徐亞洲，何瑾馨,b，朱衛(wèi)彪，董霞,c，趙強(qiáng)強(qiáng),b

基于含氟改性籠狀倍半硅氧烷一步法制備透明超疏水涂層

徐亞洲a，何瑾馨a,b，朱衛(wèi)彪a，董霞a,c，趙強(qiáng)強(qiáng)a,b

（東華大學(xué) a.化學(xué)化工與生物工程學(xué)院 b.紡織面料技術(shù)教育部重點(diǎn)實(shí)驗(yàn)室 c.國(guó)家染整工程技術(shù)研究中心，上海 201620）

為了研究出一種在光滑鏡面基材上大面積制備透明耐用的超疏水涂層，需要克服當(dāng)前超疏水涂層存在的理化穩(wěn)定性差、光學(xué)透明度不高以及制備繁瑣、難以大面積實(shí)施等問(wèn)題。通過(guò)向聚氨酯丙烯酸酯疏水性光固化樹脂體系中引入含氟低表面能改性的籠狀倍半硅氧烷（POSS），結(jié)合噴涂法和相分離法在聚碳酸酯（PC）表面制備了一種超疏水光固化涂層。探究了低表面能改性POSS的摻雜量和乙醇添加量對(duì)構(gòu)筑超疏水涂層的影響。當(dāng)POSS-SH-DFMA7的摻雜量為樹脂含量的40%、乙醇的添加量為溶劑THF的25%時(shí)，涂層表現(xiàn)出優(yōu)異的超疏水特性，靜態(tài)水接觸角和滑動(dòng)角分別可達(dá)到156.92°和3.24°；良好的光學(xué)透明性，光線透過(guò)率為85.63%；可靠的機(jī)械穩(wěn)定性，承受6 h的水滴沖擊后依然保持超疏水特性；穩(wěn)定的耐候和耐化學(xué)性，經(jīng)歷戶外環(huán)境和不同pH值化學(xué)試劑的侵蝕后仍可保持涂層原有的潤(rùn)濕性能。在光固化樹脂體系中引入一定量的含氟單體改性POSS結(jié)合乙醇的作用可以一步法制備出透明、理化性能穩(wěn)定的超疏水涂層。

POSS；超疏水涂層；透明；耐用；噴涂；相分離；紫外光固化

超疏水表面因?yàn)樽陨愍?dú)特的潤(rùn)濕性能，已經(jīng)在越來(lái)越多的領(lǐng)域得到廣泛應(yīng)用，如防污自清潔[1-2]、減阻[3-4]、防覆冰[5-6]、油/水分離[7-8]等。最早科學(xué)家們受自然界中“荷葉效應(yīng)”[9]的啟發(fā)，于2002年首次提出了呈現(xiàn)這種大接觸角和低附著力是由于表面微納復(fù)合結(jié)構(gòu)協(xié)同作用的觀點(diǎn)，為之后超疏水表面的模型構(gòu)建提供了理論基礎(chǔ)。目前，制備超疏水表面的構(gòu)筑方法主要分為兩大類——自上而下[10]和自下而上[11]，自上而下法包括模板法[12]、等離子體刻蝕法[13]、印刷法[14]等，自下而上法包括化學(xué)沉積法[15]、相分離法[16]、溶膠-凝膠法[17]、噴涂法[18]等。雖然方法紛雜多樣，但構(gòu)造原理都是從降低表面能和提高表面粗糙度這2個(gè)角度出發(fā)。

近些年來(lái)，隨著超疏水技術(shù)在人們生產(chǎn)生活中扮演的角色愈發(fā)重要，涂層技術(shù)的研究一直在不斷革新，從對(duì)超疏水基礎(chǔ)結(jié)構(gòu)的研究發(fā)展到將功能化納米粒子低牢度化附著于表面，再到超疏水成分與整體涂層形成均一穩(wěn)定的連結(jié)體系。雖然很多研究已經(jīng)在超疏水表面的創(chuàng)新性構(gòu)造方面取得了重大進(jìn)步，但是真正能規(guī)?；a(chǎn)的產(chǎn)品卻少之又少?，F(xiàn)階段，構(gòu)筑超疏水表面能常使用的低表面能材料主要為長(zhǎng)鏈全氟硅烷[19]、含氟丙烯酸酯[20]和氟硅共聚物[21]，結(jié)合納米粒子的添加形成低表面能的粗糙化表面。但是如何提升納米粒子與聚合物的有效鍵合，以及如何改善改性納米粒子與基材表面的穩(wěn)定黏附與耐久性始終是一個(gè)難點(diǎn)。而且對(duì)于一些透明[22]、光滑的基材，如何在不影響透光率的基礎(chǔ)上使其具備良好的各項(xiàng)應(yīng)用性能，是目前透明超疏水涂層領(lǐng)域的一大難題。

為了解決以上問(wèn)題，本研究采用籠狀低聚倍半硅氧烷（POSS[23]）作為粗糙度構(gòu)建的納米材料，因?yàn)槠浔旧硖烊坏某叨葍?yōu)勢(shì)（2～5 nm）以及獨(dú)特的分子內(nèi)化結(jié)構(gòu)，8個(gè)頂點(diǎn)處的Si原子可以通過(guò)化學(xué)反應(yīng)連接各種反應(yīng)性或非反應(yīng)性基團(tuán)。因此可以通過(guò)巰基-烯點(diǎn)擊化學(xué)反應(yīng)[24]將含氟單體引入到POSS中，得到的產(chǎn)物不僅具備低表面能特性，還可以參與多層次粗糙結(jié)構(gòu)的構(gòu)建。另外，由于POSS本身具備良好的溶解性、尺寸穩(wěn)定性和熱穩(wěn)定性等優(yōu)點(diǎn)，涂層的各項(xiàng)應(yīng)用性能會(huì)隨著POSS的加入得到顯著提升。所以本研究采取將改性納米POSS與光固化樹脂[25]（成膜速度快，與基材附著力強(qiáng)）混合，采用一步噴涂法結(jié)合相分離法，在聚碳酸酯[26]表面制備出了操作簡(jiǎn)便、可大規(guī)模實(shí)施的超疏水涂層。該涂層在不影響基材本身光學(xué)透明性的同時(shí)還具備良好的機(jī)械和化學(xué)穩(wěn)定性。該研究可以為超疏水涂層的大面積生產(chǎn)以及在透明光學(xué)領(lǐng)域的大范圍應(yīng)用提供參考。

1 試驗(yàn)

1.1 八乙烯基POSS的疏水改性

1.1.1 八乙烯基POSS的巰基化

在吳城峰等[27]提出的POSS-SH8合成方法的研究基礎(chǔ)上，先對(duì)八乙烯基POSS進(jìn)行巰基化處理，得到了POSS-SH8。然后利用巰基-烯點(diǎn)擊反應(yīng)對(duì)POSS- SH8進(jìn)行氟烷基改性。

1.1.2 巰基POSS的氟烷基化

A液：將5.6 g甲基丙烯酸十二氟庚酯（DFMA）和0.06 g光引發(fā)劑I907溶于20 mL無(wú)水THF中，并且用錫箔紙將其裹好作避光處理。B液：稱量2.77 g POSS-SH8溶于20 mL無(wú)水THF中。整個(gè)反應(yīng)體系是在充滿干燥N2的氛圍下進(jìn)行。A液通過(guò)恒壓漏斗以20 mL/h的恒定速度滴入裝有B液的平底石英單口燒瓶中，待A液滴加完后，在紫外燈下繼續(xù)曝光攪拌反應(yīng)6 h。用聚四氟乙烯注射器濾膜濾去反應(yīng)后溶液中的不溶物，然后旋轉(zhuǎn)蒸餾除去部分THF溶劑。向剩余溶液內(nèi)加入一定量的無(wú)水乙醇后，使用離心機(jī)高速離心，得到白色固體物質(zhì)。接著，使用無(wú)水乙醇反復(fù)沖洗白色固體物質(zhì)5～8次。最后在50 ℃的真空干燥烘箱放置36 h，完全去除溶劑后，得到目標(biāo)產(chǎn)物POSS-SH-DFMA7。

1.2 涂層的制備

先將0.05 g疏水性樹脂與稀釋劑HDDA混合均勻后（疏水性樹脂∶HDDA=4∶1），再加入混合樹脂質(zhì)量分?jǐn)?shù)為2%的光引發(fā)劑（I907），以上體系混合均勻后將其加入到5 mL的THF中。室溫下，在轉(zhuǎn)速為800 r/min的條件下磁力攪拌2 h，形成均勻的樹脂溶液。然后將不同質(zhì)量分?jǐn)?shù)的POSS-SH-DFMA7（10%、20%、30%、40%、50%）（占樹脂添加量）和不同體積分?jǐn)?shù)的乙醇（15%、25%、35%、45%、55%）（占THF添加量）分別先后加入到溶液中，先在超聲波震蕩裝置中超聲分散1 h，然后室溫下磁力攪拌24 h。

1.3 樹脂的噴涂與固化

在噴槍口徑為1.0 mm、流速為0.25 mL/s、壓縮氣壓為0.6 MPa的設(shè)置下進(jìn)行噴涂，基材距離噴槍噴嘴25～27 cm，移動(dòng)速度為3 cm/s，自上而下進(jìn)行S型噴涂。將自然晾干的涂層試樣放入紫外光固化儀中，紫外光源是1 000 W的高壓汞燈，基材距離紫外燈源28～30 cm，在N2氛圍下固化5 min。

1.4 表征與性能測(cè)試

采用傅里葉變溫紅外光譜儀記錄FTIR光譜，分析所得樣品中主要物質(zhì)的化學(xué)組成。靜態(tài)水接觸角（WCA）使用座滴法通過(guò)在樣品涂層表面滴加5滴5 μL的液滴取其平均值。通過(guò)掃描電子顯微鏡和三維超景深顯微鏡，研究不同粗糙結(jié)構(gòu)復(fù)合涂層的表面形貌和粗糙度。采用紫外分光光度計(jì)測(cè)量涂層的透光率，測(cè)試范圍380～800 nm。

涂層機(jī)械穩(wěn)定性測(cè)試：采用自制裝置，水滴以2 滴/s的速率在高度為30 cm處勻速釋放，測(cè)定不同時(shí)間下涂層表面的靜態(tài)接觸角。

涂層耐候性：將3種超疏水涂層置于戶外露天的環(huán)境中，每隔3 d記錄1次它們的接觸角變化。

化學(xué)穩(wěn)定性測(cè)試：將3種超疏水涂層用pH值為1～14的HCl和NaOH溶液浸沒(méi)24 h，記錄各個(gè)pH值下不同涂層的接觸角。

2 結(jié)果與討論

2.1 POSS-SH8和POSS-SH-DFMA7的結(jié)構(gòu)分析

POSS-SH8合成前后主要物質(zhì)的紅外光譜圖如 圖1a所示。在八乙烯基POSS中，1 604 cm?1處為—C==C—的伸縮振動(dòng)特征峰，3 069 cm?1處為H2C==CH—上的C—H鍵的伸縮振動(dòng)特征峰，而在POSS-SH8中這2個(gè)特征峰消失了。在新產(chǎn)物中出現(xiàn)了2 548 cm?1處的—SH鍵的伸縮振動(dòng)特征峰，1 022 cm?1處以及682 cm?1處C—S鍵的特征振動(dòng)峰。這些特征峰的消失與出現(xiàn)證明了原八乙烯基POSS中的碳碳雙鍵與巰基發(fā)生了加成反應(yīng)，生成了目標(biāo)產(chǎn)物POSS- SH8。POSS-SH-DFMA7合成前后主要物質(zhì)的紅外光譜圖如圖1b所示。對(duì)比2種反應(yīng)物和1種生成產(chǎn)物的紅外光譜圖，可以發(fā)現(xiàn)，在發(fā)生巰基-烯點(diǎn)擊反應(yīng)后，生成物中碳碳雙鍵的特征吸收峰消失了，說(shuō)明含氟丙烯酸酯單體反應(yīng)完全；在2 540 cm?1處生成物相較于反應(yīng)物POSS-SH8的S—H鍵伸縮振動(dòng)吸收峰有明顯的減弱，說(shuō)明反應(yīng)物中部分巰基參與了反應(yīng)；1 182 cm?1處的碳氟鍵和1 090 cm?1處的硅氧鍵特征峰都在生成物中出現(xiàn)了。所以通過(guò)以上的分析可以確定POSS-SH-DFMA7被成功合成。

圖1 POSS巰基化前后（a）及巰基POSS氟烷基化前后主要物質(zhì)的紅外光譜圖（b）

2.2 POSS-SH-DFMA7和乙醇的添加量對(duì)涂層潤(rùn)濕性能的影響

原PC基材的接觸角為76.19°，滾動(dòng)角大于90°。純聚氨酯丙烯酸酯涂層已經(jīng)達(dá)到疏水效果，接觸角為92.78°。為了進(jìn)一步提升涂層的疏水性能，通過(guò)加入改性過(guò)的含氟鏈段改性納米POSS來(lái)降低表面能和提升表面粗糙度。根據(jù)圖2，納米POSS-SH-DFMA7的添加量為20%時(shí)，涂層展現(xiàn)出最好的疏水性，WCA為127°，滾動(dòng)角為17°。為了研究乙醇的添加量對(duì)涂層疏水性的影響，將POSS-SH-DFMA7的添加量初步確定為20%，探究不同乙醇添加量對(duì)疏水涂層接觸角和滾動(dòng)角的變化。

如圖3所示，在POSS-SH-DFMA7添加量為20%的涂層配方體系中，當(dāng)乙醇的添加量為25%時(shí)，涂層WCA的達(dá)到了139°，此時(shí)的SA最小，為11°。由于THF的揮發(fā)性大于乙醇，溶劑THF揮發(fā)后，涂層里剩下未揮發(fā)的不良溶劑乙醇，納米POSS在乙醇誘導(dǎo)聚集的作用下，慢慢凝聚成尺寸更大的顆粒。當(dāng)體系中乙醇添加量小于25%時(shí)，期間的粗糙微結(jié)構(gòu)數(shù)量雖然很多，但是由于乙醇量較少導(dǎo)致聚集程度不夠，顆粒多以納米級(jí)結(jié)構(gòu)為主，難以托舉起水滴，因此該過(guò)程中涂層的接觸角隨乙醇量的增加而變大。當(dāng)加入的乙醇量為45%時(shí)，聚集達(dá)到臨界狀態(tài)，粗糙度達(dá)到最大。進(jìn)一步提升乙醇的添加量，就會(huì)促使大顆粒形成，導(dǎo)致表面微結(jié)構(gòu)數(shù)量減少，疏水性能下降。

圖2 POSS-SH-DFMA7含量對(duì)涂層表面潤(rùn)濕性能的影響

圖3 POSS-SH-DFMA7添加量為20%時(shí)乙醇的添加量對(duì)涂層潤(rùn)濕性能的影響

由于POSS-SH-DFMA7添加量為20%時(shí)無(wú)法使涂層具備超疏水特性。于是分別探究了低表面能納米POSS添加量為30%、40%、50%的情況下乙醇的最佳添加比例。如圖4a所示，當(dāng)POSS-SH-DFMA7的添加量為30%時(shí)，乙醇添加量為35%，此時(shí)疏水效果最佳，WCA增大到151°，SA降低至8°左右，已經(jīng)達(dá)到超疏水效果。如圖4b所示，納米POSS-SH-DFMA7的添加量為40%、乙醇的添加量為25%時(shí)，構(gòu)造出了靜態(tài)水接觸角達(dá)157°、滾動(dòng)角小到3.3°的超疏水表面。如圖4c所示，低表面能納米尺寸粒子添加量為50%時(shí)，涂層疏水性的變化趨勢(shì)與POSS-SH-DFMA7添加量為40%時(shí)大體一致。乙醇添加量為25%時(shí)，涂層的疏水性能最佳，靜態(tài)水接觸角可達(dá)161°，滾動(dòng)角更是小至1.8°。

2.3 POSS-SH-DFMA7光固化涂層表面形貌分析

采用SEM掃描電子顯微鏡和三維超景深顯微鏡分別對(duì)POSS-SH-DFMA7添加量為30%、40%、50%最佳疏水效果涂層進(jìn)行表面形貌和粗糙度表征，結(jié)果如圖5所示。從圖5可以看出，隨著納米POSS-SH- DFMA7添加量的增加，涂層表面形成的微米團(tuán)簇變得越來(lái)越多，間隙越來(lái)越小。由于團(tuán)簇是微納復(fù)合結(jié)構(gòu)，這種分級(jí)結(jié)構(gòu)可以捕獲大量空氣，致使涂層表面和水滴之間可以產(chǎn)生一層“氣墊”，這層“氣墊”極大地減少了水滴與固體表面的接觸面積，因此疏水性能得到提升。粗糙度在3D超景深圖像中體現(xiàn)為凸起結(jié)構(gòu)的高度和密度。由圖5三維超景深顯微結(jié)果可知，在乙醇相分離的作用下，粗糙度隨納米POSS-SH- DFMA7添加量的增加而變得越來(lái)越大，平均粗糙度分別為1.87、4.43、5.54 μm。這與涂層SEM圖所反映出的信息一致。

圖4 POSS-SH-DFMA7添加量分別為30%、40%和50%時(shí)乙醇的添加量對(duì)涂層潤(rùn)濕性能的影響

圖5 POSS30Et35、POSS40Et25和POSS50Et25涂層試樣的表觀形貌和表觀粗糙度

2.4 涂層透光性能測(cè)試

通過(guò)紫外分光光度計(jì)測(cè)試PC空白試樣和POSS30Et35、POSS40Et25、POSS50Et25 超疏水涂層的透光率，其透光率曲線如圖6所示。從透光率曲線可以看出，在450～780 nm波段范圍內(nèi)PC空白試樣的平均透光率為89.76%，涂層POSS30Et35的平均透光率為86.12%，涂層POSS40Et25的平均透光率為83.63%，涂層POSS50Et25的平均透光率為77.37%。在乙醇的相分離作用下，3種超疏水涂層的透明性是隨著納米顆粒添加量的增加呈現(xiàn)出下降的趨勢(shì)。光的散射和折射是影響涂層光線透過(guò)率的主要因素。

圖6 空白試樣、POSS30Et35、POSS40Et25和POSS50Et25樣品的涂層透過(guò)率曲線

2.5 涂層的機(jī)械穩(wěn)定性測(cè)試

使用如圖7a所示的水滴沖擊自制設(shè)備，進(jìn)行超疏水涂層機(jī)械穩(wěn)定性能的表征。以每秒2滴的速率向涂層表面釋放液滴，每隔0.5 h記錄各涂層的接觸角變化，如圖7b所示。在經(jīng)過(guò)水滴沖擊4 h后，涂層POSS30Et35的超疏水性消失。而另外2個(gè)涂層體系中，由于納米粒子更多且分布更均勻，即使在水滴沖擊6 h后，依然維持著良好的超疏水特性。其中涂層POSS40Et25的接觸角的下降幅度最小，說(shuō)明其耐水滴沖擊性能最優(yōu)異，機(jī)械穩(wěn)定性最好。

2.6 涂層的耐候和化學(xué)穩(wěn)定性能測(cè)試

圖8a是3種超疏水涂層在戶外環(huán)境中的耐候測(cè)試結(jié)果，在相同的測(cè)試周期中，3種涂層的接觸角都呈現(xiàn)出了一定的下降趨勢(shì)，其中涂層POSS40Et25的下降幅度最小，說(shuō)明該涂層的耐候性能最穩(wěn)定。圖8b是3種超疏水涂層的化學(xué)穩(wěn)定性測(cè)試結(jié)果。3種超疏水涂層對(duì)不同pH值范圍的溶液展現(xiàn)出不同的化學(xué)穩(wěn)定性，根據(jù)圖示曲線的起伏程度，可發(fā)現(xiàn)涂層POSS40Et25對(duì)不同溶劑的適應(yīng)力更強(qiáng)，化學(xué)穩(wěn)定性最佳。相較于涂層POSS30Et35，涂層POSS40Et25具有更致密的粗糙結(jié)構(gòu)和更高的表面起伏，不管是雨水還是酸堿溶液，與空氣的接觸面積大，不易與涂層內(nèi)部直接接觸，受侵蝕的程度更小，疏水性能的保持能力更好。而涂層POSS40Et25比涂層POSS50Et25的耐候和化學(xué)穩(wěn)定性更優(yōu)，主要?dú)w因于前者涂層體系中納米POSS的添加量適度，相分離后的粗糙結(jié)構(gòu)與光固化樹脂之間存在的有效連接趨向于體系的飽和值。另外，在本試驗(yàn)條件下制備的涂層對(duì)涉及酸雨的實(shí)際應(yīng)用效果更好。

圖7 耐水滴沖擊測(cè)試裝置圖（a）及3種涂層表面在6 h水滴的持續(xù)沖擊下接觸角值的變化（b）

圖8 3種超疏水涂層在戶外環(huán)境中的耐氣候測(cè)試（a）及不同pH值下的化學(xué)穩(wěn)定性測(cè)試（b）

3 結(jié)論

本文選取一步噴涂相分離法結(jié)合紫外光固化技術(shù)作為制備超疏水涂層的方法。采用聚氨酯疏水改性丙烯酸酯作為樹脂基體，HDDA為預(yù)聚體稀釋劑，低表面能的POSS-SH-DFMA7為納米填料，THF為溶劑，乙醇為不良溶劑。綜合探究分析后，得出以下結(jié)論：當(dāng)納米POSS-SH-DFMA7添加量為樹脂的40%，不良溶劑乙醇添加量為THF的25%時(shí)，涂層的超疏水效果優(yōu)異，WCA值可達(dá)到156.92°，滾動(dòng)角小至 3.24°，而且涂層的各項(xiàng)應(yīng)用性能更貼合使用需求，比如高達(dá)85.63%的涂層透明度、經(jīng)受長(zhǎng)時(shí)間水滴沖擊測(cè)試后可靠的涂層黏結(jié)力、多元環(huán)境長(zhǎng)期作用后優(yōu)異的涂層耐候性能以及不同pH值化學(xué)試劑侵蝕后穩(wěn)定的涂層耐化學(xué)性能。

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Transparent Superhydrophobic Coating Prepared by One-step Method Based on Fluorinated Cage-like Sesimiloxane

a,a,b,a,a,c,a,b

(a. School of Chemistry, Chemical Engineering and Biotechnology, b. Key Lab of Textile Science & Technology, Ministry of Education, c. National Engineering Research Center for Dyeing and Finishing of Textiles, Donghua University, Shanghai 201620, China)

The coating film-forming method has good application prospects in the preparation of transparent superhydro-phobic coatings due to its simple process, good repeatability and low equipment requirements. However, the nanofillers in the existing coating film-forming methods generally have defects such as easy aggregation and poor durability. POSS is an organic- inorganic hybrid with a special cage-like structure. Compared with ordinary nanofillers, POSS has the characteristics of monodi-spersity and flexible functional modification. At present, most of the researches on POSS in the field of superhydrophobic coatings are based on rough substrate surfaces, but few researches have been done in the field of mirror-transparent optics. Therefore, the purpose of this study is to select POSS as a nanofiller and use a one-step coating film-forming method to construct a large-area transparent and durable superhydrophobic coating on a mirror substrate.

In this study, an intermediate POSS-SH8was synthesized from octavinyl POSS and ethanedithiol based on a two-step thiol-ene click chemistry reaction. Then, POSS-SH8and dodecafluoroheptyl methacrylate monomer were used as reactants to obtain low surface energy modified product POSS-SH-DFMA7through photoreaction. The effects of the doping mass fraction of F-POSS and the volume fraction of ethanol addition on the construction of superhydrophobic coatings were explored. The preparation of spraying prefabricated liquid was as follows: F-POSS with different mass fractions was blended in resin prepolymer. Resin prepolymer was composed of a mixture of hydrophobic photocurable resin (Changxing 6145-100) and diluent HDDA at 4∶1. After the prepolymer was evenly mixed, the dilution solvent THF was added to the system at a dilution ratio of 1∶20. It was dispersed uniformly in a stirrer and an ultrasonic shaker successively. In order to obtain the rough micro-nano composite structure on the smooth substrate surface, the method of spraying combined with non-solvent induced phase separation was adopted in this study. Different volume fractions of non-solvent ethanol were added to the above system to obtain a series of spraying prefabricated liquids. Next, the prefabricated solution was transferred to the surface of the smooth substrate by spraying and the coating was air-dried at room temperature. Finally, the air-dried coatings were cured in a UV curing apparatus under N2atmosphere for 5 minutes. The chemical composition of the main substances in the obtained samples was analyzed by infrared spectrum curve. The static water contact angle and dynamic rolling angle of the coatings were recorded by contact angle analysis and self-made rolling angle measuring instrument to characterize the hydrophobicity of the coatings. The surface topography and roughness of the composite coatings with different rough structures were investigated by scanning electron microscopy and three-dimensional ultra-depth-of-field microscopy. The transmittance of the coatings was measured by a UV spectrophotometer to characterize the transmittance of the coating. A self-made device was used to set water droplets to be released at a uniform rate of 2 drops per second at a height of 30 cm. The hydrophobic property retention curve of the coatings at different times were obtained to characterize the mechanical stability of the coating. The three superhydrophobic coatings were placed in an outdoor open-air environment, and their contact angle changes were recorded every 3 days to evaluate their weatherability. In addition, the above three coatings were soaked in HCl and NaOH solutions with pH values ??of 1 to 14 for 24 hours. And the contact angle curves of each coating at different pH values ??were recorded to compare their resistance to reagents.

The research results show that the coating exhibits excellent superhydrophobic properties when the doping mass fraction of POSS-SH-DFMA7is 40% of the resin content and the addition volume fraction of ethanol is 25%. The static water contact angle and sliding angle can reach 156.92° and 3.24°, respectively. In addition, the superhydrophobic coating prepared under the optimal process conditions also has good optical transparency and its light transmittance is 85.63%. The coating still maintains superhydrophobic property after being impacted by water droplets for 6 hours, indicating its mechanical stability. Not only that, the original wetting property of the coating can still be maintained after experiencing various outdoor environments and the erosion of chemical agents with different pH values. Therefore, the introduction of a certain amount of fluorine-containing monomer to modify the POSS combined with the phase separation of ethanol into the photocurable resin system can prepare a large-area transparent and superhydrophobic coating with stable physical and chemical properties in one step.

POSS; superhydrophobic coating; transparent; durable; spraying; phase separation; UV curing

tg174；tb34

A

1001-3660(2022)10-0336-08

10.16490/j.cnki.issn.1001-3660.2022.10.036

2021–09–22；

2022–01–22

2021-09-22；

2022-01-22

國(guó)家重點(diǎn)研發(fā)計(jì)劃項(xiàng)目（2017YFB0309100）

Supported by the National Key Technologies R & D Program of China (2017YFB0309100)

徐亞洲（1997—），男，碩士研究生，主要研究方向?yàn)楣δ苄跃酆衔锊牧稀?/p>

XU Ya-zhou (1997-), Male, Postgraduate, Research focus: functional polymer material.

何瑾馨（1959—），男，博士，教授，主要研究方向?yàn)榧徔椈瘜W(xué)與染整工程。

HE Jin-xin (1959-), Male, Doctor, Professor, Research focus: textile chemistry and dyeing & finishing engineering.

徐亞洲，何瑾馨，朱衛(wèi)彪，等. 基于含氟改性籠狀倍半硅氧烷一步法制備透明超疏水涂層[J]. 表面技術(shù), 2022, 51(10): 336-343.

XU Ya-zhou, HE Jin-xin, ZHU Wei-biao, et al. Transparent Superhydrophobic Coating Prepared by One-step Method Based on Fluorinated Cage-like Sesimiloxane[J]. Surface Technology, 2022, 51(10): 336-343.

責(zé)任編輯：萬(wàn)長(zhǎng)清