High temperature release silicone tube and method of making same

Abstract

The application discloses a high-temperature anti-adhesion silica gel pipe and a manufacturing method thereof, and relates to the technical field of silica gel production. On one hand, the silica gel pipe comprises connecting sections at two ends for being connected with metal clamps. The pipe wall corresponding to the connecting sections comprises, from inside to outside, a high-temperature-resistant anti-adhesion fluorosilicone rubber strip, a silica gel base layer and a high-temperature-resistant aramid rubberized fabric. On the other hand, the manufacturing method comprises the following steps: winding a layer of high-temperature-resistant anti-adhesion fluorosilicone rubber strip on the connecting section of a tubular core film; integrally laying a silica gel base layer on the tubular core film, and the silica gel base layer is attached outside the high-temperature-resistant anti-adhesion fluorosilicone rubber strip; attaching a layer of aramid rubberized fabric outside the silica gel base layer at the connecting section; and cooling and extracting the tubular core film after vulcanization reaction. By attaching the high-temperature-resistant anti-adhesion fluorosilicone rubber strip and the high-temperature-resistant aramid rubberized fabric outside and inside the silica gel base layer respectively, the silica gel pipe and the metal clamps and metal pipe joints closely connected with the silica gel pipe do not adhere to each other after long-time work under high temperature.

Description

Technical Field

[0001] This invention relates to the field of silicone production technology, specifically to a high-temperature anti-adhesion silicone tube and its manufacturing method. Background Technology

[0002] Silicone tubing, due to its flexibility and ease of assembly and disassembly, is commonly used for pipe connections between various components in vehicles. Silicone tubing used in automobiles requires excellent resistance to high and low temperatures, corrosion, high pressure, and oil, especially in the intake and exhaust systems of automotive engines, and the intake and exhaust pipes of refrigerants. Currently, a type of silicone tubing used in automotive aftermarket manufacturing is produced by winding a silicone sheet and a reinforcing layer adhered to it to form a tubing structure, followed by vulcanization molding. This type of tubing possesses excellent resistance to high and low temperatures, high pressure, and corrosion.

[0003] Currently, during vehicle operation, the temperature of the silicone hoses used in the engine remains above 180℃. To prevent the silicone hoses from detaching, the usual procedure is to tighten the connection between the silicone hose and the engine using metal clamps, typically with a torque of around 5.5N. After a period of operation, when removing the metal clamps or metal fittings, the activity of silicone rubber molecules, residual vulcanizing agents, silane coupling agents, and metal oxides on the metal surface is greatly enhanced under continuous high temperatures. Through their interaction, the rubber layer and the metal surface not only form a physical mechanical interlock, but also generate strong chemical bonds between free radicals produced after the dehydrogenation of polydimethylsiloxane molecules, silane coupling agents, and metal surface active substances. When this bond strength exceeds the adhesive strength between the silicone rubber hose's rubber layer and the fiber reinforcement layer, removing the metal clamps or metal fittings causes the rubber layer to adhere to the tightly contacting metal component while peeling off from the fiber reinforcement layer, rendering the silicone hose unusable after disassembly.

[0004] Existing technology one provides a silicone material for automotive silicone hoses that does not adhere to metal under continuous high temperatures. This silicone material, by weight, comprises: 100-120 parts silicone rubber, 6-8 parts structure control agent, 6-11 parts silane coupling agent, 2-5 parts silicone oil, 1-2 parts bis(2,5-dimethyl)propane, and 38-60 parts silica. However, this silicone hose's high-temperature operating condition is only 200°C, which cannot meet the technical requirement of 250°C for long-term use of intercooler intake silicone hoses in commercial vehicles, and its cost is relatively high. Existing technology two provides a turbocharger intake pipe, including a pipe body. The connection between the pipe body and the turbocharger intake pipe is formed with an insulating part made of a high-temperature resistant material inside the connection, isolating the connection and the intake pipe. Its inventive feature is that by setting an insulating part made of a high-temperature resistant material inside the connection, the connection and the turbocharger intake pipe can be effectively isolated, reducing manufacturing costs and having good practicality. However, this intake pipe is used at the intake end of a turbocharger, where the operating conditions differ from those of the intercooler intake end. The turbocharger intake pipe carries clean air, with a maximum operating temperature generally below 100℃ and a negative pressure, with a vacuum pressure as low as -0.01 MPa. In contrast, the intercooler intake end carries hot air that has not been cooled by the intercooler, with a maximum operating temperature between 180℃ and 250℃ and a maximum operating pressure between 0.3 MPa and 0.5 MPa. Therefore, directly using this intake pipe in the intercooler's intake system would not meet the requirements for high-temperature silicone tubing in terms of temperature resistance, pressure resistance, sealing performance, and connection reliability. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the purpose of this invention is to provide a high-temperature anti-adhesion silicone tube for intercoolers and its manufacturing method, so as to solve the problem that the inlet silicone tube of the intercooler adheres to the metal parts under high temperature and high pressure environment and has insufficient sealing performance.

[0006] This invention involves applying a high-temperature resistant insulating layer to the inner and outer surfaces of the connecting sections at both ends of the silicone tube, which are used to connect with metal clamps. The insulating layers are applied at locations corresponding to the locking connections with the metal clamps and metal pipe fittings. This prevents the silicone rubber tube and the tightly connected metal clamps and fittings from sticking together after prolonged operation at high temperatures. Furthermore, it prevents the rubber layer and reinforcing layer from peeling off during vehicle repair parts disassembly, allowing the intact silicone rubber tube to be reused repeatedly. The addition of a high-temperature anti-stick fluorosilicone strip on the inner side further enhances sealing.

[0007] Based on the above findings, this application provides the following technical solution:

[0008] In a first aspect, this application provides a high-temperature anti-sticking silicone tube, the silicone tube including connecting sections at both ends for connecting with metal clamps, and the tube wall corresponding to the connecting section includes, from the inside to the outside, a high-temperature resistant anti-sticking fluorosilicone strip, a silicone base layer and a high-temperature resistant aramid impregnated cloth.

[0009] By utilizing the excellent high-temperature resistance of aramid material and the aramid fabric mesh structure to reduce the contact area with metal clamps, high-temperature resistant aramid impregnated cloth is applied to the outside of the silicone base layer, serving as an isolation and anti-adhesion measure at the contact point with the metal clamps. The inner side of the connecting section pipe wall corresponding to the locking part of the metal clamp, due to its locking with the metal pipe joint, requires high sealing performance. This application utilizes the high chemical stability and poor adhesion of fluorosilicone to prevent it from adhering to the metal joint.

[0010] In some optional embodiments, the aforementioned silicone substrate comprises, from the inside out, an inner silicone layer, an aramid fiber reinforcement layer, and an outer silicone layer.

[0011] Because of its high strength, aramid fiber can effectively improve the strength and mechanical properties of the prepared silicone tube, preventing it from tearing easily during use and causing damage that would affect its normal operation. Furthermore, using aramid material to prepare the reinforcing layer allows the aramid fiber reinforcement layer to possess high strength, fire resistance, and anti-aging properties due to the inherent characteristics of aramid, thus enhancing the performance of the silicone material.

[0012] In some optional embodiments, the aramid fiber reinforcing layer includes an aramid fiber cloth and a silicone rubber layer, wherein the silicone rubber layer is applied to one side of the aramid fiber cloth.

[0013] In some alternative embodiments, the aramid fiber cloth is a poly(p-phenylene terephthalamide) aramid plain weave cloth, with a silicone rubber layer applied to one side on a three-roll calender.

[0014] In some optional embodiments, the high-temperature resistant aramid impregnated cloth is immersed in the impregnation solution through the aramid fiber cloth, so that the impregnation solution enters and remains in the mesh structure of the aramid fiber cloth, and the impregnation solution is RFL impregnation solution.

[0015] Secondly, this application provides a method for manufacturing a high-temperature anti-adhesion silicone tube, comprising the following steps:

[0016] S1: Wrap a layer of high-temperature resistant, non-stick fluorosilicone strip around the corresponding connecting section of the tubular core membrane.

[0017] S2: A silicone base layer is applied to the entire tubular core membrane, and the silicone base layer is applied to the outside of the high-temperature resistant and non-stick fluorosilicone strip.

[0018] In some alternative embodiments, an adhesive silicone transition layer is laminated onto the fluorosilicone sheet to enhance the bonding strength between the inner silicone layer and the fluorosilicone strip.

[0019] S3: Apply a layer of aramid-impregnated cloth to the outside of the silicone base layer at the connection section.

[0020] In some optional embodiments, the above-mentioned aramid-impregnated fabric is made by impregnation of a type aramid mesh fabric, wherein the impregnation solution is RFL impregnation solution.

[0021] S4: After the vulcanization reaction, cool and extract the above-mentioned tubular core membrane.

[0022] The high-temperature anti-adhesion silicone tube obtained by the above manufacturing method is less prone to peeling between the fluorosilicone layer and the inner silicone layer. The silicone rubber tube and the metal clamps and metal pipe joints that are tightly connected to it do not stick together after working at high temperature for a long time. When disassembling vehicle repair parts, the rubber layer and the reinforcing layer of the silicone rubber tube do not peel apart. The silicone rubber tube that remains intact after disassembly can be reused. In addition, the high-temperature anti-adhesion fluorosilicone strip laid on the inner side can improve the sealing between the pipes and solve the problem of the intercooler intake silicone tube sticking to metal parts under high temperature and high pressure environment and the problem of insufficient sealing. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a half-sectional structural diagram of a high-temperature anti-adhesion silicone tube according to the present invention;

[0025] Figure 2 This is a schematic diagram of the multilayer structure of a high-temperature anti-adhesion silicone tube according to the present invention;

[0026] Figure 3 This is a flowchart illustrating the manufacturing method of a high-temperature anti-adhesion silicone tube according to the present invention.

[0027] In the diagram: 1. Silicone base layer; 11. Inner silicone layer; 12. Aramid fiber reinforcement layer; 13. Outer silicone layer; 2. High-temperature resistant aramid impregnated cloth; 3. High-temperature resistant anti-stick fluorosilicone strip; 4. Tubular core film; 5. Steel wire reinforcing ring. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] An intercooler is typically located between the turbocharger outlet and the intake manifold. For turbocharged engines, the intercooler is a crucial component of the turbocharging system. Both supercharged and turbocharged engines require an intercooler between the turbocharger and the intake manifold. The intercooler lowers the temperature of the air entering the cylinders, increases air density, and enhances oxygen content, thereby increasing combustion efficiency, engine power output, and fuel economy.

[0030] Therefore, when connecting the intercooler and the turbocharger, the air entering the intercooler is hot air output from the turbocharger, with a maximum operating temperature between 180℃ and 250℃ and a maximum operating pressure between 0.3MPa and 0.5MPa. This not only requires high-temperature anti-sticking properties for the connecting pipes, but also pressure resistance and better sealing.

[0031] The applicant discovered that if the rubber hose in prior art 1 is directly connected to the metal pipe joint of the intercooler's intake pipe and locked with a metal clamp, the main chain of silicone rubber molecules (-Si-O-) is generally not very polar and has low reactivity, making it difficult to form an effective bond with the metal surface. However, the intake temperature of heavy-duty commercial vehicle engines can reach over 200°C. Under continuous high temperatures, the silicone rubber molecules, residual vulcanizing agents, silane coupling agents, and metal oxides on the metal surface become significantly more active. Through their interaction, the rubber layer and the metal surface not only form a physical mechanical interlock, but also generate strong chemical bonds between free radicals produced after the dehydrogenation of polydimethylsiloxane molecules, silane coupling agents, and surface-active substances. When this bond strength exceeds the adhesive strength between the rubber layer and the fiber reinforcement layer of the silicone rubber hose, removing the metal clamp or metal fitting causes the rubber layer to adhere to the tightly contacting metal part while peeling off from the fiber reinforcement layer, rendering the silicone hose unusable after disassembly.

[0032] However, if the intake pipe in the existing technology 2 is directly installed at the air inlet of the intercooler, unlike the turbocharger intake pipe which operates at a negative pressure, the negative pressure can be used to ensure the sealing between the intake pipe and the intake end. Since the intercooler intake end transmits hot air that has not been cooled by the intercooler, its maximum operating temperature is between 180℃ and 250℃, and its maximum operating pressure is between 0.3MPa and 0.5MPa, making the intake pipe unable to meet the sealing requirements under high temperature and positive pressure conditions.

[0033] like Figures 1 to 2 As shown, this application provides a high-temperature anti-adhesion silicone tube, which can solve the problem of traditional silicone tubes being unable to be disassembled after long-term use. The high-temperature anti-adhesion silicone tube provided by this application includes connecting sections at both ends for connecting to the intercooler intake end and the turbocharger outlet, respectively. The tube wall corresponding to the connecting section includes, from the inside to the outside, a high-temperature resistant anti-adhesion fluorosilicone strip 3, a silicone base layer 1, and a high-temperature resistant aramid impregnated cloth 2.

[0034] Specifically, a high-temperature resistant, non-stick fluorosilicone strip 3 is applied to the inner side of the aforementioned silicone base layer 1, and a high-temperature resistant aramid-impregnated cloth 2 is applied to the outer side of the aforementioned silicone base layer 1. The section between the two connecting sections is the main body section, and the pipe wall corresponding to the main body section is the silicone base layer 1.

[0035] In this example, the high-temperature resistant aramid impregnated cloth 2 is immersed in the impregnation solution through the aramid fiber cloth, so that the impregnation solution enters and remains in the mesh structure of the aramid fiber cloth.

[0036] It is understandable that, due to the excellent high-temperature resistance of aramid materials, the aramid cloth mesh structure reduces the contact area with the metal clamps. High-temperature resistant aramid impregnated cloth 2 is applied to the outside of the silicone base layer 1, and the silicone tube is fitted onto the interface and tightened with metal clamps. This provides isolation and prevents adhesion at the contact points of the metal clamps when the silicone tube connects to the intercooler intake and turbocharger outlet. However, the inner side of the connecting section corresponding to the metal clamp locking area requires high sealing performance; therefore, aramid fiber cloth cannot be used for isolation. This application utilizes the high chemical stability and poor adhesion of fluorosilicone to prevent it from adhering to the metal joint.

[0037] Therefore, by applying high-temperature resistant anti-stick fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 to the inner and outer sides of the silicone base layer 1 respectively as high-temperature resistant isolation layers, and by ensuring that the application positions of the high-temperature resistant anti-stick fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 correspond to the positions of the metal clamps locking the metal pipe joints, the silicone tube and the metal clamps and metal pipe joints that are tightly connected to it do not stick together after working at high temperatures for a long time. When disassembling vehicle repair parts, the rubber layer and the reinforcing layer of the silicone tube do not peel off, and the intact silicone tube can be reused repeatedly after disassembly.

[0038] In some optional embodiments, the silicone base layer 1 comprises, from the inside out, an inner silicone layer 11, an aramid fiber reinforcing layer 12, and an outer silicone layer 13.

[0039] It is understandable that aramid fibers have high strength, which can effectively improve the strength and mechanical properties of the prepared silicone tubes, preventing them from easily tearing during use and causing damage that would affect their normal use. Simultaneously, using aramid materials to prepare the reinforcing layer allows the aramid fiber reinforcing layer 12 to possess high strength, fire resistance, and anti-aging properties due to the inherent characteristics of aramid, thereby enhancing the performance of the silicone material.

[0040] In the main body section of the silicone tube, the corresponding tube wall is a silicone base layer 1 comprising an inner silicone layer 11, an aramid fiber reinforcement layer 12, and an outer silicone layer 13, and is shaped into a specific curved form according to design requirements. In this example, the main body section has multiple upward-facing arc-shaped arches, with steel wire reinforcing rings 5 ​​placed in the recesses between adjacent arc-shaped arches to strengthen the structure of the main body section and provide it with a certain degree of elasticity. Because the aramid fiber reinforcement layer 12 has a knitted structure, it allows for a large deformation along the tube's axial direction, making it easy to bend and allowing for a larger bending angle, which is beneficial for the formation of the arc-shaped arch structure. Simultaneously, the inner and outer silicone layers ensure that the strength of the bent parts meets the requirements.

[0041] In some optional embodiments, the aramid fiber reinforcing layer 12 includes an aramid fiber cloth and a silicone rubber layer, wherein the silicone rubber layer is applied to one side of the aramid fiber cloth.

[0042] Optionally, the aramid fiber cloth is made of type 1414 (poly(p-phenylene terephthalamide)) aramid plain weave cloth, and a silicone rubber layer is applied to one side on a three-roll calender.

[0043] Preferably, the aramid fiber reinforcing layer 12 has three layers, which are evenly wound between the inner silicone layer 11 and the outer silicone layer 13.

[0044] In this example, the inner silicone layer 11 and the outer silicone layer 13 are made of Wacker Chemie R270 silicone rubber with a thickness of 1.0 mm. The high-temperature resistant aramid impregnated cloth 2 is made of 1313 type (poly(m-phenylene isophthalamide)) impregnated aramid plain weave cloth, and the impregnation solution is RFL impregnation solution (phenolic resin + butadiene-pyridine latex). The high-temperature resistant anti-stick fluorosilicone strip 3 is made of Dow 5785-55 high-temperature resistant fluorosilicone.

[0045] In some optional embodiments, the high-temperature resistant anti-stick fluorosilicone strip 3 and the high-temperature resistant aramid impregnated cloth 2 are bonded by high-temperature vulcanization.

[0046] On the other hand, such as Figure 3As shown, this application also provides a method for manufacturing a high-temperature anti-adhesion silicone tube, comprising the following steps:

[0047] S1: Wrap a layer of high-temperature resistant, non-stick fluorosilicone strip 3 around the connecting section corresponding to the tubular core membrane 4.

[0048] It is understandable that the tubular core membrane 4 is selected according to the size of the silicone tube to be processed, and the high-temperature resistant and non-stick fluorosilicone strip 3 is evenly wrapped at the corresponding connection sections at both ends of the tubular core membrane 4.

[0049] In some optional embodiments, the high-temperature resistant anti-stick fluorosilicone strip 3 is combined with an adhesive transition silicone layer, and after being rolled, cut and wound around the connecting section. The adhesive transition silicone layer is located on the side of the high-temperature resistant anti-stick fluorosilicone strip 3 away from the tubular core film 4, so as to be bonded to the inner silicone layer 11 that will be applied subsequently.

[0050] In other words, the aforementioned adhesive transition silicone layer is located between the inner silicone layer 11 and the high-temperature resistant, non-stick fluorosilicone strip 3. The adhesive transition silicone layer improves the adhesion strength between the inner silicone layer 11 and the high-temperature resistant, non-stick fluorosilicone strip 3, preventing peeling between them.

[0051] Preferably, the high-temperature resistant anti-stick fluorosilicone strip 3 is made of high-temperature resistant fluorosilicone, and the thickness of the adhesive transition silicone layer is the same as the thickness of the high-temperature resistant anti-stick fluorosilicone strip 3.

[0052] In this example, the high-temperature resistant and non-stick fluorosilicone strip 3 is made of Weihai Xinyuan NFS9360 high-temperature resistant fluorosilicone. It is made into a 0.5mm thick sheet using a three-roll calender, and a 0.5mm thick adhesive silicone transition layer is laminated onto the fluorosilicone sheet using a calender.

[0053] S2: A silicone base layer 1 is applied to the tubular core membrane 4, and the silicone base layer 1 is applied to the outside of the high-temperature resistant and non-stick fluorosilicone strip 3.

[0054] In some optional embodiments, the silicone base layer 1 comprises, from the inside out, an inner silicone layer 11, an aramid fiber reinforcing layer 12, and an outer silicone layer 13.

[0055] In some optional embodiments, the aramid fiber reinforcing layer 12 includes an aramid fiber cloth and a silicone rubber layer, wherein the silicone rubber layer is applied to one side of the aramid fiber cloth.

[0056] Optionally, the aramid fiber cloth is made of type 1414 (poly(p-phenylene terephthalamide)) aramid plain weave cloth, and a silicone rubber layer is applied to one side on a three-roll calender.

[0057] Preferably, the aramid fiber reinforcing layer 12 has three layers, which are evenly wound between the inner silicone layer 11 and the outer silicone layer 13.

[0058] S3: Apply a layer of high-temperature resistant aramid impregnated cloth 2 to the outside of the silicone base layer 1 located at the connecting section.

[0059] In some optional embodiments, the above-mentioned high-temperature resistant aramid impregnated cloth 2 is made by impregnating a 1313 type aramid mesh cloth with an RFL impregnating solution.

[0060] In some optional embodiments, both the high-temperature resistant anti-stick fluorosilicone strip 3 and the high-temperature resistant aramid impregnated cloth 2 are bonded by high-temperature vulcanization.

[0061] S4: After the vulcanization reaction, cool and extract the above-mentioned tubular core membrane 4.

[0062] Specifically, the sulfidation conditions for the above-mentioned sulfidation reaction are as follows:

[0063] The vulcanization temperature is 150-200℃, the vulcanization time is 20-30min, and the vulcanizing agent is an organic peroxide DCP (diisopropylbenzene peroxide). The above-mentioned high-temperature resistant anti-stick fluorosilicone strip 3 and the above-mentioned impregnation solution participate in the vulcanization reaction simultaneously.

[0064] After the tubular core membrane 4 is extracted, steel wire reinforcing rings 5 ​​are added circumferentially at equal intervals on the main body section according to the design requirements of the silicone tube, and then the tube is packed and stored.

[0065] Example 1

[0066] The manufacturing method of the high-temperature anti-adhesion silicone tube provided in this embodiment includes:

[0067] (1) Wrap a layer of high-temperature resistant, non-stick fluorosilicone strip 3 around the connecting section corresponding to the tubular core membrane 4.

[0068] The high-temperature resistant, non-stick fluorosilicone strip 3 is made of Dow 5785-55 high-temperature resistant fluorosilicone, which is formed into a 0.8mm thick sheet by a three-roll calender, and then cut into 45mm wide strips and rolled for later use.

[0069] (2) A silicone base layer 1 is applied to the tubular core membrane 4 as a whole, and the silicone base layer 1 is applied to the outside of the high temperature resistant and non-stick fluorosilicone strip 3.

[0070] The aforementioned silicone base layer 1 comprises, from the inside out, an inner silicone layer 11, an aramid fiber reinforcing layer 12, and an outer silicone layer 13.

[0071] The inner silicone layer 11 and the outer silicone layer 13 are made of R270 grade silicone rubber from Wacker Chemie AG, Germany, and are produced into 1.0 mm thick sheets using a three-roll calender.

[0072] The aramid fiber reinforcement layer 12 uses commercially available 1414 type (poly(p-phenylene terephthalamide)) aramid plain weave fabric 20*20, and a silicone rubber layer with a thickness of 0.8mm and a width of 1m is hung on one side on a 3-roll calender. It is then cut to the appropriate width according to the product size for later use.

[0073] (3) Apply a layer of high-temperature resistant aramid impregnated cloth 2 to the outside of the silicone base layer 1 located at the connection section.

[0074] High-temperature resistant aramid dipped cloth 2, made of commercially available 1313 type (poly(m-phenylene isophthalamide)) pre-impregnated aramid 20*20 plain weave cloth, the impregnation solution is RFL impregnation liquid (phenolic resin + butadiene-pyridine latex), weight 125g, thickness 0.8mm, cut into 22mm wide strips.

[0075] (4) Place the above-formed rubber hose semi-finished product in a vulcanizing tank for vulcanization.

[0076] The vulcanization conditions are as follows: vulcanization temperature 175℃, vulcanization time 25min, and the vulcanizing agent is an organic peroxide DCP (diisopropylbenzene peroxide), which initiates free radical cross-linking between rubber molecules to complete the vulcanization. Fluorosilicone and the impregnation solution also participate in the vulcanization reaction.

[0077] Example 2

[0078] The manufacturing method of the high-temperature anti-adhesion silicone tube provided in this embodiment includes:

[0079] (1) Wrap a layer of high-temperature resistant, non-stick fluorosilicone strip 3 around the connecting section corresponding to the tubular core membrane 4.

[0080] The high-temperature resistant and non-stick fluorosilicone strip 3 uses Weihai Xinyuan NFS9360 high-temperature resistant fluorosilicone. It is made into a 0.5mm thick sheet using a three-roll calender, and a 0.5mm thick adhesive silicone transition layer is laminated onto the fluorosilicone sheet using a calender.

[0081] The tackifying silicone can be Wacker Chemie R401 from Germany, cut into 45mm wide strips and rolled up for later use. During molding, the tackifying silicone transition layer is placed on the outside of the high-temperature resistant, non-stick fluorosilicone strip 3, away from the tubular core film 4, to be applied with the subsequent inner silicone layer 11. Tests have shown that adding the tackifying silicone transition layer can increase the adhesion strength between the inner silicone layer 11 and the high-temperature resistant, non-stick fluorosilicone strip 3 by more than 30%.

[0082] (2) A silicone base layer 1 is applied to the tubular core membrane 4 as a whole, and the silicone base layer 1 is applied to the outside of the high temperature resistant and non-stick fluorosilicone strip 3.

[0083] The aforementioned silicone base layer 1 comprises, from the inside out, an inner silicone layer 11, an aramid fiber reinforcing layer 12, and an outer silicone layer 13. Furthermore, the tackifying silicone transition layer is positioned between the inner silicone layer 11 and the high-temperature resistant, non-stick fluorosilicone strip 3.

[0084] The inner silicone layer 11 and the outer silicone layer 13 are made of R270 grade silicone rubber from Wacker Chemie AG, Germany, and are produced into 1.0 mm thick sheets using a three-roll calender.

[0085] The aramid fiber reinforcement layer 12 uses commercially available 1414 type (poly(p-phenylene terephthalamide)) aramid plain weave fabric 20*20, and a silicone rubber layer with a thickness of 0.8mm and a width of 1m is hung on one side on a 3-roll calender. It is then cut to the appropriate width according to the product size for later use.

[0086] (3) Apply a layer of high-temperature resistant aramid impregnated cloth 2 to the outside of the silicone base layer 1 located at the connection section.

[0087] High-temperature resistant aramid impregnated cloth 2, using commercially available 1313 type (poly(m-phenylene isophthalamide)) impregnated aramid mesh cloth, the impregnation solution is RFL impregnation liquid (phenolic resin + butadiene-pyridine latex), weight 130 g / m², thickness 0.6 mm, cut into 22 mm wide strips.

[0088] (4) Place the above-formed rubber hose semi-finished product in a vulcanizing tank for vulcanization.

[0089] The vulcanization conditions are as follows: vulcanization temperature 175℃, vulcanization time 25min, and the vulcanizing agent is an organic peroxide DCP (diisopropylbenzene peroxide), which initiates free radical cross-linking between rubber molecules to complete the vulcanization. Fluorosilicone and the impregnation solution also participate in the vulcanization reaction.

[0090] Comparison of test data between the embodiments and existing technologies:

[0091]

[0092] The peel strength test in the table is performed according to the test method for type 8 specimens in GB / T 14905-2009 Rubber and Plastic Hoses—Determination of Interlayer Adhesion Strength. ， Peel strength was tested. Hot air aging tests were conducted according to the national standard GB / T 3512-2014, "Accelerated Aging and Heat Resistance Test Methods for Vulcanized Rubber or Thermoplastic Rubber".

[0093] It should be noted that the film used in the experiment did not have high-temperature resistant, anti-sticking fluorosilicone strips between its inner lining layers, therefore peel strength was not tested, and no experimental results regarding peel strength are available.

[0094] The experimental samples in Examples 1 and 2 were the silicone tube parts from Examples 1 and 2 of this application, and were assembled according to the actual vehicle installation state. That is, both ends of the silicone tube were respectively fitted onto the steel tubular joint at the air intake end of the intercooler and the steel tubular joint at the outlet of the turbocharger, and then the connection section was locked with metal clamps. After the hot air aging test time was completed, the metal clamps were removed and the metal tubular joints were unloaded. It was observed whether there was peeling of the inner silicone layer, outer silicone layer or fiber reinforcement layer at the connection section of the silicone tube, and it was also observed whether there was adhesion of the inner silicone layer, outer silicone layer or fiber reinforcement layer at the corresponding connection section of the metal parts.

[0095] The experimental results shown in the table demonstrate that the silicone tubes of Examples 1 and 2 of this invention, due to the application of high-temperature resistant, non-stick fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 as high-temperature isolation layers on the inner and outer sides of the silicone base layer 1, effectively isolate high temperatures. Simultaneously, the fluorosilicone exhibits high chemical stability and poor adhesion, resulting in good anti-peeling performance between the fluorosilicone layer and the inner silicone layer. Particularly in Example 2, when an tackifying silicone transition layer is laminated onto the fluorosilicone sheet, and this transition layer is positioned between the inner silicone layer and the high-temperature resistant fluorosilicone during molding, the bonding strength between the inner silicone layer and the fluorosilicone is significantly improved. Even when external force is applied until the test sheet breaks, the inner silicone layer and the fluorosilicone layer do not detach.

[0096] Regarding hot air aging, after 168 hours at 250°C, the activity of silicone rubber molecules, residual vulcanizing agents, silane coupling agents, and metal oxides on the metal surface is greatly enhanced due to the prolonged exposure to high temperatures in existing silicone rubber films. This causes the rubber layer to adhere to the closely contacting metal parts, resulting in the peeling of the inner and outer rubber layers and the reinforcing layer of the silicone rubber tube. In the high-temperature anti-adhesion silicone tubes of Embodiments 1 and 2 of this invention, high-temperature resistant anti-adhesion fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 are applied to the inner and outer sides of the silicone base layer 1 as high-temperature resistant isolation layers, effectively isolating it from high temperatures. Furthermore, the application positions of the high-temperature resistant anti-adhesion fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 correspond to the positions where the metal clamps lock the metal pipe joints. This prevents adhesion between the silicone tube and the closely connected metal clamps and metal pipe joints after prolonged operation at high temperatures, thus avoiding the problem of peeling between the inner and outer rubber layers.

[0097] Therefore, by using the high-temperature anti-adhesion silicone tube of the present invention, high-temperature resistant anti-adhesion fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 are respectively applied to the inner and outer sides of the silicone base layer 1 as high-temperature resistant isolation layers. The application positions of the high-temperature resistant anti-adhesion fluorosilicone strips 3 and high-temperature resistant aramid impregnated cloth 2 correspond to the positions of the metal clamps locking the metal pipe joints. A layer of tackifying silicone transition layer is laminated on the fluorosilicone sheet, so that the tackifying silicone transition layer is placed between the high-temperature resistant anti-adhesion fluorosilicone strips 3 and the inner silicone layer 11, thereby greatly improving the anti-peeling performance of the inner and outer adhesive layers.

[0098] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0099] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0100] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A high-temperature anti-adhesion silicone tube, characterized in that, It includes a connecting section at both ends for connecting to the intercooler intake and the turbocharger outlet, respectively, and the pipe wall corresponding to the connecting section includes: Silicone base layer (1); High-temperature resistant, non-stick fluorosilicone strip (3) is applied to the inner side of the silicone base layer (1); High-temperature resistant aramid impregnated cloth (2) is applied to the outside of the silicone base layer (1); The silicone base layer (1) consists of an inner silicone layer (11), an aramid fiber reinforcement layer (12), and an outer silicone layer (13) from the inside to the outside. The aramid fiber reinforcement layer (12) includes an aramid fiber cloth and a silicone rubber layer, wherein the silicone rubber layer is applied to one side of the aramid fiber cloth. The high-temperature anti-adhesion silicone tube is manufactured using the following method, including the following steps: A layer of high-temperature resistant, non-stick fluorosilicone strip (3) is wrapped around the connecting section corresponding to the tubular core membrane (4); A silicone base layer (1) is applied to the tubular core membrane (4), and the silicone base layer (1) is applied to the outside of the high-temperature resistant and non-stick fluorosilicone strip (3); A layer of high-temperature resistant aramid impregnated cloth (2) is applied to the outside of the silicone base layer (1) located at the connecting section. After the vulcanization reaction, the tubular core membrane is cooled and extracted.

2. The high-temperature anti-adhesion silicone tube as described in claim 1, characterized in that, The integral application of silicone base layer (1) on tubular core membrane includes an inner silicone layer (11), an aramid fiber reinforcement layer (12), and an outer silicone layer (13) applied sequentially from the inside to the outside.

3. The high-temperature anti-adhesion silicone tube as described in claim 2, characterized in that, The aramid fiber reinforcement layer (12) is made by attaching a silicone rubber layer to one side of a 1414 type aramid plain weave cloth on a roller calender.

4. The high-temperature anti-adhesion silicone tube as described in claim 1, characterized in that, The high-temperature resistant aramid impregnated cloth (2) is made by impregnating 1313 type aramid mesh cloth.

5. The high-temperature anti-adhesion silicone tube as described in claim 2, characterized in that, The high-temperature resistant, non-stick fluorosilicone strip (3) is combined with the adhesive transition silicone layer and wound around the connecting section after being stretched and cut. The adhesive transition silicone layer is located between the inner silicone layer (11) and the high-temperature resistant, non-stick fluorosilicone strip (3).

6. The high-temperature anti-adhesion silicone tube as described in claim 5, characterized in that, The high-temperature resistant anti-stick fluorosilicone strip (3) is made of high-temperature resistant fluorosilicone, and the thickness of the adhesive transition silicone layer is the same as the thickness of the high-temperature resistant anti-stick fluorosilicone strip (3).

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