Composite insulating sealing rubber belt and preparation process thereof
By using nano-zirconia and carbon fiber hot-pressing composite technology to form an embedded composite structure, the problems of self-adhesion, mechanical properties and insulation performance of insulating sealing rubber tape are solved, and stable use is achieved in complex scenarios and extreme working conditions.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHU GROUP CO LTD
- Filing Date
- 2026-05-09
- Publication Date
- 2026-06-26
AI Technical Summary
Existing insulating and sealing rubber tapes have many problems in terms of self-adhesion and stability, mechanical properties, production costs, compatibility, adaptability to complex environments and extreme working conditions, which have not been effectively solved, especially the problems of self-adhesion, flame retardancy, wear resistance and anti-aging properties.
By employing nano-zirconia and carbon fiber hot-pressing composite technology, an embedded composite structure is formed. Stable self-adhesion is achieved through molecular hook anchoring-restricted wetting-chain segment entanglement mechanism, which enhances mechanical properties, improves insulation performance and durability.
It achieves stable self-adhesion, excellent mechanical properties, stable insulation performance, significantly enhanced durability, adaptability to extreme working conditions, and high economic efficiency, making it suitable for complex scenarios such as high-voltage electrical equipment and subway tunnels.
Smart Images
Figure CN122278367A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of insulating and sealing materials technology, specifically relating to a composite insulating and sealing rubber strip suitable for complex scenarios such as high-voltage electrical equipment, subway tunnels, and oil-bearing strata. It can achieve integrated sealing and insulation functions and meet the needs of use under extreme working conditions. Background Technology
[0002] Currently, insulating sealing rubber tapes are widely used in electrical equipment, tunnel engineering, oil and gas extraction, and other fields. Their core function is to achieve sealing protection and insulation isolation. In existing technologies, insulating sealing rubber tapes mostly use silicone rubber or EPDM rubber as the base material. To meet the requirements for self-adhesion, flame retardancy, and other performance characteristics, boron-based tackifiers or single high-efficiency flame retardants are usually added.
[0003] The relevant existing technologies have the following significant drawbacks: 1. Conflict between self-adhesion and stability: Products with added boron-based tackifiers are prone to hydrolysis after 6-9 months of storage, precipitating white needle-like substances, which significantly reduces self-adhesion and fails to meet the requirements for long-term storage and use; 2. Imbalance in mechanical properties: In order to meet the flame retardant standard, some products have significantly increased the amount of flame retardant added, resulting in high hardness of the rubber belt, insufficient elongation at break, and poor flexibility and resistance to deformation. 3. Conflict between production cost and performance: The high price of some high-performance modified raw materials leads to high production and manufacturing costs, or sacrifices performance under extreme conditions such as oil resistance and high temperature resistance in order to control costs; 4. Compatibility and interfacial bonding issues: Some product substrates have poor compatibility with polar fillers, resulting in uneven dispersion and poor interfacial bonding, which affects the overall performance stability. 5. Insufficient adaptability to complex environments: In complex environments such as high humidity and strong ultraviolet radiation, the insulation performance is easily degraded, and the interlayer bonding strength is insufficient. Long-term use can easily lead to delamination, aging and cracking. 6. Poor adaptability to extreme working conditions: The high and low temperature adaptability range is limited to the conventional -40℃~120℃, and the wear resistance and fatigue resistance performance is difficult to meet the long-term use requirements under extreme working conditions.
[0004] The aforementioned shortcomings of existing technologies severely restrict the application effect of insulating and sealing rubber tapes in complex scenarios and extreme working conditions, and there is an urgent need for a technical solution that can balance various performance aspects and take into account both practicality and economy. Summary of the Invention
[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a composite insulating and sealing rubber tape and its preparation process to solve the problems mentioned in the above-mentioned technical background.
[0006] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a composite insulating and sealing rubber tape, the rubber tape comprising a substrate layer and a composite reinforcing layer stacked sequentially; The nano-zirconia and carbon fiber in the composite reinforcement layer are partially pressed into and embedded in the shallow surface layer of the substrate layer during the hot-pressing composite stage, forming an embedded composite structure with the substrate layer. The substrate layer, by weight, is composed of the following components: 40-60 parts of methyl vinyl silicone rubber, 20-30 parts of hydrogenated nitrile rubber, 15-25 parts of composite filler modified with silane coupling agent KH-590, 2-4 parts of vulcanizing agent, 1-3 parts of antioxidant, and 3-6 parts of softener; wherein the composite filler includes a flame retardant component and a reinforcing component, and the weight ratio of the flame retardant component to the reinforcing component is 2:1 to 3:1; In the composite reinforcing layer, the amount of nano-zirconia added is 3-8 parts, and the amount of carbon fiber added is 2-5 parts.
[0007] Preferably, the vulcanizing agent is dicumyl peroxide.
[0008] Preferably, the antioxidant is antioxidant RD.
[0009] Preferably, the softener is dioctyl phthalate (DOP).
[0010] Preferably, the purity of the silane coupling agent KH-590 is above 98%.
[0011] Preferably, the flame-retardant component is a halogen-free flame retardant, and the reinforcing component is hydrated nano-silica. More preferably, the halogen-free flame retardant is a novel halogen-free environmentally friendly flame retardant produced by Hefei Zhongke Flame Retardant New Materials Co., Ltd.; and the hydrated nano-silica is the SR series hydrated nano-silica produced by Quecheng Silicon Chemical Co., Ltd., brand name AFSIL®SR210.
[0012] More preferably, the weight ratio of the flame retardant component to the reinforcing component is 2.5:1.
[0013] Preferably, the purity of the nano-zirconia is 99.9%. More preferably, the nano-zirconia is YT-ZrO2-01 type nano-zirconia produced by Ningbo Yutian Materials Technology Co., Ltd., with a purity of 99.9%. Preferably, the carbon fiber is a short-cut carbon fiber with a length of 3mm. More preferably, the carbon fiber is CF-3K type short-cut carbon fiber with a length of 3mm produced by Jiangsu Hengshen Co., Ltd.
[0014] Preferably, the composite reinforcing layer is prepared by mixing nano-zirconia and carbon fiber and then laying it on the surface of the substrate layer, and hot-pressing it at 140-150℃ and 5-8MPa for 10-15 minutes; after the hot-pressing, the surface of the uncured substrate layer is deformed, so that the nano-zirconia and carbon fiber are partially embedded in the shallow surface of the substrate layer, and after curing and shaping, the inlaid composite structure is formed.
[0015] The present invention also provides a preparation process for the above-mentioned composite insulating and sealing rubber tape, comprising the following steps: S1. Modification of Composite Filler: Add the composite filler to a high-speed mixer, heat to 80-90℃, add 0.5-1.5% by weight of silane coupling agent KH-590, stir at 300-500 r / min for 30-60 min, and cool to room temperature after modification for later use. In this step, the silane coupling agent KH-590 containing mercapto groups is selected. On the one hand, its alkoxy groups can efficiently condense with the hydroxyl groups on the surface of hydrated nano-silica, significantly reducing the surface energy of the filler. On the other hand, its mercapto groups can undergo free radical addition with the residual double bonds in hydrogenated nitrile rubber under the initiation of peroxide. At the same time, its long-chain carbon skeleton has good physical entanglement compatibility with methyl vinyl silicone rubber, thereby building a stable filler-substrate interface bridge in the complex blend system.
[0016] S2. Matrix material blending: Methyl vinyl silicone rubber and hydrogenated nitrile rubber are added to an internal mixer in proportion and mixed for 15-20 minutes at a temperature of 120-130℃ and a speed of 60-80 r / min to obtain a blended matrix material; S3. Component mixing: Add the S1 modified composite filler, antioxidant, and softener to the internal mixer in proportion, and continue mixing for 20-30 minutes at a temperature of 110-120℃ and a speed of 50-70r / min. Then add the vulcanizing agent, cool down to 80-90℃, stir for 10-15 minutes, and mix evenly to obtain the rubber compound. S4. Reinforcing Layer Composite: The rubber compound obtained in S3 is fed into an open mill and calendered into a substrate layer with a thickness of 2-3 mm. Then, nano-zirconia and carbon fibers are mixed uniformly in a specific ratio and laid on the surface of the substrate layer. Hot-pressing is then performed at 140-150℃ and 5-8 MPa for 10-15 minutes. This composite reinforcing layer is not a suspended, independent, pure inorganic layer, nor is it a traditional adhesive laminate structure. During the hot-pressing process in step S4, the substrate layer is in an uncured, highly elastic state. Under pressure, the surface undergoes plastic deformation, causing the nano-zirconia and chopped carbon fibers to be partially pressed into and embedded within the shallow surface of the substrate. After curing and setting, the rubber matrix tightly encapsulates the reinforcing phase, forming a mechanical anchoring structure. This structure maintains the high wear resistance and fatigue resistance of the surface layer while eliminating the inherent physical weak interfaces in traditional laminate structures. This results in the failure mode during peel testing being cohesive failure of the rubber matrix, fundamentally avoiding the risk of delamination.
[0017] S5. Vulcanization treatment: (1) First vulcanization: The semi-finished product after S4 composite is sent into the vulcanizing machine at a temperature of 160±3℃, a pressure of 10-12MPa, and a vulcanization time of 15-20min; (2) Secondary vulcanization: The product after primary vulcanization is sent into an oven at a temperature of 180±2℃ for 4-6 hours. S6. Post-processing: After vulcanization, cool to room temperature, then cut and trim to obtain the finished composite insulating and sealing rubber tape.
[0018] Compared with the prior art, the beneficial effects of the present invention are: 1. Significant leap in core performance: (1) Stable self-adhesion and breakthrough of traditional tackifier dependence: This invention abandons the traditional easily hydrolyzed chemical tackifiers and breaks through the technical prejudice that "no tackifier, no self-adhesion". It innovatively achieves stable self-adhesion through a triple physical and chemical synergistic mechanism of "molecular hook anchoring - restricted wetting - chain segment entanglement". First, the KH-590 long-chain alkyl group on the surface of the modified filler forms a reversible physical entanglement "molecular hook" at room temperature, providing pressure-sensitive adhesion force; second, a trace amount of softener DOP forms a nanoscale restricted wetting layer on the surface under the adsorption of the filler, giving it initial tack and no macroscopic oil stains are released after accelerated aging test at 70℃ for 7 days; third, the vinyl segments of methyl vinyl silicone rubber in the micro-region of the substrate surface maintain high flexibility, realizing spontaneous entanglement at the bonding interface. This non-chemical tackifier system completely eliminates the drawback of boron-based substances releasing white needle-like substances after hydrolysis, and the self-adhesion retention rate is stable for a long time.
[0019] (2) Excellent mechanical properties: The synergistic effect of the substrate blend and the reinforcing layer composite increases the elongation at break to over 450%, and greatly enhances the flexibility and resistance to deformation. (3) Stable insulation performance: The insulation performance decays with low temperature in a wide temperature range (-50℃~150℃), meeting the insulation requirements of extreme environments.
[0020] 2. Significantly enhanced durability: (1) Strong interlayer adhesion: The traditional surface coating or adhesive bonding process is abandoned. The inorganic reinforcing phase is embedded into the substrate through hot pressing and embedding process to form an interface-free mechanical anchor. The interlayer peel strength is tested to be ≥8kN / m, and the failure mode is cohesive failure of the rubber body (i.e., tearing occurs inside the rubber rather than at the interface), which completely eliminates the delamination problem under complex working conditions; (2) Fatigue resistance and wear resistance: after 10 6 The elastic recovery rate in the reciprocating deformation test is ≥95%, and the wear amount in the wear resistance test is ≤0.08g, demonstrating excellent fatigue resistance and wear resistance. (3) Good aging stability: after 2000 hours of hot air aging, the tensile strength decreases by less than 6%, and the service life is significantly extended compared with traditional products.
[0021] 3. Balancing practicality and economy: (1) High overall cost performance: Through the hot-pressed inlay composite structure design, this invention can effectively extend the service life while ensuring high performance under extreme working conditions, and its overall cost performance is better than that of traditional products.
[0022] (2) Process compatibility: The processing technology is highly compatible with existing equipment, requiring no additional special equipment, which facilitates industrial production; (3) Convenient construction: The integrated sealing and insulation effect is outstanding, the construction operation is simple, and it can meet the installation needs of complex scenarios. Attached Figure Description
[0023] Figure 1 This is a product image of the composite insulating and sealing rubber tape described in this invention; Figure 2 This is a detailed unfolded view of the composite insulating and sealing rubber tape described in this invention; Figure 3 This is a picture of a new type of halogen-free environmentally friendly flame retardant. Detailed Implementation
[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.
[0025] In this embodiment of the application, some of the raw materials are sourced from the following sources: The methyl vinyl silicone rubber selected is MVQ-110 type (high vinyl content type, such as model 110-7) produced by Dongjue Organosilicon Group Co., Ltd. The hydrogenated nitrile butadiene rubber used is HNBR-35 (hydrogenation degree 90%+) produced by Shandong Dawn Polymer Co., Ltd. The silane coupling agent KH-590 is an industrial-grade product (purity 98%+) manufactured by Hubei Xingyan New Material Technology Co., Ltd. A novel halogen-free, environmentally friendly flame retardant, purchased from Hefei Zhongke Flame Retardant New Materials Co., Ltd. A picture of the raw material is shown below. Figure 3 As shown; SR series hydrated nano silica, brand name AFSIL®SR210, purchased from Quecheng Silicon Chemical Co., Ltd. The nano-zirconia used is YT-ZrO2-01 (nano-grade, 99.9% purity) produced by Ningbo Yutian Materials Technology Co., Ltd. The carbon fiber used is CF-3K type (short-cut type, 3mm in length) produced by Jiangsu Hengshen Co., Ltd. The vulcanizing agent selected is DCP-40 (40% content, calcium carbonate carrier) produced by Shandong Yanggu Huatai Chemical Co., Ltd. Antioxidant RD, chemical name: 2,2,4-trimethyl-1,2-dihydroquinoline polymer, CAS No.: 26780-96-1, purchased from Shandong Shangshun Chemical Co., Ltd. The softener used was dioctyl phthalate (DOP), purchased from Zhongshan Liancheng Chemical Industry Co., Ltd.
[0026] Further explanation of the triple synergistic mechanism of "self-adhesion" in the tackifier-free system of this invention: In conventional understanding, removing the tackifying resin will cause the rubber tape to lose its self-adhesive properties. However, this invention, through the ingenious design of specific components and microstructure, achieves excellent and durable self-adhesive properties without adding any traditional tackifiers. This is not due to a single chemical adhesion mechanism, but rather the synergistic effect of the following three mechanisms: The first mechanism: the "molecular hook" effect of KH-590 modified filler. Hydrated nano-silica, modified and grafted with KH-590, is distributed in the shallow surface layer of the substrate. Its outwardly extending long-chain alkyl groups and trace amounts of free thiol groups that have not participated in the cross-linking reaction exhibit extremely high mobility at room temperature. When the tape is wrapped and compressed, these long-chain structures can penetrate the bonding interface and reversibly physically entangle with the opposite tape surface, forming pressure-sensitive adhesion points similar to "molecular hooks," providing the core self-adhesive peel force.
[0027] The second mechanism: confined surface wetting of DOP. Dioctyl phthalate (DOP) within the system is not freely free in the cross-linked network, but rather strongly adsorbed and confined by the high specific surface area of the nano-silica network. Under pressure bonding, a very small portion of DOP migrates to the surface, forming an extremely thin nano-scale wetting layer, effectively reducing surface energy and promoting physical adhesion at the interface. Because this migration is in a "filler adsorption-confined state," its thickness is strictly controlled at the nanoscale, preventing macroscopic exudation. Rigorous accelerated aging tests at 70℃ for 7 days verified that the product surface remained dry, without any oil stains or stickiness, perfectly balancing initial tackiness and surface cleanliness.
[0028] The third mechanism: compliant entanglement of surface vinyl segments. Methyl vinyl silicone rubber (MVQ) molecular chains inherently possess extremely low glass transition temperatures and high flexibility. Under conditions such as secondary vulcanization, a deep cross-linked network forms within the substrate to ensure mechanical strength, while the outermost layer of the substrate experiences thermal boundary effects, resulting in a microscopic cross-linking density gradient (i.e., relatively fewer cross-linking points in the surface micro-regions). This allows the vinyl side chains and main chain segments in the surface portion to maintain extremely high segment mobility similar to unvulcanized silicone rubber, enabling rapid molecular-level entanglement with the contact surface during winding and bonding.
[0029] Among the three mechanisms mentioned above, "molecular hooks" provide strong anchoring, "restricted wetting" increases the interfacial contact area, and "chain segment entanglement" provides adaptive adhesion. The synergy of these three mechanisms enables the product of this invention to not only have the initial peel strength required for use, but also achieve long-term storage stability far exceeding that of traditional tackifying systems, without the introduction of any external tackifiers. Example
[0030] This embodiment provides a composite insulating and sealing rubber tape, the rubber tape comprising a substrate layer and a composite reinforcing layer stacked sequentially, such as... Figure 1 and Figure 2 As shown; the nano-zirconia and carbon fiber in the composite reinforcement layer are partially pressed into and embedded in the shallow surface layer of the substrate layer during the hot-pressing composite stage, forming an embedded composite structure with the substrate layer. Formula composition (parts by weight): Substrate layer: 50 parts methyl vinyl silicone rubber, 25 parts hydrogenated nitrile rubber, 20 parts KH-590 modified composite filler, 3 parts vulcanizing agent, 2 parts antioxidant, and 4 parts softener. Composite reinforcement layer: 5 parts nano-zirconia and 3 parts carbon fiber.
[0031] Preparation process parameters: (1) Modification of composite filler: Add 1% by mass of silane coupling agent KH-590 to the composite filler; temperature 85℃, rotation speed 400r / min, time 45min; (2) Blending of substrates: temperature 125℃, rotation speed 70r / min, time 18min; (3) Component mixing: First stage temperature 115℃, rotation speed 60r / min, time 25min; second stage temperature 85℃, time 12min; (4) Reinforcing layer composite: temperature 145℃, pressure 6MPa, time 12min; (5) Primary vulcanization: temperature 160℃, pressure 11MPa, time 18min; (6) Secondary vulcanization: temperature 180℃, time 5h.
[0032] Detection methods and results: (1) Self-adhesion test: According to GB / T 2792-2014 standard, the 180° peel strength was tested and recorded as the initial peel strength; after the sample was stored in a room temperature and light-proof environment for 12 months, white needle-like substances were observed to precipitate, and the peel strength was tested again and recorded as the final peel strength. Self-adhesion retention rate = (final peel strength / initial peel strength) × 100%.
[0033] Test results: According to GB / T 2792-2014 standard, no white needle-like substances were precipitated after 12 months of storage, and the self-adhesive retention rate was ≥90%; Supplementary heat resistance precipitation test: The above samples were placed in a 70℃ oven for 7 consecutive days (simulating an extreme storage environment), and the surface condition was observed after removal. Test results: There was no oil stains or DOP (dimethylamine) or other plasticizer precipitation on the surface, and the samples remained dry with no decrease in self-adhesion. This proves the stability of the aforementioned "DOP-limited surface wetting" mechanism and eliminates the risk of interface contamination or debonding caused by macroscopic migration of plasticizers.
[0034] (2) Mechanical property test: Tested according to GB / T 528-2009 standard, using dumbbell-shaped specimens, tensile speed 500mm / min.
[0035] Test results: Elongation at break 480%, tensile strength 12.5 MPa; Interlayer bond strength test: Tested according to GB / T 2791-1995 standard, using the T-peel method.
[0036] Test results: The interlayer bond strength was 8.5 kN / m, and the interface failure was cohesive failure of the rubber matrix, indicating that the bond was strong. (4) Fatigue resistance test: A fatigue testing machine was used, and the reciprocating tensile conditions of 5 Hz frequency and 30% tensile strain were set for 10 hours. 6 After repeated deformation tests, the elastic recovery rate was measured after 10 minutes of static recovery.
[0037] Elastic recovery rate = [(Lmax - Lrest) / (Lmax - L0)] × 100%; where, L0: the original gauge length of the specimen; Lmax: The maximum length the specimen stretches during fatigue testing (i.e., the gauge length at maximum elongation). Lrest: Complete the specified number of times (e.g., 10) 6 The residual gauge length (Lrest) is measured after the reciprocating deformation test (after the load is removed and the rubber is left to stand for a specified time (usually 1-10 minutes). (Note: Because the rubber undergoes irreversible plastic deformation, the residual gauge length Lrest is numerically greater than the original gauge length L0; in the formula, "Lmax - Lrest" represents the recoverable elastic deformation and "Lmax - L0" represents the total deformation).
[0038] Test results: Elastic recovery rate 96%; (5) Wear resistance test: The wear amount is tested under the condition of a 40m stroke after pre-grinding by the rotating roller abrasion test method specified in GB / T 9867-2008 standard. The grinding wheel acts on the surface of the sample.
[0039] Test results: Wear amount 0.06g; (6) Aging test: The hot air accelerated aging test was carried out according to GB / T 3512-2014 standard, with a temperature of 150℃ and a time of 2000 hours; after aging, the tensile strength was tested according to GB / T 528, and the tensile strength decay was calculated.
[0040] Tensile strength attenuation rate = [(σ0-σ1) / σ0]×100%; where σ0: initial tensile strength before aging test; σ1: Tensile strength after aging test (2000 hours / 150℃).
[0041] Test results: Tensile strength decreased by 5%; (7) Insulation performance test: The volume resistivity is tested according to GB / T 1410-2006 standard. The sample is placed in a high and low temperature test chamber and tested after equilibration at three temperature points of -50℃, 25℃ and 150℃ for 1 hour respectively.
[0042] Insulation resistance attenuation rate = [(R ref -R min ) / R ref ]×100%; where R ref Insulation resistance value under reference conditions (usually referring to the initial value at room temperature of 25°C, or the maximum value within the test range).
[0043] R minThe minimum insulation resistance measured within the test temperature range (-50℃ to 150℃) (usually occurs at a high temperature of 150℃, because high temperature accelerates the movement of charge carriers and reduces insulation resistance).
[0044] Test results: Within the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹¹Ω·m and the attenuation rate is <10%.
[0045] Furthermore, regarding the insulation performance: Although conductive carbon fibers are introduced into the composite reinforcement layer, because the carbon fibers are uniformly dispersed and completely covered by the rubber matrix, and are distributed in a chopped pattern, a continuous conductive path is not formed. Surface insulation resistance testing shows that the surface resistivity of the product of this invention remains above 10¹¹ Ω·m, fully meeting the insulation protection requirements of high-voltage electrical equipment and eliminating the potential short-circuit risk posed by the carbon fibers. Example
[0046] This embodiment provides a composite insulating and sealing rubber tape, which includes a substrate layer and a composite reinforcing layer stacked in sequence; the nano-zirconia and carbon fiber in the composite reinforcing layer are partially pressed into and embedded in the shallow surface of the substrate layer during the hot-pressing composite stage, forming an embedded composite structure with the substrate layer. Formula composition (parts by weight): Substrate layer: 40 parts methyl vinyl silicone rubber, 20 parts hydrogenated nitrile rubber, 15 parts KH-590 modified composite filler, 2 parts vulcanizing agent, 1 part antioxidant, and 3 parts softener. Composite reinforcement layer: 3 parts nano-zirconia, 2 parts carbon fiber. The raw material grades and manufacturers are the same as in Example 1.
[0047] Preparation process parameters: (1) Modification of composite filler: Add 0.5% by mass of silane coupling agent KH-590 to the composite filler; temperature 80℃, rotation speed 300r / min, time 30min; (2) Blending of substrates: temperature 120℃, rotation speed 60r / min, time 15min; (3) Component mixing: First stage temperature 110℃, rotation speed 50r / min, time 20min; second stage temperature 80℃, time 10min; (4) Reinforcing layer composite: temperature 140℃, pressure 5MPa, time 10min; (5) Primary vulcanization: temperature 157℃, pressure 10MPa, time 15min; (6) Secondary vulcanization: temperature 178℃, time 4h.
[0048] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was ≥88%; (2) Mechanical property test: Elongation at break 510%, tensile strength 11.2 MPa; (3) Interlayer bond strength test: interlayer bond strength 8.0 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 95%. (5) Abrasion resistance test: abrasion amount 0.08g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 6%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹²Ω·m and the attenuation rate is <10%. Example
[0049] This embodiment provides a composite insulating and sealing rubber tape, which includes a substrate layer and a composite reinforcing layer stacked in sequence; the nano-zirconia and carbon fiber in the composite reinforcing layer are partially pressed into and embedded in the shallow surface of the substrate layer during the hot-pressing composite stage, forming an embedded composite structure with the substrate layer. Formula composition (parts by weight): Substrate layer: 60 parts methyl vinyl silicone rubber, 30 parts hydrogenated nitrile rubber, 25 parts KH-590 modified composite filler, 4 parts vulcanizing agent, 3 parts antioxidant, and 6 parts softener. Composite reinforcement layer: 8 parts nano-zirconia, 5 parts carbon fiber. The raw material grades and manufacturers are the same as in Example 1.
[0050] Preparation process parameters: (1) Modification of composite filler: Add 1.5% by mass of silane coupling agent KH-590 to the composite filler; temperature 90℃, rotation speed 500r / min, time 60min; (2) Blending of substrates: temperature 130℃, rotation speed 80r / min, time 20min; (3) Component mixing: First stage temperature 120℃, rotation speed 70r / min, time 30min; second stage temperature 90℃, time 15min; (4) Reinforcing layer composite: temperature 150℃, pressure 8MPa, time 15min; (5) Primary vulcanization: temperature 163℃, pressure 12MPa, time 20min; (6) Secondary vulcanization: temperature 182℃, time 6h.
[0051] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was ≥92%; (2) Mechanical property test: Elongation at break 450%, tensile strength 13.8 MPa; (3) Interlayer bond strength test: interlayer bond strength 9.2 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 97%. (5) Abrasion resistance test: abrasion amount 0.05g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 4%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹³Ω·m and the attenuation rate is <6%.
[0052] Comparative Example 1 (Primary Technology Comparison) Formulation composition: Based on EPDM rubber (80 parts), with the addition of 5 parts boron-based tackifier, 10 parts single flame retardant, and 5 parts other additives (including 2 parts accelerator, 2 parts crosslinking agent, and 1 part antioxidant). Specifically, the boron-based tackifier (trade name cobalt borylate) was purchased from Meyors Chemical INC Limited; the single flame retardant was aluminum hydroxide (hydrated alumina), purchased from Hefei Zhongke Flame Retardant New Materials Co., Ltd.; the accelerator (Actmix MBT-80GE / C) was purchased from Ningbo Aikem New Materials Co., Ltd.; the crosslinking agent was insoluble sulfur IS 8010 (chemical name polysulfide), purchased from Shangshun Chemical; and the antioxidant was rubber antioxidant 4010NA (IPPD), chemical name N-isopropyl-N'-phenyl-p-phenylenediamine, purchased from Weifang Zhong'an Rubber Materials Co., Ltd.
[0053] Preparation process: The conventional mixing and vulcanization process is adopted. The first vulcanization temperature is 155℃ and the time is 20min. There is no secondary vulcanization or reinforcing layer composite step.
[0054] Detection method (same as Example 1) and results: (1) Self-adhesion test: After 8 months of storage, white needle-like substances were precipitated, and the self-adhesion retention rate was only 65%; (2) Mechanical property test: Elongation at break 320%, tensile strength 9.8 MPa; (3) Interlayer adhesion strength test: The product is a homogeneous single-layer structure with no interlayer interface, so this test is not applicable; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 85%. (5) Abrasion resistance test: abrasion amount 0.15g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 18%; (7) Insulation performance test: Insulation resistance ≥10¹ within the temperature range of -50℃ to 150℃. 0 Ω·m, attenuation rate 25%.
[0055] Comparative Example 2 This comparative example is similar to Example 1, except that the "S4 reinforcement layer composite" step is omitted. Nano-zirconia and carbon fibers are directly added to a mixer and blended together with the substrate layer components to prepare a single-layer homogeneous rubber belt.
[0056] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 89%; (2) Mechanical property test: Elongation at break 380%, tensile strength 10.2 MPa; (3) Interlayer bond strength test: There is no obvious interlayer structure, and there is no reference value for bond strength; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 88%. (5) Abrasion resistance test: abrasion amount 0.12g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 12%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹¹Ω・m and the attenuation rate is 18%.
[0057] Comparative Example 3 This comparative example is similar to Example 1, except that the composite filler was not modified by silane coupling agent KH-590 and was directly added to the substrate in the original proportion.
[0058] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 85%; (2) Mechanical property test: Elongation at break 350%, tensile strength 9.5MPa; (3) Interlayer bond strength test: interlayer bond strength 6.8 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 90%. (5) Abrasion resistance test: abrasion amount 0.11g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 14%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹¹Ω・m and the attenuation rate is 15%.
[0059] Comparative Example 4 This comparative example is similar to Example 1, except that only nano-zirconia (5 parts) is added to the composite reinforcing layer, and no carbon fiber is added.
[0060] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 90%; (2) Mechanical property test: Elongation at break 400%, tensile strength 10.8 MPa; (3) Interlayer bond strength test: interlayer bond strength 7.2 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 92%. (5) Abrasion resistance test: abrasion amount 0.10g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 10%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹²Ω・m and the attenuation rate is 12%.
[0061] Comparative Example 5 This comparative example is similar to Example 1, except that only 3 parts of carbon fiber are added to the composite reinforcement layer, and 5 parts of nano-zirconia are not added.
[0062] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 89%; (2) Mechanical property test: Elongation at break 410%, tensile strength 11.0 MPa; (3) Interlayer bond strength test: interlayer bond strength 6.9 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 89%. (5) Abrasion resistance test: abrasion amount 0.13g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 11%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹²Ω・m and the attenuation rate is 12%.
[0063] Comparative Example 6 This comparative example is similar to Example 1, except that the reinforcing layer is laminated using a room temperature bonding process (temperature 25°C, pressure 5MPa, time 30min) instead of a hot-pressing bonding process.
[0064] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 90%; (2) Mechanical property test: Elongation at break 420%, tensile strength 11.5MPa; (3) Interlayer bond strength test: interlayer bond strength 5.8kN / m (easily delaminated); (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 93%. (5) Abrasion resistance test: abrasion amount 0.09g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 8%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹²Ω・m and the attenuation rate is 10%.
[0065] Comparative Example 7 This comparative example is similar to Example 1, except that hydrogenated nitrile rubber is removed from the substrate layer, and only 75 parts of methyl vinyl silicone rubber are used (original 50 parts + 25 parts added to replace 25 parts of hydrogenated nitrile rubber). The amount of other components (composite filler, vulcanizing agent, etc.) added is the same as in Example 1. The composite reinforcing layer is the same as in Example 1.
[0066] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 83%; (2) Mechanical property test: Elongation at break 350%, tensile strength 8.5MPa; (3) Interlayer bond strength test: interlayer bond strength 7.0 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 88%. (5) Abrasion resistance test: abrasion amount 0.13g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 16%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹¹Ω・m and the attenuation rate is 15%.
[0067] Comparative Example 8 This comparative example is similar to Example 1, except that the weight ratio of flame retardant component to reinforcing component in the composite filler is 1:1 (originally 2.5:1), and the total amount added remains unchanged.
[0068] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 88%; (2) Mechanical property test: Elongation at break 380%, tensile strength 11.8 MPa; (3) Interlayer bond strength test: interlayer bond strength 7.5 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 91%. (5) Abrasion resistance test: abrasion amount 0.07g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 9%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹²Ω・m and the attenuation rate is 10%.
[0069] Comparative Example 9 This comparative example is similar to Example 1, except that the weight ratio of flame retardant component to reinforcing component in the composite filler is 4:1 (originally 2.5:1), and the total amount added remains unchanged.
[0070] Detection method (same as Example 1) and results: (1) Self-adhesion test: No white needle-like substances were precipitated after 12 months of storage, and the self-adhesion retention rate was 85%; (2) Mechanical property test: Elongation at break 390%, tensile strength 10.2 MPa; (3) Interlayer bond strength test: interlayer bond strength 6.5 kN / m; (4) Fatigue resistance test: After 10 6 After repeated deformation tests, the elastic recovery rate was 90%. (5) Abrasion resistance test: abrasion amount 0.10g; (6) Aging test: After 2000 hours of hot air aging (150℃), the tensile strength decreased by 13%; (7) Insulation performance test: In the temperature range of -50℃ to 150℃, the insulation resistance is ≥10¹¹Ω・m and the attenuation rate is 14%.
[0071] Table 1 shows the statistical results of some tests on the products obtained in Examples 1-3 and Comparative Examples 1-9: Table 1
[0072] Note: - indicates not applicable. Five standard samples were prepared for each of the above performance tests, and the test results were taken as the average value, with standard deviations within ±10%.
[0073] The above results show that the composite insulating and sealing rubber tapes prepared in Examples 1-3 of the present invention are significantly superior to the comparative examples and existing technology products in terms of self-adhesive stability, mechanical properties, interlayer bonding strength, fatigue resistance, wear resistance, aging stability and insulation performance.
[0074] The embodiments described above are merely illustrative of specific implementations of the present invention, and while the descriptions are detailed, they should not be construed as limiting the scope of protection of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention.
Claims
1. A composite insulating and sealing rubber tape, characterized in that, The rubber belt includes a substrate layer and a composite reinforcement layer stacked sequentially. The nano-zirconia and carbon fiber in the composite reinforcement layer are partially pressed into and embedded in the shallow surface layer of the substrate layer during the hot-pressing composite stage, forming an embedded composite structure with the substrate layer. The substrate layer, by weight, is composed of the following components: 40-60 parts of methyl vinyl silicone rubber, 20-30 parts of hydrogenated nitrile rubber, 15-25 parts of composite filler modified with silane coupling agent KH-590, 2-4 parts of vulcanizing agent, 1-3 parts of antioxidant, and 3-6 parts of softener; wherein the composite filler includes a flame retardant component and a reinforcing component, and the weight ratio of the flame retardant component to the reinforcing component is 2:1 to 3:1; In the composite reinforcing layer, the amount of nano-zirconia added is 3-8 parts, and the amount of carbon fiber added is 2-5 parts.
2. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The vulcanizing agent is dicumyl peroxide.
3. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The antioxidant is antioxidant RD.
4. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The softener is dioctyl phthalate.
5. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The purity of the silane coupling agent KH-590 is above 98%.
6. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The flame retardant component is a halogen-free flame retardant, and the reinforcing component is hydrated nano-silica.
7. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The purity of the nano-zirconia is 99.9%.
8. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The carbon fiber is a short-cut carbon fiber with a length of 3 mm.
9. The composite insulating and sealing rubber tape according to claim 1, characterized in that, The composite reinforcement layer is prepared by mixing nano-zirconia and carbon fiber and then laying it on the surface of the substrate layer, and hot-pressing it at 140-150℃ and 5-8MPa for 10-15 minutes. After hot-pressing, the surface of the uncured substrate layer is deformed, causing the nano-zirconia and carbon fiber to partially embed into the shallow surface of the substrate layer. After curing and shaping, the inlaid composite structure is formed.
10. A manufacturing process for the composite insulating and sealing rubber tape according to any one of claims 1-9, characterized in that, Includes the following steps: S1. Modification of composite filler: Add the composite filler to a high-speed mixer, heat to 80-90℃, add 0.5-1.5% by weight of silane coupling agent KH-590, stir at 300-500 r / min for 30-60 min, and cool to room temperature after modification for later use. S2. Matrix material blending: Methyl vinyl silicone rubber and hydrogenated nitrile rubber are added to an internal mixer in proportion and mixed for 15-20 minutes at a temperature of 120-130℃ and a speed of 60-80 r / min to obtain a blended matrix material; S3. Component mixing: Add the S1 modified composite filler, antioxidant, and softener to the internal mixer in proportion, and continue mixing for 20-30 minutes at a temperature of 110-120℃ and a speed of 50-70r / min. Then add the vulcanizing agent, cool down to 80-90℃, stir for 10-15 minutes, and mix evenly to obtain the rubber compound. S4. Reinforcing layer composite: The rubber compound obtained in S3 is fed into a two-roll mill and calendered into a base layer with a thickness of 2-3 mm. Then, nano-zirconia and carbon fiber are mixed evenly in proportion and laid on the surface of the base layer. The composite is hot-pressed for 10-15 min at a temperature of 140-150℃ and a pressure of 5-8 MPa. S5. Vulcanization treatment: (1) First vulcanization: The semi-finished product after S4 composite is sent into the vulcanizing machine at a temperature of 160±3℃, a pressure of 10-12MPa, and a vulcanization time of 15-20min; (2) Secondary vulcanization: The product after primary vulcanization is sent into an oven at a temperature of 180±2℃ for 4-6 hours. S6. Post-processing: After vulcanization, cool to room temperature, then cut and trim to obtain the finished composite insulating and sealing rubber tape.