Research On Mask Chemical Processing And Application Of Patterns With Extreme Wettability

Extremely wettable patterned surface has broad application prospects in bioengineering,fog collection,medical medicine and other fields due to its excellent characteristics of self-cleaning,corrosion resistance and anti-icing.However,the current methods for preparing extreme wettability patterns are complicated and versatile,and in particular for a variety of metal substrates in the engineering field,there is a lack of a general method for preparing extremely wettable patterns at low cost and high efficiency.The paper proposes a mask-assisted two-step method without special modification to prepare extreme wettability patterns on various substrates such as aluminum,titanium,zinc,magnesium alloy,stainless steel,etc.,and the extreme wettability prepared by this method.The patterned surface was applied to the fog collection test to study the fog collection efficiency of different surfaces.The main contents include:Aiming at the disadvantages of high cost and poor applicability of traditional preparation methods,a mask-assisted dual chemical processing method was proposed to prepare superhydrophobic/superhydrophilic wettability patterns on the surface of metal substrates.The superhydrophobic region is first prepared by mask-assisted chemical processing and fluorosilane modification,and then the superhydrophilic pattern is prepared by dropping the reaction solution into the original mask covering region.The method does not require large test equipment and special modification,and can quickly prepare a superhydrophobic/superhydrophilic wettability pattern.In order to prepare an extremely wettable pattern on the surface of the aluminum substrate,the masked aluminum plate is placed in an aqueous solution of copper chloride to etch the micro/nano structure,and the fluorosilane is modified to obtain a superhydrophobic surface.Then,the area covered by the original mask is etched into a superhydrophilic region by a method of dropping an etching solution by a syringe,and the etching time is 20 s.After dual chemical etching,an extremely wettable pattern containing superhydrophobic regions and superhydrophilic regions was successfully prepared on the surface of the aluminum plate.The prepared aluminum sheet is placed in water to obtain the superoleophobic/superlipophilic wettability pattern.Finally,the wettability,microstructural and chemical composition of the prepared patterned surface is characterized.In order to verify the versatility of the dual chemical processing method on various metal surfaces,the corresponding processing solution and ambient temperature were selected,and the extreme wettability patterns were prepared on the four metal surfaces of titanium,stainless steel,zinc and magnesium alloy separately.The patterned surfaces are characterized by microstructure and chemical composition.In order to study the application properties of the prepared extremely wet-patterned surface in fog collection,the fog collection efficiency of the common surface of the aluminum substrate,superhydrophilic,superhydrophobic and patterned surfaces was analyzed.The results show that the extremely wettable surface is higer efficient than the ordinary surface collection,while the patterned surface with both superhydrophilic and superhydrophobic areas has the highest collection efficiency.The superhydrophobic surface with the same area of the superhydrophilic pattern of the five-pointed star was prepared on the surface of aluminum,zinc and magnesium alloy by secondary chemical processing method.The results showed that the fog collection efficiency of different metal patterned surfaces was quite different.