第六章疏水材料超疏水PPT課件

1、logo1 supperrepellent material21 wettabilityvyoungs equation: cos=(sv sl)/ lv v hydrophobic: 90 ;v hydrophilic： 90 . wettability is a fundamental property of material surfaces3v water contact angle (wca) larger than 150 and extremely low wca hysteresis or sliding angle less than 10.superhydrophobici

2、ty4sliding anglevmg(sin)/ = (cosa-cosr)va advancing contact angle,vr receding contact angle, vm-the quality of water drop，vg-acceleration of gravity ，v-diameter of water drop，v-surface energy of water drop。vm，g， are constant ，then：vsincosa 5a wide spectrum of 789water collector in the desert10 11ant

3、ifouling coatingv the undesirable accumulation of microorganisms, plants, and animals on artificial surfaces immersed in sea water.v high frictional resistance and fuel consumption, due to generated roughness,v deterioration of the coating so that corrosion, discolouration, and alteration of the ele

4、ctrical conductivity of the material are favoured.12 vlow surface energy coatingfor mitigating marine biological foulingv antifouling coating13drag reduction1415self-cleaningmaterials16a17antifogging surfaces18局部局部放大放大oilwater separation19supperrepellent material in 20出淤泥而不染，出淤泥而不染，濯清漣而不妖。濯清漣而不妖。-宋宋

5、.周敦頤周敦頤愛蓮說愛蓮說21超疏水的荷葉和表面結(jié)構(gòu)（超疏水的荷葉和表面結(jié)構(gòu)（a)a)球形的水滴滴在荷葉表面（球形的水滴滴在荷葉表面（b)b)荷葉表面大荷葉表面大面積的微結(jié)構(gòu)（面積的微結(jié)構(gòu)（c)c)荷葉表面單個乳突（荷葉表面單個乳突（d d）荷葉表面的納米結(jié)構(gòu)）荷葉表面的納米結(jié)構(gòu)lotus effect22cicadas wingscicadas wingsv 蟬翼表面由規(guī)則排列的納米柱狀結(jié)構(gòu)組成納米柱的直徑大約在蟬翼表面由規(guī)則排列的納米柱狀結(jié)構(gòu)組成納米柱的直徑大約在80 nm80 nm，納米柱的間距大約在，納米柱的間距大約在180 nm180 nm規(guī)則排列納米突起所構(gòu)建的規(guī)則排列納米突起所構(gòu)

6、建的粗糙度使其表面穩(wěn)定吸附了一層空氣膜，誘導了其超疏水的性質(zhì)粗糙度使其表面穩(wěn)定吸附了一層空氣膜，誘導了其超疏水的性質(zhì)，從而確保了自清潔功能。，從而確保了自清潔功能。23butterfly wingsbutterfly wings24252、 the theoretics of supperrepellent materialwettabilitycassie modelwenzel modelyoungs equation26v for smooth, flat, uniform solid surface, the relationship between contact angle and

7、 surface energy can be described by yongs equation (thomas young, 1805 ) : : cos=(sv sl)/ lv interfacial tension: sv 、 sl 、 lv yongs equation2728functional surfacehydrophilic groups: oh、cho、 cooh、nh2hydrophobic groups： cnh2n+1、 ch=ch2、 c6h5、x、no2 cf329fluorinated polymer the reason of choosing fluor

8、osilicone low surface energy and high surface-active of cf3 group improves the adhesion and compatibility30self-assembly 31vfor smooth, flat, uniform solid surface, the highest contact angle is only 119。32real solid surface with concave-convex structurewenzel modelcassie modellogo33cos*= 1real conta

9、ct areaapparent contact arrealvslsv ) -r(=r cos wenzel model：34cos*=lvslsv ) -r(=r cos providing =110，if r0.53， * will be larger than 150wenzel model35cassie modellogo36cos= fcos+(1-f)cos180 = fcos+f-1area fraction f=a/(a+b)lets assume that =110，if f is less than 0.2, will be larger than 150.cassie

10、modelproviding ca between liqiud and air is 18037pan nano fiber materialpan nano fiber 39self-cleaning effectdirt4041roughening a hydrophobic materialfabricationsupperrepellent surfacemodifying a rough surfaces chemical 42turning a surface super-repellent even to completely wetting liquids tingyi“l(fā)e

11、o”liu,etal.,science, vol. 346, pp.1096-1100, 2014. 43template method44etching 45 v mccarthymccarthy等在聚四氟乙烯等在聚四氟乙烯 (ptfe)(ptfe)存在下存在下, , 用射頻等離子體刻蝕聚丙烯用射頻等離子體刻蝕聚丙烯 (pp)(pp)制備出粗糙表面。表面與水的前進角制備出粗糙表面。表面與水的前進角/ /后退角可達后退角可達 a/r = 172/169。利用射頻等離子體刻蝕法在不同刻蝕時間得到的聚丙烯掃描電子形貌圖利用射頻等離子體刻蝕法在不同刻蝕時間得到的聚丙烯掃描電子形貌圖: ( a) 0

12、min, ( b) 30 min, ( c) 60 min, ( d) 90 min,( e) 120 min, ( f) 180 min46chenchen等利用納米球刻蝕的方法首先得到了排列整齊的單層聚苯乙烯等利用納米球刻蝕的方法首先得到了排列整齊的單層聚苯乙烯 (ps)(ps)納米納米珠陣列珠陣列 , ,再用氧等離子體處理以進一步減小納米珠的尺寸從而得到粗糙表面再用氧等離子體處理以進一步減小納米珠的尺寸從而得到粗糙表面。在其表面覆蓋。在其表面覆蓋 20nm20nm厚的金膜并用十八硫醇厚的金膜并用十八硫醇(odt)(odt)進行修飾可以增強其疏水進行修飾可以增強其疏水性。通過調(diào)整性。通過調(diào)

13、整 psps納米珠的直徑納米珠的直徑 (440-190 nm)(440-190 nm)可以控制表面接觸角的大小可以控制表面接觸角的大小 (132-(132-168168 ) )。氧等離子體處理后的超疏水氧等離子體處理后的超疏水 psps納米珠陣列表面納米珠陣列表面48chemical vapor deposition 江雷等利用化學氣相沉積法江雷等利用化學氣相沉積法(cvd)在石英基底上制備了各種圖案在石英基底上制備了各種圖案結(jié)構(gòu)的陣列碳納米管膜結(jié)構(gòu)的陣列碳納米管膜, 結(jié)果表明結(jié)果表明, 水在這些膜表面的接觸角都大于水在這些膜表面的接觸角都大于 160, 滾動角都小于滾動角都小于5, 納米結(jié)構(gòu)

14、與微米結(jié)構(gòu)在表面的階層排列被認納米結(jié)構(gòu)與微米結(jié)構(gòu)在表面的階層排列被認為是產(chǎn)生這種高接觸角、低滾動角的原因。為是產(chǎn)生這種高接觸角、低滾動角的原因。494 research planvin order to fabricate superhydrophobic or superhydrophilic surfaces based on sub-micron structures, i think my research in uw can be divided into three 50vfirstly, the fabrication of artificial structured surfa

15、ce. vseveral artificial structured surfaces have been disgined. vif these nanopillar and mushroom shaped nanopillars array with piece of 10 mm10 mm can be prepared by electroplate copper or nickel nanopillars?52vsecondly, modify its components by surface fluorination. 53vlastly, the fabrication of hierarchical structures. if the property of above structured surface after surface fluorination can not meet superhydrophobic or superhydrophilic requirement, i will increase surface roughness by preparing hierarchical structures on abov