Preparation And Properties Of Silicone Based Self-deicing Coating

Ice forms easily on the pavement surfaces in winter,it greatly reduces anti-skidding performance of pavement,as a result of car accidents and subsequent traffic congestion.How to remove the ice and snow in time to ensure the safety of transportation and people's lives and properties has been the difficult problem to be solved by each country all along.As a kind of self-deicing technology,the self-deicing coating has attracted huge attention.At present,emulsified asphalt is usually used as the film carrier.However,emulsified asphalt based self-deicing coating has a harmful effect on friction coefficient and structure depth of asphalt pavement,it will greatly reduce anti-skidding performance of asphalt pavement.And the performance of the self-deicing coating is difficult to maintain for a long time,because the deicing additive embedded chloride salt will be dissolved by rain or melted snow easily.Thus,it is of great importance to develop appropriate deicing additive and film carrier to reduce the influence of self-deicing coating on the pavement structure,and ensure the long-term deicing performance.In this paper,one-component silicone and two-component silicone were prepared as the carrier of self-deicing coating,and the organics-coated NaCl deicing additive was prepared via the method of melt blending.A silicone based self-deicing coating was prepared by blending of silicone solution and organics-coated NaCl deicing additive.The adhesion force between silicone based coating and pavement,and the influence of coating on skid resistance were researched.The deicing performance and the corrosion to carbon steel of organics-coated NaCl were investigated.The deicing performance and the relationship between microstructure and deicing performance of self-deicing coating were evaluated.The main conclusions are as follows:?1?Comparedwithemulsifiedasphalt,one-componentsiliconeand two-component silicone coating behaved better adhesion performance with pavement.In addition,the adhesion performance between one-component silicone and pavement was the highest,the adhesion strength were 1.52MPa and 5.70MPa,when the pavement were asphalt concrete and cement concrete.Silicone based self-deicing coating had slight influence on friction coefficient and structure depth of asphalt pavement.When the amount of coating was 300 g/m²,The friction coefficient of emulsified asphalt coated asphalt concrete decreased by 23.0%,the construction depth decreased by 12.0%,the friction coefficient of one-component silicone and two-component silicone coated asphalt concrete only decreased by 10.4%and 13.4%,the construction depth only decreased by 6.1%and 9.1%.?2?The test of freezing point and relative deicing ability showed that,the deicing performance of organics-coated NaCl was relatively better,freezing point of 20wt%organics-coated NaCl solution was-14.1?,and the relative deicing performance was44%.The corrosion test indicated that the corrosion to carbon steel of organics-coated NaCl was significantly lower than NaCl,the corrosion rate of carbon steel by 20wt%NaCl solution was 1.80 mm·a^-1,but the corrosion rate of carbon steel by 20wt%organics-coated NaCl solution was only 0.65 mm·a^-1.?3?Compared with two-component silicone based self-deicing coating,one-component silicone based self-deicing coating could be better applied to pavement for deicing.To the one-component silicone based self-deicing coating,the freezing point of coating surface and the adhesion force between ice and coating decreased with the increase of the organics-coated NaCl content and the coating amount.However,when the content increased more than 6wt%or the coating amount increased more than 300g/m²,the deicing performance of self-deicing coating began to increase slowly.The freezing point and the adhesion force of the self-deicing coating with 6wt%organics-coated NaCl and 300g/m² coating were-5.2?and24.5N respectively.?4?Immersion in water had a greatly effect on the deicing performance of the self-deicing coating with NaCl,but it had less influence on the coating with organics-coated NaCl.The coating with organics-coated NaCl still had good deicing performance after immersion for 72h,the freezing point and the adhesion force of the self-deicing coating with 6wt%organics-coated NaCl and 300g/m² coating were-3.0?and 51.9N respectively,which indicated that it had good deicing durability.Compared with one-component silicone based self-deicing coating,the freezing point of two-component silicone based self-deicing coating was lower after immersion for72h,it had good deicing durability.But the adhesion force of two-component silicone based self-deicing coating was higher,it was more difficult to remove the ice when the temperature was lower than the freezing point.?5?Microstructure observation showed that,the deicing additive on the surface of coating was increasing in number with the increase of deicing additive content.The coating surface was completely covered with additive when the content of organics-coated NaCl was 6wt%.After immersion,NaCl was completely dissolved,and there were still many particles on the surface of the coating with organics-coated NaCl,which confirmed that the organics-coated NaCl had excellent resistance to water solubility.