizer for 35 minutes at a vulcanization temperature of 165° C. and a vulcanization pressure of 8 MPa to obtain a ceramic silicone rubber composite material;

[0058] Step 3: Spray the silicone-acrylic emulsion onto the glass cloth, dry it at 80°C, and spray it to a thickness of 0.2 mm to obtain a sprayed glass cloth; calender and composite the ceramic silicone rubber composite material prepared in step 2 with the sprayed glass cloth, and then bake and vulcanize it at 120°C for 15 minutes to obtain a ceramic silicone rubber composite tape.

[0059] Example 4

[0060] The preparation method of a ceramic silicone rubber composite belt is basically the same as that of Example 1, with the only difference being that the preparation method of the modified cross-linking agent is different.

[0061] The preparation method of the modified cross-linking agent is as follows:

[0062] S1. Under a nitrogen atmosphere, 10 g of β-pinene, 18 g of N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, and 0.2 g of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane were mixed, followed by stirring at 95° C. and 300 rpm for 6 h, and distillation at 125° C. and 0.03 MPa for 2 h to obtain a pretreated product;

[0063] S2. Add 4 g of the pretreated product to 60 g of lauryl polymethylsiloxane, stir at 2000 rpm for 20 min, then add 0.4 g of dibutyltin diacetate, stir at 500 rpm for 30 min, and centrifuge at 3000 rpm to remove bubbles for 5 min to obtain a modified crosslinking agent.

[0064] The preparation method of the composite vulcanizing agent is the same as that in Example 1.

[0065] Example 5

[0066] The preparation method of a ceramic silicone rubber composite belt is basically the same as that of Example 1, with the only difference being that the preparation method of the modified cross-linking agent is different.

[0067] The preparation method of the modified cross-linking agent is as follows:

[0068] S1. Under a nitrogen atmosphere, 10 g of levorotatory beta-pinene, 18 g of tris(hydroxymethyl)methylaminoethanesulfonic acid, and 0.2 g of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane were mixed, followed by stirring at 95° C. and 300 rpm for 6 h, and distillation at 125° C. and 0.03 MPa for 2 h to obtain a pretreated product;

[0069] S2. Add 4 g of the pretreated product to 60 g of lauryl polymethylsiloxane, stir at 2000 rpm for 20 min, then add 0.4 g of dibutyltin diacetate, stir at 500 rpm for 30 min, and centrifuge at 3000 rpm to remove bubbles for 5 min to obtain a modified crosslinking agent.

[0070] The preparation method of the composite vulcanizing agent is the same as that in Example 1.

[0071] Comparative Example 1

[0072] The preparation method of a ceramic silicone rubber composite belt is basically the same as that of Example 1, with the only difference being that the preparation method of the modified cross-linking agent is different.

[0073] The preparation method of the modified cross-linking agent is as follows:

[0074] S1. Under a nitrogen atmosphere, 10 g of β-pinene, 18 g of tris(hydroxymethyl)methylaminoethanesulfonic acid, and 0.2 g of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane were mixed, followed by stirring at 95° C. and 300 rpm for 6 h, and distillation at 125° C. and 0.03 MPa for 2 h to obtain a pretreated product;

[0075] S2. Add 4 g of the pretreated product to 60 g of lauryl polymethylsiloxane, stir at 2000 rpm for 20 min, then add 0.4 g of dibutyltin diacetate, stir at 500 rpm for 30 min, and centrifuge at 3000 rpm to remove bubbles for 5 min to obtain a modified crosslinking agent.

[0076] The preparation method of the composite vulcanizing agent is the same as that in Example 1.

[0077] Test Example 1

[0078] Bending strength test

[0079] The test standard is GB / T6569-2006, "Test Method for Flexural Strength of Fine Ceramics." A universal testing machine, model RGM-4100, manufactured by Shenzhen Ruige Instrument Co., Ltd., was used to conduct three-point flexural strength tests on ceramic products calcined at different temperatures at a test speed of 0.5 mm / min. Maximum load: 500 kN.

[0080] Each group was tested three times and the average value was taken. The test results are shown in Table 1.

[0081] Table 1: Bending strength test results

[0082] Trial plan Maximum bending fracture force F(N) Example 1 11.47 Example 2 9.61 Example 3 9.50 Example 4 10.3 Example 5 10.1 Comparative Example 1 9.27

[0083] Test Example 2

[0084] Density test

[0085] The density of ceramics is tested using the drainage method, which uses the water level change of the sample in the volumetric flask to test. The calculation formula is as follows:

[0086] ρ=(m2-m1) / V 样品

[0087] V 样品 =V 瓶 -[(m1-m0)+(m3-m2)] / ρ 液

[0088] Where ρ is the density of the ceramic body, g / cm 3 ;

[0089] V 样品 is the volume of the ceramic body being tested, cm 3 ;

[0090] m0 is the mass of the volumetric flask, g;

[0091] m1 is the mass of solution added to the scale line, g;

[0092] m2 is the mass of the sample after the solution is added, g;

[0093] m3 is the mass after the water level line and the scale line of the volumetric flask coincide with each other after adding the sample, g;

[0094] V 瓶 is the standard volume of the volumetric flask, mL;

[0095] ρ 液 To test the density of the liquid, g / cm 3 .

[0096] Each group was tested three times and the average value was taken. The test results are shown in Table 2.

[0097] Table 2: Density test results

[0098]

[0099]

[0100] Test Example 3

[0101] Thermal performance test

[0102] Using a German NETZSCH STA449C / 3 / G integrated thermal analyzer, differential scanning calorimetry-thermogravimetry (DSC-TG) was used to analyze the onset decomposition temperature of the ceramicized silicone rubber composite tape during heating from room temperature to 1200°C at a rate of 10°C / min in air. The test results are shown in Table 3.

[0103] Table 3: Thermal performance test results

[0104] Trial plan Initial decomposition temperature (℃) Example 1 452 Example 2 425 Example 3 417 Example 4 422 Example 5 424 Comparative Example 1 406

[0105] It can be seen from the test results of Test Examples 1 to 3 that Example 1 has the best bending strength, density and initial decomposition temperature. The possible reason is that in Example 1 of the present invention, fluorosilicone rubber, nano-silica, mica powder, methyl vinyl silicone oil, modified cross-linking agent and boron oxide are added to an internal mixer, stirred and mixed at high temperature, a composite vulcanizing agent is added, mixed, and thinned to obtain a rubber mix; the rubber mix is vulcanized to obtain a ceramic silicone rubber composite material; glass cloth is treated with silicone acrylic emulsion and dried, and the ceramic silicone rubber composite material and glass cloth treated with silicone acrylic emulsion are calendered and compounded, and the mixture is baked and vulcanized to obtain a ceramic silicone rubber composite tape. The modified cross-linking agent is prepared by mixing levorotatory-beta-pinene, N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid and platinum (0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane under a nitrogen atmosphere, stirring at high temperature, and distilling under reduced pressure to obtain a pre-treated product; the pre-treated product is added to lauryl polymethylsiloxane and stirred, and then dibutyltin diacetate is added and stirred, and the mixture is centrifuged to remove bubbles to obtain a modified cross-linking agent.

[0106] The mechanical properties of ceramics are largely dependent on their density. The density of a ceramic can be a macroscopic reflection of the quality of the fired ceramic. Higher density generally indicates better density, while lower density indicates poor density and the potential for more internal pores, which can affect flexural strength. L-beta-pinene reacts with N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid. L-beta-pinene has a terpene ring structure and no polar groups. Therefore, the grafted L-beta-pinene exhibits good compatibility with fluorosilicone rubber, increasing the crosslink density. The strong, rigid structure of L-beta-pinene enhances chain entanglement. Furthermore, the flexural strength of ceramicized silicone rubber composite tapes increases initially and then decreases with increasing modified crosslinker content. At low crosslinker concentrations, the crosslinker is evenly dispersed throughout the matrix. Increasing the modified crosslinker content improves the mechanical properties of ceramicized silicone rubber composite tapes. However, when the amount of modified crosslinker exceeds a certain level, the flexural strength of the ceramic silicone rubber composite tape begins to decrease. This is likely due to aggregation and self-crosslinking reactions caused by the excessive amount of modified crosslinker. L-beta-pinene, with its rigid structure, is incorporated into fluorosilicone rubber, causing molecular chain entanglement. This inhibits the movement of fluorosilicone rubber molecular chains and the rearrangement of polysiloxane, effectively preventing the decomposition of polysiloxane fragments into cyclic oligomers, thereby improving the density, thermal stability, and flexural strength of the ceramic silicone rubber composite tape.

Claims

1. A ceramic silicone rubber composite belt, characterized in that: Including ceramic silicone rubber composite materials and spray-coated glass cloth; The ceramic silicone rubber composite material is prepared from the following components in parts by weight: 60-100 parts of silicone rubber, 1-5 parts of silicone oil agent, 10-30 parts of nano-silicon dioxide, 80-100 parts of ceramic powder, 1-3 parts of composite vulcanizing agent, 0.1-1 parts of modified cross-linking agent, and 10-15 parts of auxiliary agent; The preparation method of the modified cross-linking agent is as follows, in parts by weight: S1. Under a nitrogen atmosphere, 5-15 parts of levorotatory-beta-pinene, 15-20 parts of N,N-bis(2-hydroxyethyl)-2-aminoethanesulfonic acid, and 0.1-0.3 parts of platinum(0)-1,3-diethylene-1,1,3,3-tetramethyldisiloxane are mixed, followed by stirring at 90-100° C. and 100-500 rpm for 4-8 hours, and distilling at 110-130° C. and 0.01-0.05 MPa for 1-3 hours to obtain a pretreated product; S2. Add 3-5 parts of the pretreated product to 50-70 parts of lauryl polymethylsiloxane, stir at a speed of 1000-3000 rpm for 10-30 min, then add 0.2-0.6 parts of dibutyltin diacetate, stir at a speed of 300-600 rpm for 20-40 min, and centrifuge at 1000-5000 rpm to remove bubbles for 1-6 min to obtain a modified crosslinking agent.

2. A ceramic silicone rubber composite belt according to claim 1, characterized in that: The silicone rubber is at least one of dimethyl silicone rubber, methylphenylvinyl silicone rubber and fluorosilicone rubber.

3. The ceramic silicone rubber composite belt according to claim 1, characterized in that: The porcelain powder is at least one of mica powder, glass powder or wollastonite.

4. The ceramic silicone rubber composite belt according to claim 1, characterized in that: The silicone oil-containing agent is at least one of methyl vinyl silicone oil and phenyl methyl silicone oil.

5. The ceramic silicone rubber composite belt according to claim 1, characterized in that: The auxiliary agent is at least one of low-melting-point glass powder, zinc borate, boron oxide, aluminum oxide, and magnesium oxide.

6. A method for preparing the ceramic silicone rubber composite tape according to any one of claims 1 to 5, characterized in that: The preparation method is as follows: Step 1, weighing each raw material according to weight, adding silicone rubber, nano-silica, porcelain powder, silicone oil agent, modified crosslinking agent, and additives into an internal mixer, stirring and mixing at 80-110° C. and 50-70 rpm for 20-40 minutes, then placing on an open mixer and adding a composite vulcanizing agent, mixing at 80-100 rpm and 60-70° C. for 5-12 minutes, and thinning out to obtain a mixed rubber; Step 2, vulcanizing the rubber mixture on a flat vulcanizer for 30-40 minutes at a vulcanization temperature of 155-175° C. and a vulcanization pressure of 5-10 MPa to obtain a ceramic silicone rubber composite material; Step 3: Spraying the silicone-acrylic emulsion onto the glass cloth, drying it at a temperature of 60-90°C, and spraying it with a thickness of 0.1-0.5 mm to obtain a sprayed glass cloth; calendering and compounding the ceramic silicone rubber composite material prepared in step 2 and the sprayed glass cloth, and then baking and vulcanizing them at 100-130°C for 10-30 minutes to obtain a ceramic silicone rubber composite tape.

7. The method according to claim 6, wherein The composite vulcanizing agent is a mixture of bisphenol AF and benzyl triphenyl phosphonium chloride, and the mass ratio of the two is 1-5:1.

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