疏水材料-超疏水.ppt

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1、Supperrepellentmaterial1WettabilityYoung’sequation:cosθ=(γSV–γSL)/γLVHydrophobic:θ›90°;Hydrophilic：θ‹90°.WettabilityisafundamentalpropertyofmaterialsurfacesWatercontactangle(WCA)largerthan150°andextremelylowWCAhysteresisorslidinganglelessthan10°.Super

2、hydrophobicitySlidinganglemg(sinα)/ω=γ(cosθa-cosθr)θa–Advancingcontactangle,θr–Recedingcontactangle,m-Thequalityofwaterdrop，g-Accelerationofgravity，ω-Diameterofwaterdrop，γ-SurfaceEnergyofwaterdrop。m，g，ω，γareconstant，then：sinα∝cosθa–cosθr.Awidespectrum

3、ofapplicationssoysauceWatercollector inthedesertAntifoulingcoatingTheundesirableaccumulationofmicroorganisms,plants,andanimalsonartificialsurfacesimmersedinseawater.Highfrictionalresistanceandfuelconsumption,duetogeneratedroughness,Deteriorationofthec

4、oatingsothatcorrosion,discolouration,andalterationoftheelectricalconductivityofthematerialarefavoured.LowsurfaceenergycoatingformitigatingmarinebiologicalfoulingAntifoulingcoatingDragreductionSelf-cleaningmaterialsAntifrostAntifoggingsurfaces局部放大Oil−

5、waterseparationSupperrepellentmaterialin nature出淤泥而不染，濯清涟而不妖。--宋.周敦颐《爱莲说》超疏水的荷叶和表面结构（a)球形的水滴滴在荷叶表面（b)荷叶表面大面积的微结构（c)荷叶表面单个乳突（d）荷叶表面的纳米结构LotuseffectCicada'swings蝉翼表面由规则排列的纳米柱状结构组成．纳米柱的直径大约在80nm，纳米柱的间距大约在180nm．规则排列纳米突起所构建的粗糙度使其表面稳定吸附了一层空气膜，诱导了其超疏水的性质，从而确

6、保了自清洁功能。Butterflywings2、ThetheoreticsofSupperrepellentmaterialWettabilityCassiemodelWenzelmodelYoung’sequationForsmooth,flat,uniformsolidsurface,therelationshipbetweencontactangleandsurfaceenergycanbedescribedbyYong’sequation(ThomasYoung,1805):cosθ=(γ

7、SV–γSL)/γLVInterfacialtension:γSV、γSL、γLVYong’sequationHydrophobicsurfaceThesurfacefreeenergyofmaterialsisrelatedtothespeciesandtheconcentrationofthefunctionalsurfacegroupsFunctionalsurfaceHydrophilicgroups:—OH、—CHO、—COOH、—NH2Hydrophobicgroups：—CnH2n+

8、1、—CH=CH2、—C6H5、—X、—NO2—CF3FluorinatedpolymerCH2(36dyncm-1)>CH3(30dyncm-1)>CF2(23dyncm-1)>CF3(15dyncm-1)ThereasonofchoosingfluorosiliconeLowsurfaceenergyandhighsurface-activeofCF3groupImprovestheadhesionandcompatibilityself-assemblyForsmooth,f