Preparation of Anti Mold Cleaning Agent and its Effect on the Performance of Insulation Materials

A mold resistant cleaning agent with long-term cleaning function was prepared using hydroxyl silicone oil, mold inhibitors, and some additives as the main raw materials. The results show that the anti mold cleaning agent prepared by adding different proportions of anti mold agents not only ensures the cleaning and anti mold effects on the insulation material, but also has no significant impact on its mechanical properties, electrical properties, and surface hydrophobicity. Moreover, when the content of the anti mold cleaning agent is 2% to 3%, its comprehensive mechanical and electrical properties can maintain a good level. Through infrared analysis, it can be seen that during the mixing process of cleaning agent and anti mold agent, due to the consumption of some double bonds, the internal molecular structure of the cleaning agent has been changed, which not only has good cleaning effect but also excellent anti mold effect. When the amount of anti mold agent is 2%, the anti mold level of the insulation material is the best, reaching level 0, and the hydrophobicity can also reach HC1 after cleaning.


Introduction
With the development of the power industry, the demand for insulation materials is increasing day by day.However, with the increasingly deteriorating environment, external insulation equipment in power systems is increasingly prone to pollution flashover accidents, which will seriously affect the safe operation of the power grid.Especially in some harsh environments, the surface of power equipment can be corroded by mold, leading to mold growth or moss growth on the surface, endangering its insulation performance and reducing the power conversion rate [1][2][3].As the erosion time prolongs, it may even damage the power equipment itself.The usual solution to the occurrence of pollution flashover accidents is to spray traditional anti pollution flashover coatings.However, due to the shorter lifespan of anti fouling flashover coatings compared to power equipment, and the long-term operation of anti fouling flashover coatings, they also face practical problems such as severe fouling, decreased hydrophobicity, and susceptibility to mold [4].
Due to the influence of climate and other environmental factors, in areas with frequent rainfall, fog, and humid air, plants such as moss and algae thrive heavily on external insulation equipment [5].Especially in rainy, foggy, and humid weather, mold, moss, etc. attached to the insulation surface of electrical equipment will form a conductive film on the surface of the power equipment, greatly reducing the insulation level of the insulation material.It is easy to cause the occurrence of pollution flashover, which can lead to tripping.The voltage level and transmission capacity of ultra-high voltage transmission lines are high, and once a tripping accident occurs, it will cause large-scale power outages and even cause power system oscillations, affecting the normal electricity consumption of the people [6].Therefore, in order to ensure the safe and stable operation of power equipment and prevent the adhesion of microorganisms such as mold and moss from causing pollution flashover on the surface of insulation materials, it is urgent to study an effective, convenient, and easy to use measure to improve hydrophobicity, prevent fouling, mold, and moss to solve various problems faced by power equipment due to humidity [7][8][9][10][11][12].
This article aims to study an excellent anti mold cleaning agent applied to the surface of insulation materials, which can prevent flashover of insulators caused by the adhesion and metabolism of microorganisms such as mold and moss.At present, there are few finished products of anti mold cleaning agents applied to insulators, and the anti mold effect is not very prominent.When the hydrophobicity of the surface of silicone rubber decreases, its anti mold effect naturally disappears.The main component of the anti mold cleaning agent used in this article is organic silicon, which effectively maintains the hydrophobicity of the insulator surface while extending its anti mold effect.This article mainly utilizes the migration and substitution reactions of double bonds, by adding different amounts of anti mold agents to the cleaning agent to undergo chemical reactions, to prepare a cleaning agent that not only has cleaning effects, but also has antibacterial and anti mold effects on insulation materials, solving the thorny problem of easily adhering dirt and producing mold on the surface of insulation materials.

Sample Preparation
Weigh hydroxy silicone oil and RJ-1419 according to the ratio, mix them at a high speed at a stirring rate of 800~1000r/min, adjust the stirring rate after 20~30min, add KH550, KH560 and mildew inhibitor at a low stirring rate, increase the stirring rate to 1200~1500r/min, and mix for 20~30min.Prepare an anti mold cleaning agent after standing for 4-6 hours.Finally, wipe the silicone rubber insulation material with anti mold cleaning agent, air dry, and wait for testing.

Performance Testing
The main performance indicators can be tested according to the following standards: DL/T 627-2018 "Room temperature cured silicone rubber anti pollution flashover coating for insulators" for hydrophobicity testing; GB/T 1741-2020 "Determination of Mold Resistance of Paint Films" for testing mold resistance; GB/T 528-2009 "Determination of tensile stress-strain properties of vulcanized or thermoplastic rubber" for testing tensile strength and elongation at break; GB/T 529-2008 "Determination of Tear Strength of Vulcanized or Thermoplastic Rubber (Trouser shaped, Square shaped, and Crescent shaped Specimens)" for testing tear strength.

The Effect of Anti Mold Cleaning Agents on the Mechanical Properties of Insulation Materials
This study mainly investigates the effect of the amount of mold inhibitor on the mechanical properties of insulation materials, including the hardness, tensile strength, elongation at break, and tear strength of the insulation materials.Table 1 shows the changes in the impact of mold inhibitors on the mechanical properties of insulation materials, while figure 1 shows the changes in the impact of mold inhibitors on the mechanical properties of insulation materials.From table 1 and figure 1, it can be seen that the addition of mold inhibitors did not cause significant changes in the mechanical properties of the insulation material, and it was able to maintain a relatively good level of mechanical properties of the insulation material.As the content of the mold inhibitor increases, the tensile strength first increases and then decreases.When the content of the mold inhibitor is 2%, the tensile strength value is the highest, at 2.45MPa.Other mechanical properties have similar trends of change, and when the content of mold inhibitor is 2%, its hardness value is 46.2, elongation at break is 75%, and tear strength is 6.5 KN/m.
In summary, when the amount of mold inhibitor added is 2%, the mechanical properties of the insulation material are the best, and the addition of mold inhibitor does not harm the mechanical properties of the insulation material.

The Effect of Anti Mold Cleaning Agents on the Electrical Properties of Insulation Materials
This study mainly investigates the effect of the amount of mold inhibitor on the electrical properties of insulation materials.Table 2 shows the changes in the impact of mold inhibitors on the electrical properties of insulation materials, while figure 2 shows the changes in the impact of mold inhibitors on the electrical properties of insulation materials.From table 2 and figure 2, it can be seen that after the addition of mold inhibitors, the electrical properties of the insulation material have undergone significant changes, with a certain degree of improvement, and the electrical properties of the insulation material can be maintained at a good level.As the content of the mold inhibitor increases, the breakdown strength shows a trend of first increasing and then decreasing.When the content of the mold inhibitor is 3%, the breakdown strength value is the highest, at 22.52 KV/mm.

The Effect of Anti Mold Cleaning Agents on the Hydrophobicity of Insulation Materials After Surface Treatment
This study mainly investigates the effects of different cleaning methods and the amount of anti mold cleaning agents on the surface hydrophobicity of insulation materials.Table 3 shows the changes in the influence of anti mold cleaning agents on the hydrophobicity of insulation materials.From table 3, it can be seen that the surface of the uncleaned insulation material has poor hydrophobicity, with a hydrophobicity level of HC4.After water cleaning, its hydrophobicity is still not ideal, with a hydrophobicity level of HC3.After using cleaning agents to clean the surface of insulation materials, their hydrophobicity has significantly improved, with the hydrophobicity level raised from HC4 to HC1.Moreover, adding anti mold agents did not have a significant impact on its hydrophobicity, but rather maintained its good hydrophobicity level.

Analysis of Infrared Characteristic Peaks of Anti Mold Cleaning Agents
This study conducted infrared analysis on cleaning agents, anti mold agents, and anti mold cleaning agents, respectively.The results of the characteristic groups and peak areas of each component are shown in table 4. The wave number of 1505-1407cm -1 is mainly the deformation vibration and stretching vibration of -CH3, while the wave number of 758-650cm -1 is mainly the deformation vibration and stretching vibration of C-H and -CH2-.The peak area of 758-650cm -1 in the mold inhibitor is negative.However, when it is added to the cleaning agent, it is found that its peak area is positive and lower than the corresponding peak area of the cleaning agent.During the mixing process of cleaning agent and anti mold agent, some double bonds were consumed and converted into -CH2-, causing -CH2-to undergo deformation and vibration.Analyze the peak area corresponding to the wave number of 1505-1407cm -1 for the anti mold cleaning agent, and its value is in the middle of the cleaning agent and anti mold agent, indicating that -CH3 has undergone stretching vibration.In summary, during the mixing process of cleaning agent and anti mold agent, chemical changes occurred, consuming some double bonds, resulting in a change in the molecular structure of the cleaning agent.

The Effect of Anti Mold Cleaning Agents on the Anti Mold Performance of Insulation Materials
Table 5 shows the impact level results of mold inhibitors on the mold resistance of insulation materials.
There are 8 types of fungi in this experiment, including Aspergillus niger, Aspergillus terrestris, and Paecilomyces vannamei; The preparation and cultivation of bacterial strains takes 28 days; The test duration is 28 days, and the test temperature should be maintained between 28 ℃ and 30 ℃.The temperature change should not exceed 1 ℃/h; The relative humidity inside the test chamber is always greater than 90%.From table 5, it can be seen that when anti mold agents are not added, the anti mold effect of the insulation material is extremely poor, and its surface is prone to mold growth.After adding anti mold agents, the anti mold performance of insulation materials is significantly improved.And when the amount of anti mold agent is 2%, the anti mold level of the insulation material reaches level 0, which is the optimal level; When the amount of anti mold agent is 1%, 3%, and 4%, the anti mold level of the insulation material is level 1, and the anti mold effect is poor.Therefore, the optimal dosage of this mold inhibitor is 2%.Table 6 shows the levels of mold growth and their annotations.

Conclusion
(1) The study of anti mold cleaning agents prepared by adding different proportions of anti mold agents found that they had no significant effect on the mechanical properties, electrical properties, and surface hydrophobicity of insulation materials.Moreover, when the content of anti mold agents was 2% to 3%, they had a promoting effect on the comprehensive performance of insulation materials.
(2) Through infrared analysis, some double bonds were consumed during the mixing process of cleaning agents and mold inhibitors, which were converted into -CH2-, causing -CH2-to undergo deformation and vibration.The molecular structure of the cleaning agent has been changed, which can effectively promote its cleaning effect on insulation materials.
(3) In addition, through infrared spectroscopy analysis, it is known that during the mixing process of cleaning agent and antifungal agent, a large amount of double bonds, namely olefin small molecules, are consumed, resulting in a significant reduction in spatial hindrance in the internal molecular structure of the antifungal cleaning agent, a decrease in electron cloud density, and an increase in degrees of freedom, thereby maintaining its mechanical and electrical properties in a relatively stable state and not easily damaged.
(4) This anti mold cleaning agent not only has good cleaning effect, but also has good anti mold effect.When the content of mold inhibitor is 2%, the best mold proof level of insulation material is level 0. At this point, the hydrophobicity can also reach HC1.
(5) This anti mold cleaning agent can not only be applied in the field of cleaning the external surface of insulation equipment, but also provide a theoretical basis for research on improving the surface hydrophobicity of insulation materials and extending their service life.

Figure 1 .
Figure 1.Changes in the influence of mold inhibitors on the mechanical properties of insulation materials.

Figure 2 .
Figure 2. Changes in the influence of mold inhibitors on the electrical properties of insulation materials.

Table 1 .
Effect of anti mold cleaning agent on the mechanical properties of silicone rubber.

Table 2 .
Effect of antimold cleaning agent on the electrical properties of insulation materials.

Table 3 .
Changes in the influence of anti mold cleaning agents on the hydrophobicity of insulation materials.

Table 4 .
Characteristic group peak area of anti mold cleaning agent.

Table 5 .
Effect of antimold agents on the antimold performance of insulation materials.

Table 6 .
Grade of mold growth and notes.