黃穎芬

基于液狀PDMS的共價鍵合型動態(tài)雙疏表面及其自清潔功能

黃穎芬

（泉州醫(yī)學(xué)高等專科學(xué)校 藥學(xué)院，福建 泉州 362011）

通過簡便的方法在惰性基底上構(gòu)建具有穩(wěn)定動態(tài)雙疏性能和自清潔功能的表面。利用非化學(xué)計量比的硅橡膠前體表面具有的硅氫鍵和單乙烯基封端聚二甲基硅氧烷之間的氫化硅烷化反應(yīng)，在惰性不銹鋼基底上制得透明、平滑、無氟、穩(wěn)定的基于液狀PDMS的共價鍵合型動態(tài)雙疏表面CBDOS（Covalently-Bonded Dynamically-Omniphobic Surface）。通過ATR-FTIR和XPS表征表面的化學(xué)組成，通過AFM和FE-SEM分析表面形貌，通過液滴形狀分析儀測定表面的接觸角CA值、滑動角SA值和接觸角滯后CAH值。分析證實液狀PDMS已被成功鍵合在CBDOS表面，且表面具有納米級粗糙度，均方根粗糙度q僅為0.964 nm。同時，表面具有卓越的動態(tài)雙疏性能和良好的儲存穩(wěn)定性，水的SA值為2.20°、CAH值為1.75°，正十六烷的SA值為7.33°、CAH值為7.34°。這使CBDOS對極性或非極性、相溶或不相溶、水溶性或油溶性的污染物都展現(xiàn)出良好的自清潔功能。CBDOS極端均勻平滑的表面形貌及其上單端共價鍵合的液狀PDMS所具有的高度移動性和柔韌性，使其獲得卓越的動態(tài)雙疏性能和自清潔功能。本方法簡便，條件溫和，對環(huán)境無污染，并可拓展應(yīng)用于各類基底。同時，由于液狀PDMS是共價鍵合在材料表面，可有效增強動態(tài)雙疏表面的穩(wěn)定性。

聚二甲基硅氧烷；液狀聚合物；氫化硅烷化；共價鍵合；動態(tài)雙疏；自清潔

材料表面的抗?jié)櫇裥袨槭且环N重要的界面現(xiàn)象，因其在自清潔[1-6]、防污染[7-8]、防腐蝕[9-13]、防覆冰[13-17]、減阻[18-20]等諸多領(lǐng)域應(yīng)用前景廣闊，近年來，吸引了越來越多研究人員的關(guān)注和重視。早期對材料表面抗?jié)櫇裥阅艿难芯恐饕且越佑|角CA（Contact Angle）為評判標(biāo)準(zhǔn)，即在靜態(tài)條件下，以CA值90°作為親液和疏液表面的界線?？紤]到界面間分子的相互作用，該界線現(xiàn)已降低至65°[21-22]。研究還發(fā)現(xiàn)，將CA值相同的材料表面同時傾斜同樣的角度，有的表面會使液滴滾落或滑落，而有的表面則使液滴粘附。因此，要全面地評價材料的抗?jié)櫇裥阅?，單純考察靜態(tài)接觸角是不充分的，還應(yīng)分析表面的動態(tài)抗?jié)櫇裥袨?。相關(guān)研究報道中將材料表面的疏液性能分為靜態(tài)和動態(tài)疏液性能，并以滑動角SA（Sliding Angle）和接觸角滯后CAH（Contact Angle Hysteresis）作為表征表面動態(tài)疏液性能的關(guān)鍵指標(biāo)[23-24]。材料表面的SA值和CAH值越小，表明其對液滴的粘附力越小，這樣的表面越有利于液滴滾落或滑落，從而實現(xiàn)動態(tài)疏液和自清潔等功能[25-26]。據(jù)文獻報道，當(dāng)極性和非極性的液滴在材料表面的SA值和CAH值都小于10°時，一般就認為該表面具備卓越的動態(tài)雙疏性能[23,27-29]。目前，針對動態(tài)雙疏表面的研究還較少。

彈尾蟲[30-33]和豬籠草[34-35]為了適應(yīng)惡劣的生存環(huán)境，進化出了具有動態(tài)雙疏性能的表皮結(jié)構(gòu)和口緣區(qū)結(jié)構(gòu)。受它們的啟發(fā)，研究人員開發(fā)了2種實現(xiàn)表面動態(tài)雙疏性能的策略。一種是構(gòu)建具有特定微納米粗糙結(jié)構(gòu)，特別是凹角幾何結(jié)構(gòu)的表面[36-40]。這種策略的難點在于其所需構(gòu)建的拓撲結(jié)構(gòu)復(fù)雜、精細，因此對儀器、技術(shù)和成本的要求較高。同時，當(dāng)表面遭受外力作用時，多尺度微觀結(jié)構(gòu)易被破壞，從而失去疏液性能，因此該策略不適于規(guī)?；茝V應(yīng)用。另一種策略是在微納米多孔結(jié)構(gòu)表面灌注潤滑液，用低表面能的液體替代多孔結(jié)構(gòu)中的氣體，形成光滑、均一的抗?jié)櫇癖砻?。該方法雖然克服了多級粗糙結(jié)構(gòu)易磨損、不耐壓等弊端[41-45]，但是潤滑液只是通過弱的毛細作用力保持在底層多孔結(jié)構(gòu)中，因此常常會因為蒸發(fā)或液滴挾帶等原因而使?jié)櫥簱p失，以致失去動態(tài)雙疏性能。同時，為了盡量減小材料的表面能，進而實現(xiàn)優(yōu)秀的抗?jié)櫇裥阅埽鲜?種策略大多需要修飾或灌注含氟化合物，這將潛在一定的污染性。

為了克服上述缺陷，研究人員提出了一種獨特的新策略，即將液狀聚合物共價鍵合到材料表面，利用表面平滑均勻的形貌以及液狀聚合物高度的移動性和柔韌性實現(xiàn)卓越的動態(tài)雙疏性能[46-48]。聚二甲基硅氧烷（PDMS）具有低表面能、低玻璃化轉(zhuǎn)變溫度，同時主鏈上的—Si—O—Si—重復(fù)單元賦予其良好的移動性和柔韌性，因此在室溫下仍然保持優(yōu)異的熔融狀態(tài)，可以看作液狀聚合物，是現(xiàn)階段構(gòu)建此類表面最適宜的聚合物之一[23,49]。此外，該策略將液狀聚合物共價鍵合到基底表面，可有效增強動態(tài)抗?jié)櫇癖砻娴姆€(wěn)定性。但是，已有文獻報道中的共價鍵合方式很有限，大多是將液狀聚合物直接鍵合在硅片等具備反應(yīng)活性的基底表面[23,27,47]，這將大大限制該方法在普通基底材料上的應(yīng)用。因此，有必要探索一種可以在惰性基底表面實現(xiàn)該策略的鍵合方法。本研究以非化學(xué)計量比的Sylgard 184液體硅橡膠為前體，通過其表面具有的硅氫鍵和單乙烯基封端PDMS之間的氫化硅烷化反應(yīng)，在惰性不銹鋼基底表面形成了透明、平滑、無氟、穩(wěn)定的共價鍵合型動態(tài)雙疏表面CBDOS（Covalently-Bonded Dynamically-Omniphobic Surface）。

1 試驗

1.1 動態(tài)雙疏表面的制備

將Sylgard 184（美國Dow Corning）A、B組分按質(zhì)量比（1∶10或1∶2）混合，在頂置式機械攪拌器（德國IKA）作用下以1800 r/min攪拌15 min，隨后抽真空直到?jīng)]有明顯氣泡。將足量的混合物滴加于預(yù)處理（首先用砂紙打磨不銹鋼片表面，隨后清洗干凈，再置于丙酮中超聲，最后用純化水充分洗凈，并烘干）后的2 cm×2 cm不銹鋼片，置于臺式勻膠機（北京賽德凱斯KW-4B型）上，以300 r/min旋涂10 s，再將轉(zhuǎn)速增大到800 r/min旋涂40 s。處理后的樣品再一次真空脫泡，隨后加熱硫化，分別得到2種質(zhì)量比的硅橡膠。其中，質(zhì)量比為1∶10的硅橡膠標(biāo)記為S184，質(zhì)量比為1∶2的硅橡膠標(biāo)記為pre-CBDOS。

將單乙烯基封端聚二甲基硅氧烷（MVT-PDMS，江蘇科幸VM500）和鉑金催化劑（江蘇科幸CAT- Pt015）混合均勻，再將pre-CBDOS浸沒于該混勻體系中，于50 ℃恒溫箱中反應(yīng)5 h。隨后取出，豎直靜置24 h后，依次用丙酮、乙醇及純化水充分清洗樣品，直至在洗滌溶劑中檢測不到MVT-PDMS，以除去表面殘留的未鍵合的MVT-PDMS。最后，將樣品于50 ℃下干燥數(shù)小時，即制得基于液狀PDMS的共價鍵合型動態(tài)雙疏表面，標(biāo)記為CBDOS。

1.2 表征與性能測試

1）通過傅里葉紅外光譜儀（美國Thermo-Fisher Nicolet 5700型）ATR法分析不銹鋼基底、S184、pre-CBDOS和CBDOS中基團的變化。

2）通過X射線光電子能譜儀（美國Thermo- Fisher Escalab 250Xi型）分析pre-CBDOS和CBDOS的表面原子組成。

3）通過場發(fā)射掃描電子顯微鏡（日本電子株式會社JSM-7500F型）分析CBDOS的表面形貌。用導(dǎo)電膠帶將待測樣品固定于樣品臺上，使用離子濺射儀（中鏡科儀）將導(dǎo)電金膜沉積于樣品表面。

4）通過原子力顯微鏡（美國Veeco Nanoscopy ⅢA型）分析不銹鋼片和CBDOS的表面形貌，并計算均方根粗糙度。工作模式：輕敲；探針型號：FESP-V2；掃描范圍：2 μm×2 μm。

5）通過液滴形狀分析儀（德國KRUSS DSA 25型）分析、測定不銹鋼片和CBDOS表面的接觸角CA值、滑動角SA值、前進角A、后退角R和接觸角滯后CAH值，測試液體為極性的純化水和非極性的正十六烷。CA值測試：將2 μL測試液滴置于水平樣品表面，待數(shù)值穩(wěn)定后記錄數(shù)據(jù)，絕對誤差為±2.00°。SA值測試：將30 μL純化水或5 μL正十六烷置于水平樣品表面，隨后緩慢旋轉(zhuǎn)樣品臺，直至測試液滴開始滑動，讀取此時樣品臺傾斜的角度，即SA值，水SA值的絕對誤差為±0.50°，正十六烷SA值的絕對誤差為±1.00°。A和R測試：采用靜滴法，液滴注入（A）或抽出（R）的速度為0.02 mL/min，絕對誤差為±2.00°。CAH值通過計算A和R的差值得到。每個樣品至少平行測定3個不同區(qū)域，最終測定結(jié)果選用各次測定值的平均值。

2 結(jié)果及分析

2.1 動態(tài)雙疏表面的表征

將Sylgard 184雙組分以質(zhì)量比A∶B=1∶10均勻混合后，A組分聚甲基氫硅氧烷中的硅氫鍵可與B組分乙烯基聚二甲基硅氧烷中的乙烯基發(fā)生交聯(lián)反應(yīng)，從而完全固化。若提高A組分的比例至A∶B= 1∶2，則制得的pre-CBDOS中將有硅氫鍵剩余。體系中剩余的硅氫鍵可在鉑金催化劑的作用下與MVT-PDMS中的乙烯基進行氫化硅烷化反應(yīng)，從而將液狀PDMS鏈共價鍵合到pre-CBDOS表面，制得基于液狀PDMS的共價鍵合型動態(tài)雙疏表面CBDOS，如圖1所示。

圖1 CBDOS制備

通過ATR-FTIR表征不銹鋼基底、S184、pre- CBDOS和CBDOS中特定基團的變化，并監(jiān)測氫化硅烷化反應(yīng)過程，如圖2所示。結(jié)果表明，不銹鋼基底曲線中未見明顯的有機物特征吸收峰，而S184、pre-CBDOS和CBDOS 3條曲線中都包含PDMS的典型特征峰。其中，Si—O—Si的伸縮振動峰為位于1018、1085 cm–1的雙峰，SiMe2中的—CH3對稱和非對稱變形振動峰分別位于1259、1409 cm–1處，而—CH3的非對稱和對稱伸縮特征峰則在2906、2962 cm–1處。與S184曲線相比，由于A組分質(zhì)量比的增大，pre-CBDOS曲線在2160 cm–1處出現(xiàn)了明顯的Si—H峰，表明體系中存在可與MVT-PDMS發(fā)生反應(yīng)的Si—H。隨著氫化硅烷化反應(yīng)的進行，CBDOS曲線上并未檢測出Si—H峰。這表明體系中的Si—H已完全被消耗，通過其與MVT-PDMS中的乙烯基之間的共價結(jié)合，已將PDMS鏈成功鍵合到pre-CBDOS表面，從而形成了CBDOS動態(tài)雙疏表面。

圖2 不銹鋼基底、S184、pre-CBDOS和CBDOS的ATR-FTIR譜圖

采用XPS測試共價鍵合液狀MVT-PDMS前后pre-CBDOS和CBDOS表面的化學(xué)組成，數(shù)據(jù)見表1。通過理論計算，MVT-PDMS中C、Si和O的原子分數(shù)分別為50.21%、24.84%和24.95%。由此可見，CBDOS中C、Si和O的原子組成與MVT-PDMS的理論值基本契合，而pre-CBDOS中C、Si和O的原子組成與MVT-PDMS的理論值存在明顯差異。因此，XPS測試結(jié)果進一步證實了液狀MVT-PDMS鏈已被成功鍵合到pre-CBDOS表面。低表面能的液狀MVT-PDMS鏈具有高度的移動性和柔韌性，有利于減小液滴與CBDOS表面之間的摩擦因數(shù)[50]。同時，PDMS鏈與表面的共價鍵合將有效增強表面的穩(wěn)定性。

利用AFM和FE-SEM分析表征CBDOS的表面形貌，如圖3所示。結(jié)果表明，CBDOS表面相當(dāng)均勻平滑，沒有明顯的聚集或缺陷。同時，AFM數(shù)據(jù)顯示，基底不銹鋼片的均方根粗糙度q為5.245 nm，而在其表面構(gòu)建CBDOS后，q降至0.964 nm。均勻平滑的表面形貌可以減小液滴在表面移動時所需克服的阻力，從而獲得較小的SA值和CAH值，有助于CBDOS表面實現(xiàn)卓越的動態(tài)抗?jié)櫇裥阅芗白郧鍧嵐δ堋?/p>

表1 pre-CBDOS和CBDOS的表面原子組成

Tab.1 The surface atomic composition of pre-CBDOS and CBDOS　 at.%

圖3 CBDOS表面的AFM和FE-SEM形貌

2.2 動態(tài)雙疏表面的抗?jié)櫇裥阅?/h3>

以極性的純化水和非極性的正十六烷為測試液滴，測定、分析并比較了不銹鋼基底和CBDOS表面的抗?jié)櫇裥阅?，如圖4所示。結(jié)果表明，CBDOS表面具有靜態(tài)疏水親油、動態(tài)雙疏的性能。預(yù)處理過程在一定程度上改變了不銹鋼片的表面形貌，使其水CA值略有變化。而CBDOS表面的水CA值高于不銹鋼表面，表明其靜態(tài)疏水性能優(yōu)于基底不銹鋼片。由于水的表面能較高，正十六烷的表面能較低，因此不論是不銹鋼片，還是CBDOS表面，都具有較小的正十六烷CA值。但CBDOS表面的正十六烷CA值仍略高于不銹鋼表面，證明其靜態(tài)雙疏性能均強于不銹鋼片。進一步考察表面的動態(tài)抗?jié)櫇裥阅馨l(fā)現(xiàn)，不論是極性的水，還是非極性的正十六烷，在CBDOS表面都顯示出很小的SA值和CAH值。其中，水SA值僅為2.20°，CAH值僅為1.75°，相比不銹鋼表面分別降低了95.25%和96.16%；正十六烷SA值為7.33°、CAH值為7.34°，相比不銹鋼表面分別降低了14.17%和13.14%。因此，通過在不銹鋼表面構(gòu)建CBDOS，可有效提高材料表面的抗?jié)櫇裥阅?。CBDOS表面的水SA值和CAH值均小于3°，正十六烷SA值和CAH值均小于8°，表明表面具有卓越的動態(tài)雙疏性能，與相關(guān)文獻報道[27,50,51]的結(jié)論一致。

圖4 不銹鋼基底和CBDOS表面的抗?jié)櫇裥阅?/p>

將CBDOS表面于常溫常壓下靜置75 d后，再次測試其抗?jié)櫇裥阅?，?shù)據(jù)見表2。分析比較發(fā)現(xiàn)，液滴在CBDOS表面呈現(xiàn)的CA值、SA值和CAH值變化都很小，極性的水和非極性的正十六烷SA值、CAH值依然都小于8°，表明CBDOS表面具有良好的儲存穩(wěn)定性和穩(wěn)定的動態(tài)雙疏性能。

表2 CBDOS表面的抗?jié)櫇裥阅埽o置75 d后）

Tab.2 The anti-wettability of CBDOS (deposited for 75 days)

液滴之所以能夠容易地從CBDOS表面滑落，可能存在以下3個主要原因[23,27,49,50,52]：第一，CBDOS表面相當(dāng)均勻平滑，具有納米尺度的表面粗糙度，這將十分有利于減小液滴的SA值和CAH值；第二，常溫下，聚二甲基硅氧烷PDMS為液狀聚合物，其主鏈中的—Si—O—Si—重復(fù)單元具有非常強的柔性，共價鍵合到pre-CBDOS表面后，依然具有高度的移動性和柔韌性，使CBDOS表面好似錨定了一層潤滑液，形成了穩(wěn)定的液狀聚合物表層；第三，氫化硅烷化反應(yīng)發(fā)生后，單乙烯基封端的MVT-PDMS鏈僅有一端被共價鍵合在pre-CBDOS表面，這將進一步有利于表層液狀PDMS保持非常高的移動性和柔韌性。因此，當(dāng)液滴在均勻平滑的CBDOS表面移動時，具有高度移動性和柔韌性的液狀PDMS鏈可以有效地降低液滴前進或者后退所需的能壘，得到非常小的SA值和CAH值，實現(xiàn)表面的動態(tài)雙疏性能及自清潔功能。

2.3 動態(tài)雙疏表面的自清潔功能

不論是極性的還是非極性的液滴，在CBDOS表面都顯示出很小的SA值和CAH值，這將有助于液滴順利地從CBDOS表面滑落，實現(xiàn)自清潔功能。研究選用了生活中常見的8種液體模擬污染物，以便全面地考察CBDOS表面的動態(tài)抗?jié)櫇裥阅芎妥郧鍧嵐δ埽兓?、可樂、茶、食用油、咖啡、醋、醬油和黃酒等。觀察50 μL各種污染物液滴在基底不銹鋼片和CBDOS表面的形態(tài)，如圖5所示。結(jié)果表明，所有的污染物液滴在CBDOS表面都比在不銹鋼片表面更為集中，也就是說液滴在CBDOS表面所具有的CA值都比在不銹鋼表面的大，表明CBDOS的靜態(tài)疏液性能優(yōu)于基底不銹鋼片。

將50 μL不同污染物液滴分別置于不銹鋼片和CBDOS表面，隨后傾斜表面至10°，觀察并比較液滴在不同表面的滑動情況，依次記錄于圖6中。由圖6a可以看出，60 s后，污染物液滴全都仍舊粘附在不銹鋼片表面，大部分液滴形狀變得更加分散，而位置幾乎沒有變化。圖6b則顯示，位于CBDOS表面的污染物液滴全都順利滑落，并且液滴滑過后，表面保持干燥、潔凈，沒有明顯痕跡，表明液滴在表面沒有發(fā)生拖尾或粘附。由此可見，CBDOS表面具有全面的動態(tài)抗?jié)櫇裥阅?，這將使其在實際應(yīng)用中，對極性或非極性、相溶或不相溶、水溶性或油溶性的污染物都展現(xiàn)出顯著的動態(tài)雙疏和自清潔功能。

進一步模擬戶外條件考察CBDOS表面的自清潔功能。圖7a以連續(xù)的水流模擬雨水沖刷傾斜10°放置的CBDOS表面，結(jié)果表明，連續(xù)的水流也不會潤濕CBDOS表面，而是沿表面成股流下?！敖涤辍蓖Ｖ购?，表面未見明顯的液滴粘附或形變。圖7b將亞甲基藍粉末撒落于傾斜10°放置的CBDOS模擬戶外灰塵粘附后的表面，再滴落1滴100 μL純化水。隨著水滴滑落，CBDOS表面的“灰塵”可被水滴完全帶走，從而使表面重新恢復(fù)潔凈。研究也對CBDOS的戶外應(yīng)用進行了初步探索。將CBDOS分別于戶外放置5、10、15 d后，以純化水洗凈表面，并于50 ℃烘干，測試其表面水CA值分別為108.61°、108.83°、108.40°，與戶外測試前的CBDOS表面性能基本一致。CBDOS表面優(yōu)異的自清潔功能可助其在雨水作用下去除表面粘附的污染物，恢復(fù)表面性能，使其有望應(yīng)用于建筑外墻、海洋防污等戶外場景。

圖5 污染物液滴在不銹鋼和CBDOS表面的形態(tài)

圖6 不銹鋼和CBDOS表面的自清潔功能

圖7 CBDOS表面在模擬戶外條件下的自清潔功能

3 結(jié)論

1）通過非化學(xué)計量比的pre-CBDOS表面剩余的硅氫鍵和單乙烯基封端MVT-PDMS之間的氫化硅烷化反應(yīng)，成功制得具有卓越動態(tài)雙疏性能和自清潔功能的共價鍵合型CBDOS表面。本研究方法簡便，條件溫和，對環(huán)境無污染，并且適用于惰性基底。

2）CBDOS表面顯示出極低的水和正十六烷SA值、CAH值。其中，極性的水SA值為2.20°、CAH值為1.75°，非極性的正十六烷SA值為7.33°、CAH值為7.34°，都小于8°。均勻平滑的表面形貌與單端共價鍵合的液狀MVT-PDMS所具有的高度移動性和柔韌性是CBDOS獲得低SA值、CAH值及動態(tài)雙疏性能的關(guān)鍵要素。同時，由于液狀PDMS鏈?zhǔn)枪矁r鍵合在CBDOS表面的，可有效提高表面的穩(wěn)定性。

3）CBDOS表面具有全面的動態(tài)抗?jié)櫇裥阅埽瑢O性或非極性、相溶或不相溶、水溶性或油溶性的污染物都展示出良好的自清潔功能，并可在液體沖刷下輕松去除表面粘附的粉塵，這將使其有望應(yīng)用于醫(yī)藥衛(wèi)生、食品加工、建筑外墻、海洋防污等諸多領(lǐng)域。

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Fabrication and Self-cleaning Function of Covalently-bonded Dynamically-omniphobic Surface Based on Liquid-like PDMS

(School of Pharmacy, Quanzhou Medical College, Fujian Quanzhou 362011, China)

To fabricate a stable surface with dynamic omniphobicity and self-cleaning function on inert substrates, in this paper, a facile approach was developed. The covalently-bonded dynamically-omniphobic surface (CBDOS) was prepared on inert stainless steel substrate by hydrosilylation, which was reacted between the Si-H bond in non-stoichiometry silicone rubber and monovinyl terminated polydimethylsiloxane. CBDOS was transparent, smooth, flouride-free and stable. Then, ATR-FTIR and XPS were used to characterize the chemical composition, which confirmed that liquid-like PDMS had been successfully covalently boned to CBDOS surface. AFM and FE-SEM were used to analyze the surface topography, and the results showed that CBDOS surface considerably smooth with nanoscale roughness. The AFM-derived root mean square roughness (q) of CBDOS surface was only 0.964 nm. Drop shape analyzer was used to study the anti-wettability and measure values of contact angle (CA), sliding angle (SA) and contact angle hysteresis (CAH). The water SA and CAH values were 2.20° and 1.75°, and n-hexadecane SA and CAH values were 7.33° and 7.34°, respectively. The data indicated that CBDOS revealed excellent dynamic omniphobicity and well storage stability. Therefore, CBDOS had outstanding self-cleaning function toward many kinds of common contaminants, whether they were polar or non-polar, soluble or insoluble, water-soluble or oil-soluble. It was believed that there were two key factors for CBDOS to realize excellent dynamic omniphobicity and self-cleaning function, one was the extremely homogeneous and smooth surface morphology, the other was the high mobility and flexibility of liquid-like PDMS which was only one end covalently grafted to CBDOS surface. This approach had lots of advantages such as simple operation, mild conditions and non-pollution, in addition, it could be applied to all types of substrates. Furthermore, due to the strategy of covalently bonding, the stability of dynamically omniphobic surfaces based on liquid-like PDMS had been improved distinctly.

polydimethylsiloxane; liquid-like polymer; hydrosilylation; covalent bonding; dynamic omniphobicity; self- cleaning

TB34

A

1001-3660(2022)04-0356-09

10.16490/j.cnki.issn.1001-3660.2022.04.038

2021-03-29；

2022-01-04

2021-03-29；

2022-01-04

泉州市醫(yī)療衛(wèi)生領(lǐng)域指導(dǎo)性科技計劃項目（2021N126S）

The Quanzhou Guiding Science and Technology Project in the Medical and Health Field (2021N126S)

黃穎芬（1982—），女，博士，講師，主要研究方向為功能高分子。

HUANG Ying-fen (1982—), Female, Doctor, Lecturer, Research focus: functional polymer.

黃穎芬. 基于液狀PDMS的共價鍵合型動態(tài)雙疏表面及其自清潔功能[J]. 表面技術(shù), 2022, 51(4): 356-364.

HUANG Ying-fen. Fabrication and Self-cleaning Function of Covalently-bonded Dynamically-omniphobic Surface Based on Liquid-like PDMS [J]. Surface Technology, 2022, 51(4): 356-364.

責(zé)任編輯：劉世忠