High-transparency silicone rubber material and preparation method thereof

Abstract

The invention provides a high-transparency silicone rubber material and a preparation method thereof. The silicone rubber material is prepared from the following raw materials in parts by mass: 100 parts of methyl vinyl phenyl rubber, 10-30 parts of modified white carbon black, 3-5 parts of vinyl MQ silicon resin, 4-6 parts of polymethylhydrosiloxane, 1-1.5 parts of vinyl hydroxyl silicone oil and 0.001-0.003 part of a platinum catalyst. Wherein the modified white carbon black is obtained by modifying white carbon black through a benzotriazole silane coupling agent and a silicone oil grafted silane coupling agent; the benzotriazole silane coupling agent is obtained by carrying out carbamate reaction on a hydroxyl benzotriazole compound and an isocyanate silane coupling agent; the silicone oil grafted silane coupling agent is obtained by carrying out addition reaction on hydrogen-terminated polydimethylsiloxane and a vinyl silane coupling agent. The silicone rubber material has good transparency and light stability.

Description

Technical Field

[0001] This application relates to the field of silicone rubber technology, specifically to a highly transparent silicone rubber material and its preparation method. Background Technology

[0002] Silicone rubber, due to its excellent heat resistance, electrical insulation, flexibility, and chemical stability, is widely used in optoelectronic devices, LED packaging, medical consumables, and transparent structural components—fields with high requirements for optical performance and long-term reliability. For these applications, in addition to basic mechanical properties, materials must possess high transparency and good light stability. However, many factors affect the transparency and optical stability of silicone rubber, including filler particle size and agglomeration, filler / matrix refractive index differences, interfacial compatibility, the water absorption of silica, and slight yellowing under light. Therefore, the preparation of highly transparent silicone rubber remains a key focus of industry research.

[0003] Existing transparent silicone rubbers typically improve transparency by reducing filler aggregation, improving the compatibility between fillers and silicone rubber interfaces, and optimizing cross-linking structures. For example, CN114686001A reduces light scattering caused by water absorption by improving the hydrophobicity of precipitated silica; CN116396619A balances transparency and mechanical properties by adjusting the reinforcing structure; and CN116987389A focuses on improving light transmittance by improving the dispersion state of silica. All of these technical solutions improve the optical properties of transparent silicone rubber to some extent.

[0004] However, existing technologies still have the following shortcomings. For example, silica, a commonly used reinforcing filler in transparent silicone rubber, is prone to agglomeration due to its high surface hydroxyl density and strong adsorption. Even with surface treatment, uneven processing may occur, leading to a mismatch between the local refractive index of the filler and the silicone rubber matrix, resulting in light scattering points and limiting the material's transparency. Furthermore, the siloxane backbone is prone to free radical reactions under ultraviolet or high-energy visible light (such as blue light), causing changes in the cross-linking structure, which may lead to slight yellowing or a decrease in light transmittance. Existing technologies often employ conventional antioxidants or simple coating measures to mitigate the effects of such light exposure, but their long-term photostability improvement is limited, and transparency still tends to decrease under prolonged light exposure.

[0005] In summary, although existing technologies have improved transparent silicone rubber through filler treatment, dispersion optimization, and formulation control, there are still shortcomings in further enhancing transparency, improving light stability, and maintaining long-term optical performance. Therefore, a silicone rubber material that can simultaneously achieve high transparency and excellent light stability is needed. Summary of the Invention

[0006] This application provides a highly transparent silicone rubber material and its preparation method, aiming to solve the technical problems existing in the current transparent silicone rubber, such as low transparency, unstable filler interface, easy yellowing under light conditions, and insufficient long-term optical performance retention.

[0007] In a first aspect, this application provides a highly transparent silicone rubber material, comprising the following raw materials in parts by weight: 100 parts methyl vinyl phenyl rubber, 10-30 parts modified silica, 3-5 parts vinyl MQ silicone resin, 4-6 parts polymethyl hydrosiloxane, 1-1.5 parts vinyl hydroxyl silicone oil, 0.001-0.003 parts platinum catalyst; The modified silica is obtained by modifying silica with benzotriazole silane coupling agent and silicone oil grafted silane coupling agent; the benzotriazole silane coupling agent is obtained by reacting hydroxybenzotriazole compounds with isocyanate silane coupling agents in a carbamate reaction; the silicone oil grafted silane coupling agent is obtained by reacting hydrogen-terminated polydimethylsiloxane with vinyl silane coupling agent in an addition reaction.

[0008] According to this application, by introducing a modified interface layer constructed by introducing a benzotriazole silane coupling agent and a silicone oil-grafted silane coupling agent onto the surface of silica, the dispersibility and interface stability of the filler in the silicone rubber matrix can be significantly improved, thereby effectively reducing the interface refractive index difference and light scattering caused by filler aggregation, and achieving high transparency of the silicone rubber material; at the same time, the benzotriazole structure can reduce the structural changes caused by the interfacial photoexcitation reaction under light irradiation, thereby improving the optical retention and yellowing inhibition ability of the material under long-term light irradiation.

[0009] Specifically, methyl vinyl phenyl rubber, as the silicone rubber matrix, provides the material with good transparency and basic mechanical properties. Modified silica serves as the reinforcing phase, where the benzotriazole silane coupling agent forms a stable light absorption and energy dissipation layer on the silica surface. The benzotriazole structure exhibits higher interfacial compatibility with siloxane groups and is less prone to forming polar enrichment regions on the silica surface, thus better maintaining the uniformity of the interfacial refractive index. Furthermore, the benzotriazole structure does not adversely interact with the platinum catalyst in the addition curing system, ensuring uniform crosslinking. The light absorption and energy dissipation effects of benzotriazole also suppress the filler-matrix interface under illumination. The generation of trace free radicals enables the material to maintain higher optical stability under blue or ultraviolet light irradiation. The flexible siloxane segments introduced by the silicone oil-grafted silane coupling agent have similar chemical composition and refractive index to the silicone rubber matrix, which can construct a flexible compatibility layer, improving the spreadability and interface coverage of the filler during the mixing process. The synergistic effect of the two types of silane coupling agents forms a composite structure of "rigid light-stabilized layer + flexible matching layer" on the filler surface. On the one hand, it achieves deep passivation of the hydroxyl groups on the surface of silica, reducing light scattering caused by polarity differences. On the other hand, it improves the interfacial optical consistency through the smooth transition of the refractive index gradient, thereby significantly improving the transmittance and transparency of the material. This composite interface structure can also improve the uniformity of interfacial crosslinking during the addition curing process, avoiding microscopic scattering points caused by local crosslinking density differences, and maintaining higher optical uniformity and transparency of the material.

[0010] It is also worth noting that although benzotriazole compounds have strong coordination ability in the free state, affecting the catalytic effect of Karstedt-type platinum catalysts, in this application, good curing can still be achieved in the presence of benzotriazole-modified silica. The reason may be that the benzotriazole group is linked to the silane coupling agent molecule by urethane bonds and is further fixed on the silica surface by hydrolysis and condensation. Its coordination electron density is significantly reduced, and the interface layer formed by siloxane bonds is spatially separated from the continuous silicone rubber phase in which the platinum catalyst is located. It is not a free compound. In addition, the flexible PDMS interface layer constructed on the silica surface by silicone oil-grafted silane coupling agent further blocks the direct contact between benzotriazole and the catalyst. Therefore, the modified silica in this application maintains a good curing level while improving the long-lasting transparency.

[0011] Vinyl MQ silicone resin can form a uniform network reinforcing structure with the silicone rubber matrix, improving the material's mechanical properties without significantly affecting transparency. Polymethylhydrosiloxane acts as an addition crosslinking agent, enabling the material to form a three-dimensional crosslinked network through addition reactions. Vinyl hydroxyl silicone oil helps regulate the system's rheological properties and crosslinking uniformity. A platinum catalyst promotes the addition reaction between vinyl groups and Si-H, resulting in a rapid and uniform curing process. The synergistic effect among these components allows the silicone rubber material to possess both excellent transparency and light stability.

[0012] In some embodiments, the benzotriazole silane coupling agent is prepared by dispersing a hydroxybenzotriazole compound and an isocyanate silane coupling agent in toluene and reacting them at 25-35°C for 1-3 hours to obtain the benzotriazole silane coupling agent.

[0013] In some of the above embodiments, by linking hydroxybenzotriazole compounds with isocyanate silane coupling agents via urethane bonds under mild conditions, the benzotriazole structure can be stably covalently fixed within the silane molecule, avoiding group desorption or structural damage caused by light, heat, or oxygen conditions. This ensures the effective fixation of the anti-photoaging structure on the silica surface. Compared to directly physically incorporating benzotriazole into silicone rubber, the silanized structure constructed by this method can form a denser and more uniform interfacial layer after hydrolysis and condensation, improving the surface coverage of silica and reducing polar residual areas. This is beneficial for improving the dispersibility of fillers in silicone rubber and the consistency of interfacial refractive index, thereby further improving the transparency and light stability of the material.

[0014] In some embodiments, the hydroxybenzotriazole compound is obtained by Williamson etherification of 2-(2-hydroxy-5-methylphenyl)benzotriazole and bromopropanol.

[0015] In some of the embodiments described above, additional o-phenyl and methyl substitutions are introduced into the 2-(2-hydroxy-5-methylphenyl)benzotriazole structure, resulting in a larger conjugated skeleton and greater steric hindrance for the benzotriazole group. This structure, on the one hand, improves the absorption capacity for ultraviolet and high-energy blue light, forming a more stable photostable layer at the filler interface; on the other hand, due to the restraining effect of the added aromatic ring on the lone pair electrons of the triazole ring and its significant steric hindrance, its catalytic interference with the Karstedt platinum catalyst is further reduced.

[0016] Furthermore, the inventors discovered that, compared to the direct reaction of unmodified 2-(2-hydroxy-5-methylphenyl)benzotriazole with isocyanate silane, the hydroxybenzotriazole obtained by Williamson etherification is more beneficial in improving the light stability and long-term transparency of the transparent silicone rubber material of this application. This may be because, by etherifying 2-(2-hydroxy-5-methylphenyl)benzotriazole with bromopropanol, a flexible alkoxy chain containing a hydroxyl group can be introduced into the molecule, forming a flexible bridge chain of appropriate length between the benzotriazole group and the silane backbone. This structure can provide reactive sites for isocyanate and improve the spreadability of benzotriazole on the surface of silica, reducing interfacial accumulation and orientation unevenness caused by the high rigidity of the benzotriazole bulk, improving the continuity of the interfacial layer, enhancing optical stability, and thus further optimizing the maintenance of long-term optical performance. Furthermore, the Williamson etherification reaction is characterized by high selectivity and few side reactions. It can construct stable ether bonds under mild conditions, thus preserving the light absorption structure of benzotriazole and providing good reactivity for the subsequent preparation of benzotriazole silane coupling agents.

[0017] Therefore, compared with unetherified benzotriazole, hydroxybenzotriazole obtained by Williamson etherification is more suitable for the transparent silicone rubber system of this application in terms of interface coverage, reaction controllability and light stability.

[0018] In some embodiments, the molar ratio of the hydroxybenzotriazole compound and the isocyanate silane coupling agent is 1:1 to 1.02, and the solid content of the reaction system is 40wt% to 50wt%.

[0019] In some of the above embodiments, controlling the reaction of hydroxybenzotriazole compounds with isocyanate silane coupling agents at a basically equimolar ratio ensures more complete formation of carbamate bonds and avoids side reactions or cross-linking tendencies caused by excess isocyanate. When isocyanate is slightly in excess, it can also compensate for the incomplete local reaction that may be caused by the large steric hindrance of hydroxybenzotriazole molecules, making the final benzotriazole silane coupling agent structure more stable and with less monomer residue. In addition, controlling the solid content of the reaction system within the range of 40wt%~50wt% ensures sufficient dissolution and dispersion of hydroxybenzotriazole while maintaining appropriate fluidity of the silane coupling agent, improving reaction contact efficiency, and reducing incomplete reaction due to too low concentration or partial condensation of silane due to too high concentration. This results in the obtained benzotriazole silane having good structural uniformity and stability in use, which in turn helps to improve the transparency, interfacial refractive index consistency, and light stability of the final silicone rubber material.

[0020] In some embodiments, the silicone oil-grafted silane coupling agent is prepared by dispersing hydrogen-terminated polydimethylsiloxane, vinyl silane coupling agent and Karstedt catalyst in toluene and reacting at 70-90°C for 3-5 hours to obtain the silicone oil-grafted silane coupling agent.

[0021] In some of the above embodiments, by carrying out an addition reaction between hydrogen-capped polydimethylsiloxane and a vinylsilane coupling agent in the presence of a Karstedt catalyst, a hydrolyzable silane structure can be introduced into the end of the PDMS chain segment, giving the resulting coupling agent both flexible siloxane segments and silane interfacial reactive groups. The silicone oil-grafted silane coupling agent prepared by the above addition reaction not only maintains the flexible characteristics of the polydimethylsiloxane segments and has high compatibility with the silicone rubber matrix, but also achieves strong grafting on the silica surface through the participation of silane groups in hydrolysis and condensation, effectively improving the flexibility and chemical bonding of the filler interfacial layer, and enhancing the spreadability and dispersion stability of the filler in silicone rubber. The coupling agent obtained in this embodiment can form a more stable flexible interfacial layer on the filler surface, making the interfacial refractive index closer to that of the silicone rubber matrix, thereby further improving the transparency and long-term optical stability of the material.

[0022] In some embodiments, the number average molecular weight of the hydrogen-capped polydimethylsiloxane is 1000-2000; the molar ratio of the hydrogen-capped polydimethylsiloxane to the vinylsilane coupling agent is 1:1-1.02; the concentration of the Karstedt catalyst in the reaction system is 0.001wt%-0.01wt%; and the solid content of the reaction system is 20wt%-40wt%.

[0023] In some of the above embodiments, the molecular weight of hydrogen-capped polydimethylsiloxane is controlled within the range of 1000-2000. This allows the PDMS segments to maintain their flexibility while possessing a suitable molecular size, enabling them to form an effective flexible coating layer on the surface of silica. This avoids insufficient interfacial stability due to excessively short segments, or restricted condensation reactions due to excessively long segments, thus preventing impact on grafting efficiency. Maintaining a molar ratio of hydrogen-capped PDMS to vinyl silane coupling agent of 1:1 to 1:1.02 ensures a more complete Si-H / C=C addition reaction, preventing unadded Si-H residue due to insufficient vinyl groups. Controlling the Karstedt catalyst concentration within the range of 0.001wt% to 0.01wt% ensures efficient addition reaction and a more uniform and stable structure of the silicone oil-grafted silane coupling agent. The solid content of the reaction system is controlled at 20wt%~40wt%. This can ensure the fluidity and mixing efficiency of the reactants, avoid silane condensation side reactions caused by excessive solid content, and also prevent the problem of decreased reaction efficiency or uneven distribution of molecular chain segments caused by excessively low solid content.

[0024] Therefore, by controlling the molecular weight of hydrogen-terminated polydimethylsiloxane, the molar ratio of the addition reaction, and the amount of Karstedt catalyst used, and limiting the solid content of the reaction to a suitable range, the resulting silicone oil-grafted silane coupling agent can have a more uniform molecular structure and higher grafting efficiency, making the flexible interface layer formed on the surface of silica more complete and continuous, thereby further improving the optical properties and long-term stability of silicone rubber materials.

[0025] In some embodiments, the modified silica is prepared by the following steps: S1: Disperse silica and benzotriazole silane coupling agent in an aqueous ethanol solution, and then hydrolyze and condense the benzotriazole silane coupling agent to graft onto the surface of silica to obtain benzotriazole-grafted silica. S2: The benzotriazole-grafted silica and the silicone oil-grafted silane coupling agent are dispersed in an ethanol aqueous solution, and the silicone oil-grafted silane coupling agent is hydrolyzed and condensed to graft onto the surface of silica to obtain modified silica.

[0026] In some of the above embodiments, by preferentially hydrolyzing and condensing the benzotriazole silane coupling agent onto the surface of silica in the first step, an initial interface layer dominated by benzotriazole groups can be formed on the filler surface. Since the benzotriazole structure has a strong ability to absorb high-energy photons and can suppress the generation of photoexcited free radicals on the silica surface through energy dissipation, this step can effectively reduce the photosensitivity of silica under ultraviolet and blue light conditions. Furthermore, the benzotriazole silane coupling agent can undergo a highly efficient condensation reaction with the hydroxyl groups on the silica surface, allowing the benzotriazole structure to be firmly attached to the filler surface in a covalent bond form, improving the stability of the interface layer. Simultaneously, this interface layer can significantly reduce the polarity of the silica surface, making it easier for subsequent silicone oil-grafted silanes to spread and graft onto the surface, reducing localized insufficient condensation or uneven coverage caused by differences in surface polarity.

[0027] Therefore, by using benzotriazole silane coupling agent as the first step in modifying the surface of silica, a stable and uniform light-stabilized layer can be obtained on the filler surface. This not only effectively inhibits the structural degradation of the filler interface under light conditions but also reduces the agglomeration tendency of silica itself. Combined with the flexible matching layer constructed by silicone oil grafted silane coupling agent in the second step, the refractive index consistency of the filler interface can be further improved, significantly enhancing the dispersibility and transparency of silica in silicone rubber, thereby enhancing the light stability and long-term light transmittance of the final silicone rubber material.

[0028] In some embodiments, the modified silica is prepared by the following steps: S1: 100 parts of silica with an average particle size of 10-20 nm and 6-10 parts of benzotriazole silane coupling agent are dispersed in 400-600 parts of ethanol aqueous solution and reacted at 50-70℃ for 2-4 h to obtain benzotriazole grafted silica. S2: Disperse 100 parts of benzotriazole-grafted silica and 4-6 parts of silicone oil-grafted silane coupling agent in 400-600 parts of ethanol aqueous solution, and react at 50-70℃ for 3-5 hours to obtain modified silica.

[0029] In some of the above embodiments, the amount of benzotriazole silane coupling agent in the first step is controlled at 6-10 parts. This allows the benzotriazole silane to preferentially undergo hydrolysis and condensation with some of the hydroxyl groups on the surface of silica, forming an initial interface layer dominated by benzotriazole groups. At the same time, a certain number of unreacted silanol sites are still retained, facilitating the continued condensation of silicone oil-grafted silane in the second step. This "partial coverage + uniform distribution" structure can effectively reduce the polarity of the silica surface, improve the dispersion stability of the filler, and provide reasonable chemical sites for constructing the flexible siloxane interface layer in the second step.

[0030] In the second step, the silicone oil-grafted silane coupling agent continues to hydrolyze and condense at the residual silanol sites, forming a flexible siloxane matching layer outside the initial benzotriazole layer, making the interfacial refractive index closer to that of the silicone rubber matrix. This layer provides both flexibility and improved interfacial compatibility, making the filler easier to disperse during compounding.

[0031] Therefore, through the above-mentioned preferred two-step modification method, a composite interface structure consisting of a "benzotriazole light-stabilizing layer + silicone oil flexible matching layer" can be constructed on the surface of silica, effectively taking into account light stability, refractive index consistency and dispersion, thereby further improving the transparency and long-term optical stability of the final silicone rubber material.

[0032] In some embodiments, the methyl vinyl phenyl rubber has a viscosity of 10~50 Pa·s at 25°C, a vinyl content of 0.1mol%~0.3mol%, and a phenyl content of 4mol%~8mol%. Based on the above embodiments, the appropriate viscosity and vinyl content can ensure that the silicone rubber matrix has good flow and dispersion during mixing, making it easier for the modified silica to spread evenly in the system; controlling the phenyl content within a certain range can improve the refractive index matching degree between the matrix and the filler interface, allowing the material to maintain more stable optical properties while maintaining high transparency.

[0033] In some embodiments, the vinyl MQ silicone resin has a viscosity of 5000~15000 mPa·s at 25°C, an M / Q ratio of 0.7~0.9, and a vinyl content of 0.5~2wt%. Based on the above embodiments, a suitable viscosity and M / Q ratio can enable the MQ structure to form a uniform and dense three-dimensional reinforcing network, improving the transparency and mechanical strength of the molded silicone rubber; maintaining the vinyl content within a suitable range allows for a more uniform addition reaction with the matrix.

[0034] In some embodiments, the polymethylhydrosiloxane has a viscosity of 0.01~0.1 Pa·s at 25°C and a hydrogen content of 0.1wt%~1wt%. Based on the above embodiments, low-viscosity PMHS can be rapidly dispersed in the compounding process and participate in addition curing, making the crosslinked network more uniform; controlling the hydrogen content within an appropriate range can avoid local over- or under-crosslinking, ensuring a stable and consistent refractive index of the cured film, which helps to improve the transparency and light stability of the entire material.

[0035] In some embodiments, the vinyl hydroxyl silicone oil has a viscosity of 20~100 mPa·s at 25°C, a vinyl content of 6mol%~7mol%, and a hydroxyl content of 5.5mol%~6.5mol%. Based on the above embodiments, the vinyl hydroxyl silicone oil can both supplement the crosslinking active sites and potentially enhance the density of flexible segments at the interface through the formation of an auxiliary effect between the hydroxyl groups and the filler, thereby supplementing passivation. Controlling its viscosity and vinyl content within a suitable range can improve crosslinking uniformity, reduce interfacial light scattering points, and thus improve transparency.

[0036] In some embodiments, the vinyl hydroxyl silicone oil has a viscosity of 20-100 mPa·s at 25°C, and the vinyl platinum catalyst includes a Karstedt catalyst. Based on the above embodiments, the Karstedt catalyst has efficient and mild addition catalytic activity, enabling the silicone rubber system to achieve full crosslinking with a low catalyst dosage, thereby improving the transparency and light stability of the material.

[0037] Secondly, this application provides a method for preparing a highly transparent silicone rubber material, comprising: Provide raw materials for the silicone rubber according to any embodiment of the first aspect; The raw materials are mixed and cured to obtain a highly transparent silicone rubber material.

[0038] According to this application, by sequentially mixing, uniformly dispersing, and adding and curing the matrix rubber, modified silica, silicone resin, silane crosslinking agent, and platinum catalyst according to the formulation system described in the first aspect, a uniform and continuous three-dimensional siloxane network structure can be constructed during the curing process, and a composite interface system of "benzotriazole light-stabilizing layer - silicone oil flexible matching layer" can be formed at the filler interface. This method not only ensures uniform dispersion of the filler during the mixing process, maintaining a stable and consistent interfacial refractive index, thus resulting in higher transparency of the cured silicone rubber material, but also maintains the chemical stability of the interface after curing, improving the material's resistance to yellowing and long-term optical stability under light exposure. Therefore, the silicone rubber material prepared by the method of this application can achieve superior comprehensive performance in terms of transparency and light stability.

[0039] Compared with the prior art, the beneficial effects of this application are at least as follows: By simultaneously employing benzotriazole silane coupling agents and silicone oil-grafted silane coupling agents to perform dual interfacial modification of silica, a composite interfacial layer with both photostability and refractive index matching effects can be constructed on the filler surface. This results in higher dispersion uniformity and interfacial stability of silica in silicone rubber, significantly reducing light scattering and improving material transparency. Simultaneously, the benzotriazole structure can suppress light-induced color change and synergistically works with silicone oil segments to effectively improve the long-term optical stability of silicone rubber under ultraviolet and high-energy blue light conditions. Combined with an optimized silicone rubber matrix and crosslinking system, the resulting silicone rubber material exhibits higher transparency, better interfacial stability, and improved photostability, thereby enhancing its application performance and lifespan in optoelectronic displays, LED packaging, and high-end transparent products. Detailed Implementation

[0040] The various embodiments or implementation schemes in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments.

[0041] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0043] In this specification, unless otherwise specified, "parts" refers to "parts by weight".

[0044] The following describes embodiments of this application. The embodiments described below are exemplary and are only used to explain this application, and should not be construed as limiting this application. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all conventional products that can be obtained commercially.

[0045] 2-(2-hydroxy-5-methylphenyl)benzotriazole, CAS number 2440-22-4; Bromopropanol, also known as 3-bromo-1-propanol, has the CAS number 627-18-9. Propyltriethoxysilane isocyanate, CAS number 24801-88-5; Vinyltrimethoxysilane, CAS number 2768-02-7; The silica, model number Jiupeng CY-SP15, has an average particle size of 15nm. Methyl vinyl phenyl rubber has a viscosity of 40 Pa·s at 25°C, a vinyl content of 0.2 mol%, and a phenyl content of 6%. Vinyl MQ silicone resin, also known as methyl vinyl MQ silicone resin, has a viscosity of 9000 mPa·s at 25°C, an M / Q ratio of 0.8, and a vinyl content of 1.5 wt%. Vinyl hydroxyl silicone oil, with a viscosity of 35 mPa·s at 25°C, a vinyl content of 6.5 mol%, and a hydroxyl content of 6 mol%; Polymethylhydrosiloxane has a viscosity of 0.05 Pa·s at 25°C and a hydrogen content of 0.5 wt%.

[0046] Preparation Example 1-1 Preparation of benzotriazole silane coupling agents: 2-(2-hydroxy-5-methylphenyl)benzotriazole and 3-bromopropanol were added to a three-necked flask at a molar ratio of 1:1.05. Anhydrous potassium carbonate (1.2 times the molar amount of 2-(2-hydroxy-5-methylphenyl)benzotriazole) was added as an acid scavenger, and anhydrous DMF was added as a solvent to bring the solid content of the system to 40 wt%. The reaction was carried out at 70 °C under a nitrogen atmosphere for 6 h. After the reaction was completed, the mixture was poured into ice water and concentrated under reduced pressure to obtain the etherified product. The product was then dried to obtain the hydroxybenzotriazole intermediate. The above-mentioned hydroxybenzotriazole intermediate and propyltriethoxysilane isocyanate were added to toluene, with the molar ratio of the two controlled at 1:1.01, and the solid content of the system adjusted to 45 wt%. Under nitrogen protection, the reaction was stirred at 30 °C for 2 h to allow the hydroxyl and isocyanate groups to undergo a carbamate reaction. After the reaction was completed, the mixture was cooled to room temperature, and the toluene was removed by rotary evaporation. This product is designated as benzotriazole silane coupling agent A.

[0047] Preparation Examples 1-2 Preparation of benzotriazole silane coupling agents: 2-(2-hydroxy-5-methylphenyl)benzotriazole and propyltriethoxysilane isocyanate were added to toluene at a molar ratio of 1:1.01, and the solid content of the system was adjusted to 45 wt%. Under nitrogen protection, the mixture was stirred at 30 °C for 2 h to allow the hydroxyl groups to undergo carbamate esterification with the isocyanate groups. After the reaction was complete, the mixture was cooled to room temperature, and the toluene was removed by rotary evaporation. This product is designated as benzotriazole silane coupling agent B.

[0048] Preparation Example 2-1 Preparation of silicone oil-grafted silane coupling agents: Hydrogen-terminated polydimethylsiloxane and vinyltriethoxysilane with a number-average molecular weight of approximately 1500 were added to a three-necked flask. Toluene was added as a solvent, and the molar ratio of hydrogen-terminated polydimethylsiloxane to vinyltriethoxysilane was controlled at 1:1.01, adjusting the solid content of the system to 30 wt%. Karstedt catalyst was added to the system, with a mass fraction of 0.005 wt%. The reaction was carried out under a nitrogen atmosphere at 80 °C for 4 h with stirring. After the reaction was completed, the mixture was cooled to room temperature, and the solvent was removed by rotary evaporation. This mixture was designated as silicone oil-grafted silane coupling agent A.

[0049] Preparation Example 2-2 Preparation of silicone oil-grafted silane coupling agents: Hydrogen-terminated polydimethylsiloxane and vinyltriethoxysilane with a number average molecular weight of approximately 500 were added to a three-necked flask. Toluene was added as a solvent, and the molar ratio of hydrogen-terminated polydimethylsiloxane to vinyltriethoxysilane was controlled at 1:1.01, adjusting the solid content of the system to 30 wt%. Karstedt catalyst was added to the system, with a mass fraction of 0.005 wt%. The reaction was carried out under a nitrogen atmosphere at 80 °C for 4 h with stirring. After the reaction was completed, the mixture was cooled to room temperature, and the solvent was removed by rotary evaporation. This mixture was designated as silicone oil-grafted silane coupling agent B.

[0050] Preparation Examples 2-3 Preparation of silicone oil-grafted silane coupling agents: Hydrogen-terminated polydimethylsiloxane and vinyltriethoxysilane with a number average molecular weight of approximately 2500 were added to a three-necked flask. Toluene was added as a solvent, and the molar ratio of hydrogen-terminated polydimethylsiloxane to vinyltriethoxysilane was controlled at 1:1.01, adjusting the solid content of the system to 30 wt%. Karstedt catalyst was added to the system, with a mass fraction of 0.005 wt%. The reaction was carried out under a nitrogen atmosphere at 80 °C for 4 h with stirring. After the reaction was completed, the mixture was cooled to room temperature, and the solvent was removed by rotary evaporation. This mixture was designated as silicone oil-grafted silane coupling agent C.

[0051] Preparation Example 3-1 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 8 parts of benzotriazole silane coupling agent A were added to a three-necked flask, along with 500 parts of a 95:5 ethanol / water mixture. Mechanical stirring was then initiated to ensure uniform dispersion. The mixture was reacted at 60 °C for 3 hours to allow the benzotriazole silane coupling agent to undergo hydrolysis and condensation, grafting it onto the silica surface. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain benzotriazole-grafted silica.

[0052] 100 parts of the benzotriazole-grafted silica obtained above and 5 parts of silicone oil-grafted silane coupling agent A were added to a new reactor. A mixed solution of 500 parts of ethanol / water (volume fraction 95:5) was added, and the mixture was stirred and dispersed evenly. The reactor was then reacted at 60°C for 4 hours, allowing the silicone oil-grafted silane coupling agent to continue hydrolytic condensation and coalescence on the silica surface, forming a flexible siloxane interface layer. After the reaction was completed, the mixture was cooled to room temperature, the solid was filtered, washed successively with ethanol and deionized water, and dried at 80°C to obtain modified silica A.

[0053] Preparation Example 3-2 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 8 parts of benzotriazole silane coupling agent B were added to a three-necked flask, along with 500 parts of a 95:5 ethanol / water mixture. Mechanical stirring was then initiated to ensure uniform dispersion. The mixture was reacted at 60 °C for 3 hours to allow the benzotriazole silane coupling agent to undergo hydrolysis and condensation, grafting it onto the silica surface. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain benzotriazole-grafted silica.

[0054] 100 parts of the benzotriazole-grafted silica obtained above and 5 parts of silicone oil-grafted silane coupling agent A were added to a new reactor. 500 parts of a mixed solution of ethanol / water (volume fraction 95:5) were added, and the mixture was stirred and dispersed evenly. The reactor was then reacted at 60°C for 4 hours, allowing the silicone oil-grafted silane coupling agent to continue hydrolytic condensation and coalescence on the silica surface, forming a flexible siloxane interface layer. After the reaction was completed, the mixture was cooled to room temperature, the solid was filtered, washed successively with ethanol and deionized water, and dried at 80°C to obtain modified silica B.

[0055] Preparation Example 3-3 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 8 parts of benzotriazole silane coupling agent A were added to a three-necked flask, along with 500 parts of a 95:5 ethanol / water mixture. Mechanical stirring was then initiated to ensure uniform dispersion. The mixture was reacted at 60 °C for 3 hours to allow the benzotriazole silane coupling agent to undergo hydrolysis and condensation, grafting it onto the silica surface. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain benzotriazole-grafted silica.

[0056] 100 parts of the benzotriazole-grafted silica obtained above and 5 parts of silicone oil-grafted silane coupling agent B were added to a new reactor. 500 parts of a mixed solution of ethanol / water (volume fraction 95:5) were added, and the mixture was stirred and dispersed evenly. The reactor was then reacted at 60°C for 4 hours, allowing the silicone oil-grafted silane coupling agent to continue hydrolytic condensation and coalescence on the silica surface, forming a flexible siloxane interface layer. After the reaction was completed, the mixture was cooled to room temperature, the solid was filtered, washed successively with ethanol and deionized water, and dried at 80°C to obtain modified silica C.

[0057] Preparation Examples 3-4 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 8 parts of benzotriazole silane coupling agent A were added to a three-necked flask, along with 500 parts of a 95:5 ethanol / water mixture. Mechanical stirring was then initiated to ensure uniform dispersion. The mixture was reacted at 60 °C for 3 hours to allow the benzotriazole silane coupling agent to undergo hydrolysis and condensation, grafting it onto the silica surface. After the reaction was complete, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain benzotriazole-grafted silica.

[0058] 100 parts of the benzotriazole-grafted silica obtained above and 5 parts of silicone oil-grafted silane coupling agent C were added to a new reactor. 500 parts of a mixed solution of ethanol / water (volume fraction 95:5) were added, and the mixture was stirred and dispersed evenly. The reactor was then reacted at 60°C for 4 hours, allowing the silicone oil-grafted silane coupling agent to continue hydrolytic condensation and coalescence on the silica surface, forming a flexible siloxane interface layer. After the reaction was completed, the mixture was cooled to room temperature, the solid was filtered, washed successively with ethanol and deionized water, and dried at 80°C to obtain modified silica D.

[0059] Preparation Examples 3-5 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm, 8 parts of benzotriazole silane coupling agent A, and 5 parts of silicone oil-grafted silane coupling agent A were added to a three-necked flask. A mixed solution of ethanol / water (95:5 volume fraction) was added, and mechanical stirring was started to ensure uniform dispersion. The reaction was carried out at 60 °C for 5 h, allowing the benzotriazole silane coupling agent and the silicone oil-grafted silane coupling agent to undergo hydrolysis and condensation, and then grafted onto the surface of the silica. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain modified silica E.

[0060] Comparative Preparation Example 3-1 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 13 parts of benzotriazole silane coupling agent A were added to a three-necked flask, along with 1000 parts of a mixed solution of ethanol / water (volume fraction 95:5). Mechanical stirring was initiated to ensure uniform dispersion of the system. The reaction was carried out at 60 °C for 5 h, allowing the benzotriazole silane coupling agent to undergo hydrolysis and condensation, and then grafted onto the surface of the silica. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain modified silica F.

[0061] Comparative Preparation Example 3-2 Preparation of modified silica: 100 parts of silica with an average particle size of 15 nm and 13 parts of silicone oil-grafted silane coupling agent A were added to a three-necked flask. 1000 parts of a mixed solution of ethanol / water (95:5 volume fraction) were added, and mechanical stirring was started to ensure uniform dispersion. The reaction was carried out at 60 °C for 6 h to allow the silicone oil-grafted silane coupling agent to undergo hydrolysis and condensation, and then grafted onto the surface of the silica. After the reaction was completed, the mixture was cooled to room temperature, filtered, washed with water to remove unreacted substances and low-molecular-weight impurities, and dried at 80 °C to obtain modified silica G.

[0062] Example 1 Preparation of highly transparent silicone rubber materials: Add 100 parts of methyl vinyl phenyl silicone rubber to a mixer and start stirring. Then add 20 parts of modified silica A and 4 parts of vinyl MQ silicone resin in sequence to completely wet and evenly disperse the filler. Maintain the mixing temperature at 120°C and the mixing time at 15 minutes.

[0063] Add 5 parts polymethylhydrosiloxane and 1.2 parts vinyl hydroxyl silicone oil to the system. Continue mixing for 10 minutes to ensure it is fully compatible with the matrix.

[0064] Finally, add 0.002 parts of Karstedt platinum catalyst and continue mixing for 3 minutes to ensure uniform dispersion of the catalyst. Stop mixing and place the rubber compound in a vacuum degassing machine at 60°C for 10 minutes to degas, obtaining a transparent and uniform silicone rubber compound.

[0065] The degassed rubber compound was placed in a mold at 150°C and hot-pressed at 10MPa for 10 minutes. Then, it was vulcanized in two stages at 180°C for 2 hours to obtain a highly transparent silicone rubber material with a transparent, uniform appearance and no bubbles.

[0066] Example 2 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica B is used instead of modified silica A.

[0067] Example 3 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica C is used instead of modified silica A.

[0068] Example 4 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica D is used instead of modified silica A.

[0069] Example 5 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica E is used instead of modified silica A.

[0070] Comparative Example 1 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica F is used instead of modified silica A.

[0071] Comparative Example 2 Preparation of highly transparent silicone rubber materials: It is largely the same as Example 1, except that modified silica G is used instead of modified silica A.

[0072] Comparative Example 3 Preparation of highly transparent silicone rubber materials: Add 100 parts of methyl vinyl phenyl silicone rubber to a mixer and start stirring. Then add 20 parts of silica, 1.6 parts of benzotriazole silane coupling agent A, 1 part of silicone oil grafted silane coupling agent A and 4 parts of vinyl MQ silicone resin in sequence to completely wet and evenly disperse the filler. Maintain the mixing temperature at 120°C and the mixing time at 15 minutes.

[0073] Add 5 parts polymethylhydrosiloxane and 1.2 parts vinyl hydroxyl silicone oil to the system. Continue mixing for 10 minutes to ensure it is fully compatible with the matrix.

[0074] Finally, add 0.002 parts of Karstedt platinum catalyst and continue mixing for 3 minutes to ensure uniform dispersion of the catalyst. Stop mixing and place the rubber compound in a vacuum degassing machine at 60°C for 10 minutes to degas, obtaining a transparent and uniform silicone rubber compound.

[0075] The degassed rubber compound was placed in a mold at 150°C and hot-pressed at 10MPa for 10 minutes. Then, it was vulcanized in two stages at 180°C for 2 hours to obtain a highly transparent silicone rubber material with a transparent, uniform appearance and no bubbles.

[0076] Test section The highly transparent silicone rubber materials obtained in the above embodiments and comparative examples were cut into samples with a thickness of 2±0.1 mm and subjected to the following tests: Transmittance test: Referring to GB / T 2410-2008, the sample was placed in the optical path of the transmittance tester, and the transmittance T0 (%) was measured under visible light at a wavelength of 550nm. The results are shown in Table 1.

[0077] Transmittance retention test after photoaging: The sample was placed in a photoaging chamber, and a blue LED light source with a main peak wavelength of about 450nm was used to control the irradiance of the sample surface at 20W / m². 2The distance between the sample and the light source was kept constant, and the sample was continuously irradiated at 25℃ for 100 hours. After the irradiation, the transmittance T1 (%) after light aging was tested according to the above transmittance test method. The transmittance retention rate δ (%) after light aging was calculated as T1 / T0×100%, and the results are shown in Table 1.

[0078] Table 1

[0079] According to Table 1, the initial transmittance T0 of each embodiment is significantly higher than that of comparative examples 1 to 3, and each embodiment has a high transmittance retention rate δ after light aging, indicating that the transparent silicone rubber material provided in this application has significant advantages in terms of transparency and light aging stability. The possible reasons are as follows: In Comparative Example 1, only benzotriazole silane coupling agent was grafted onto the surface of silica. The lack of flexible siloxane segments in the interface layer to regulate the refractive index caused abrupt changes in refractive index at the local interface and the formation of light scattering points, resulting in a significant decrease in initial transmittance. In Comparative Example 2, only silicone oil grafted with silane coupling agent was grafted onto the surface of silica. Although this was beneficial for improving initial transparency, the system lacked an effective anti-photoaging structure. The free radicals generated by the silicone rubber backbone under blue light irradiation were difficult to capture in time, resulting in a significantly low transmittance retention rate. In Comparative Example 3, benzotriazole silane coupling agent and silicone oil grafted with silane coupling agent were added by physical blending, which failed to form a uniform and stable interface layer on the surface of silica. This resulted in uneven distribution of the two types of functional groups in the compound. In addition, there may be a small amount of free benzotriazole silane coupling agent in the system, which may have a certain poisoning effect on the Karstedt catalyst, making the transparency and light stability significantly lower than those in the examples.

[0080] As shown in Examples 1 and 2, the hydroxybenzotriazole structure obtained by Williamson etherification exhibits superior performance in both transparency and light retention, indicating that the molecular configuration of the benzotriazole structure significantly affects the uniformity and photostability of the interfacial layer. After etherification modification, the benzotriazole groups can be more fully spread on the surface of silica via flexible alkoxy segments, forming a more uniform and complete anti-photoaging layer, while avoiding the localized accumulation and interfacial discontinuity that may occur when unmodified benzotriazole directly contacts the interface. Therefore, the etherified benzotriazole silane coupling agent can better exert a combined effect of stabilizing transparency and inhibiting photodegradation in transparent silicone rubber systems.

[0081] As demonstrated in Examples 1, 3, and 4, the molecular weight of the polydimethylsiloxane segments in the silicone oil-grafted silane coupling agent affects both transparency and light stability. Shorter segments are less likely to form a continuous, flexible refractive index transition layer on the silica surface, resulting in lower initial transmittance; excessively long segments may cause local stacking or curling, reducing the uniformity of the interface layer and causing a slight increase in scattering. In contrast, medium-molecular-weight silicone oil segments are more suitable for constructing a uniform, flexible interface layer on the silica surface, simultaneously playing a role in refractive index matching and free radical buffering. Therefore, Example 1 exhibits superior transparency and stability.

[0082] As shown in Examples 1 and 5, the material prepared by stepwise grafting exhibits superior performance compared to the material prepared by one-pot simultaneous grafting, indicating that the reaction sequence of the two types of coupling agents has a significant impact on the interfacial layer structure. Stepwise grafting allows benzotriazole to preferentially form a dense and uniform light-stabilized layer on the surface of silica, followed by the grafting of silane coupling agents with silicone oil to construct a flexible refractive index regulating layer, thereby forming a more ordered bilayer interfacial structure. In contrast, during simultaneous grafting, the two types of coupling agents compete for the same hydrolysis condensation sites, easily leading to uneven surface distribution or incomplete local coating, resulting in lower transparency and light stability compared to Example 1.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A highly transparent silicone rubber material, characterized by, The raw materials include the following quality parts: 100 parts of methyl vinyl phenyl rubber, 10-30 parts of modified white carbon black, 3-5 parts of vinyl MQ silicone resin, 4-6 parts of polymethyl hydrogen siloxane, 1-1.5 parts of vinyl hydroxyl silicone oil, and 0.001-0.003 parts of platinum catalyst; The modified white carbon black is obtained by grafting the benzotriazole silane coupling agent and the silicone oil grafted silane coupling agent to the white carbon black; the benzotriazole silane coupling agent is obtained by urethane reaction of the hydroxy benzotriazole compound and the isocyanate silane coupling agent; and the silicone oil grafted silane coupling agent is obtained by addition reaction of the hydrogen-terminated polydimethylsiloxane and the vinyl silane coupling agent.

2. The silicone rubber material according to claim 1, characterized in that, The benzotriazole silane coupling agent is prepared by the following method: The hydroxy benzotriazole compound and the isocyanate silane coupling agent are dispersed in toluene, and reacted at 25-35℃ for 1-3h to obtain the benzotriazole silane coupling agent.

3. The silicone rubber material according to claim 2, characterized in that, The hydroxy benzotriazole compound is obtained by Williamson etherification reaction of 2-(2-hydroxy-5-methylphenyl) benzotriazole and bromine propyl alcohol.

4. The silicone rubber material according to claim 2, characterized in that, The molar ratio of the hydroxy benzotriazole compound and the isocyanate silane coupling agent is 1:1-1.02, and the solid content of the reaction system is 40wt%-50wt%.

5. The silicone rubber material according to claim 1, characterized in that, The silicone oil grafted silane coupling agent is prepared by the following method: The hydrogen-terminated polydimethylsiloxane, the vinyl silane coupling agent and the Karstedt catalyst are dispersed in toluene, and reacted at 70-90℃ for 3-5h to obtain the silicone oil grafted silane coupling agent.

6. The silicone rubber material according to claim 5, characterized in that, The number average molecular weight of the hydrogen-terminated polydimethylsiloxane is 1000-2000; the molar ratio of the hydrogen-terminated polydimethylsiloxane and the vinyl silane coupling agent is 1:1-1.02, the concentration of the Karstedt catalyst in the reaction system is 0.001wt%-0.01wt%, and the solid content of the reaction system is 20wt%-40wt%.

7. The silicone rubber material according to claim 1, characterized in that, The modified white carbon black is prepared by the following steps: S1: dispersing the white carbon black and the benzotriazole silane coupling agent in an aqueous ethanol solution, and grafting the benzotriazole silane coupling agent onto part of the surface of the white carbon black by hydrolysis and condensation to obtain benzotriazole grafted white carbon black; S2: dispersing the benzotriazole grafted white carbon black and the silicone oil grafted silane coupling agent in an aqueous ethanol solution, and grafting the silicone oil grafted silane coupling agent onto the surface of the white carbon black by hydrolysis and condensation to obtain the modified white carbon black.

8. The silicone rubber material according to claim 7, characterized in that, The modified white carbon black is prepared by the following steps: S1: dispersing 100 parts of white carbon black with an average particle size of 10-20nm and 6-10 parts of benzotriazole silane coupling agent in 400-600 parts of aqueous ethanol solution, and reacting at 50-70℃ for 2-4h to obtain benzotriazole grafted white carbon black; S2: dispersing 100 parts of benzotriazole grafted white carbon black and 4-6 parts of silicone oil grafted silane coupling agent in 400-600 parts of aqueous ethanol solution, and reacting at 50-70℃ for 3-5h to obtain the modified white carbon black.

9. The silicone rubber material according to any one of claims 1 to 8, characterized in that, The raw materials satisfy at least one of the following conditions: 1) the viscosity of the methylvinylphenyl rubber at 25℃ is 10~50Pa·s, the vinyl content is 0.1mol%~0.3mol%, the phenyl content is 4mol%~8mol%; 2) the viscosity of the vinyl MQ silicone resin at 25℃ is 5000~15000mPa·s, the value of M / Q is 0.7~0.9, the vinyl content is 0.5~2wt%; 3) the viscosity of the polymethylhydrogen siloxane at 25℃ is 0.01~0.1Pa·s, the hydrogen content is 0.1wt%~1wt%; 4) the viscosity of the vinyl hydroxyl silicone oil at 25℃ is 20~100mPa·s, the vinyl content is 6mol%~7mol%, the hydroxyl content is 5.5mol%~6.5mol%; 5) the platinum catalyst includes Karstedt catalyst.

10. A process for the preparation of a highly transparent silicone rubber material, characterized in that, Comprise: providing raw materials of the silicone rubber according to any one of claims 1~9; mixing and curing the raw materials to obtain high transparent silicone rubber material.

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