Design And Preparation Of Porous Micro-nano Macro Surfaces And Its Anti-icing Performance

People's daily life was directly affected by icing,a common phenomenon in nature,especially in the fields of road traffic,air transportation,and power transmission lines.However,the widely used deicing methods such as snow melting agents,mechanical deicing methods,and electric heating methods have many disadvantages,such as polluting the environment,high energy consumption,low efficiency,and consuming many resources.As a passive anti-icing method,the anti-icing surface has the advantages of less manual operation and low energy consumption,and it is the development direction of anti-icing technology.The researchers conducted in-depth research on the preparation process,anti-icing performance,and durability of the anti-icing coatings.Inspired by the lotus leaf and antifreeze protein,the surface covered by open-mouth hollow spheres with micro-nano structures formed by POSS self-assembly was prepared on the substrate by spraying,and the hydrophilic ice nucleation inhibitor PVA was further sprayed to prepare an anti-icing coating.The contact angle,freezing temperature of droplets,and ice adhesion strength were used to evaluate the anti-icing performance of the coating.The results showed that the micro-nano structure surface constructed by hydrophobic POSS had synergistic effects with hydrophilic icing inhibitor PVA:PVA covered heterogeneous nucleation sites to reduce the probability of ice formation;the micro-nano structure surface reduced the actual contact area and the surface and then hindered heat conduction.The best anti-icing performance was obtained by adjusting the particle distance and PVA content with the contact angle of 149.3°,the freezing temperature of-22.6?,and the ice adhesion strength of 69.1 kPa.The self-lubricating nanometer thickness MOF(Uio-66-NH2)coating(SLNTMC)was prepared on the surface of the polypropylene film by the solvothermal method based on the bionic principle of nepenthes.The effects of the surface morphology of the coating and the molecular weight of silicone oil on the anti-icing performance were studied through SEM,FT-IR,XRD,and other instrumentals as well as anti-icing performance such as contact angle,freezing temperature,and ice adhesion strength.The results showed that silicone oil as a low surface energy lubricant can not only reduce the force between ice and coating but also cover part of the heterogeneous nucleation sites on the surface and reduce the freezing temperature.The contact angle of the anti-icing coating with water was 133.2°,the freezing temperature was-26.9?,and the ice adhesion was 9.4 kPa.SLNTMC showed better durability compared with lubricant infused nanometer thickness MOFs Coating(LINTMC)due to chemical grafting.Based on the above research,silicone oil was synthesized directly on the MOF surface by the in-situ synthesis method.And the increase of grafting amount of silicone oil enhanced the anti-icing performance of SLNTMC:the contact angle with water was 137.3°,the freezing temperature was-29.6?;and the ice adhesion strength was 9.1 kPa.In this paper,PVA-POSS/PDMS coating and SLNTMC coating were prepared by constructing and modifying the surface of micro-nano structures,which provided a new idea for the design and preparation of passive anti-icing coating and the improvement of anti-icing performance.