Preparation Of Hydrophobic/Superhydrophobic Composite Coating And Anti-icing Performance

Icing is a natural phenomenon on solid surfaces,which is commonly found in aerospace,transportation and other aspects.At present,hydrophobic/superhydrophobic coatings have become one of the most active research topics in the field of anti-icing due to excellent icephobicity.However,the development and application of the coating are greatly limited by the failure of anti-icing under ultra-low-temperature and the insufficient deicing and durability under mechanical damage.In this subject,firstly,the research on the ultra-low-temperature deicing properties of the hydrophobic nanoparticle-grease composite coating was carried out to solve the problem of difficult deicing under ultra-low-temperature conditions;Secondly,the preparation and particle size refinement of the polyhedral oligomeric silsesquioxane coating was carried out to effectively improve the deicing durability of the coatings.The main research contents are as follows:The nanoparticle-grease composite coating with excellent hydrophobic-lipophilic properties was obtained by combining the 7015 high-low-temperature grease with hydrophobic-lipophilic nanoparticles and using large-scale preparation processes such as brushing and rolling.Studies have shown that the reasonable mass ratio of powder and grease(hydrophobic-lipophilic nanoparticles:7015 high-low-temperature grease)is 2.5:100.The ice adhesion strength of the coating is 7.6 KPa at-20?;The ice adhesion strength is 24.9 KPa at-100?,which is even better than the reported ice adhesion strength of the liquid layer generators at-60?.In addition,the coating has excellent antifrosting performance regardless of whether it is at-20? or-100?.The deicing and durability of the polyhedral oligomeric silsesquioxane coating is strengthened by the controlled variable method.The experimental results have shown that the coating prepared by the volume ratio of highly crosslinked coating: high-concentration superhydrophobic nano-coating =1:1 has excellent deicing and durability.The ice adhesion strength is 29.6 KPa after 300 times of friction by the friction testing machine under a load of 1000 g,which meets the requirements of deicing performance after abrasion.In addition,the ice adhesion strength of the coating can still maintain 25.5 KPa under the coordinated destruction of 700 finger rubbing and 26 icing/deicing cycles.More importantly,through the analysis of the deicing test results of each stage,it is found that the polyhedral oligomeric silsesquioxane coating has excellent deicing performance,which should meet two conditions: the roughness is less than 50 nm and the contact angle is more than 135°.This provides theoretical guidance and design ideas for the research of anti-icing coating.The acidic superhydrophobic nano-coating is prepared by the sol-gel method.In the acetic acid system of pH 3,the coating prepared by 9 nm spherical silica sol and 15 nm pearl chain silica sol has excellent superhydrophobicity.The coating was prepared by the volume ratio of highly crosslinked coating: acidic high-concentration superhydrophobic nano-coating = 1:1,and its deicing and durability was further improved.The ice adhesion strength is 31.1 KPa after 700 times of friction under a load of 1000 g by friction testing machine;the ice adhesion strength after wearing 60 cycles by abrasion tester under a load of 250 g is 28.4 KPa,which meets the requirements of deicing performance.In addition,the coating has excellent low-temperature environmental stability.At-10?,the droplet doesn't freeze within 2663 s,and freezes completely after 98 s;at-20?,the coating has excellent anti-frosting performance;at 2?,the coating has excellent anti-condensation performance.