Weather-resistant flame-retardant silicone rubber material and method for preparing the same

Abstract

This application relates to the field of silicone materials, and more specifically, to a weather-resistant and flame-retardant silicone material and its preparation method. It is prepared from the following raw materials in weight percentages: 65-80% raw rubber, 5-10% hydrogen-containing silicone oil, 5-18% modifier, and the balance being processing aids; the modifier is prepared from silicone powder, PI powder, Teflon powder, and compatibilizer in a weight ratio of 1:(1-3):(3-5):(1-2). The modifier prepared from silicone powder, PI powder, Teflon powder, and compatibilizer possesses excellent flame-retardant properties, toughening and reinforcement, compatibility, and weather resistance. It can be thoroughly and uniformly mixed with raw rubber, and combined with hydrogen-containing silicone oil, further cross-linking the raw rubber and adjusting its softness. This results in cables made from the silicone material possessing both excellent mechanical and flame-retardant properties, while also exhibiting excellent resistance to harsh environments such as high temperature, strong ultraviolet radiation, and salt, further improving the durability and safety of charging pile cables.

Description

Technical Field

[0001] This application relates to the field of silicone materials, and more specifically, to a weather-resistant and flame-retardant silicone material and its preparation method. Background Technology

[0002] Silicone materials possess excellent flexibility and toughness, making them commonly used in the production of electrical wires and cables, electronics, and kitchenware. Taking silicone materials for charging piles as an example, in addition to improving flame retardancy, the characteristics of wires and cables in terms of winding, bending, and other aspects must be considered to reduce problems such as kinking and wrinkling, thereby improving the convenience and safety of charging. Furthermore, properties such as abrasion resistance, oil resistance, acid and alkali resistance, and tear resistance must be considered to ensure that the cable maintains stable performance in harsh environments and extends its service life.

[0003] Currently, to improve the flame retardant properties of silicone materials, a large amount of flame retardant is added, which reduces the mechanical properties and flexibility of the silicone material. Modified flame retardants are also used to reduce the impact on the mechanical properties and flexibility of silicone materials while achieving better flame retardant performance. However, silicone materials are still susceptible to aging due to environmental factors during long-term use. Environmental factors such as high temperature, ultraviolet radiation, and humidity accelerate the aging process of silicone materials, leading to a decline in their mechanical and flame retardant properties, thereby affecting the service life and safety of wires and cables.

[0004] Especially when used in charging pile cables in hot coastal areas, the sea breeze carries salt, and over time, salt easily adheres to the surface of the cables, making them susceptible to salt corrosion. Since charging pile cables are often exposed, and the coastal areas have strong ultraviolet radiation and high temperatures, silicone rubber cables are prone to cracking and damage, reducing their durability and safety. Summary of the Invention

[0005] In order to obtain silicone materials with better mechanical and flame-retardant properties, and at the same time improve their resistance to high temperature, strong ultraviolet radiation and salt environment, this application provides a weather-resistant and flame-retardant silicone material and its preparation method.

[0006] In a first aspect, this application provides a weather-resistant and flame-retardant silicone material, made from the following raw materials by weight percentage: 65-80% raw rubber.

[0007] Hydrogen-containing silicone oil 5-10%

[0008] Modifier 5-18%

[0009] The remainder is processing aids;

[0010] The modifier is prepared by mixing silicone powder, PI powder, Teflon powder and compatibilizer in a weight ratio of 1:(1-3):(3-5):(1-2).

[0011] In the above scheme, silicone powder, PI powder, and Teflon powder all play a good role in flame retardancy, reinforcement and toughening, salt corrosion resistance, heat resistance, and UV aging resistance. When silicone powder, PI powder, and Teflon powder are compounded, they play a synergistic role, thereby achieving a better flame retardant effect on silicone materials. The compatibilizer has a good compatibility effect, which can improve the compatibility and dispersion of silicone powder, PI powder, and Teflon powder, so that the obtained modifier can be fully compatible and mixed with the raw material system of silicone materials. It also plays a role in reinforcement, toughening, and flame retardancy of raw rubber, thereby enabling the weather-resistant and flame-retardant silicone material to obtain better flame retardant properties, mechanical properties, and weather resistance.

[0012] The weather-resistant and flame-retardant silicone material obtained in this application is used in charging pile wires and cables in tropical coastal areas, providing better weather resistance. It has higher tolerance to high temperature, strong ultraviolet radiation, and salty environments, reducing the possibility of aging, cracking, and damage, and improving the safety and durability of charging pile wires and cables.

[0013] In summary, the modifier prepared by using silicone powder, PI powder, Teflon powder, and compatibilizer possesses excellent flame retardant properties, toughening and reinforcement, and weather resistance. It can be thoroughly and uniformly mixed with raw rubber, and when combined with hydrogen-containing silicone oil, it further cross-links the raw rubber, adjusts the softness of the raw rubber, and thus enables the prepared silicone material to possess excellent mechanical properties and flame retardant properties. At the same time, it has good resistance to harsh environments such as high temperature, strong ultraviolet radiation, and salt content, further improving the durability and safety of wires and cables made from silicone material.

[0014] Preferably, the compatibilizer is prepared from the following raw materials by weight percentage:

[0015] Unsaturated hydrocarbon siloxanes 7-12%

[0016] Nitrogen-containing siloxanes 1-5%

[0017] 2-Hydroxyethyl methacrylate phosphate 1.8-3%

[0018] 2-5% ethylene acrylate maleic anhydride terpolymer

[0019] Maleic anhydride amino alcohol acrylate 0.5-1.5%

[0020] Catalyst 0.5-1%

[0021] The remainder is solvent.

[0022] In the above technical solution, both unsaturated hydrocarbon siloxanes and nitrogen-containing siloxanes contain Si-O-Si bonds, which have good flame retardancy, heat resistance, salt corrosion resistance and UV resistance. 2-hydroxyethyl methacrylate phosphate contains phosphate groups, which have good flame retardancy. At the same time, the phosphate groups and hydroxyl groups can interact with other groups in the polymer chain, such as forming hydrogen bonds and transesterification reactions, thereby enhancing the performance of the polymer.

[0023] Ethylene-acrylate-maleic anhydride terpolymer (EMH) is a terpolymer composed of ethylene, acrylate, and maleic anhydride. It exhibits excellent adhesion, compatibility with most polymers, and ease of processing. Maleic anhydride-amino alcohol acrylate is a compound containing maleic anhydride, amino, and acrylate groups. It possesses good reactivity and various functional groups, making it suitable for synthesizing polymer materials or as a modifier.

[0024] In summary, this application, with the assistance of catalysts and solvents, enables the blending reaction of unsaturated hydrocarbon siloxanes, nitrogen-containing siloxanes, 2-hydroxyethyl methacrylate phosphate, maleic anhydride amino alcohol acrylate, and ethylene acrylate maleic anhydride terpolymer. The resulting polymer composite contains elements such as silicon, sulfur, and nitrogen, exhibiting excellent flame retardant and weather-resistant properties. Furthermore, it readily adheres to the surfaces of silicone powder, PI powder, and Teflon powder, further improving the compatibility between the modifier and the raw rubber. Consequently, the weather-resistant and flame-retardant silicone material possesses flame retardant properties, mechanical properties, and weather resistance. The resulting wires and cables exhibit excellent resistance to ultraviolet radiation, salt, and heat, reducing the likelihood of cracking and breakage during use.

[0025] Preferably, the unsaturated hydrocarbon siloxane is methacryloxypropyl dimethylmethoxysilane and / or bis-3-methylpropenyloxypropyl tetramethyldisiloxane.

[0026] The reactive groups of methacryloyloxypropyl dimethylmethoxysilane and bis-3-methylpropenyloxypropyltetramethyldisiloxane are located on both sides of the molecular end. When they further crosslink with 2-hydroxyethyl methacrylate phosphate, they form a polymeric complex with a relatively long molecular backbone. Due to its excellent toughening effect, it can further crosslink with nitrosiloxane and maleic anhydride amino alcohol acrylate to form a crosslinked network structure. Combined with ethylene acrylate maleic anhydride terpolymer, the resulting compatibilizer has good compatibility, flame retardancy and toughening properties, thereby promoting the compatibility of silicone powder, PI powder and Teflon powder in the weather-resistant and flame-retardant silicone material raw material system.

[0027] At the same time, it can further improve the flame retardant effect and toughness, so that the weather-resistant flame retardant silicone material can obtain better flame retardant performance, mechanical properties and resistance to salt, ultraviolet rays, etc., reducing the possibility of cracking and damage to charging pile wires and cables in hot coastal areas, and improving their safety and durability.

[0028] When methacryloyloxypropyl dimethylmethoxysilane and bis-3-methylpropenyloxypropyltetramethyldisiloxane are compounded in a weight ratio of 1:(1-4), they have a synergistic effect, further improving the flame retardant, weather resistance and mechanical properties of weather-resistant and flame-retardant silicone materials.

[0029] Preferably, the nitrogen-containing siloxane is one or more of N-(hydroxyethyl)-N,N-bis(trimethoxysilylpropyl)amine, N-(3-trimethoxysilylpropyl)octylamide, and N-(3-trimethoxysilylpropyl)octadecylamide.

[0030] N(hydroxyethyl)-N,N-bis(trimethoxysilylpropyl)amine, N-(3-trimethoxysilylpropyl)octylamide, and N-(3-trimethoxysilylpropyl)octadecylamide all contain active groups, making them prone to cross-linking reactions. Furthermore, these active groups are located in the middle of the molecular chain. Therefore, after the formation of unsaturated hydrocarbon siloxanes and 2-hydroxyethyl methacrylate phosphates, the addition of active groups from nitrogen-containing siloxanes, active groups from maleic anhydride amino alcohol acrylates, and ethylene acrylate maleic anhydride terpolymers, followed by a blending reaction, forms a large molecular polymer complex with an interwoven network structure. This complex contains siloxy groups, nitrogen, and phosphorus, resulting in excellent flame retardant properties. It also promotes the compatibility of silicone powder, PI powder, Teflon powder, and weather-resistant flame-retardant silicone materials, thereby further improving weather resistance, mechanical properties, and flame retardant performance.

[0031] Preferably, the solvent is an ethyl acetate and / or ethanol solution.

[0032] Using ethyl acetate and / or ethanol solution as solvents provides excellent dispersion and dilution for unsaturated hydrocarbon siloxanes, nitrogen-containing siloxanes, 2-hydroxyethyl methacrylate phosphate, ethylene acrylate maleic anhydride terpolymer, and maleic anhydride amino alcohol acrylate, facilitating their blending reaction and making the resulting compatibilizer easier to surface treat silicone powder, PI powder, and Teflon powder. Weather-resistant and flame-retardant silicone materials achieve better mechanical and flame-retardant properties, and exhibit better resistance to salt, ultraviolet, and high-temperature environments. This reduces the need for cables and wires in charging piles used in hot coastal areas, minimizing aging and cracking, thus improving practicality.

[0033] Preferably, the catalyst is benzoyl peroxide.

[0034] Benzoyl peroxide acts as a polymerization initiator and free radical reactant, thereby promoting the blending reaction of unsaturated hydrocarbon siloxanes, nitrogen-containing siloxanes, 2-hydroxyethyl methacrylate phosphate, ethylene acrylate maleic anhydride terpolymer, and maleic anhydride amino alcohol acrylate. This allows the resulting compatibilizer to modify the compatibility of silicone powder, PI powder, and Teflon powder. As a result, the modifier can be fully and uniformly mixed with the raw material system of weather-resistant and flame-retardant silicone materials, while further improving the corresponding physical properties.

[0035] Preferably, the compatibilizer is prepared by the following method:

[0036] Weigh out 2-hydroxyethyl methacrylate phosphate, unsaturated hydrocarbon siloxane, catalyst and solvent, mix them evenly, heat and react for 1-2 hours, add nitrogen-containing siloxane, maleic anhydride amino alcohol acrylate, ethylene acrylate maleic anhydride terpolymer, react for 2-3 hours to obtain compatibilizer.

[0037] The above process is simple to operate. It involves a blending polymerization reaction of 2-hydroxyethyl methacrylate phosphate and unsaturated hydrocarbon siloxane, followed by a further blending and crosslinking reaction of nitrogen-containing siloxane, maleic anhydride amino alcohol acrylate, and ethylene acrylate maleic anhydride terpolymer to form a macromolecular crosslinked network structure polymer complex. This complex exhibits excellent flame retardant properties, toughening effect, weather resistance, and compatibility. It further promotes the compatibility of silicone powder, PI powder, Teflon powder, and weather-resistant flame-retardant silicone materials, and further improves the weather resistance, flame retardant properties, and mechanical properties of weather-resistant flame-retardant silicone materials.

[0038] Preferably, the raw rubber is composed of one or more of methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber.

[0039] Methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber all have good compatibility with modifiers. When methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber are compounded in a weight ratio of 10:2:1:1, their combined properties result in weather-resistant and flame-retardant silicone materials with excellent flame-retardant properties, mechanical properties, and weather resistance.

[0040] Fluorosilicone rubber, also known as γ-trifluoropropylmethylpolysiloxane, is a colorless, transparent, highly viscous, plastic linear polymer compound with 0.2%-0.4% vinylsiloxane copolymerization modification in its molecular chain. The main chain is composed of silicon and oxygen atoms, and the side groups connected to silicon are methyl, vinyl and trifluoropropyl, with a molecular weight of 500,000-800,000.

[0041] Preferably, the processing aids are colorants and / or silica.

[0042] Adding colorants makes it easier to adjust the color of silicone materials, allowing for diverse color variations, while silica acts as a reinforcing agent. Together with modifiers, it improves the mechanical properties of weather-resistant and flame-retardant silicone materials.

[0043] Secondly, this application provides a method for preparing a weather-resistant and flame-retardant silicone material, comprising the following steps:

[0044] Weigh out the silicone powder, PI powder, Teflon powder, and compatibilizer by weight, mix them evenly, and dry them to obtain the modifier.

[0045] Weigh out 5-18% of the modifier and processing aid by weight percentage, mix them evenly to obtain a mixture; weigh out the raw rubber and hydrogen-containing silicone oil, mix them evenly, and then add them to the mixture in batches, mix them evenly, and heat to react to obtain silicone material.

[0046] The above process is simple to operate and has high production efficiency. By adding the mixture in several batches, it is fully compatible and mixed evenly with raw rubber and other materials. The resulting weather-resistant and flame-retardant silicone material has good weather resistance, flame retardancy and mechanical properties.

[0047] In summary, this application has the following beneficial effects:

[0048] 1. The modifier prepared by using silicone powder, PI powder, Teflon powder, and compatibilizer has excellent flame retardant properties, toughening and reinforcement, and weather resistance. It can be fully and evenly mixed with raw rubber, and then combined with hydrogen-containing silicone oil to further crosslink the raw rubber, adjust the softness of the raw rubber, and thus make the silicone material have excellent mechanical properties and flame retardant properties. At the same time, it has good resistance to harsh environments such as high temperature, strong ultraviolet rays, and salt content, further improving the durability and safety of wires and cables made of silicone material.

[0049] 2. This application, with the assistance of a catalyst and solvent, involves the blending reaction of unsaturated hydrocarbon siloxanes, nitrogen-containing siloxanes, 2-hydroxyethyl methacrylate phosphate, and maleic anhydride amino alcohol acrylate, combined with an ethylene acrylate maleic anhydride terpolymer. The resulting polymer composite contains elements such as silicon, sulfur, and nitrogen, resulting in better flame retardant and weather-resistant effects. It also easily adheres to the surface of silicone powder, PI powder, and Teflon powder, further improving the compatibility between the modifier and the raw rubber. Consequently, the weather-resistant and flame-retardant silicone material possesses flame retardant effects, mechanical properties, and weather resistance. The resulting wires and cables exhibit better resistance to ultraviolet light, salt, and heat, reducing cracking and breakage during use. Detailed Implementation

[0050] The present application will be further described in detail below with reference to the embodiments.

[0051] Introduction to some raw materials;

[0052] Table 1. Introduction to Some Raw Materials

[0053]

[0054]

[0055]

[0056] Example of compatibilizer preparation

[0057] Preparation Example 1

[0058] A compatibilizer is prepared by the following method:

[0059] Weigh out 1.8% 2-hydroxyethyl methacrylate phosphate, 0.5% catalyst, 7% unsaturated hydrocarbon siloxane, and 80.2% solvent by weight and place them in a reaction vessel. Stir at 100 r / min for 10 min to ensure thorough mixing. Then heat to 68°C, continue stirring, and react for 1 h. Add 5% ethylene acrylate maleic anhydride terpolymer, 5% nitrogen-containing siloxane, and 0.5% maleic anhydride amino alcohol acrylate, and continue reacting for 3 h. Cool to 30°C to obtain the compatibilizer.

[0060] The unsaturated hydrocarbon siloxane is methacryloxypropyl dimethylmethoxysilane. The nitrogen siloxane is N-(3-trimethoxysilylpropyl)octadecylamide; the solvent is ethyl acetate, and the catalyst is benzoyl peroxide.

[0061] Preparation Example 2

[0062] The difference between Preparation Example 2 and Preparation Example 1 lies in the amount of raw materials and the reaction time. The compatibilizer was prepared by the following method:

[0063] Weigh out 3.8% 2-hydroxyethyl methacrylate phosphate, 0.8% catalyst, 10% unsaturated hydrocarbon siloxane, and 78.4% solvent by weight and place them in a reaction vessel. Stir at 100 r / min for 10 min to ensure thorough mixing. Then heat to 68°C, continue stirring, and react for 2 h. Add 3% ethylene acrylate maleic anhydride terpolymer, 3% nitrogen-containing siloxane, and 1% maleic anhydride amino alcohol acrylate. Continue reacting for 3 h and then cool to 30°C to obtain the compatibilizer.

[0064] Preparation Example 3

[0065] The difference between Preparation Example 3 and Preparation Example 2 is that the amount of raw materials used is different, and the compatibilizer is prepared by the following method:

[0066] Weigh out 5% 2-hydroxyethyl methacrylate phosphate, 1% catalyst, 12% unsaturated hydrocarbon siloxane, and 77.5% solvent by weight and place them in a reaction vessel. Stir at 100 r / min for 10 min to ensure thorough mixing. Then heat to 68°C, continue stirring, and react for 2 h. Add 5% ethylene acrylate maleic anhydride terpolymer, 5% nitrogen-containing siloxane, and 0.5% maleic anhydride amino alcohol acrylate, and continue reacting for 3 h. Cool to 30°C to obtain the compatibilizer.

[0067] Preparation Example 4

[0068] The difference between Preparation Example 4 and Preparation Example 3 is that the unsaturated hydrocarbon siloxane is composed of methacryloyloxypropyl dimethylmethoxysilane and bis-3-methylpropenyloxypropyltetramethyldisiloxane in a weight ratio of 1:3.

[0069] Preparation Example 5

[0070] The difference between Preparation Example 5 and Preparation Example 4 is that the nitrosiloxane is composed of N-(hydroxyethyl)-N,N-bis(trimethoxysilylpropyl)amine, N-(3-trimethoxysilylpropyl)octylamide, and N-(3-trimethoxysilylpropyl)octadecylamide in a weight ratio of 1:1:2.

[0071] Preparation of comparative examples

[0072] Preparation of Comparative Example 1

[0073] The difference between Comparative Example 1 and Preparation Example 1 is that unsaturated hydrocarbon siloxanes are replaced with nitrogen-containing siloxanes in equal amounts.

[0074] Preparation of Comparative Example 2

[0075] The difference between Comparative Example 2 and Example 1 is that nitrogen-containing siloxanes are replaced with unsaturated hydrocarbon siloxanes in equal amounts.

[0076] Preparation of Comparative Example 3

[0077] The difference between Comparative Example 3 and Preparation Example 1 is that 2-hydroxyethyl methacrylate phosphate is replaced by an equal amount of ethylene acrylate maleic anhydride terpolymer.

[0078] Preparation of Comparative Example 4

[0079] The difference between Comparative Example 4 and Preparation Example 1 is that maleic anhydride amino alcohol acrylate was replaced in equal amounts with ethylene acrylate maleic anhydride terpolymer.

[0080] Example

[0081] Example 1

[0082] A weather-resistant and flame-retardant silicone material is prepared by the following method:

[0083] Weigh out silicone powder, PI powder, Teflon powder and compatibilizer in a weight ratio of 1:1:3:1 and put them into a stirring device. Stir at 100 r / min for 20 min to make them fully mixed. Heat to 120℃ and distill under reduced pressure for 1 h to make the solvent evaporate completely. Then put it into an oven at 50℃ for 2 h to dry to obtain the modifier.

[0084] Weigh out 10% of the modifier and 7% of the processing aid by weight percentage, mix them evenly to obtain a mixture;

[0085] Weigh out 75% raw rubber and 8% hydrogen-containing silicone oil by weight percentage and put them into a kneader. Mix them for 10 minutes at a speed of 50 r / min to ensure they are fully mixed. Heat the mixture at 3℃ / min. When the temperature reaches 100℃, add the mixture in two equal portions. After each addition, continue stirring for 30 minutes to ensure it is fully mixed. After all the mixture has been added, raise the temperature to 150℃ and react for 2 hours to obtain 10 kg of weather-resistant and flame-retardant silicone material.

[0086] The raw rubber is methyl vinyl silicone rubber; the processing aid is obtained by mixing pigments and silica in a weight ratio of 1:10. The compatibilizer is obtained by uniformly mixing vinyltrimethoxysilane and a 75% alcohol solution.

[0087] Example 2

[0088] The difference between Example 2 and Example 1 lies in the amount of raw materials used, as detailed below:

[0089] Modifier 18%, processing aid 12%, raw rubber 65%, hydrogen-containing silicone oil 5%.

[0090] Example 3

[0091] The difference between Example 3 and Example 1 lies in the amount of raw materials used, as detailed below:

[0092] Modifier 5%, processing aid 5%, raw rubber 80%, hydrogen-containing silicone oil 10%.

[0093] Example 4

[0094] The difference between Example 4 and Example 1 is that the weight ratio of silicone powder, PI powder, Teflon powder, and compatibilizer is 1:3:5:2.

[0095] Example 5

[0096] The difference between Example 5 and Example 4 is that the raw rubber is composed of methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber in a weight ratio of 10:2:1:1.

[0097] Examples 6-14

[0098] The difference between Examples 6-14 and Example 5 is that the source of the compatibilizer is different, as shown in Table 2.

[0099] Examples 6-14 Table 2 Source of compatibilizer

[0100] Example Sources of compatibilizers Example 6 Preparation Example 1 Example 7 Preparation Example 2 Example 8 Preparation Example 3 Example 9 Preparation Example 4 Example 10 Preparation Example 5 Example 11 Preparation of Comparative Example 1 Example 12 Preparation of Comparative Example 2 Example 13 Preparation of Comparative Example 3 Example 14 Preparation of Comparative Example 4

[0101] Comparative Example

[0102] Comparative Example 1

[0103] The difference between Comparative Example 1 and Example 1 is that Teflon powder was replaced with PI powder in equal amounts.

[0104] Comparative Example 2

[0105] The difference between Comparative Example 2 and Example 1 is that the PI powder was replaced with an equal amount of Teflon powder.

[0106] Comparative Example 3

[0107] The difference between Comparative Example 3 and Example 1 is that silicone powder, PI powder, and Teflon powder are replaced with antimony trioxide in equal amounts.

[0108] Performance testing

[0109] Test Method / Experimental Method: Weigh the weather-resistant and flame-retardant silicone materials obtained in Examples 1-14 and Comparative Examples 1-4 and the bis(2,5) vulcanizing agent at a weight ratio of 100:2.5 and put them into a two-roll mill for mixing until the weather-resistant and flame-retardant silicone materials and the bis(2,5) vulcanizing agent are fully mixed and uniform to obtain a compound. Then, put the compound into a mold and transfer the mold to a flat vulcanizing agent at 220°C for molding for 3 minutes. After cooling to room temperature, demold to obtain the test sample for the following experiments.

[0110] Experiment (1)

[0111] The test samples obtained in Examples 1-14 and Comparative Examples 1-4 were placed in an environment with a temperature of 25°C and a humidity of 60% for 24 hours before their tensile strength, elongation, and oxygen index were tested.

[0112] Experiment (II)

[0113] The test samples obtained from Examples 1-14 and Comparative Examples 1-4 were placed in an aging chamber for weather resistance testing. Test conditions: 24 hours per cycle, for a total of 21 cycles.

[0114] Among them, ultraviolet irradiation for 12 hours (lamp UVA-340nm, power 0.63W / (m²)) 2 (nm), salt spray is introduced, with humidity maintained at 60% and salt content at 1%), and humidified for 12 hours (salt spray is introduced, with humidity maintained at 85% and salt content at 1%, and temperature maintained at 85℃). Each cycle of testing is repeated until the test is completed.

[0115] Test the tensile strength, elongation and oxygen index after weathering treatment, and calculate the residual tensile strength, residual elongation and residual oxygen index respectively. Taking the residual tensile strength as an example, the calculation formula is the tensile strength after weathering treatment divided by the tensile strength obtained in experiment (1) and then multiplied by 100%.

[0116] The tensile strength and elongation of Experiments (I) and (II) were tested in accordance with GB / T 528-1998, and the oxygen index was tested in accordance with ISO4589-2. The specific data are shown in Table 3.

[0117] Table 3 Experimental data for Examples 1-14 and Examples 1-4

[0118]

[0119]

[0120] Combining Example 1 and Comparative Examples 1-3 with Table 3, it can be seen that the tensile strength, elongation, oxygen index, tensile strength residual, elongation residual, and oxygen index residual of Comparative Examples 1-3 are all lower than those of Example 1. This indicates that the compounding of silicone powder, PI powder, and Teflon powder in this application achieves a better synergistic effect, enabling the silicone material to possess flame retardant effect, mechanical properties, and weather resistance. Furthermore, even after aging treatment, it maintains a good residual rate, indicating that the silicone material prepared in this application has good resistance to salt content, high temperature, high humidity, and strong ultraviolet radiation. Therefore, when applied to charging pile cables in hot coastal areas, it reduces damage and cracking, improving durability and safety.

[0121] Combining Examples 2 and 5 with Table 3, it can be seen that the tensile strength, elongation, oxygen index, tensile strength residual, elongation residual, and oxygen index residual of Example 2 are all lower than those of Example 5. This indicates that the compounding of methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber has a synergistic effect, resulting in a silicone material with better mechanical properties, flame retardant properties, and weather resistance.

[0122] Combining Examples 5 and 6-8 with Table 3, it can be seen that the tensile strength, elongation, oxygen index, tensile strength residual, elongation residual, and oxygen index residual of Examples 6-8 are all higher than those of Example 5. This indicates that the compatibilizer prepared in this application, and the modifier prepared by blending with silicone powder, PI powder, and Teflon powder, have a better compatibility effect on the raw material system of the weather-resistant and flame-retardant silicone material, further improving the mechanical properties and flame-retardant properties of the weather-resistant and flame-retardant silicone material, and exhibiting better resistance to environments containing salt, high temperature, high humidity, and strong ultraviolet radiation, reducing the occurrence of damage and cracking in the manufactured wires and cables, and improving their durability.

[0123] Combining Examples 6 and 11-14 with Table 3, it can be seen that the tensile strength, elongation, oxygen index, residual tensile strength, residual elongation, and residual oxygen index of Examples 11-14 are all lower than those of Example 6. This indicates that when the compatibilizer prepared by the blending reaction of unsaturated hydrocarbon siloxanes, nitrogen-containing siloxanes, 2-hydroxyethyl methacrylate phosphate, maleic anhydride amino alcohol acrylate, and ethylene acrylate maleic anhydride terpolymer in this application has a better compatibility-promoting effect on silicone powder, PI powder, and Teflon powder, the modifier and weather-resistant flame-retardant silicone material are fully and uniformly mixed, further improving the mechanical properties, flame-retardant properties, and weather resistance of the weather-resistant flame-retardant silicone material. This improves its durability and safety when applied to charging pile cables in coastal areas.

[0124] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A weather-resistant and flame-retardant silicone material, characterized in that, It is made from the following raw materials by weight percentage: Raw rubber 65-80% Hydrogen-containing silicone oil 5-10% Modifier 5-18% The remainder is processing aids; The modifier is prepared by mixing silicone powder, PI powder, Teflon powder, and compatibilizer in a weight ratio of 1:(1-3):(3-5):(1-2). The compatibilizer is prepared from the following raw materials by weight percentage: Unsaturated hydrocarbon siloxanes 7-12% Nitrogen-containing siloxanes 1-5% 2-Hydroxyethyl methacrylate phosphate 1.8-3% 2-5% ethylene acrylate maleic anhydride terpolymer Maleic anhydride amino alcohol acrylate 0.5-1.5% Catalyst 0.5-1% The remainder is solvent; The unsaturated hydrocarbon siloxane is methacryloxypropyl dimethylmethoxysilane and / or bis-3-methylpropenyloxypropyl tetramethyldisiloxane; The nitrogen-containing siloxane is one or more of N-(hydroxyethyl)-N,N-bis(trimethoxysilylpropyl)amine, N-(3-trimethoxysilylpropyl)octylamide, and N-(3-trimethoxysilylpropyl)octadecylamide.

2. The weather-resistant and flame-retardant silicone material according to claim 1, characterized in that: The solvent is an ethyl acetate and / or ethanol solution.

3. The weather-resistant and flame-retardant silicone material according to claim 1, characterized in that: The catalyst is benzoyl peroxide.

4. A weather-resistant and flame-retardant silicone material according to any one of claims 1-3, characterized in that, The compatibilizer is prepared by the following method: Weigh out 2-hydroxyethyl methacrylate phosphate, unsaturated hydrocarbon siloxane, catalyst and solvent, mix them evenly, heat and react for 1-2 hours, add nitrogen-containing siloxane, maleic anhydride amino alcohol acrylate, ethylene acrylate maleic anhydride terpolymer, react for 2-3 hours to obtain compatibilizer.

5. The weather-resistant and flame-retardant silicone material according to claim 1, characterized in that: The raw rubber is composed of one or more of the following: methyl vinyl silicone rubber, phenyl silicone rubber raw rubber, hydroxyl-terminated polydimethylsiloxane, and fluorosilicone rubber.

6. The weather-resistant and flame-retardant silicone material according to claim 1, characterized in that: The processing aids are colorants and / or silica.

7. A method for preparing a weather-resistant and flame-retardant silicone material as described in any one of claims 1-6, characterized in that, Includes the following steps: Weigh out the silicone powder, PI powder, Teflon powder, and compatibilizer by weight, mix them evenly, and dry them to obtain the modifier. Weigh out the modifier and processing aid by weight percentage and mix them evenly to obtain a mixture; weigh out the raw rubber and hydrogen-containing silicone oil and mix them evenly, then add them to the mixture in batches and mix them evenly. Heat the mixture to react and obtain the silicone material.

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