Potting glue, preparation method of potting glue and laying method of potting glue

Abstract

This invention discloses a potting compound, a method for preparing the potting compound, and a method for applying the potting compound, relating to the field of asphalt pavement maintenance technology. It includes a silicone rubber matrix comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil; hierarchical transparent silica comprising a combination of spherical nano-SiO2 and mesoporous SiO2; a silane coupling agent complex system comprising a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane; a multi-level elastic modifier comprising a combination of low-temperature elastic agents, high-temperature elastic agents, and siloxane copolymers; a temperature gradient vulcanization system comprising a combination of platinum complex catalysts and reaction inhibitors; a synergistic antireflective nanocomposite material; and a UV-A benzotriazole derivative. This invention achieves a balance between mechanical strength and optical transparency through the synergistic configuration of the silicone rubber matrix and hierarchical transparent silica.

Description

Technical Field

[0001] This invention relates to the field of asphalt pavement maintenance technology, and in particular to a sealant, a method for preparing the sealant, and a method for laying the sealant. Background Art

[0002] Asphalt pavement, as a major form of modern road construction, boasts advantages such as driving comfort, low noise, and convenient construction, and is widely used in infrastructure such as highways, urban roads, and airport runways. However, during long-term use, asphalt pavement inevitably develops various cracks and defects due to factors such as temperature changes, vehicle loads, material aging, and water damage. If these cracks are not repaired in time, they will further develop into serious defects such as potholes and network cracking, affecting the service life of the road and driving safety. Traditional crack repair mainly uses hot asphalt grouting or modified asphalt grouting techniques, but with the improvement of road maintenance standards and the development of intelligent detection technology, existing technologies have revealed many shortcomings.

[0003] First, it suffers from poor transparency and aesthetics. Traditional crack sealing materials are mostly dark or black, resulting in a noticeable color difference between the repaired surface and the original pavement, severely affecting the road's appearance, especially on scenic roads and high-grade highways.

[0004] Secondly, the elasticity and adaptability are insufficient. Existing crack sealing materials usually use a single formula, which cannot be specifically selected according to the movement characteristics of different cracks. This results in high-movement cracks being prone to cracking, while low-movement cracks suffer from material waste and excessive softness.

[0005] Finally, the interfacial bonding strength is low. Traditional repair methods mainly rely on physical interlocking, and there is a lack of effective chemical bonding between the aggregate and the grouting material, making them prone to interfacial delamination under temperature cycling and vehicle loads. Summary of the Invention

[0006] In view of the problems existing in the existing potting compounds, potting compound preparation methods and potting compound application methods, the present invention is proposed.

[0007] Therefore, the problem to be solved by this invention is to provide a potting compound with excellent transparency, multi-level elastic adjustment capability and strong interfacial bonding performance, as well as its preparation and laying method, so as to achieve seamless and smooth repair of road cracks, while establishing a precise temperature gradient construction process to ensure stable and controllable repair quality and meet the high standards of modern road maintenance.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0009] In a first aspect, embodiments of the present invention provide a potting compound with the following weight components:

[0010] Silicone rubber matrix: 90-110 parts, comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil;

[0011] Graded transparent silica: 15-25 parts, comprising a combination of spherical nano-SiO2 and mesoporous SiO2;

[0012] Silane coupling agent compound system: 0.5-2 parts, a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane;

[0013] Multi-level elastic modifier: 5-15 parts, comprising a combination of low-temperature elastic modifier, high-temperature elastic modifier and siloxane copolymer;

[0014] Temperature gradient sulfidation system: 0.1-0.8 parts, which includes a combination of platinum complex catalyst and reaction inhibitor;

[0015] Synergistic antireflective nanocomposite material: 0.2-1 part;

[0016] UV-A benzotriazole derivative: 0.1-0.5 parts;

[0017] The low-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 8000-12000;

[0018] The high-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 15,000-25,000.

[0019] As a preferred embodiment of the potting compound of the present invention, the spherical nano-SiO2 has a particle size of 15-25 nm; the mesoporous SiO2 has a particle size of 50-80 nm.

[0020] As a preferred embodiment of the potting compound of the present invention, the preparation steps of the synergistic antireflective nanocomposite material include:

[0021] Graphene oxide was dispersed in anhydrous isopropanol at a concentration of 1-3 g / L, and ultrasonically dispersed at a power density of 300-500 W / L for 3-5 hours to obtain a stable graphene oxide dispersion.

[0022] Add an L-ascorbic acid-citric acid composite reduction system to the graphene oxide dispersion, adjust the pH to 6-7, heat to 75-80℃ under an inert atmosphere, and after the reaction has proceeded for 2 hours, add 3-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane in a molar ratio of 2:1, and continue the reaction for 6-8 hours.

[0023] After the reaction is complete, continue the reaction at 75-80℃ for 2-3 hours to allow for full bonding and cross-linking of silane molecules with the surface of reduced graphene. Add tetraethyl orthosilicate and deionized water to maintain a weakly acidic pH of 5-6. Generate a nano-SiO2 coating in situ on the surface of reduced graphene using the sol-gel method. Maintain the reaction temperature at 75-80℃ for 4-6 hours, and the coating thickness is 2-8 nm.

[0024] The synergistically enhanced nanocomposite material was obtained by centrifugation, washing with anhydrous ethanol, and vacuum drying.

[0025] The beneficial effects of this preferred technical solution are as follows: the synergistic antireflective nanocomposite material adopts a unique three-layer structure of reduced graphene-silane coupling-SiO2 coating. Graphene provides thermal conductivity, the silane layer ensures interfacial compatibility, and the SiO2 coating enhances transparency, thus achieving a synergistic effect of thermal conductivity, antireflection, and enhancement.

[0026] In a preferred embodiment of the potting compound of the present invention, the weight ratio of the platinum complex catalyst to the reaction inhibitor is 1:0.5-2.

[0027] The weight ratio of the spherical nano-SiO2 to the mesoporous SiO2 is 1-2:1;

[0028] The weight ratio of γ-glycidoxypropyltrimethoxysilane to vinyltriethoxysilane is 2-4:1.

[0029] As a preferred embodiment of the potting compound of the present invention, the potting compound is classified into high-elasticity potting compound, medium-elasticity potting compound and low-elasticity potting compound according to the different proportions of low-temperature elastic agent, high-temperature elastic agent and siloxane copolymer in the multi-level elastic modifier.

[0030] The ratio of the low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the high-elasticity potting compound is 4:6:1.

[0031] The ratio of the low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the medium-elastic potting compound is 3:4:1.5;

[0032] The low-elasticity potting compound has a low-temperature elastic agent, a high-temperature elastic agent, and a siloxane copolymer in a ratio of 2:3:2.

[0033] The beneficial effects of this preferred technical solution are as follows: a three-level classification system based on the ratio of elastic modifiers is established, with the high-elasticity type adapting to large deformation cracks, the medium-elasticity type balancing performance, and the low-elasticity type providing high strength, thus realizing the matching repair of one material with multiple types.

[0034] Secondly, embodiments of the present invention provide a method for preparing a potting compound, comprising the following steps:

[0035] Vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil are mixed at a weight ratio of 3-5:1 and stirred at 60-80℃ for 30-60 minutes to obtain a silicone rubber matrix.

[0036] After mixing spherical nano-SiO2 and mesoporous SiO2, a silane coupling agent complex system was added for surface treatment, and the mixture was reacted at 80-100℃ for 1-2 hours to obtain modified hierarchical transparent silica.

[0037] The silicone rubber matrix was mixed with modified graded transparent silica, and a multi-grade elastic modifier was added. The mixture was stirred and mixed evenly at room temperature.

[0038] The synergistic antireflective nanocomposite material and the UV-A benzotriazole derivative were added sequentially and stirred until evenly dispersed.

[0039] Finally, the temperature gradient vulcanization system is added, and after rapid stirring and uniform mixing, the mixture is degassed under vacuum to obtain the potting compound.

[0040] In a preferred embodiment of the preparation method of the potting compound of the present invention, the vinyl-terminated polydimethylsiloxane has a viscosity of 1000-5000 mPa·s, and the hydrogen content of the hydrogen-containing silicone oil is 0.15-0.25%.

[0041] The synergistic antireflective nanocomposite material is dispersed using ultrasound.

[0042] The degassing treatment is performed at a pressure of -0.08 to -0.1 MPa for 5 to 15 minutes.

[0043] Thirdly, embodiments of the present invention provide a method for applying potting compound, comprising the following steps:

[0044] For the cracks in the road surface to be repaired, collect information on crack movement, aggregate color, and the gradation of the original asphalt mixture.

[0045] Pre-treatment of road surface cracks by cleaning out contaminants, expansion and grooving of cracks using a grooving machine, and local heating treatment of the grooved cracks using heating equipment at a temperature of 170-190℃.

[0046] The application type of the sealant is determined according to the amount of movement of the road surface crack. When the amount of movement of the crack is greater than or equal to 6 mm, a high-elastic sealant is used; when the amount of movement of the crack is 2-6 mm, a medium-elastic sealant is used; when the amount of movement of the crack is less than or equal to 2 mm, a low-elastic sealant is used. The sealant is injected into the road surface crack, and the filling height does not exceed 3 mm of the original road surface elevation.

[0047] Based on the aggregate color information, the type of aggregate to be spread is determined by matching in the aggregate color database. Based on the gradation information of the original asphalt mixture, the particle size range of the aggregate to be spread is selected. The selected aggregate is then evenly spread onto the surface of the sealant until it is completely covered.

[0048] Use a road roller to repeatedly compact and spread the aggregate, with at least 20 compaction cycles.

[0049] As a preferred embodiment of the potting compound application method of the present invention, the spreading aggregate undergoes surface modification treatment, and a nanoscale micro-pit structure is formed on the surface of the aggregate by plasma bombardment. The micro-pit depth is 50-200 nm and the density is 10. 5 -10 6 pcs / mm 2 ;

[0050] The micro-pits are pre-filled with thermally stable siloxane oligomers.

[0051] When the aggregate is spread and compacted, a gradient cross-linked layer with a thickness of 2-5 μm is formed at the aggregate-grouting adhesive interface.

[0052] The beneficial effects of this preferred technical solution are as follows: by creating nano-anchor points through plasma modification and pre-filling them with compatible oligomers, the traditional physical intercalation is upgraded to molecular-level chemical bonding, thereby improving the interfacial bonding strength.

[0053] As a preferred embodiment of the method for laying the potting compound according to the present invention, wherein: during the reciprocating rolling and spreading of aggregates, the rolling temperature in the first stage is 60-80℃, and the rolling is performed 5-8 times to preheat the aggregates and potting compound.

[0054] The second stage of compaction is carried out at a temperature of 100-120℃, with 8-12 compactions.

[0055] The third stage of compaction involves a temperature of 120-140℃ and 5-8 compactions.

[0056] Set a 2-3 minute temperature equilibration time between each stage, and set the temperature deviation within ±5℃.

[0057] The beneficial effects of this preferred technical solution are as follows: by adopting a three-stage incremental temperature-controlled rolling process, an orderly reaction process from preheating to activation to crosslinking is realized, which ensures the uniform formation of the gradient crosslinking layer and the stability of the repair quality.

[0058] The beneficial effects of this invention are:

[0059] By synergistically configuring a silicone rubber matrix with graded transparent silica, a balance between mechanical strength and optical transparency is achieved. The fluidity provided by spherical nano-SiO2 and the light scattering suppression effect of mesoporous SiO2 mutually enhance each other, enabling the potting compound to achieve high transparency while maintaining excellent processing performance. This solves the problem of significant color difference in traditional repair materials. Furthermore, the electron cloud resonance effect of the reduced graphene in the synergistic antireflective nanocomposite material, combined with the molecular orientation effect of the silane coupling layer, forms a gradient refractive index match under the optical matching of the nano-SiO2 coating. This effect allows the material to achieve optical performance matching according to ambient lighting conditions, resulting in a seamless visual integration with the original pavement.

[0060] The three-stage incremental temperature-controlled compaction process achieves synergistic regulation of reaction kinetics and stress release. The progressive temperature treatment of preheating-activation-crosslinking not only ensures the orderly progress of the chemical reaction but also produces a stress homogenization effect. The molecular chain rearrangement and crosslinking network construction at each temperature stage work together to eliminate thermal stress concentration, enabling the repaired area to obtain a residual stress distribution that matches the original pavement, achieving seamless smooth repair. Specifically, the first stage is used to activate the end-group reaction of siloxane oligomers on the aggregate surface, the second stage is used to promote diffusion and interpenetration reactions, and the third stage is used to complete the construction of the gradient crosslinking network. Detailed Implementation

[0061] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, a detailed description is provided below in conjunction with specific embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0062] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0063] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0064] Example 1 discloses a potting compound comprising the following components by weight:

[0065] Silicone rubber matrix: 90 parts, comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil;

[0066] Graded transparent silica: 15 parts, comprising a combination of spherical nano-SiO2 and mesoporous SiO2, wherein the particle size of the spherical nano-SiO2 is 15 nm and the particle size of the mesoporous SiO2 is 50 nm;

[0067] Silane coupling agent compound system: 0.5 parts, a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane;

[0068] Multi-level elastic modifier: 5 parts, comprising a combination of low-temperature elastic modifier, high-temperature elastic modifier and siloxane copolymer;

[0069] Temperature gradient sulfidation system: 0.1 parts, which includes a combination of platinum complex catalyst and reaction inhibitor. In this embodiment, the platinum complex catalyst is platinum-divinyltetramethyldisiloxane complex, and the reaction inhibitor is 1-ethynyl-1-cyclohexanol.

[0070] Synergistic antireflective nanocomposite material: 0.2 parts;

[0071] UV-A benzotriazole derivative: 0.1 parts;

[0072] The low-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 8000;

[0073] The high-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 15,000.

[0074] It is important to know that the preparation steps of the synergistic antireflective nanocomposite material include:

[0075] Graphene oxide was dispersed in anhydrous isopropanol at a concentration of 1 g / L and ultrasonically dispersed at a power density of 300 W / L for 3 hours to obtain a stable graphene oxide dispersion.

[0076] L-ascorbic acid-citric acid composite reduction system was added to the graphene oxide dispersion, the pH was adjusted to 6, the temperature was raised to 75°C under an inert atmosphere, and after the reaction proceeded for 2 hours, 3-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane were added in a molar ratio of 2:1, and the reaction was continued for 6 hours.

[0077] After the reaction was completed, the reaction was continued at 75°C for 2 hours to allow for full bonding and cross-linking of silane molecules with the surface of reduced graphene. Tetraethyl orthosilicate and deionized water were added dropwise to maintain a weakly acidic pH of 5. A nano-SiO2 coating was generated in situ on the surface of reduced graphene by the sol-gel method. The reaction temperature was maintained at 75°C for 4 hours, and the coating thickness was 2 nm.

[0078] Synergistically enhanced nanocomposite materials were obtained by centrifugation, washing with anhydrous ethanol, and vacuum drying.

[0079] The weight ratio of platinum complex catalyst to reaction inhibitor is 1:0.5;

[0080] The weight ratio of spherical nano-SiO2 to mesoporous SiO2 is 1:1;

[0081] The weight ratio of γ-glycidoxypropyltrimethoxysilane to vinyltriethoxysilane is 2:1.

[0082] Example 2 discloses a potting compound comprising the following components by weight:

[0083] Silicone rubber matrix: 100 parts, comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil;

[0084] Graded transparent silica: 20 parts, comprising a combination of spherical nano-SiO2 and mesoporous SiO2, wherein the particle size of the spherical nano-SiO2 is 20 nm and the particle size of the mesoporous SiO2 is 65 nm;

[0085] Silane coupling agent compound system: 1 part, a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane;

[0086] Multi-level elastic modifier: 10 parts, comprising a combination of low-temperature elastic modifier, high-temperature elastic modifier and siloxane copolymer;

[0087] Temperature gradient sulfidation system: 0.5 parts, which includes a combination of platinum complex catalyst and reaction inhibitor;

[0088] Synergistically antireflective nanocomposite material: 0.5 parts;

[0089] UV-A benzotriazole derivative: 0.3 parts;

[0090] The low-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 10,000.

[0091] The high-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 20,000.

[0092] It is important to know that the preparation steps of the synergistic antireflective nanocomposite material include:

[0093] Graphene oxide was dispersed in anhydrous isopropanol at a concentration of 2 g / L and ultrasonically dispersed at a power density of 400 W / L for 4 hours to obtain a stable graphene oxide dispersion.

[0094] L-ascorbic acid-citric acid composite reduction system was added to the graphene oxide dispersion, the pH was adjusted to 6, the temperature was raised to 80°C under an inert atmosphere, and after the reaction was carried out for 2 hours, 3-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane were added in a molar ratio of 2:1, and the reaction was continued for 7 hours.

[0095] After the reaction was completed, the reaction was continued at 80℃ for 2 hours to allow for full bonding and cross-linking of silane molecules with the surface of reduced graphene. Tetraethyl orthosilicate and deionized water were added dropwise to maintain a weakly acidic pH of 6. A nano-SiO2 coating was generated in situ on the surface of reduced graphene by the sol-gel method. The reaction temperature was maintained at 80℃ for 5 hours, and the coating thickness was 6 nm.

[0096] Synergistically enhanced nanocomposite materials were obtained by centrifugation, washing with anhydrous ethanol, and vacuum drying.

[0097] The weight ratio of platinum complex catalyst to reaction inhibitor is 1:1;

[0098] The weight ratio of spherical nano-SiO2 to mesoporous SiO2 is 2:1;

[0099] The weight ratio of γ-glycidoxypropyltrimethoxysilane to vinyltriethoxysilane is 3:1.

[0100] Example 3 discloses a potting compound comprising the following components by weight:

[0101] Silicone rubber matrix: 110 parts, comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil;

[0102] Graded transparent silica: 25 parts, comprising a combination of spherical nano-SiO2 and mesoporous SiO2, wherein the particle size of the spherical nano-SiO2 is 25 nm and the particle size of the mesoporous SiO2 is 80 nm;

[0103] Silane coupling agent compound system: 2 parts, a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane;

[0104] Multi-level elastic modifier: 15 parts, comprising a combination of low-temperature elastic modifier, high-temperature elastic modifier and siloxane copolymer;

[0105] Temperature gradient sulfidation system: 0.8 parts, which includes a combination of platinum complex catalyst and reaction inhibitor;

[0106] Synergistic antireflective nanocomposite material: 1 part;

[0107] UV-A benzotriazole derivative: 0.5 parts;

[0108] The low-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 12,000.

[0109] The high-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 25,000.

[0110] It is important to know that the preparation steps of the synergistic antireflective nanocomposite material include:

[0111] Graphene oxide was dispersed in anhydrous isopropanol at a concentration of 3 g / L, and ultrasonically dispersed at a power density of 500 W / L for 5 hours to obtain a stable graphene oxide dispersion.

[0112] L-ascorbic acid-citric acid composite reduction system was added to the graphene oxide dispersion, the pH was adjusted to 7, and the temperature was raised to 80°C under an inert atmosphere. After the reaction proceeded for 2 hours, 3-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane were added in a molar ratio of 2:1, and the reaction was continued for 8 hours.

[0113] After the reaction was completed, the reaction was continued at 80℃ for 2 hours to allow for full bonding and cross-linking of silane molecules with the surface of reduced graphene. Tetraethyl orthosilicate and deionized water were added dropwise to maintain a weakly acidic pH of 6. A nano-SiO2 coating was generated in situ on the surface of reduced graphene by the sol-gel method. The reaction temperature was maintained at 80℃ for 6 hours, and the coating thickness was 8nm.

[0114] Synergistically enhanced nanocomposite materials were obtained by centrifugation, washing with anhydrous ethanol, and vacuum drying.

[0115] The weight ratio of platinum complex catalyst to reaction inhibitor is 1:2;

[0116] The weight ratio of spherical nano-SiO2 to mesoporous SiO2 is 2:1;

[0117] The weight ratio of γ-glycidoxypropyltrimethoxysilane to vinyltriethoxysilane is 4:1.

[0118] Comparative Example 1, compared to Example 2, removed mesoporous SiO2 and used only 20nm spherical nano-SiO2, while the other components were the same as in Example 2.

[0119] Table 1: Performance Comparison Table of Example 2 and Comparative Example 1

[0120]

[0121] Table 1 shows that the number of agglomerates was counted using microscopic observation in the dispersion performance test, which is a direct method for evaluating the dispersion effect of nanofillers. In Example 2, the number of agglomerates was controlled to be less than 5 per field of view, while in Comparative Example 1 it reached 12-15 per field of view. This indicates that when using 20nm spherical nano-SiO2 alone, secondary agglomeration is easily formed due to the strong van der Waals forces between particles and the large specific surface area. In Example 2, the addition of 65nm mesoporous SiO2 acted as a "dispersing aid," forming physical isolation between nanoparticles and effectively inhibiting agglomeration.

[0122] In terms of mechanical properties, the elongation at break test showed that Example 2 reached 385%, which was 20% higher than the 320% of Comparative Example 1. This result verifies the advantages of the hierarchical filler design. The addition of mesoporous SiO2 not only did not sacrifice the flexibility of the material, but also reduced stress concentration points by improving the filler dispersion state, enabling the material to withstand greater deformation without fracture during tensile testing.

[0123] In the verification of optical performance advantages, the optical performance of a 2mm thick sample was tested using the GB / T2410 standard. Example 2 achieved a transmittance of 85.2%, an 8.4% improvement compared to Comparative Example 1's 78.6%, and its haze decreased from 6.9% to 3.8%, representing a 45% improvement. This difference demonstrates the effectiveness of the hierarchical transparent silica design. The addition of mesoporous SiO2 reduces light scattering by decreasing the aggregation of nano-SiO2, while its own porous structure, under appropriate refractive index matching, reduces interface reflection, thereby achieving higher transparency and lower haze.

[0124] These test results demonstrate that Example 2, by introducing 65nm mesoporous SiO2 to construct a hierarchical filler system, successfully solved the problems of poor dispersibility caused by single nano-SiO2, improving optical properties and process stability while maintaining good mechanical properties. This synergistic effect verifies the technical rationality of the hierarchical transparent silica design and provides an effective technical path for the development of high-performance potting compounds.

[0125] Comparative Example 2, compared to Example 2, removed the synergistic antireflective nanocomposite material, while the other components were the same as in Example 2.

[0126] Table 2: Performance Comparison Table of Example 2 and Comparative Example 2

[0127]

[0128] Table 2 shows that, in terms of mechanical properties, the tensile strength of Example 2 reached 6.8 MPa, a 15% increase compared to 5.9 MPa of Comparative Example 2, and the tear strength increased further from 24.8 kN / m to 28.5 kN / m, a 15% increase. This indicates that the reduced graphene in the synergistically antireflective nanocomposite material played an effective reinforcing role. Simultaneously, the compression set decreased from 22.3% to 18.5%, and the resilience increased from 47% to 52%, indicating that the material's elastic recovery ability was improved, allowing it to better maintain shape stability during long-term use.

[0129] Among the improvements in optical performance, the transmittance increased from 81.7% to 85.2%, which is significant for potting applications requiring transparency. More importantly, the refractive index changed; the refractive index of Example 2 was 1.410, lower than that of Comparative Example 2 (1.415), and closer to the refractive index of the silicone rubber matrix. This matching helps reduce interfacial light scattering and improve overall transparency.

[0130] In terms of aging resistance, after 72 hours of UV irradiation at a wavelength of 340 nm, the strength retention rate of Example 2 reached 92%, while that of Comparative Example 2 was only 86%. This indicates that the synergistic antireflective nanocomposite material effectively improves the material's UV resistance, which is of great value for applications in outdoor or high-radiation environments.

[0131] Comparative Example 3: In a temperature gradient sulfidation system, only a platinum complex catalyst was used, and reaction inhibitors were removed. Other components were the same as in Example 2.

[0132] Table 3: Performance Comparison Table of Example 2 and Comparative Example 3

[0133]

[0134] Table 3 shows that in the vulcanization reaction kinetics, Comparative Example 3, due to the removal of the reaction inhibitor, experienced a dramatic reduction in scorch time from 3.8 minutes to 1.5 minutes, a decrease of 61%, and vulcanization time from 8.5 minutes to 5.2 minutes, resulting in a 39% increase in vulcanization rate. While this excessively rapid reaction superficially improved production efficiency, it actually posed significant challenges to process control. Example 2, by adding a reaction inhibitor, controlled the vulcanization reaction within a reasonable rate range, providing a sufficient process window for actual production operations.

[0135] In terms of product quality uniformity, Example 2 showed a uniformity of only 3.2%, while Comparative Example 3 showed a uniformity of 8.7%, a difference of nearly three times. The coefficient of variation for hardness also deteriorated from 2.8% to 7.4%, an increase of 2.6 times. This significant increase in the coefficient of variation indicates that rapid vulcanization without reaction inhibitors led to an uneven distribution of the cross-linked network, resulting in significant performance differences in different parts of the product. In practical applications, this could become stress concentration points, affecting the long-term reliability of the product.

[0136] In terms of overall mechanical properties, although the tensile strength of Comparative Example 3 decreased slightly after rapid vulcanization (from 6.8 MPa to 6.2 MPa), more importantly, the elongation at break decreased from 385% to 340%, indicating that the toughness of the material was affected. Rapid and uncontrollable vulcanization reactions easily lead to excessive cross-linking, making the material brittle and losing the flexibility that silicone rubber should have.

[0137] Example 4 provides a multi-stage elastic modifier. Based on the different proportions of low-temperature elastic agent, high-temperature elastic agent and siloxane copolymer in the multi-stage elastic modifier, the potting compound is divided into high-elasticity potting compound, medium-elasticity potting compound and low-elasticity potting compound.

[0138] The ratio of low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the high-elasticity potting compound is 4:6:1; the ratio of low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the medium-elasticity potting compound is 3:4:1.5; and the ratio of low-elasticity potting compound is 2:3:2.

[0139] Different formulations allow for the selection of appropriate performance levels based on actual needs, avoiding a "one-size-fits-all" design. For applications that do not require high elasticity, a low-elasticity formulation can be selected, reducing the amount of elastic agent used while meeting usage requirements and achieving cost control.

[0140] Example 5 provides a method for preparing a potting compound, comprising the following steps:

[0141] S1. Mix vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil in a weight ratio of 3:1, and stir at 60°C for 30 minutes to obtain a silicone rubber matrix;

[0142] The viscosity of the vinyl-terminated polydimethylsiloxane is 1000 mPa·s, and the hydrogen content of the hydrogen-containing silicone oil is 0.15%.

[0143] S2. After mixing spherical nano-SiO2 and mesoporous SiO2, a silane coupling agent complex system was added for surface treatment. The mixture was reacted at 80°C for 1 hour to obtain modified hierarchical transparent silica.

[0144] S3. Mix the silicone rubber matrix with the modified graded transparent silica, add the multi-grade elastic modifier, and stir until uniform at room temperature.

[0145] S4. Add the synergistically enhanced nanocomposite material and UV-A benzotriazole derivative in sequence, stir and disperse evenly, and then use ultrasonic dispersion.

[0146] S5. Finally, add the temperature gradient vulcanization system, stir quickly and mix evenly, and then degas under vacuum to obtain the potting compound. The degassing pressure is -0.08MPa and the time is 5 minutes.

[0147] Example 6 provides a method for preparing a potting compound, comprising the following steps:

[0148] S1. Mix vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil at a weight ratio of 5:1, and stir at 80°C for 60 minutes to obtain a silicone rubber matrix;

[0149] The vinyl-terminated polydimethylsiloxane has a viscosity of 5000 mPa·s, and the hydrogen content of the hydrogen-containing silicone oil is 0.25%.

[0150] S2. After mixing spherical nano-SiO2 and mesoporous SiO2, a silane coupling agent complex system was added for surface treatment. The mixture was reacted at 100°C for 2 hours to obtain modified hierarchical transparent silica.

[0151] S3. Mix the silicone rubber matrix with the modified graded transparent silica, add the multi-grade elastic modifier, and stir until uniform at room temperature.

[0152] S4. Add the synergistically enhanced nanocomposite material and UV-A benzotriazole derivative in sequence, stir and disperse evenly, and then use ultrasonic dispersion.

[0153] S5. Finally, add the temperature gradient vulcanization system, stir quickly and mix evenly, and then degas under vacuum to obtain the potting compound. The degassing treatment pressure is -0.1MPa and the time is 15 minutes.

[0154] Example 7 provides a method for applying potting compound, comprising the following steps:

[0155] A1. For the cracks in the road surface to be repaired, collect information on crack movement, aggregate color, and the gradation of the original asphalt mixture.

[0156] It is important to know that crack movement is the maximum displacement (mm) of a pavement crack within a year, provided by historical maintenance data from the highway management agency;

[0157] Aggregate color information refers to the hue, brightness, and saturation of aggregates near cracks;

[0158] The asphalt mixture gradation information refers to the asphalt mixture gradation type of the original pavement where the crack is located.

[0159] A2. Carry out pretreatment of dirt cleaning for road surface cracks, use a grooving machine to expand and groove the cracks, and use heating equipment to locally heat the grooved cracks at a temperature of 170-190℃.

[0160] In the process of widening and grooving cracks, the depth-to-width ratio of the crack groove is 1:1-2.

[0161] A3. Determine the application type of the sealant based on the amount of movement of the road surface crack. When the amount of movement of the crack is greater than or equal to 6mm, use a high-elastic sealant; when the amount of movement of the crack is 2-6mm, use a medium-elastic sealant; when the amount of movement of the crack is less than or equal to 2mm, use a low-elastic sealant. Inject the sealant into the road surface crack, and the filling height shall not exceed 3mm of the original road surface elevation.

[0162] A4. Based on the aggregate color information, match the aggregate color database to determine the type of aggregate to be spread. Select the particle size range of the aggregate to be spread based on the gradation information of the original pavement asphalt mixture. Spread the selected aggregate evenly onto the surface of the sealant until it is completely covered.

[0163] It is important to know that the aggregate color database contains the hue, lightness, and saturation of road aggregates.

[0164] The particle size range of the spread aggregate is shown in Table 4;

[0165] Table 4: Particle size range and mass percentage of spread aggregate

[0166]

[0167] In this embodiment, a seamless smooth repair effect is achieved for transverse cracks in the asphalt pavement of a highway in a certain province of my country. According to the historical maintenance data of this highway, the movement of the transverse crack is 6.89 mm; the hue, brightness, and saturation of the aggregate near the crack are shown in Table 4; the pavement aggregate type is AC-20.

[0168] In response to the actual situation of the transverse crack, pre-treatment by cleaning the contaminants inside the crack was carried out. Based on the actual survey results, the depth-to-width ratio of the transverse crack was 1:1.5. A liquefied gas torch was used to locally heat the crack to a temperature of 180℃. Based on the crack's movement, a high-elasticity sealant was used to fill the transverse crack. According to the pavement aggregate color information, the optimal aggregate type matched from the aggregate color database was diabase, and the aggregate particle size range for spreading is shown in Table 5.

[0169] Table 5: Particle Size Range of Spread Aggregates

[0170]

[0171] A5. Use a road roller to repeatedly compact and spread the aggregate, with a compaction frequency of no less than 20 times.

[0172] The spread aggregate undergoes surface modification treatment, which involves plasma bombardment to create nanoscale micro-pit structures on the aggregate surface. The depth of these micro-pits is 50-200 nm, and the density is 10. 5 -10 6 pcs / mm 2 ;

[0173] The micro-pits are pre-filled with thermally stable siloxane oligomers.

[0174] When the aggregate is spread and compacted, a gradient cross-linked layer with a thickness of 2-5 μm is formed at the aggregate-grouting adhesive interface.

[0175] In the embodiments of this application, when reciprocatingly rolling and spreading aggregates, the first stage rolling temperature is 60-80℃, preferably 70℃, and rolling is performed 5-8 times to preheat the aggregates and the potting compound.

[0176] The second stage of compaction temperature is 100-120℃, preferably 110℃, and compaction is performed 8-12 times.

[0177] The third stage of compaction temperature is 120-140℃, preferably 130℃, and compaction is performed 5-8 times.

[0178] Set a 2-3 minute temperature equilibration time between each stage, and set the temperature deviation within ±5℃.

[0179] Finally, using a 3m straightedge, a road testing instrument, the bidirectional smoothness of the repaired crack was measured along the longitudinal and transverse directions of the road surface. The bidirectional smoothness... The measurement calculation formula is expressed as follows:

[0180] ;

[0181] In the formula, The maximum gap along the crack direction. This represents the maximum gap perpendicular to the crack direction.

[0182] Preferably, the bidirectional flatness measurement result should not exceed 1cm.

[0183] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A potting compound, characterized in that: Includes the following components by weight: Silicone rubber matrix: 90-110 parts, comprising a combination of vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil; Graded transparent silica: 15-25 parts, comprising a combination of spherical nano-SiO2 and mesoporous SiO2; Silane coupling agent compound system: 0.5-2 parts, a combination of γ-glycidoxypropyltrimethoxysilane and vinyltriethoxysilane; Multi-level elastic modifier: 5-15 parts, comprising a combination of low-temperature elastic modifier, high-temperature elastic modifier and siloxane copolymer; Temperature gradient sulfidation system: 0.1-0.8 parts, which includes a combination of platinum complex catalyst and reaction inhibitor; Synergistic antireflective nanocomposite material: 0.2-1 part; UV-A benzotriazole derivative: 0.1-0.5 parts; The low-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 8000-12000; The high-temperature elastic agent is a vinyl-terminated polysiloxane with a molecular weight of 15,000-25,000. The spherical nano-SiO2 has a particle size of 15-25 nm; The mesoporous SiO2 has a particle size of 50-80 nm; The preparation steps of the synergistic antireflective nanocomposite material include: Graphene oxide was dispersed in anhydrous isopropanol at a concentration of 1-3 g / L, and ultrasonically dispersed at a power density of 300-500 W / L for 3-5 hours to obtain a stable graphene oxide dispersion. Add an L-ascorbic acid-citric acid composite reduction system to the graphene oxide dispersion, adjust the pH to 6-7, heat to 75-80℃ under an inert atmosphere, and after the reaction has proceeded for 2 hours, add 3-aminopropyltriethoxysilane and γ-glycidoxypropyltrimethoxysilane in a molar ratio of 2:1, and continue the reaction for 6-8 hours. After the reaction is complete, continue the reaction at 75-80℃ for 2-3 hours to allow for full bonding and cross-linking of silane molecules with the surface of reduced graphene. Add tetraethyl orthosilicate and deionized water to maintain a weakly acidic pH of 5-6. Generate a nano-SiO2 coating in situ on the surface of reduced graphene using the sol-gel method. Maintain the reaction temperature at 75-80℃ for 4-6 hours, and the coating thickness is 2-8 nm. The synergistically enhanced nanocomposite material was obtained by centrifugation, washing with anhydrous ethanol, and vacuum drying. The weight ratio of the platinum complex catalyst to the reaction inhibitor is 1:0.5-2; The weight ratio of the spherical nano-SiO2 to the mesoporous SiO2 is 1-2:

1.

2. The potting compound as described in claim 1, characterized in that: The weight ratio of γ-glycidoxypropyltrimethoxysilane to vinyltriethoxysilane is 2-4:

1.

3. The potting compound as described in claim 2, characterized in that: Based on the different proportions of low-temperature elastic agent, high-temperature elastic agent and siloxane copolymer in the multi-level elastic modifier, the potting compound is classified into high-elasticity potting compound, medium-elasticity potting compound and low-elasticity potting compound. The ratio of the low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the high-elasticity potting compound is 4:6:

1. The ratio of the low-temperature elastic agent, high-temperature elastic agent, and siloxane copolymer in the medium-elastic potting compound is 3:4:1.5; The low-elasticity potting compound has a low-temperature elastic agent, a high-temperature elastic agent, and a siloxane copolymer in a ratio of 2:3:

2.

4. A method for preparing the potting compound as described in any one of claims 1-3, characterized in that: Includes the following steps: Vinyl-terminated polydimethylsiloxane and hydrogen-containing silicone oil are mixed at a weight ratio of 3-5:1 and stirred at 60-80℃ for 30-60 minutes to obtain a silicone rubber matrix. After mixing spherical nano-SiO2 and mesoporous SiO2, a silane coupling agent complex system was added for surface treatment, and the mixture was reacted at 80-100℃ for 1-2 hours to obtain modified hierarchical transparent silica. The silicone rubber matrix was mixed with modified graded transparent silica, and a multi-level elastic modifier was added. The mixture was stirred and mixed evenly at room temperature. The synergistic antireflective nanocomposite material and the UV-A benzotriazole derivative were added sequentially and stirred until evenly dispersed. Finally, the temperature gradient vulcanization system is added, and after rapid stirring and uniform mixing, the mixture is degassed under vacuum to obtain the potting compound.

5. The method for preparing the potting compound as described in claim 4, characterized in that: The viscosity of the vinyl-terminated polydimethylsiloxane is 1000-5000 mPa·s, and the hydrogen content of the hydrogen-containing silicone oil is 0.15-0.25%. The synergistic antireflective nanocomposite material is dispersed using ultrasound. The degassing treatment is performed at a pressure of -0.08 to -0.1 MPa for 5 to 15 minutes.

6. A method for applying the potting compound as described in claim 3, characterized in that: Includes the following steps: For the cracks in the road surface to be repaired, collect information on crack movement, aggregate color, and the gradation of the original asphalt mixture. Pre-treatment of road surface cracks by cleaning out contaminants, expansion and grooving of cracks using a grooving machine, and local heating treatment of the grooved cracks using heating equipment at a temperature of 170-190℃. The application type of the sealant is determined according to the amount of movement of the road surface crack. When the amount of movement of the crack is greater than or equal to 6 mm, a high-elastic sealant is used; when the amount of movement of the crack is 2-6 mm, a medium-elastic sealant is used; when the amount of movement of the crack is less than or equal to 2 mm, a low-elastic sealant is used. The sealant is injected into the road surface crack, and the filling height does not exceed 3 mm of the original road surface elevation. Based on the aggregate color information, the type of aggregate to be spread is determined by matching in the aggregate color database. Based on the gradation information of the original asphalt mixture, the particle size range of the aggregate to be spread is selected. The selected aggregate is then evenly spread onto the surface of the sealant until it is completely covered. Use a road roller to repeatedly compact and spread the aggregate, with at least 20 compaction cycles.

7. The method for applying potting compound as described in claim 6, characterized in that: The spread aggregate undergoes surface modification treatment, where plasma bombardment forms nanoscale micro-pit structures on the aggregate surface. The depth of the micro-pits is 50-200 nm, and the density is 10. 5 -10 6 pcs / mm 2 ; The micro-pits are pre-filled with thermally stable siloxane oligomers. When the aggregate is spread and compacted, a gradient cross-linked layer with a thickness of 2-5 μm is formed at the aggregate-grouting adhesive interface.

8. The method for applying potting compound as described in claim 7, characterized in that: During the reciprocating rolling and spreading of aggregates, the first stage rolling temperature is 60-80℃, and the rolling is performed 5-8 times to preheat the aggregates and the potting compound. The second stage of compaction is carried out at a temperature of 100-120℃, with 8-12 compactions. The third stage of compaction involves a temperature of 120-140℃ and 5-8 compactions. Set a 2-3 minute temperature equilibration time between each stage, and set the temperature deviation within ±5℃.

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