Preparation Of Hydrophobic Fluorinated Polyurethane Coatings And Analysis Of Their Microstructure And Properties

Cavitation,wear,corrosion or their combined action lead to damage on the surface of water conservancy machinery,and then cause safety accidents,which has been a major obstacle to the economic and efficient operation of hydropower stations.Therefore,how to solve the problem of abrasion and corrosion on the surface of water conservancy machinery better,so as to achieve equipment safety,long life and high efficiency,is very urgent for researchers in related fields.According to the serious abrasion,corrosion problem on the surface of water conservancy machinery,this paper adopts two phenyl methane diisocyanate?MDI?and 2-perfluorooctyl ethyl alcohol?TEOH-8?reaction of fluorinated isocyanate compound,and then poly tetrahydrofuran?PTMEG?reaction of soft segment prepolymer,and then through the chain extender TEG chain extender and crosslinking reaction at the end of the reaction,using methanol terminated,finally using the optimized process parameters of spraying curing,prepared hydrophobic fluorinated polyurethane?FPU?coating.Hydrophobicity test shows that when the molar ratio of 2-perfluorooctyl ethyl alcohol?TEOH-8?and two phenyl methane diisocyanate?MDI?is 0.4⁰.6,the bonding force is 11.06MPa¹0.29MPa,the water absorption rate is 1.64%¹.27%,the water contact angle of 110.8¹20.3 degrees,and cohesive force and hydrophobic performance is very good.Erosion experiments shows that high polar fluorinated groups increased the molecular hard segment between the cohesive energy,the elastic modulus of hard segment area and tensile strength increased;in addition the elastic state of the soft segment phase can buffer the hard segment transfer external impact,abrasion resistance of FPU therefore to be improved.The artificial aging test shows that the fluorine groups in FPU-0.5 migrated to the surface and orderly stacked,effectively preventing moisture and other impurities from entering the coating,thus improving the anti-wear and anti-corrosion properties.Considering the application conditions of anti abrasion protective coating on the surface of the water conservancy machinery,when the molar ratio of TEOH-8and MDI is 0.5,the cavitation amount of FPU-0.5 was 0.9313×10^-3kg,lower than1.6834×10^-3kg of alloy steel?0Cr13Ni5Mo?substrate,anti abrasion ability are increased by44.68%.FPU-0.5 have adhesion,good hydrophobic properties and wear resistance,it can be used as anti wear and corrosion coating on the surface of the water conservancy machinery.