Facile Fabrication Of Hydrophobic Surface And Its Applications

Superhydrophobic surface have a wide range of practical values and business prospects in waterproof,self-cleaning,bacteriostasis,selective adsorption and drag reduction.Low surface energy materials and surface rough structure are the two major factor of superhydrophobic surface.However,the preparation of surface rough structure can increase surface area and surface energy,which goes against the aim of low surface energy materials.It is generally believed that the two process cannot be accomplished in one step.It results in multiple steps including low surface energy materials and the formation of surface rough structure are required to create hydrophobic structure in existing commercial technique.As a result,most techniques are too complex to industrialize.N-octyltriethoxysilane and tetrabutyl titanate are active ingredients in the paper.Then,the modification of porous building materials,filter paper and nanometer titania was researched.(Super)Hydrophobic surface was formed in a step at room temperature and pressure.The specific research content and results are as follows:The porous building materials including granite,wood,concrete were modified.The change of contact angle and water absorption were tested.The water absorption of granite,wood,concrete reduced 87.53%,27.17%,91.47%respectively after modification.And the contact angle were 140.5°?132.70°?141.3°,respectively.The filter paper was modified.The wettability,separation efficiency of oil/water,durability and corrosion resistance were tested.The surface contact angles of filter paper was 153.6° after treatment,which met the standard of superhydrophobicity.The surface contact angles of superhydrophobic filter paper still remained above 145°after the corrosive test.Meanwhile,the efficiency of oil-water separation all reached as high as above 88%for different oil-water systems.The superhydrophobic filter pape exhibited excellent durability.The hydrophobic modification of nanometer titanium dioxide was implemented by immersion method.The photocatalytic activity was evaluated by photocatalytic degradation of methylene blue.The modification techniques had no affection on the morphology,crystal form and spectral characteristics of nanometer titanium dioxide.The photocatalytic efficiency and reaction kinetic constant of nanometer titanium dioxide increased 30.0%and 109.0%,respectively,after modification.The cohydrolysis of n-octyltriethoxysilane and tetrabutyl titanate can happen under the natural condition.The hydrolyzation product of tetrabutyl titanate are amorphous nanometer titanium dioxide particles,which increases the roughness of the substrate surface.The hydrolyzation of n-octyltriethoxysilane generate reactive hydroxyl groups,which can be accelerated in the presence of titanium dioxide.On account of the condensation of hydroxyl groups,the network structure can be formed on the substrate surface,which will lower the relative surface energy of material.The coupling reaction between n-octyltriethoxysilane and tetrabutyl titanate is the main factor for the formation of hydrophobic layer.