Environment-friendly low-viscosity insulating silicone rubber coating for preventing bird damage as well as preparation method and application thereof

Abstract

The invention relates to the field of protective materials for electrical equipment, and discloses an environment-friendly low-viscosity insulating silicone rubber coating for preventing bird damage. Raw materials for preparing the environment-friendly low-viscosity insulating silicone rubber coating for preventing bird damage comprise methyl vinyl silicone rubber, nano aluminum oxide, modified fumed silica, a bird repellent, a platinum catalyst, a silane coupling agent, water and a bio-based plasticizer. Through matrix modification, an environment-friendly bird repelling system and nanofiller optimization, the problems of long curing time, insufficient environment friendliness, insufficient insulating strength and the like of an existing bird damage prevention coating are solved, and an innovative breakthrough of a technical route is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power equipment protection materials, in particular to an environment-friendly low-viscosity insulating silicone rubber coating for bird damage prevention and a preparation method and application thereof. BACKGROUND

[0002] Bird damage prevention has become one of the key tasks for preventing and treating power transmission and distribution line faults in some provinces. Large birds such as herons, crows and magpies excrete feces above the towers, causing local gap short circuits; and the branches and iron wires used by magpies and other birds to build nests may fall on the tower lines, causing fault tripping. Essentially, bird-related faults are caused by the reduction of tower gap insulation distance due to bird nesting, staying and bird-related foreign objects, resulting in tower air gap discharge breakdown. Traditional bird prevention devices (such as bird spikes and bird covers) have problems such as complex installation and easy aging, and existing bird prevention measures also have defects due to the regional and seasonal characteristics of bird activities, and cannot fundamentally solve the problem of bird damage faults. It is urgent to improve the bird damage prevention level of power transmission and distribution lines from the perspective of intrinsic safety of power transmission and distribution lines and reduce the risk of bird damage tripping.

[0003] Chinese patent application CN118546588A discloses a multifunctional insulating coating for high-voltage power transmission lines, which comprises the following components by weight ratio: epoxy resin 30-35%, polyester resin 25-30%, pigment 10-15%, filler 6-10%, solvent 25%, and the rest is functional additives; the functional additives include ultraviolet resistance agent, antioxidant and flame retardant; the beneficial effects are: the multifunctional insulating coating for high-voltage power transmission lines prolongs the service life of the coating and maintains the stability of its performance by absorbing, reflecting or scattering ultraviolet radiation to protect the coating from ultraviolet damage, prevents the organic components in the coating from undergoing oxidation reaction under the action of oxygen by adding an antioxidant to maintain the performance and stability of the coating, and improves the flame retardant performance of the coating by delaying or preventing the spread of fire through a series of physical and chemical actions when the coating encounters a fire source. However, this coating lacks consideration of bird-related foreign objects and evaluation of insulation performance, and the bird damage prevention level is limited.

[0004] Chinese patent application CN109897533A discloses an RTV bird repellent coating and a preparation method thereof, comprising the following raw materials by weight: modified polysiloxane 5566 parts, bird repellent powder 3.24.6 parts, silica gel 35.843.4 parts, fumed white carbon black 2128.5 parts, flame retardant 3647.2 parts, nano active metal oxide 2.53.4 parts, pigment 4.26.3 parts, crosslinking agent 5.87.9 parts, coupling agent 1.11.85 parts, catalyst 0.120.26 parts, polyamino siloxane 46.5 parts and solvent 165173 parts. The finished product of the application can effectively prevent birds from pecking the composite insulator umbrella skirt, protect the integrity of the composite insulator structure, prevent flashover phenomenon caused by damage to the composite insulator, while meeting the requirements of related electrical performance and physical and chemical properties, and ensuring the safe and stable operation of the power transmission line. However, the bird repellent coating contains chemical bird repellent and organic solvent, and the environmental protection is insufficient. SUMMARY

[0005] The purpose of the present application is to overcome the above-mentioned problems existing in the prior art, provide an environmentally friendly low-viscosity insulating silicone rubber coating for bird damage prevention and its preparation method and application. The present application solves the problems of long curing time, insufficient environmental protection and insufficient insulation strength of the existing bird damage prevention coating through matrix modification, environmentally friendly bird repellent system and nano filler optimization, and realizes an innovative breakthrough in the technical route.

[0006] In order to achieve the above-mentioned purpose, one aspect of the present application provides an environmentally friendly low-viscosity insulating silicone rubber coating for bird damage prevention. The raw materials for preparing the environmentally friendly low-viscosity insulating silicone rubber coating for bird damage prevention contain methyl vinyl silicone rubber, nano alumina, modified fumed white carbon black, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer.

[0007] The methyl vinyl silicone rubber is used as the coating matrix; the nano alumina is used to improve the flowability and dispersibility of the coating; the modified fumed white carbon black is used to enhance the covering capacity and rheology of the coating; the bird repellent is used to prevent bird damage; the platinum catalyst is used to promote the curing of the active groups of the silicone rubber; the silane coupling agent is used to introduce active hydroxyl groups and improve the compatibility with fillers; the water is used as a solvent to promote dispersion; and the bio-based plasticizer is used to improve the physical properties of the coating. Preferably, the weight ratio of the methyl vinyl silicone rubber, nano alumina, modified fumed white carbon black, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer is 100:20-30:8-12:3-5:0.1-0.3:1-2:5-8:2-4.

[0008] If the amount of methyl vinyl silicone rubber is too small, the coating matrix will be insufficient, which cannot form a complete film structure, resulting in low coating strength, easy cracking, and significant reduction in insulation performance and adhesion. Other fillers (such as nano-aluminum oxide and modified fumed white carbon black) will lack sufficient matrix support and be unevenly dispersed, affecting overall performance. If the amount is too large, the viscosity of the coating will increase significantly, the flowability will deteriorate, uniform coating will be difficult during construction, and problems such as brush marks and accumulation may occur, leading to increased costs. Excessive methyl vinyl silicone rubber may also result in excessive coating flexibility, insufficient hardness, and poor wear resistance, affecting long-term use stability.

[0009] If the amount of nano-aluminum oxide is too small, the improvement effect on coating flowability and dispersibility will not be obvious, the filler will easily agglomerate, and problems such as precipitation and caking may occur during construction, affecting coating uniformity and leading to loose internal coating structure and reduced mechanical properties (such as tensile resistance and impact resistance). If the amount is too large, the nano-particles will be excessively filled, resulting in a significant increase in coating viscosity and deterioration of flowability, and even normal construction may not be possible. Excessive nano-aluminum oxide particles may also pierce the silicone rubber matrix structure, reducing the insulation and flexibility of the coating and increasing the risk of cracking.

[0010] If the amount of modified fumed white carbon black is too small, the coating rheology will be poor, and problems such as sagging, dripping, and uneven coverage may occur during coating, especially on complex surfaces (such as insulator concave-convex parts), making it difficult to form a complete coating. This will result in insufficient thixotropy of the coating, easy layering when standing, and poor surface flatness after construction. If the amount is too large, the coating will become paste-like (modified fumed white carbon black has strong thickening effect), losing flowability and making it impossible to spray or brush. This will increase the internal porosity of the coating and reduce its density, potentially damaging the bird repellent effect (such as uneven release of bird repellent) and insulation performance.

[0011] The bird repellent is the core component of bird repellent. If the amount is too small, the bird repellent effect will be weak, and birds will easily adapt to low-concentration agents, leading to ineffective bird repellent function and failing to achieve the intended protection purpose. If the amount is too large, the cost of the agent will increase significantly, and it may cause excessive stimulation to birds and even harm the ecological environment (such as exceeding the toxicity limit). Excessive bird repellent may also react with other components (such as methyl vinyl silicone rubber), damaging the coating structure and affecting insulation and weather resistance.

[0012] If the amount of platinum catalyst used in the present application is too small, the methyl vinyl silicone rubber curing reaction rate will be slow, and even complete curing cannot be achieved. The coating is in a viscoelastic state for a long time, is easy to stick to dust and sundries, and the mechanical properties (such as hardness and elasticity) do not meet the standards. Incomplete curing leads to poor aging resistance of the coating, which is easy to degrade in high temperature and humid environment. If the amount of platinum catalyst used is too large, the curing reaction will be too fast, the coating pot life (workable time) will be shortened, and the material may be wasted during construction. At the same time, excessive platinum catalyst may trigger side reactions, causing the coating to produce bubbles, discoloration or increased brittleness, affecting the appearance and performance.

[0013] Further, if the amount of silane coupling agent used is too small, the interfacial bonding force between the filler (such as nano-alumina oxide and modified fumed white carbon black) and the methyl vinyl silicone rubber matrix will be weak, and the coating will be prone to debonding and delamination, resulting in a decrease in the mechanical properties and insulation of the coating. The filler is easy to settle during storage of the coating, and the stability is poor. If the amount of silane coupling agent used is too large, free polar groups may be formed in the coating, increasing the moisture absorption of the coating, reducing the insulation resistance, and decreasing the electric breakdown resistance, resulting in increased cost and possibly affecting the curing reaction progress of the methyl vinyl silicone rubber.

[0014] If the amount of water used in the raw materials of the present application is too small, the coating will have high viscosity, the filler will not be fully dispersed, and the coating will have a grainy feel during construction, a rough surface, poor uniformity, and insufficient solvent may result in incomplete dissolution of components such as platinum catalyst, affecting the curing effect. If the amount of water used is too large, the solid content of the coating will be reduced, the coating thickness after film formation will be insufficient, the insulation performance and bird damage prevention function will be weakened, and too much water may leave pores in the coating during the evaporation process, reducing the density and prolonging the drying time, and reducing the construction efficiency.

[0015] If the amount of bio-based plasticizer used is too small, the coating will have insufficient flexibility and bending resistance, and will be prone to cracking under temperature changes or mechanical stress, especially in cold environments, and the physical properties (such as elongation and elastic recovery rate) will not meet the standards, affecting the long-term reliability. If the amount of bio-based plasticizer used is too large, the hardness and wear resistance of the coating will decrease significantly, and the coating will be easily pecked by birds or worn by external forces, shortening the service life, and excessive amounts may migrate to the surface of the coating, causing stickiness and dust absorption, and even affecting the release stability of the bird repellent.

[0016] In summary, the weight ratio of methyl vinyl silicone rubber, nano-alumina oxide, modified fumed white carbon black, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer in the present application is preferably controlled within the above range.

[0017] Further, in a specific embodiment, the weight ratio of methyl vinyl silicone rubber, nano-alumina oxide, modified fumed white carbon black, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer is 100:25:10:4:0.2:1.5:6:3.

[0018] In the preferred case of the present application, the particle size of the nano-alumina is 10-30 nm; controlling the particle size of the nano-alumina within a suitable range can improve the flowability and dispersibility In the present application, the bird repellent used is a natural plant bird repellent containing matrine extract, which is mainly used for making biological insecticides and has contact killing, stomach poisoning and antifeeding effects, and has significant control effect on various pests.

[0019] In the preferred case, the content of Pt element in the platinum catalyst is 450-550 ppm.

[0020] The silane coupling agent is selected from KH-570.

[0021] The second aspect of the present application provides a preparation method of the above-mentioned environment-friendly low-viscosity insulating silicone rubber coating for bird damage prevention, comprising the following steps: The methyl vinyl silicone rubber is premixed with the silane coupling agent to obtain a premix; The premix is mixed with nano-alumina and modified fumed white carbon black, followed by shearing and dispersing to obtain a slurry; The slurry is mixed with the bird repellent and water, and then ultrasonic treatment is performed to obtain a mixture; The mixture is mixed with the platinum catalyst and the bio-based plasticizer, and then vacuum degassing is performed to obtain the environment-friendly low-viscosity insulating silicone rubber coating for bird damage prevention.

[0022] The present application first premixes the methyl vinyl silicone rubber with the silane coupling agent by modifying the matrix, introduces active hydroxyl groups through the silane coupling agent to improve the compatibility with the filler; then performs filler dispersion, adds nano-alumina and modified fumed white carbon black, and uses shearing and dispersing to form a uniform slurry; then performs functionalization and compounding, adds natural plant bird repellent and deionized water, and realizes molecular-level mixing through ultrasonic treatment; finally adds the vulcanization system, sequentially adds the platinum catalyst and the bio-based plasticizer, and obtains the finished coating after vacuum degassing.

[0023] In the preferred case of the present application, the premixing conditions include a temperature of 50-70℃ and a time of 20-40 minutes; the premixing operation is to introduce active hydroxyl groups by means of the silane coupling agent to improve the compatibility with the filler, since the hydrolysis reaction and the hydroxylation process of the silane coupling agent require a suitable temperature, a temperature within 50-70℃ can both accelerate the hydrolysis of the silane coupling agent and promote the condensation reaction of the silane coupling agent with the hydroxyl groups on the surface of the filler (such as nano-alumina and modified fumed white carbon black) to form chemical bonds, thereby improving the compatibility, a temperature lower than 50℃ is too slow for the reaction rate, and a temperature higher than 70℃ may cause excessive hydrolysis and decomposition of the silane coupling agent, affecting the subsequent curing reaction; at the same time, 20-40 minutes can ensure sufficient reaction and avoid energy waste and oxidation risk of the materials (such as the possibility of oxidation of the bio-based plasticizer when it is in contact with air for a long time at high temperature).

[0024] Further, in the present application, the shearing dispersion conditions include a rotation speed of 2000-3000 rpm and a time of 1-2 hours; a rotation speed of 2000-3000 rpm can generate sufficient shear force to effectively break the agglomerates of the filler and make the filler uniformly dispersed in the methyl vinyl silicone rubber matrix in the form of nano-sized particles, a too low rotation speed is insufficient for the shear force, and a too high rotation speed may cause overheating or structural damage of the materials, and a shearing dispersion time of 1-2 hours can ensure sufficient dispersion and avoid oxidation of the materials (such as moisture absorption of the methyl vinyl silicone rubber when it is in contact with air for a long time) or degradation of the additives caused by long-time shearing.

[0025] Preferably, the ultrasonic mixing in the present application can achieve molecular-level mixing, which helps to mix the materials more fully and uniformly, wherein the ultrasonic conditions include a frequency of 40-60 kHz and a time of 30-50 minutes; 40-60 kHz belongs to the high-frequency ultrasonic range, which is suitable for breaking the soft agglomerates of nano-sized fillers (such as nano-alumina and modified fumed white carbon black), while avoiding material impact damage caused by large air bubbles due to low-frequency ultrasonic. Within 30-50 minutes of ultrasonic, the temperature rise (usually ≤5℃) caused by ultrasonic cavitation is basically stable, and if the ultrasonic time is too long, the accumulated cavitation heat may cause volatilization loss of the bird repellent.

[0026] In the present application, the vacuum degassing conditions include a vacuum degree of ≤0.1 MPa (a vacuum degree that is insufficient will cause residual air bubbles, affecting the insulation and bird prevention functions; a vacuum degree that is too high will cause volatilization of the additives and degradation of the matrix), and a time of 20-40 minutes.

[0027] The third aspect of the present application provides an application of the environmentally friendly low-viscosity insulating silicone rubber coating for bird prevention in power transmission and distribution lines.

[0028] The environmentally friendly low-viscosity insulating silicone rubber coating for bird prevention prepared by the above preparation method has the following advantages compared with the prior art: 1. Low viscosity base design, through branched modification of vinyl silicone rubber molecular chain and synergistic effect of bio-based plasticizer, spraying or dipping. Low viscosity characteristics are suitable for spraying of complex structure, strong penetration, single coating thickness can reach 0.5mm, which is beneficial to practical application and construction.

[0029] 2. The coating can be quickly cured. Platinum catalyst system directly reacts with active groups of silicone rubber. Curing time is ≤20 minutes at 80℃, and curing time is ≤1.5 hours at room temperature. Two-stage vulcanization is not required.

[0030] 3. High efficiency protection. Three-dimensional insulating network is formed by nano-alumina and modified fumed white carbon black. Breakdown strength is ≥25kV / mm (GB / T 1408.1-2016). In combination with the bird repellent odor avoidance mechanism, the risk of bird damage is reduced.

[0031] 4. Green and environmentally friendly. Water is used as a solvent, and natural plant bird repellent is used to replace chemical bird repellent. VOC content is <30g / L (GB30981-2020). There is no benzene solvent, and the bio-based plasticizer can be naturally degraded, which meets the EU RoHS and REACH standards.

[0032] 5. Long-acting and durable. The coating is resistant to ultraviolet aging for >6000 hours (ISO 4892-2), and the service life is ≥20 years, thereby reducing maintenance costs. DETAILED DESCRIPTION

[0033] The specific embodiments of the present application will be described in detail below in conjunction with the examples. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0034] The endpoints of the ranges and any values disclosed herein are not limited to the precise values stated. The ranges or values should be construed to include values approximately around the ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0035] The present application will be described in detail below through examples. The experimental methods in the following examples are conventional methods in the art, unless otherwise specified.

[0036] The modified fumed white carbon black used in the following examples was purchased from Shandong Aochuang Chemical Co., Ltd., the bird repellent was purchased from Rayno (Beijing) Biotechnology Co., Ltd., the platinum catalyst was purchased from Araldin Chemical Reagent, the silane coupling agent was purchased from Jiangxi Chen Guang New Material Co., Ltd., and the bio-based plasticizer was purchased from Shandong Jiqing Chemical Co., Ltd.

[0037] Example 1 (1) methyl vinyl silicone rubber and silane coupling agent (KH-570) were premixed at 60℃ for 30 minutes to obtain a premix; (2) nano-alumina (particle size 20nm) and modified fumed white carbon black were added to the premix obtained in step (1), followed by shearing and dispersing for 1.5 hours at 2500 rpm using a high-speed shearing machine to form a uniform slurry; (3) the slurry obtained in step (2) was mixed with a natural plant bird repellent containing sophoridine extract and deionized water, and then ultrasonic treatment was performed at 50 kHz for 40 minutes to achieve molecular-level mixing, thereby obtaining a mixture; (4) the mixture obtained in step (3) was mixed with a platinum catalyst having a Pt element content of 500 ppm and a bio-based plasticizer, and then vacuum degassing was performed under the following conditions: vacuum degree 0.08 MPa, time 30 minutes, thereby obtaining an environmentally friendly low-viscosity insulating silicone rubber coating A1 for bird damage prevention; The weight ratio of methyl vinyl silicone rubber, nano-alumina, modified fumed white carbon black, natural plant bird repellent, platinum catalyst, silane coupling agent, deionized water and bio-based plasticizer is 100:25:10:4:0.2:1.5:6:3.

[0038] Example 2 The method of Example 1 was followed, except that the weight ratio of methyl vinyl silicone rubber, nano-alumina, modified fumed white carbon black, natural plant bird repellent, platinum catalyst, silane coupling agent, deionized water and bio-based plasticizer was 100:20:8:3:0.1:1:5:2, thereby obtaining an environmentally friendly low-viscosity insulating silicone rubber coating A2 for bird damage prevention.

[0039] Example 3 The method of Example 1 was followed, except that the weight ratio of methyl vinyl silicone rubber, nano-alumina, modified fumed white carbon black, natural plant bird repellent, platinum catalyst, silane coupling agent, deionized water and bio-based plasticizer was 100:30:12:5:0.3:2:8:4, thereby obtaining an environmentally friendly low-viscosity insulating silicone rubber coating A3 for bird damage prevention.

[0040] Example 4 (1) methyl vinyl silicone rubber and silane coupling agent (KH-570) were premixed at 50℃ for 20 minutes to obtain a premix; (2) nano-alumina (particle size 20nm) and modified fumed white carbon black were added to the premix obtained in step (1), followed by shearing and dispersing for 1 hour at 2000 rpm using a high-speed shearing machine to form a uniform slurry; (3) Adding the natural plant bird repellent containing the extract of matrine and deionized water into the slurry obtained in step (2) to mix, and then treating by ultrasonic wave, ultrasonic treatment is performed at 40 kHz for 30 minutes to realize molecular level mixing, to obtain a mixture; (4) Adding the platinum catalyst with Pt element content of 450 ppm and the bio-based plasticizer into the mixture obtained in step (3) to mix, and then performing vacuum degassing, the vacuum degassing conditions include: vacuum degree of 0.08 MPa, time of 30 minutes, to obtain the environment-friendly low-viscosity insulating silicone rubber coating A4 for bird damage prevention; The weight ratio of the methyl vinyl silicone rubber, the nano alumina, the modified fumed white carbon black, the natural plant bird repellent, the platinum catalyst, the silane coupling agent, the deionized water and the bio-based plasticizer is 100:25:10:4:0.2:1.5:6:3.

[0041] Example 5 (1) Pre-mixing the methyl vinyl silicone rubber and the silane coupling agent (KH-570) at 60°C for 20 minutes to obtain a pre-mixture; (2) Adding the nano alumina (particle size of 20 nm) and the modified fumed white carbon black into the pre-mixture obtained in step (1) to mix, and then shearing and dispersing by using a high-speed shearing machine at 2000 rpm for 2 hours to form a uniform slurry; (3) Adding the natural plant bird repellent containing the extract of matrine and deionized water into the slurry obtained in step (2) to mix, and then treating by ultrasonic wave, ultrasonic treatment is performed at 45 kHz for 45 minutes to realize molecular level mixing, to obtain a mixture; (4) Adding the platinum catalyst with Pt element content of 500 ppm and the bio-based plasticizer into the mixture obtained in step (3) to mix, and then performing vacuum degassing, the vacuum degassing conditions include: vacuum degree of 0.08 MPa, time of 20 minutes, to obtain the environment-friendly low-viscosity insulating silicone rubber coating A5 for bird damage prevention; The weight ratio of the methyl vinyl silicone rubber, the nano alumina, the modified fumed white carbon black, the natural plant bird repellent, the platinum catalyst, the silane coupling agent, the deionized water and the bio-based plasticizer is 100:25:10:4:0.2:1.5:6:3.

[0042] Example 6 (1) Pre-mixing the methyl vinyl silicone rubber and the silane coupling agent (KH-570) at 70°C for 40 minutes to obtain a pre-mixture; (2) Adding the nano alumina (particle size of 20 nm) and the modified fumed white carbon black into the pre-mixture obtained in step (1) to mix, and then shearing and dispersing by using a high-speed shearing machine at 3000 rpm for 2 hours to form a uniform slurry; (3) Adding the natural plant bird repellent containing the extract of matrine and deionized water into the slurry obtained in step (2) and mixing, and then treating by ultrasonic wave for 50 minutes at 60 kHz to realize molecular level mixing, to obtain a mixture; (4) Adding the platinum catalyst with a Pt element content of 550 ppm and the bio-based plasticizer into the mixture obtained in step (3) and mixing, and then vacuum degassing, the conditions of vacuum degassing including: vacuum degree of 0.08 MPa, time of 30 minutes, to obtain the environment-friendly low-viscosity insulating silicone rubber coating A6 for bird damage prevention; The weight ratio of the methyl vinyl silicone rubber, the nano-aluminum oxide, the modified fumed white carbon black, the natural plant bird repellent, the platinum catalyst, the silane coupling agent, the deionized water and the bio-based plasticizer is 100:25:10:4:0.2:1.5:6:3.

[0043] Test Example 1 A1, A2, A3, A4, A5 and A6 were respectively coated on the surface of a power transmission cross arm, and cured at 80℃ for 18 minutes or at room temperature (25℃) for 1.5 h to obtain coatings, respectively, and the properties of the coatings were tested, respectively. (1) Breakdown strength of the coating Test method: Referring to GB / T 1408.1-2016 Insulating materials – Determination of the electrical strength – Part 1: Test at power frequency.

[0044] The breakdown strength of the coating of Example 1-6 was 26.8 kV / mm, 25.1 kV / mm, 27.5 kV / mm, 25.8 kV / mm, 27.0 kV / mm, 26.5 kV / mm, respectively.

[0045] (2) Surface dry time (25℃) Test method: Referring to ASTM D5895 Standard Test Method for Evaluating Drying or Curing in the Film Formation Process of Organic Coatings Using a Mechanical Recorder.

[0046] The surface dry time (25℃) of Example 1-6 was 35 minutes, 33 minutes, 37 minutes, 34 minutes, 38 minutes, 36 minutes, respectively.

[0047] (3) VOC emission Test method: Referring to GB 30981-2020 Limitation of hazardous substances in industrial protective coatings.

[0048] The VOC emission of Example 1-6 was 28 g / L, 27 g / L, 29 g / L, 28 g / L, 27 g / L, 29 g / L, respectively.

[0049] (4) Salt spray resistance (1000 h) Test method: Refer to ISO 9227 Corrosion tests in artificial atmospheres - Salt spray tests.

[0050] The salt spray resistance (1000h) test results of Examples 1-6 were all free of rust and peeling.

[0051] (5) Bird repellency effectiveness (in the field) Bird repellency effectiveness is reflected by the bird damage accident rate before and after the application of the coating.

[0052] The bird damage accident rates of Examples 1-6 were reduced by 92%, 85%, 86%, 87%, 85%, and 88%, respectively.

[0053] (6) Coating resistance to ultraviolet aging Test method: Refer to ISO 4892-2 Plastics - Laboratory light source exposure methods.

[0054] The ultraviolet aging resistance of Examples 1-6 was all >6000 hours.

[0055] (7) Volume resistivity Test method: Refer to DL / T 627-2018 Insulating Substances - Room Temperature Vulcanizing Silicone Rubber Anti-Fouling Flashover Coating.

[0056] Test conditions: t d = 25.0℃ P = 101.8kPa RH = 55% Sample size: Ф100 Before testing, clean the sample and place it in a dry box at 25℃ for 24h.

[0057] The volume resistivity of Examples 1-6 is shown in Table 1.

[0058] Table 1 (8) Dielectric strength Test method: Refer to DL / T 627-2018 Insulating Substances - Room Temperature Vulcanizing Silicone Rubber Anti-Fouling Flashover Coating.

[0059] Test conditions: t d = 25.0℃ P = 101.3kPa RH = 54% Sample size: Ф100 During testing, immerse the sample in clean transformer oil and test the breakdown voltage of the sample using the voltage boosting method.

[0060] The dielectric strength of Examples 1-6 is shown in Table 2.

[0061] Table 2 A1, A2, A3, A4, A5 and A6 were subjected to tracking and erosion resistance test, test method: refer to DL / T 627-2018 Anti-fouling Flashover Coating for Insulators with Normal Temperature Cured Silicone Rubber.

[0062] Test conditions: t d =25.0℃ P=101. 8kPa RH=54% The paint was poured into a clean and dry mold, and after 10 days of curing, test samples of the required size were prepared for tracking and erosion resistance test.

[0063] The tracking and erosion resistance of examples 1-6 are shown in table 3.

[0064] Table 3 The above results show that the bird-deterrent environmentally friendly low-viscosity insulating silicone rubber coating of the present application all have good insulation performance and bird-deterrent effect; with the increase of the addition amount of nano alumina and modified fumed white carbon black, the insulation strength (coating breakdown strength) of the coating increases; the increase of the amount of natural plant bird repellent will lead to the increase of VOC emission of the coating, but the more the amount of natural plant bird repellent, the better the bird-deterrent effectiveness in the field. According to the above test results, the comprehensive performance of the formulation of example 1 is better.

[0065] It should be understood that parts not elaborated in the specification are all prior art.

[0066] The preferred embodiments of the present application are described in detail above, but the present application is not limited thereto. Within the technical concept of the present application, various simple modifications can be made to the technical solutions of the present application, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be considered as disclosed by the present application and fall within the protection scope of the present application.

Claims

1. An environmentally friendly low-viscosity insulating silicone rubber coating for bird protection, characterized in that: The raw materials for preparing the environmentally friendly low-viscosity insulating silicone rubber coating for preventing bird damage contain methyl vinyl silicone rubber, nano-alumina, modified fumed silica, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer.

2. The environmentally friendly low-viscosity insulating silicone rubber coating for bird damage prevention according to claim 1, characterized in that: The weight ratio of the methyl vinyl silicone rubber, nano-aluminum oxide, modified fumed silica, bird repellent, platinum catalyst, silane coupling agent, water and bio-based plasticizer is 100:20-30:8-12:3-5:0.1-0.3:1-2:5-8:2-4.

3. The environmentally friendly low-viscosity insulating silicone rubber coating for bird damage prevention according to claim 1, characterized in that: The particle size of the nano-alumina is 10-30 nm; The bird repellent contains matrine extract; The content of Pt element in the platinum catalyst is 450-550 ppm.

4. The environmentally friendly low-viscosity insulating silicone rubber coating for preventing bird damage according to claim 1 or 3, characterized in that: The silane coupling agent is selected from KH-570.

5. The method for preparing the environmentally friendly low-viscosity insulating silicone rubber coating for preventing bird damage according to any one of claims 1 to 4, characterized in that: The following steps are involved: premixing methyl vinyl silicone rubber and a silane coupling agent to obtain a premix; The premix is ​​mixed with nano-alumina and modified fumed silica, and then sheared and dispersed to obtain a slurry; mixing the slurry with a bird repellent and water, and then performing sonication to obtain a mixture; The mixture is mixed with a platinum catalyst and a bio-based plasticizer and then subjected to vacuum degassing to obtain an environmentally friendly low-viscosity insulating silicone rubber coating for preventing bird damage.

6. The preparation method according to claim 5, characterized in that The premixing conditions include: a temperature of 50-70° C. and a time of 20-40 minutes.

7. The preparation method according to claim 5, characterized in that The shear dispersion conditions include: a rotation speed of 2000-3000 rpm and a time of 1-2 hours.

8. The preparation method according to claim 5, characterized in that The ultrasonic conditions include: a frequency of 40-60 kHz and a time of 30-50 minutes.

9. The preparation method according to claim 5, characterized in that The conditions for the vacuum degassing include: vacuum degree ≤ 0.1 MPa, and time of 20-40 minutes.

10. Use of the environmentally friendly low-viscosity insulating silicone rubber coating for preventing bird damage according to any one of claims 1 to 4 in power transmission and distribution lines.

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