High-hardness easy-to-cut silicone rubber material as well as preparation method and application thereof

Abstract

The invention provides a high-hardness easy-to-cut silicone rubber material as well as a preparation method and application thereof. The high-hardness easy-to-cut silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 25-40 parts of fumed silica, 1.5-3 parts of hydroxyl silicone oil, 0.8-1.2 parts of a cross-linking agent, 0.05-0.1 part of a platinum catalyst and 1-2 parts of a heat-resistant stabilizer. Through screening and synergistic compounding of specific components in the silicone rubber material, synergistic optimization of shore hardness and elongation at break of the silicone rubber material is realized, and the silicone rubber material is ensured to be free of cracks after being aged at 180 DEG C for 3000 hours and still has an excellent elongation at break retention rate after being aged.

Description

Technical Field

[0001] This invention belongs to the field of rubber material technology, and relates to a high-hardness, easily cut silicone rubber material, its preparation method, and its application. Background Technology

[0002] my country's new energy vehicle industry is currently in a phase of rapid development, with its scale continuously expanding. This is accelerating the upgrading of production from manual to automated equipment, and major wire harness companies are introducing intelligent production lines to improve manufacturing efficiency. This transformation process has spurred new technological demands. In particular, the automation requirements for key wire harness manufacturing processes (such as high-precision cutting, stripping, and crimping) pose unprecedentedly higher and more specific technical challenges to the performance of silicone rubber insulation materials (such as hardness, elongation, and cutability) and the design and materials of cable shielding layers (such as anti-adhesion and easy peeling).

[0003] However, in the actual application of automated cutting processes, cables using traditional silicone rubber insulation materials and conventional aluminum foil shielding structures have exposed a series of serious problems, mainly including: wire insulation residue, braiding layer damage, and difficulty in peeling aluminum foil, which seriously restrict production efficiency, yield rate and production continuity. After in-depth analysis and multiple equipment matching verifications, the following obvious defects were found: (1) Insufficient hardness of insulation material: The hardness of current silicone rubber is generally ≤66A, and the insulation layer is easily sheared and worn by the metal braiding layer, producing glue debris that gets caught in the blade, resulting in glue sticking to the blade, increased frequency of machine shutdown for cleaning, and potential short circuit hazards. (2) Excessive elongation: The current material's elongation at break is generally >600%, resulting in rubber residue during cutting and a decrease in yield rate. (3) Aluminum foil residue during automated cutting: This requires manual peeling, which disrupts production continuity.

[0004] In summary, existing technologies have not yet solved the problems of synergistic optimization of material hardness and elongation, as well as aluminum foil residue. Therefore, it is urgent to develop a new silicone rubber formulation and optimize the cable structure to promote the intelligent upgrading of the new energy vehicle industry. Summary of the Invention

[0005] The purpose of this invention is to provide a high-hardness, easily cut silicone rubber material, its preparation method, and its application. By screening and synergistically compounding specific components in the silicone rubber material, the Shore hardness and elongation at break of the silicone rubber material are synergistically optimized, and it is ensured that the material does not crack after aging at 180°C for 3000 hours, and still has an excellent elongation at break retention rate after aging.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a high-hardness, easily cut silicone rubber material, wherein the high-hardness, easily cut silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 25-40 parts of fumed silica, 1.5-3 parts of hydroxyl silicone oil, 0.8-1.2 parts of crosslinking agent, 0.05-0.1 parts of platinum catalyst, and 1-2 parts of heat-resistant stabilizer.

[0008] The silicone rubber material provided by this invention comprises a combination of methyl vinyl silicone rubber, fumed silica, hydroxyl silicone oil, crosslinking agent, platinum catalyst and heat-resistant stabilizer. Through the screening and synergistic compounding of specific components, the Shore hardness and elongation at break of the silicone rubber material are synergistically optimized, and it is ensured that the material does not crack after aging at 180°C for 3000 hours, and still has excellent elongation at break retention rate after aging.

[0009] It should be noted that by using a specific weight ratio of fumed silica and hydroxyl silicone oil in combination, the Shore A hardness and elongation at break are synergistically optimized, effectively solving the technical bottlenecks of rubber residue and braid layer wear in the automated cutting of high-voltage cables for new energy vehicles.

[0010] It should also be noted that by using a specific weight ratio of platinum catalyst and heat-resistant stabilizer, the molecular chain reconstruction of the cut surface can be promoted, ensuring that the silicone rubber material does not crack after aging at 180℃ for 3000 hours, and still has excellent elongation at break retention rate after aging, which significantly improves cutting efficiency, greatly reduces production costs, and promotes the intelligent upgrading of the new energy vehicle wiring harness industry.

[0011] In this invention, the weight percentage of fumed silica in the high-hardness, easily cut silicone rubber material is 25-40 parts, for example, 26 parts, 28 parts, 30 parts, 32 parts, 34 parts, 35 parts, 36 parts, or 38 parts; the weight percentage of hydroxyl silicone oil in the high-hardness, easily cut silicone rubber material is 1.5-3 parts, for example, 1.6 parts, 1.8 parts, 2 parts, 2.2 parts, 2.4 parts, 2.5 parts, 2.6 parts, or 2.8 parts; and the weight percentage of crosslinking agent in the high-hardness, easily cut silicone rubber material is 0.8-1.2 parts, for example, 0.85 parts, 0. The platinum catalyst in the high-hardness, easily cut silicone rubber material is 0.05-0.1 parts by weight, for example, 0.06, 0.065, 0.07, 0.075, 0.08, 0.085, or 0.09 parts by weight; the heat stabilizer in the high-hardness, easily cut silicone rubber material is 1-2 parts by weight, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, or 1.9 parts by weight.

[0012] Preferably, the vinyl content in the methyl vinyl silicone rubber is 0.12 mol%-0.18 mol%, for example, it can be 0.13 mol%, 0.14 mol%, 0.15 mol%, 0.16 mol% or 0.17 mol%, etc.

[0013] In this invention, the vinyl content in methyl vinyl silicone rubber refers to the molar percentage of vinyl groups in the methyl vinyl silicone rubber. In the basic structure of methyl vinyl silicone rubber, the methyl group is the main component, and the vinyl group is the reactive functional group used for crosslinking. Therefore, the vinyl content range needs to be controlled to ensure the crosslinking effect.

[0014] It should be noted that if the vinyl content in methyl vinyl silicone rubber is too low, the crosslinking density will be insufficient due to the lack of functional groups used for crosslinking, resulting in a significant decrease in the hardness and mechanical strength of the silicone rubber material. If the vinyl content in methyl vinyl silicone rubber is too high, the crosslinking points will be too dense, restricting the movement of molecular chain segments, resulting in a decrease in the elasticity of the silicone rubber material, an increase in brittleness, and an excessively low elongation at break.

[0015] Preferably, the specific surface area of ​​the fumed silica is 150 m². 2 / g-200m 2 / g, for example, could be 155m 2 / g、160m 2 / g、165m 2 / g、170m 2 / g、175m 2 / g、180m 2 / g、185m 2 / g、190m 2 / g or 195m 2 / g etc.

[0016] It should be noted that by controlling the specific surface area of ​​fumed silica within a specific range, the reinforcing properties of silicone rubber can be significantly enhanced while avoiding the deterioration of processing performance, thus achieving a win-win situation for both reinforcing effect and processing performance.

[0017] Preferably, the crosslinking agent comprises dicumyl peroxide.

[0018] Preferably, the heat stabilizer comprises cerium dioxide.

[0019] Preferably, the Shore hardness of the high-hardness, easily cut silicone rubber material is 66A-72A, for example, it can be 66.5A, 67A, 67.5A, 68A, 68.5A, 69A, 69.5A, 70A, 70.5A, 71A or 71.5A, etc.

[0020] Preferably, the elongation at break of the high-hardness, easily cut silicone rubber material is 400%-450%, for example, it can be 405%, 410%, 415%, 420%, 425%, 430%, 435%, 440% or 445%, etc.

[0021] Preferably, the high-hardness, easily cut silicone rubber material retains ≥150% of its elongation at break after aging at 180°C for 3000 hours, for example, 155%, 160%, 165%, 170%, 175%, 180%, 185%, 190%, or 200%.

[0022] In a second aspect, the present invention provides a method for preparing a high-hardness, easily cut silicone rubber material as described in the first aspect, the method comprising:

[0023] The methyl vinyl silicone rubber, fumed silica and hydroxyl silicone oil are first mixed, then a heat stabilizer is added after heating for a second mixing, and then a crosslinking agent and platinum catalyst are added after cooling for a third mixing to obtain the rubber compound.

[0024] The preparation method provided by this invention is simple to operate, and the prepared silicone rubber material has excellent hardness, tensile properties and processing properties. It also has the advantages of high work efficiency and suitability for mass production.

[0025] Preferably, the temperature of the first mixing is 48℃-52℃, for example, it can be 48.5℃, 49℃, 49.5℃, 50℃, 50.5℃, 51℃ or 51.5℃, etc.

[0026] Preferably, the first mixing time is 10 min to 20 min, for example, it can be 11 min, 12 min, 13 min, 14 min, 15 min, 16 min, 17 min, 18 min or 19 min, etc.

[0027] Preferably, the temperature of the second mixing is 58℃-62℃, for example, it can be 58.5℃, 59℃, 59.5℃, 60℃, 60.5℃, 61℃ or 61.5℃, etc.

[0028] Preferably, the second mixing time is 8-12 minutes, for example, it can be 8.5 minutes, 9 minutes, 9.5 minutes, 10 minutes, 10.5 minutes, 11 minutes or 11.5 minutes, etc.

[0029] Preferably, the temperature of the third mixing is 38℃-42℃, for example, it can be 38.5℃, 39℃, 39.5℃, 40℃, 40.5℃, 41℃ or 41.5℃, etc.

[0030] It should be noted that if the temperature of the third mixing is too high, or if the first, second and third mixing are all carried out at the same temperature, the crosslinking agent and platinum catalyst will decompose or react too early during the mixing stage, resulting in insufficient effective components during formal vulcanization. This will lead to insufficient vulcanization of the obtained silicone rubber material, substandard hardness and mechanical properties, and deterioration of aging resistance.

[0031] Preferably, the third mixing time is 3-8 minutes, for example, it can be 3.5 minutes, 4 minutes, 4.5 minutes, 5 minutes, 5.5 minutes, 6 minutes, 6.5 minutes, 7 minutes or 7.5 minutes, etc.

[0032] As an example, the mixed rubber compound can be further extruded and then vulcanized for corresponding performance tests.

[0033] Thirdly, the present invention provides a silicone rubber cable, the silicone rubber cable including a center conductor, and a silicone rubber insulation layer, a braided layer, an easy-tear aluminum foil layer and a silicone rubber sheath layer are sequentially disposed outside the center conductor;

[0034] The materials of the silicone rubber insulation layer and the silicone rubber sheath both include the high-hardness, easily cut silicone rubber material described in the first aspect.

[0035] The silicone rubber cable provided by this invention uses the aforementioned high-hardness, easily cut silicone rubber material for both the silicone rubber insulation layer and the silicone rubber sheath, effectively solving the problems of rubber residue and braid damage in automated production. Furthermore, the silicone rubber cable products all meet the LV 216 standard requirements and can be adapted to mainstream automated production lines, significantly improving cutting speed and greatly reducing production costs.

[0036] Preferably, the easy-tear aluminum foil layer comprises an aluminum layer, an adhesive layer, and a PET layer stacked together.

[0037] Preferably, the thickness of the aluminum layer is 0.012mm-0.018mm, for example, it can be 0.013mm, 0.014mm, 0.015mm, 0.016mm or 0.017mm, etc.; the elongation at break is 20%-35%, for example, it can be 22%, 24%, 25%, 26%, 28%, 30%, 32% or 34%, etc.

[0038] Preferably, the peel strength of the adhesive layer is ≥2.6 N / cm, for example, it can be 2.7 N / cm, 2.8 N / cm, 2.9 N / cm, 3 N / cm or 3.2 N / cm, etc.; the heat sealing strength is ≥8.72 N / cm, for example, it can be 8.75 N / cm, 8.76 N / cm, 8.78 N / cm, 8.8 N / cm or 8.9 N / cm, etc.

[0039] Preferably, the thickness of the PET layer is 0.005mm-0.007mm, for example, it can be 0.0052mm, 0.0055mm, 0.0056mm, 0.0058mm, 0.006mm, 0.0062mm, 0.0065mm, 0.0066mm or 0.0068mm, etc.; the elongation at break is 15%-30%, for example, it can be 16%, 18%, 20%, 22%, 24%, 25%, 26% or 28%, etc.

[0040] It should be noted that by reducing the thickness of the PET layer in the easy-tear aluminum foil layer, and by optimizing the elongation at break of the aluminum layer to match that of the PET layer, deformation coordination during cutting is ensured, thus solving the problem of cutting residue in the easy-tear aluminum foil layer during automated production.

[0041] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) The silicone rubber material provided by this invention comprises a combination of methyl vinyl silicone rubber, fumed silica, hydroxyl silicone oil, crosslinking agent, platinum catalyst, and heat-resistant stabilizer. Through the screening and synergistic compounding of specific components, the Shore hardness and elongation at break of the silicone rubber material are synergistically optimized, and it is ensured that the material does not crack after aging at 180℃ for 3000h, and still has excellent elongation at break retention rate after aging. Specifically, the prepared silicone rubber material has a Shore hardness ≥66A, an elongation at break of 400%-450%, no cracks after aging at 180℃ for 3000h, and an elongation at break retention rate ≥150%, and an elongation at break retention rate ≥100% after aging at 200℃ for 3000h.

[0044] (2) The method for preparing silicone rubber material provided by the present invention is simple to operate, and the prepared silicone rubber material has excellent hardness, tensile properties and processing properties, as well as advantages such as high working efficiency and suitability for mass production.

[0045] (3) The silicone rubber cable provided by the present invention uses the aforementioned high-hardness, easy-to-cut silicone rubber material for the silicone rubber insulation layer and silicone rubber sheath. Combined with reducing the thickness of the PET layer in the easy-tear aluminum foil layer and optimizing the matching of the breaking elongation of the aluminum layer and the PET layer, it effectively solves the problems of rubber residue and braid layer damage in automated production. Moreover, the silicone rubber cable products all meet the standard requirements of LV 216 and can be adapted to mainstream automated production lines, significantly improving the cutting speed and greatly reducing the production cost. Attached Figure Description

[0046] Figure 1 A schematic diagram of the cross-sectional structure of the silicone rubber cable provided for Application Example 1;

[0047] Among them, 1-center conductor, 2-silicone rubber insulation layer, 3-braided layer, 4-easy-tear aluminum foil layer, 5-silicone rubber sheath layer. Detailed Implementation

[0048] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0049] All materials used in the specific embodiments of this invention are commercially available or prepared using conventional methods in the prior art. All methods employed are conventional techniques in the field.

[0050] Example 1

[0051] This embodiment provides a high-hardness, easily cut silicone rubber material and its preparation method. The high-hardness, easily cut silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 28 parts of fumed silica, 1.8 parts of hydroxyl silicone oil, 0.9 parts of crosslinking agent, 0.05 parts of platinum catalyst, and 1.1 parts of heat-resistant stabilizer.

[0052] The methyl vinyl silicone rubber contains 0.12 mol% vinyl content; the fumed silica has a specific surface area of ​​200 m² / g. 2 / g; the crosslinking agent is dicumyl peroxide; the heat-resistant stabilizer is cerium dioxide.

[0053] The preparation method includes: mixing methyl vinyl silicone rubber, fumed silica and hydroxyl silicone oil at 48°C for 20 minutes, adding a heat-resistant stabilizer at 58°C for 12 minutes after heating, adding a crosslinking agent and a platinum catalyst at 38°C for 8 minutes after cooling, and obtaining the rubber compound.

[0054] Example 2

[0055] This embodiment provides a high-hardness, easily cut silicone rubber material and its preparation method. The high-hardness, easily cut silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 40 parts of fumed silica, 2.8 parts of hydroxyl silicone oil, 1.2 parts of crosslinking agent, 0.1 parts of platinum catalyst, and 2 parts of heat-resistant stabilizer.

[0056] The methyl vinyl silicone rubber contains 0.18 mol% vinyl content; the fumed silica has a specific surface area of ​​150 m² / g. 2 / g; the crosslinking agent is dicumyl peroxide; the heat-resistant stabilizer is cerium dioxide.

[0057] The preparation method includes: mixing methyl vinyl silicone rubber, fumed silica and hydroxyl silicone oil at 52°C for 10 minutes, adding a heat-resistant stabilizer at 62°C for 8 minutes, and adding a crosslinking agent and platinum catalyst at 42°C for 4 minutes after cooling down to obtain the rubber compound.

[0058] Example 3

[0059] This embodiment provides a high-hardness, easily cut silicone rubber material and its preparation method. The high-hardness, easily cut silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 30 parts of fumed silica, 2.2 parts of hydroxyl silicone oil, 1 part of crosslinking agent, 0.08 parts of platinum catalyst, and 1.5 parts of heat-resistant stabilizer.

[0060] The methyl vinyl silicone rubber contains 0.15 mol% vinyl content; the fumed silica has a specific surface area of ​​180 m². 2 / g; the crosslinking agent is dicumyl peroxide; the heat-resistant stabilizer is cerium dioxide.

[0061] The preparation method includes:

[0062] Methyl vinyl silicone rubber, fumed silica, and hydroxyl silicone oil were first mixed at 50°C for 15 minutes. After heating, a heat-resistant stabilizer was added and the mixture was second mixed at 60°C for 10 minutes. After cooling, a crosslinking agent and a platinum catalyst were added and the mixture was third mixed at 40°C for 5 minutes to obtain the rubber compound.

[0063] Comparative Example 1

[0064] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except that the amount of fumed silica used is 15 parts, all other conditions are the same as in Example 1.

[0065] Comparative Example 2

[0066] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except that the amount of fumed silica used is 50 parts, all other conditions are the same as in Example 1.

[0067] Comparative Example 3

[0068] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except that the amount of hydroxyl silicone oil used is 7 parts, all other conditions are the same as in Example 1.

[0069] Comparative Example 4

[0070] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except that the amount of the platinum catalyst is 0.5 parts, all other conditions are the same as in Example 1.

[0071] Comparative Example 5

[0072] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except for the absence of a platinum catalyst, all other conditions are the same as in Example 1.

[0073] Comparative Example 6

[0074] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method. Except that the amount of the heat-resistant stabilizer is 0.5 parts, all other conditions are the same as in Example 1.

[0075] Comparative Example 7

[0076] This comparative example provides a high-hardness, easily cut silicone rubber material and its preparation method, except that the amount of the heat-resistant stabilizer is 4 parts; all other conditions are the same as in Example 1.

[0077] The rubber compounds prepared in the above examples and comparative examples were extruded and vulcanized at 160°C. The relevant performance tests were then conducted, and the test results are shown in Table 1.

[0078] Performance testing

[0079] (1) Shore hardness: tested using a Shore A hardness tester;

[0080] (2) Elongation at break: The test was conducted using a tensile testing machine at a test speed of 250 mm / min and an initial gauge length of 20 mm.

[0081] (3) Anti-aging performance: Tested in accordance with GB / T3512-2004 standard.

[0082] Table 1

[0083]

[0084] As shown in Table 1:

[0085] The silicone rubber materials and their preparation methods provided in Examples 1-3 of this invention include a combination of methyl vinyl silicone rubber, fumed silica, hydroxyl silicone oil, crosslinking agent, platinum catalyst, and heat-resistant stabilizer. Through the screening and synergistic compounding of specific components, combined with an optimized preparation method, the Shore hardness and elongation at break of the silicone rubber material are synergistically optimized, ensuring that the material does not crack after aging at 180°C for 3000 hours and still has excellent elongation at break retention after aging. Specifically, the prepared silicone rubber material has a Shore hardness ≥66A, an elongation at break of 400%-450%, no cracks after aging at 180°C for 3000 hours, and an elongation at break retention rate ≥150%, and an elongation at break retention rate ≥100% after aging at 200°C for 3000 hours.

[0086] A comparison of Example 1 and Comparative Examples 1-2 shows that if the amount of fumed silica is too low, the reinforcing effect decreases, the resulting silicone rubber material has a low Shore hardness and insufficient mechanical strength, and is prone to rubber residue due to insufficient strength during automated cutting. If the amount of fumed silica is too high, although the reinforcing effect is improved and the Shore hardness is significantly increased, the processing performance of the silicone rubber material deteriorates, specifically manifested as excessively hard rubber compound, difficulty in mixing and dispersing, rough extrusion surface, and decreased material toughness.

[0087] A comparison of Example 1 and Comparative Example 3 shows that if the amount of hydroxyl silicone oil is too high, it will occupy too many interaction points between the filler and the rubber matrix as a processing aid, thus "diluting" the crosslinking density. This results in a significant reduction in the hardness and tensile strength of the silicone rubber material, and an excessively high elongation, returning it to the undesirable performance range of traditional materials.

[0088] A comparison of Example 1 and Comparative Examples 4-5 shows that if the amount of platinum catalyst is too high, the excessively high catalytic activity may cause local cross-linking to occur too quickly, destroying the uniformity of the cross-linking network. This results in a decrease in the toughness of the prepared silicone rubber material and increases costs without bringing additional performance benefits. If no platinum catalyst is added, the oxidative degradation and rearrangement reaction of the silicone rubber backbone at high temperatures cannot be effectively suppressed, leading to a sharp deterioration in the heat aging resistance of the prepared silicone rubber material. The elongation retention rate after high-temperature aging is far lower than the target value, and there is a risk of cracking.

[0089] A comparison of Example 1 and Comparative Examples 6-7 shows that if the amount of cerium oxide is too low, the long-term thermal stability and anti-aging properties of the prepared silicone rubber material cannot meet the 3000-hour aging requirement due to insufficient ability to capture free radicals at high temperatures and insufficient stabilization effect on polymer chains. If the amount of cerium oxide is too high, excessive filler may interfere with the integrity of the crosslinking network to a certain extent and introduce impurity points, resulting in a slight decrease in the mechanical properties (such as tensile strength and elongation) of the prepared silicone rubber material and a worse cost-effectiveness.

[0090] Application Example 1

[0091] This application example provides a silicone rubber cable, the cross-sectional structure of which is shown in the schematic diagram below. Figure 1 As shown, the dimensions of the silicone rubber cable are designed with reference to the LV 216-2 cable; the silicone rubber cable includes a center conductor, and the center conductor 1 is sequentially provided with a silicone rubber insulation layer 2, a braided layer 3, an easy-tear aluminum foil layer 4, and a silicone rubber sheath layer 5;

[0092] Wherein, the center conductor 1 is an annealed bare copper stranded conductor formed by regular stranding;

[0093] The material of the silicone rubber insulating layer 2 is the high-hardness, easily cut silicone rubber material obtained in Example 1;

[0094] The material of the braided layer 3 is tin-plated copper wire;

[0095] The easy-tear aluminum foil layer 4 includes an aluminum layer, an adhesive layer, and a PET layer stacked together; the aluminum layer is in contact with the braided layer 3; and the PET layer is in contact with the silicone rubber sheath layer 5.

[0096] The aluminum layer has a thickness of 0.015 mm and an elongation at break of 25%; the adhesive layer has a peel strength of 2.8 N / cm and a heat-sealing strength of 8.9 N / cm; the PET layer has a thickness of 0.006 ± 0.001 mm and an elongation at break of 20%.

[0097] The material of the silicone rubber sheath layer 5 is the high-hardness, easily cut silicone rubber material obtained in Example 1.

[0098] Application Example 2

[0099] This application example provides a silicone rubber cable, which is identical to Application Example 1 except that the thickness of the PET layer is 0.015 mm.

[0100] Application Example 3

[0101] This application example provides a silicone rubber cable, which is identical to Application Example 1 except that the elongation at break of the PET layer is 10%.

[0102] Application Example 4

[0103] This application example provides a silicone rubber cable, which is identical to Application Example 1 except that the elongation at break of the PET layer is 35%.

[0104] The silicone rubber cables prepared in the above application examples were subjected to automated cutting performance tests, and the test results are shown in Table 2.

[0105] Table 2

[0106]

[0107] As shown in Table 2:

[0108] The silicone rubber insulation layer and silicone rubber sheath layer are prepared using the silicone rubber material provided in Embodiment 1 of the present invention. Combined with the optimization of the easy-tear aluminum foil layer, the prepared silicone rubber cable has excellent deformation coordination during automated cutting and can avoid aluminum foil layer residue.

[0109] A comparison of Application Example 1 and Application Example 2 shows that if the PET layer is thicker, its rigidity and tear resistance are enhanced, making it less likely to break simultaneously with the sharp cutting blade at the moment of cutting, resulting in aluminum foil residue in the silicone rubber cable during automated cutting.

[0110] A comparison of Application Examples 1 and 3-4 shows that if the elongation at break of the PET layer is too low, it becomes brittle and will irregularly fracture or break before the aluminum layer during cutting, failing to form a neat cut surface. This causes the aluminum layer to be stretched and deformed due to the loss of effective support from the PET layer, and some aluminum foil will remain in the cut due to the premature breakage of the PET layer. If the elongation at break of the PET layer is too high, its excessive extensibility will cause it to undergo significant stretching deformation during cutting instead of being cut off. Similar to "rubber residue," the PET layer will be stretched along with the aluminum layer, hindering the complete penetration of the cutter. This also causes the aluminum foil-PET composite layer to be pulled out as a whole, resulting in residue.

[0111] The present invention has been illustrated with the above embodiments to illustrate its detailed structural features. However, the present invention is not limited to the above detailed structural features, that is, it does not mean that the present invention must rely on the above detailed structural features to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions for the components used in the present invention, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A high hardness, easy-to-cut silicone rubber material, characterized by, The high-hardness easy-cutting silicone rubber material comprises the following components in parts by weight: 100 parts of methyl vinyl silicone rubber, 25-40 parts of fumed white carbon black, 1.5-3 parts of hydroxyl silicone oil, 0.8-1.2 parts of crosslinking agent, 0.05-0.1 parts of platinum catalyst and 1-2 parts of heat-resistant stabilizer.

2. The high hardness, easy to cut silicone rubber material according to claim 1, characterized in that, The content of vinyl in the methyl vinyl silicone rubber is 0.12-0.18 mol %.

3. The high hardness, easy to cut silicone rubber material according to claim 1, wherein, The specific surface area of the fumed white carbon is 150 m 2 / g-200 m 2 / g.

4. The high hardness, easy to cut silicone rubber material according to claim 1, wherein, The crosslinking agent comprises dicumyl peroxide; Preferably, the heat-resistant stabilizer comprises cerium dioxide.

5. The high hardness, easy to cut silicone rubber material according to claim 1, wherein, The Shore hardness of the high-hardness easy-cutting silicone rubber material is 66A-72A. Preferably, the elongation at break of the high-hardness easy-cutting silicone rubber material is 400-450 %. Preferably, the retention rate of the elongation at break of the high-hardness easy-cutting silicone rubber material after aging at 180℃ for 3000h is ≥150 %.

6. A process for the preparation of a high hardness, easy to cut silicone rubber material as claimed in any one of claims 1 to 5, characterized in that, The preparation method comprises: The methyl vinyl silicone rubber, the fumed white carbon black and the hydroxyl silicone oil are first mixed, the heat-resistant stabilizer is added after heating and second mixed, the crosslinking agent and the platinum catalyst are added after cooling and third mixed to obtain a rubber compound.

7. The production method according to claim 6, wherein The temperature of the first mixing is 48-52℃; Preferably, the time of the first mixing is 10-20 min. Preferably, the temperature of the second mixing is 58-62℃; Preferably, the time of the second mixing is 8-12 min.

8. The preparation method according to claim 6, characterized in that, The temperature of the third mixing is 38-42℃; Preferably, the time of the third mixing is 3-8 min.

9. A silicone rubber cable, characterized by The silicone rubber cable comprises a center conductor, and the center conductor is sequentially provided with a silicone rubber insulation layer, a braided layer, an easy-to-tear aluminum foil layer and a silicone rubber sheath layer. The material of the silicone rubber insulation layer and the silicone rubber sheath both comprises the high-hardness easy-cutting silicone rubber material according to any one of claims 1-5.

10. A silicone rubber cable according to claim 9, characterised in that, The easy-to-tear aluminum foil layer comprises an aluminum layer, an adhesive layer and a PET layer which are stacked. Preferably, the thickness of the aluminum layer is 0.012-0.018 mm, and the elongation at break is 20-35 %. Preferably, the peeling strength of the adhesive layer is ≥2.6 N / cm, and the heat sealing strength is ≥8.72 N / cm. Preferably, the thickness of the PET layer is 0.005-0.007 mm, and the elongation at break is 15-30 %.

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