Method for repairing damage defect of anti-atomic oxygen siloxane coating

Abstract

The invention relates to a method for repairing damage defects of an anti-atomic oxygen siloxane coating, and belongs to the technical field of anti-atomic oxygen protection. The problems of rapid repair of damage defects such as macroscopic cracks and local falling generated in the service process of folding, unfolding, vibration and collision of an existing siloxane coating are solved by adopting a spraying and brushing method. The repairing material is prepared from dimethyl siloxane, perhydropolysilazane and inorganic filler nano silicon oxide and nano aluminum oxide. The thickness, the uniformity and the density of the repairing material and the binding force of the repairing material and the base material are accurately controlled by finely regulating and controlling repairing process parameters in combination with spraying and brushing technologies. Through vacuum drying and ultraviolet light cross-linking curing of the repairing coating at the same time, the repairing of damage defects is realized.

Description

Technical Field

[0001] The invention relates to a method for repairing damage defects of an antiprotoxin siloxane coating, belonging to the technical field of antiprotoxin protection. Background Art

[0002] A large amount of organic polymer materials are used on the surface of low-orbit satellites. However, there is a large amount of atomic oxygen in the low-Earth orbit environment. The impact of atomic oxygen and its strong oxidizing effect will cause changes in the chemical composition and quality loss of organic polymers, resulting in a decrease in their mechanical, electrical, optical and other properties. At present, in order to improve the anti-proton oxygen performance of large-area organic polymer film materials, the use of plasma-enhanced chemical vapor deposition technology to deposit siloxane protective film coatings is one of the most effective protective methods. However, during the preparation, transportation, launch and application of siloxane protective coatings, more or less defects, cracks, and shedding will occur in the coatings, resulting in damage defects in the coatings. These damage defects provide a channel for atomic oxygen to enter the base material, causing atomic oxygen to "penetrate" and hollow out under the protective layer, causing the protective coating to tear and fall off, and then leading to the failure of protective measures, resulting in greater harm. Re-preparing the coating and replacing new parts is difficult, time-consuming and costly. If the damaged parts of the coating are repaired, the coating damage problem can be solved quickly and efficiently. Therefore, it is of great significance to develop repair technology for anti-proton oxygen coating materials. Summary of the invention

[0003] In view of this, the purpose of the present invention is to propose a method for repairing damage defects of antigenic oxygen siloxane coatings, which adopts spraying and brushing methods to solve the problem of rapid repair of damage defects such as macro cracks and local detachment generated in the service process of folding, unfolding, vibration and collision of existing siloxane coatings, and enhance the bonding strength and density between the repair area and the substrate and the original coating.

[0004] To achieve the above object, the present invention provides a method for repairing damage defects of an antigenic siloxane coating, the method comprising the following steps:

[0005] (1) Use a high-pressure blower to purge the damaged area of ​​the coating to clean up the floating dust and impurities in the area to be repaired. The wind speed is 5-15m / s, the purge angle is 30°-45°, the purge distance is 100mm-300mm, and the purge time is 5s-10s;

[0006] (2) spraying the repair material onto the coating damage defect area;

[0007] (3) Then, the uniformity, bonding strength and thickness of the repair material after spraying are regulated by brushing / scraping, so as to achieve the effect of defect filling and tight bonding. The brushing method is cross brushing, and the coating thickness is controlled to be 0.5-10 microns;

[0008] (4) Using vacuum drying and UV light cross-linking to cure the repair coating to achieve the repair of coating damage. The curing method is first vacuum drying for 10-100 minutes to volatilize the solvent in the repair material. The UV spectrum range is 200-400nm, and the irradiation time is 1-72h, so that the coating can achieve the effect of light curing and cross-linking film formation;

[0009] In the step (2), the repair material is composed of dimethylsiloxane (50-60wt%), perhydropolysilazane (20-30wt%), nano silicon oxide (5-15wt%) and nano aluminum oxide (5-15wt%) powders diluted into a viscous solution, and the diluent is a solvent such as cyclohexane, toluene, and n-butyl ether;

[0010] The siloxane coating to be repaired is a siloxane coating deposited by plasma enhanced chemical vapor deposition.

[0011] Beneficial Effects

[0012] The present invention provides a method for repairing damage defects of antigenic oxygen siloxane coatings, which adopts spraying and brushing methods to solve the problem of rapid repair of damage defects such as macro cracks and local shedding generated in the existing siloxane coating during the service process of folding, unfolding, vibration, and collision. The repair material is composed of dimethylsiloxane, perhydropolysilicon nitrogen, and inorganic fillers nano silicon oxide and nano aluminum oxide. Combining spraying and brushing technology, the thickness, uniformity, density of the repair material, and the bonding force between the repair material and the substrate are precisely controlled by finely regulating the repair process parameters. The repair coating is cured by ultraviolet cross-linking by vacuum drying to achieve the repair of damage defects. This repair method has the advantages of accurate positioning of the damaged area, simple, fast and convenient repair process, and low cost. It can quickly solve the problem of coating defect damage in the satellite protection part when it is waiting to be launched and in orbit.

[0013] The present invention discloses a design method for a high-density composite atomic oxygen protective film. Spraying and brushing methods are used to solve the problem of rapid repair of damage defects such as macro cracks and local shedding generated in the existing siloxane coating during the service process of folding, unfolding, vibration, and collision. The repair material is composed of dimethylsiloxane, perhydropolysilicon nitrogen, and inorganic fillers nano silicon oxide and nano aluminum oxide. Combining spraying and brushing technology, the repair process parameters are finely regulated to accurately control the thickness, uniformity, density of the repair material, and the bonding force between the repair material and the substrate. The repair coating is cured by ultraviolet cross-linking by vacuum drying to achieve the repair of damage defects. This repair method has the advantages of accurate positioning of the damaged area, simple, fast and convenient repair process, and low cost. It can quickly solve the problem of coating defect damage in the satellite protection part when it is waiting to be launched and in orbit. DETAILED DESCRIPTION

[0014] The present invention will be further described below in conjunction with the embodiments.

[0015] Example

[0016] A method for repairing damage defects of an antigen-resistant siloxane coating, the method comprising the following steps:

[0017] (1) Use a high-pressure blower to purge the damaged area of ​​the coating to clean up the floating dust and impurities in the area to be repaired. The wind speed is 10m / s, the purge angle is 45°, the purge distance is 200mm, and the purge time is 10s;

[0018] (2) The repair material is composed of dimethylsiloxane (60 wt%), perhydropolysilazane (30 wt%), nano-silicon oxide (5 wt%) and nano-aluminum oxide (5 wt%) powders diluted into a viscous solution, and the diluent is cyclohexane;

[0019] The repair material is sprayed onto the coating damage defect area by spraying;

[0020] (3) Then, the uniformity, bonding strength and thickness of the repair material after spraying are regulated by brushing / scraping so as to achieve the effect of defect filling and tight bonding. The brushing method is cross brushing, and the coating thickness is controlled to be 30 μm.

[0021] (4) Adopting vacuum drying and UV light cross-linking and curing to repair the coating to achieve the repair of coating damage. The curing method is first vacuum drying for 60 minutes to volatilize the solvent in the repair material. The UV spectrum range is 200-400nm, and the irradiation time is 48 hours, so that the coating can achieve the effect of light curing and cross-linking film formation;

[0022] The siloxane coating to be repaired is a siloxane coating deposited by plasma enhanced chemical vapor deposition.

[0023] After the repair, the electron scanning electron microscope and atomic oxygen irradiation experimental tests were carried out. The test results showed that the coating defect area was filled and repaired by the repair material. After the atomic oxygen irradiation test, the atomic oxygen was prevented from corroding the base material, and the coating defect repair function was achieved.

[0024] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for repairing damage defects of an antigen-resistant siloxane coating, characterized in that The method comprises the following steps: (1) Use a high-pressure blower to purge the damaged area of ​​the coating to clean up the floating dust and impurities in the area to be repaired. The wind speed is 5-15m / s, the purge angle is 30°-45°, the purge distance is 100mm-300mm, and the purge time is 5s-10s; (2) spraying the repair material onto the coating damage defect area; (3) Then, the uniformity, bonding strength and thickness of the sprayed repair material are regulated by brushing / scraping to achieve the effect of defect filling and tight bonding. The brushing method is cross-shaped brushing, and the coating thickness is controlled to be 0.5-50 μm; (4) The coating is repaired by vacuum drying and UV cross-linking to achieve the repair of coating damage.

2. A method for repairing damage defects of an antigenic oxygen-resistant siloxane coating according to claim 1, characterized in that: In the step (4), the curing method is first vacuum drying for 10-100 minutes to volatilize the solvent in the repair material.

3. A method for repairing damage defects of an antigenic siloxane coating according to claim 1, characterized in that: In the step (4), the ultraviolet spectrum range is 200-400nm, and the irradiation time is 1-72h, so that the coating can achieve the effect of photocuring and cross-linking to form a film.

4. A method for repairing damage defects of an antigenic oxygen-resistant siloxane coating according to claim 1, characterized in that: In the step (2), the repair material is composed of dimethylsiloxane, perhydropolysilazane, nano-silicon oxide and nano-aluminum oxide powder diluted into a viscous solution, and the diluent is cyclohexane, toluene or n-butyl ether. Taking the total mass of the repair material as 100%, the mass percentage of each component is: Dimethicone 50%-60% Perhydropolysilazane 20%-30% Nano silicon oxide 5%-15% And nano alumina 5%-15%.

5. The method for repairing damage defects of an antigenic oxygen-resistant siloxane coating according to claim 1, characterized in that: The siloxane coating to be repaired is a siloxane coating deposited by plasma enhanced chemical vapor deposition.