Preparation And Research Of Polyurethane-Based Coating For Anti-Icing

As a common natural phenomenon,icing can bring many benefits to human beings,but the harm and loss caused by icing cannot be ignored.In order to reduce or avoid the harm caused by icing,people have adopted manual deicing,thermal deicing,and chemical deicing.However,these deicing methods are inefficient,high energy consumption,and poorly universal.As a consequence,the research of anti-icing materials is very essential to delay icing and improve deicing efficiency.The current anti-icing materials are grouped into three types in the light of the different media introduced between the ice layer and the substrate:The first type of surface is the superhydrophobic surface which can achieve delaying icing time and reducing ice adhesion strength via trapping air in surface textures of superhydrophobic surfaces.The second type of surface is the surface with the oil lubrication layer.It can reduce ice adhesion strength due to trapped liquid.The final type of surface is the surface with other trapped media.Aiming at the problems of the current anti-icing materials,this article has designed and fabricated the anti-icing materials to further improve the anti-icing properties,mechanical properties and durability of materials.1.For the superhydrophobic surface,the current fabrication methods have the problems of complicated operation,long time-consuming,difficult to prepare in a large area,and few researches on the temperature range in which superhydrophobic coating can decrease ice adhesion strength.Commercially available SiO2 nanoparticles and fluorosilicone resin have been used to fabricate polyurethane-based superhydrophobic coatings.This preparation method has the advantages of simple operation and large-area preparation.And the polyurethane-based superhydrophobic coating can effectively delay the freezing time of water droplets up to 4400 s at-15?,and has low ice adhesion strength at a temperature above-35?,showing excellent anti-icing performance.2.For the surface of the liquid lubricating layer,most of the matrix uses silicone elastomer(PDMS)as the carrier of the lubricating medium,which has the problems of poor mechanical properties and certain application restrictions.Therefore,in order to improve the mechanical properties of the coating of the liquid lubricating layer,this article uses liquid paraffin as the lubricating medium and polyurethane as the matrix to design and prepare a polyurethane-based lubricating layer coating.Compared with PDMS,the coating has excellent mechanical properties.The tensile strength of the substrate is about 18 MPa,which is about 4 times that of the PDMS substrate.At the same time,the surface of the coating has a low ice adhesion strength,only 43 kPa,and excellent anti-icing performance.3.Compared with the liquid lubricating layer,the liquid-like layer is connected to the substrate by chemical bonds,so it is not easy to run off.The unit is introduced into the matrix polyurethane in a covalent bond to prepare a polyurethane-based liquid layer coating.During 30 icing and deicing cycles,the coating's ice adhesion strength remained basically unchanged at only 57 kPa,demonstrating excellent anti-icing durability.At the same time,the coating uses polyurethane as the substrate,has excellent mechanical properties,tensile strength is about 12 MPa,3 times that of PDMS substrate,has a large application prospect.