Wettability Control between Oleophobic/Superhydrophilic and Superoleophilic/Superhydrophobic Characteristics on the Modified Surface Treated with Fluoroalkyl End-Capped Oligomers/Micro-Sized Polystyrene Particle Composites

Fluoroalkyl end-capped vinyltrimethoxysilane-N,N-dimethylacrylamide cooligomer [RF-(CH2-CHSi(OMe)3)x-(CH2-CHC(=O)NMe2)y-RF;RF = CF(CF3)OC3F7: RF-(VM)x-(DMAA)y-RF] was synthesized by reaction of fluoroalkanoyl peroxide [RF-C(=O)O-O(O=)C-RF] with vinyltrimethoxysilane (VM) and N,N-dimethylacrylamide (DMAA). The modified glass surface treated with the cooligomeric nanoparticles [RF-(VM-SiO3/2)x-(DMAA)y-RF] prepared under the sol-gel reaction of the cooligomer under alkaline conditions was found to exhibit an oleophobic/superhydrophilic property, although the corresponding fluorinated homooligomeric nanoparticles [RF-(VM-SiO3/2)n-RF] afforded an oleophobic/hydrophobic property on the modified surface under similar conditions. RF-(VM-SiO3/2)n-RF/RF-(VM-SiO3/2)x-(DMAA)y-RF/PSt (micro-sized polystyrene particles) composites, which were prepared by the sol-gel reactions of the corresponding homooligomer and cooligomer in the presence of PSt particle under alkaline conditions, provided an oleophobic/superhydrophilic property on the modified surface. However, it was demonstrated that the surface wettability on the modified surface treated with the RF-(VM-SiO3/2)n-RF/RF-(VM-SiO3/2)x-(DMAA)y-RF/PSt composites changes dramatically from oleophobic/superhydrophilic to superoleophilic/superhydrophilic and superoleophilic/superhydrophobic characteristics, increasing with greater feed ratios (mg/mg) of the RF-(VM)n-RF homooligomer in homooligomer/cooligomer from 0 to 100 in the preparation of the composites. Such controlled surfac

Superhydrophobic and mechanically robust polysiloxane composite coatings containing modified silica nanoparticles and PS-grafted halloysite nanotubes

Excellent mechanical properties are the prerequisite for the application of superhydrophobic polymer coatings.However,significantly improving the mechanical properties without affecting other properties such as hydrophobicity is a huge challenge.In this study,a superhydrophobic coating with excellent mechanical properties was prepared by spraying a mixture of polysiloxane resins based on three siloxane monomers,hexadecyltrimethoxysilane(HDTMS) modified nano-SiO_(2)particles(SiO_(2)-HDTMS) and polystyrene-grafted halloysite nanotubes(HNTs-PS).SiO_(2)-HDTMS dispersed homogeneously in polysiloxane coatings and the water contact angle of corresponding coating exceeding 150°,achieving superhydrophobicity.The SiO_(2)-HDTMS/HNTs-PS/polysiloxane composite coatings showed excellent abrasion resistance with the water coating contact angle remaining above 150°after 90 abrasion cycles,indicating that HNTs-PS can significantly improve the mechanical properties of the coating without affecting the hydrophobic properties of the coating.The achieved coating also exhibited excellent antifouling and acid and alkali corrosion resistance.This work provides a convenient and ecologically friendly method to prepare superhydrophobic polysiloxane composite coating with excellent mechanical properties,which is promising in the application of anti-fouling,anti-corrosion,and oil-water separation etc.

Effect of modified MgAl-LDH coating on corrosion resistance and friction properties of aluminum alloy

The in-situ growing approach was utilized in this article to construct the magnesium–aluminum layered double hydroxide(MgAl-LDH)film on the surface of a 1060 aluminum anodized film.To improve the corrosion resistance and friction qualities of aluminum alloy,the MgAl-LDH coating was treated using stearic acid(SA)and thiourea(TU).The aluminum substrate and anodized aluminum film layer corroded to varying degrees after 24 h of immersion in 3.5%(mass)NaCl solution,while the modified hydrotalcite film layer continued to exhibit the same microscopic morphology even after being immersed for 7 d.The results show that the synergistic action of thiourea and stearic acid can effectively improve the corrosion resistance of the MgAl-LDH substrate.The tribological testing reveals that the hydrotalcite film layer and the modified film layer lowered the friction coefficient of the anodized aluminum surface substantially.The results of the simulations and experiments demonstrate that SA forms the dense LDH-TU interlayer film layer by exchanging NO_(3)^(-)ions between TU layers on the one hand and the LDH-SA film layer by adsorption on the surface of LDH on the other.Together,these two processes create LDH-TUSA,which can significantly increase the substrate’s corrosion resistance.This synergistically modified superhydrophobic and retardant hydrotalcite film layer offers a novel approach to the investigation of wear reduction and corrosion protection on the surface of aluminum and its alloys.

纳米SiO_(2)复合粒子/有机硅低聚物透明超疏水复合涂层的制备及其性能

将Stöber法制备的胶体SiO_(2)粒子溶液与粉体SiO_(2)粒子进行物理共混得到SiO_(2)复合粒子溶液,以三乙氧基甲基硅烷(MTES)与正硅酸乙酯(TEOS)为前驱体制备的酸性有机硅低聚物为黏结剂,使用3-氨丙基三甲氧基硅(KH540)与全氟癸基三甲基氧硅(PFDT)对其进行改性,通过喷涂法在玻璃基底上制备出SiO_(2)复合粒子/酸性有机硅低聚物复合透明超疏水涂层。考察了SiO_(2)复合粒子、酸性有机硅低聚物、KH540及PFDT对复合涂层的影响。结果表明,当SiO_(2)复合粒子溶液由粒径为110 nm的胶体SiO_(2)粒子溶液与粒径为50 nm的粉体SiO_(2)粒子(其用量为胶体SiO_(2)粒子溶液质量的1%)组成、SiO_(2)复合粒子溶液与酸性有机硅稀释液质量比为4∶1、KH540与PFDT的添加量(以混合液总质量计,下同)均为1%时,制备的复合涂层在可见光波长范围内透光率可达88%,静态接触角达155°,在800目砂纸上磨损60 cm后仍能保持超疏水性能,具有良好的自清洁性。

超疏水表面在抗/促凝血领域的研究进展

近年来,随着超疏水材料在冷凝传热、油水分离、除冰防雾、表面防腐、管道减阻等方面应用的研究逐步趋于成熟,其在生物医疗领域的应用前景也备受学者关注,由于医疗设备与血液接触时产生的凝血血栓及大量出血引发的失血性休克问题会对患者生命安全造成极大威胁。为了能够有效解决血栓出现及大量失血问题,国内外诸多学者展开了大量研究,超疏水材料由于其特殊的表面润湿性及较低的表面自由能可显著降低材料表面的血小板粘附量,其与亲水材料的组合可在止血的前提下减少出血量并降低伤口二次撕裂出血的可能,同时,研究表明超疏水材料还具有良好的抗菌性,故针对超疏水材料的研究成为了该领域的热点与方向。基于此,首先介绍了超疏水材料基本理论,主要包括Young润湿模型、Wenzel润湿模型以及Cassie-Baxter润湿模型,其次详细阐述了其在抗/促凝血过程中的作用机理,然后以部分研究为代表着重讨论了目前超疏水材料在血液接触应用领域的研究现状,指明超疏水材料在该领域的应用中主要存在的问题,最后对其未来的发展前景进行了展望。

有机-无机超疏水性涂层腐蚀性能研究

应用电极测试对简单的电化学改性法制备出的具有多层次微纳米花菜状团簇超疏水性的NiSA2-Ni(OH)2涂层进行腐蚀行为研究。并利用扫描电镜(SEM)、X-射线衍射(XRD)、润湿性测试对涂层腐蚀前与腐蚀后的微观结构及性能进行研究。具有超疏水性的NiSA2-Ni(OH)2涂层耐腐蚀比铝合金的有所提高,超疏水涂层的极化电阻Rp值提高了,腐蚀点数量减少,深度变浅,腐蚀前后的静态接触角减小程度变小。

Bio-inspired superhydrophobic magnesium alloy surfaces with active anti-corrosion and self-healing properties

Bio-inspired superhydrophobic magnesium(Mg)alloy surfaces are of increasing interest in corrosion protection due to superior barrier and shielding effects.However,superhydrophobic(SHB)anti-corrosion surfaces are susceptible to damage,which limit their extensive applications.To this end,a micro/nano structure-functional molecule SHB composite coating with self-healing and active anti-corrosion dual-function properties was designed on Mg alloys substrate.The dual-function SHB composite anti-corrosion coating based on lauric acid(La)intercalated and modified hydrotalcite(La-LDH)consisted of three-layer structure,namely La-LDH powder/polydimethylsiloxane(PDMS)/La-LDH film.The anti-corrosion performance of as-prepared coatings was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS).The results indicate that the SHB coating shows excellent active corrosion resistance.Moreover,we also examined the self-healing and anti-corrosion properties of SHB coating upon physical damage and explained the healing mechanism.After heat treatment,the damaged SHB coating regain its surface microstructure and corrosion protection property.This work expands new insights for the wide application of Mg alloys and the research in the field of metal protection.

激光-热处理复合工艺制备油水分离表面及性能研究

目的研发一种高效、低成本的激光-热处理复合工艺,制备具有油水分离性能的泡沫铜表面,为石油污染的净化提供一种有效的参考方法。方法首先利用纳秒激光在泡沫铜表面上诱导出多级微纳米结构,然后将泡沫铜放入低温烘箱中加热处理,通过调控激光参数和热处理相互作用制备出了超疏水超亲油泡沫铜表面,并使用扫描电子显微镜、光电子能谱仪和接触角测量仪,对激光加工前后泡沫铜表面的微纳结构、表面化学元素组成和油水在表面的润湿性进行了表征。结果泡沫铜表面经纳秒激光加工后诱导生成的多级微纳结构受到包括激光扫描速率、激光加工功率和扫描间距等激光加工参数的显著影响。同时,配合低温热处理工艺,激光制备泡沫铜表面的化学成分快速转变,表面能显著降低,使得泡沫铜表面获得了超疏水超亲油的润湿特性。本工作制备的泡沫铜表面在空气中的最大水接触角为158.5°,油接触角为0°。并利用油水分离试验装置验证了激光-热处理复合工艺制备的超疏水超亲油泡沫铜表面可以使油和水选择性通过,分离效率超过90%。结论激光-热处理复合工艺制备的具有多级微纳结构的泡沫铜表面具备优异的超疏水超亲油特性,展现出了良好的油水分离性能,有望实现海洋生态中石油污染的净化。

具有可拉伸性的石墨烯半导体超疏水涂层

超疏水性涂层是理想的防冰材料,超疏水性材料能够推迟冰晶的形成或降低冰黏附强度,但现有涂层存在机械性能差、性能参数自然衰老快等问题。通过将改性石墨烯部分嵌入弹性体的方法制备新型涂层,对涂层进行结冰—除冰性能测试比对,并对涂层的表面结构及化学成分进行分析。结果表明:新型涂层具有一定的电热除冰能力,机械性能测试中应变、耐磨、抗老化等方面均表现出优异的性能;引入涂层的石墨烯是使涂层具备一定主动除冰能力的关键,该涂层特有的主、被动双重除冰属性是区别于传统的被动涂层特有属性,不仅为双属性防冰涂层的研发奠定了基础也开辟了防冰涂层新的发展方向。

剥离蒙脱石/纤维素基超疏水气凝胶的构建及高效油水分离的应用

为了解决纤维素气凝胶存在的制备成本高、力学性能差、油水分离效率低等问题,将价廉易得且具有大比表面积的剥离蒙脱石(MMTex)引入到羧甲基纤维素钠(CMC)与羧基化纳米纤维素(CNF-C)的交联网络结构中,通过简单的冷冻干燥、常温浸渍法制备了超疏水的剥离蒙脱石/纤维素基气凝胶(MMTex/CMC/CNF-C)。结果表明,剥离蒙脱石的添加,进一步调控了纤维素气凝胶的孔结构,构建了致密、连续、稳定的三维蜂窝网络结构,孔隙率高达97.60%,从而协同提升了纤维素气凝胶的力学性能和吸附性能。此外,MMTex/CMC/CNF-C还表现出优越的回弹性(在60%应变下迅速恢复形变)、良好的耐酸碱盐特性和超轻且超疏水性(接触角为150.4°),保证了气凝胶在恶劣环境下的高效油水分离性能以及可循环使用性。对正己烷、环己烷、二氯甲烷、花生油和废弃机油等不同油品的吸附量达到24.6~53.8g/g,且5次循环使用后吸附量仍能维持在原始吸附量的85%,吸收的油可以被简便回收。其研究为构建具有高成本效益且高效的油水分离材料提供了参考。

超疏水-超亲油海绵的制备及其在水污染治理中的应用研究

为有效处理含油废水,满足环保要求,采用一锅水热法制备超疏水-超亲油PVA海绵材料(STt@PVA),其可瞬时吸收氯仿、正十六烷及汽油等黏度较低的有机溶剂,高黏度食用油的吸附时长约20 s;对正十六烷、汽油及氯仿的分离效率,依次是98%、93%、86%。且经过5次循环后,吸附正十六烷、氯仿-水混合物,分离效率均在83%以上,表明STt@PVA具有很好的油水分离性能和回收性。

纳米二氧化硅改性不锈钢网用于油水分离

以正硅酸乙酯为原料,采用溶胶-凝胶法制备了硅溶胶,将硅溶胶与预沉积聚多巴胺(PDA)的不锈钢网(SSM)反应,采用分步沉积和原位生长法制备了超亲水-水下超疏油不锈钢网(SSM-PDA-SiO_(2))。采用FTIR、XRD、TG、SEM和接触角测量仪对其进行了测试。探究了硅溶胶反应时间对SSM-PDA-SiO_(2)亲水-疏油性能的影响,通过自重力驱动测试了其油水分离性能,考察了其循环分离性和力学稳定性。结果表明,PDA作为“桥梁”将纳米SiO_(2)沉积到SSM表面上,硅溶胶与SSM反应8 h制备的SSM-PDA-SiO_(2)-8具有最佳的亲水-疏油性能,水滴能在其表面60 ms内完全铺展,其对二氯甲烷等5种有机溶剂的水下油接触角在156.4°~160.9°之间,对二氯甲烷的滚动角为4.0°,表现出超亲水-水下超疏油特性。首次分离正庚烷/水的油水混合物水通量为40165 L/(m^(2)·h),分离效率99.3%,在50次分离循环时水通量为17728 L/(m^(2)·h),分离效率仍>98%。经过35次砂纸摩擦循环后,SSM-PDA-SiO_(2)-8保持了98%以上的分离效率。PDA的羟基、氨基等亲水基团提高了SSM-PDA-SiO_(2)的超亲水-水下超疏油特性,纳米SiO_(2)增加了其表面粗糙度。

Superhydrophobic and superlipophilic biochar produced from microalga torrefaction and modification for upgrading fuel properties

Torrefaction operation is an essential pathway for solid biofuel upgrading,and good hydrophobicity of torrefied biochar is conducive to its storage.Herein,a two-stage treatment of torrefaction followed by modification by hexadecyltrimethoxysilane was adopted to improve the moisture resistance performance of biochar.This two-stage treatment process led to a longer torrefied microalgal biochar preservation time(60-200%improved)and great superhydrophobicity and superlipophilicity.Therefore,the modified microalgal biochar could significantly adsorb leaking oil for environmental remediation and further improve the calorific value of the biochar.The obtained results indicated that the oil adsorption capacity of modified microalgal biochar was correlated to torrefaction temperature and oil species.Specifically,the oil adsorption capacity was enhanced up to 70-80%from the modification process when comparing to raw microalga.Increasing the torrefaction temperature enhanced the adsorption quantity of the modified microalgal biochar.By adsorbing the oil,the calorific value of oilchar,namely,biochar with adsorbed oil,could be higher than 40 MJ kg^(−1).Furthermore,the pyrolysis and combustion characteristics suggested that biochar stability gradually rose as the torrefaction temperature increased.By comprehensively analyzing and comparing the fuel performance of the modified microalgal biochar with previous literature,the obtained modified microalgal biochar possessed better fuel properties and environmental sustainability.

超疏水路面抗冰涂层的制备及耐紫外老化性能研究

冬季道路积雪结冰如未及时清除会对行车安全造成严重威胁。基于表面润湿理论,采用在低表面能聚氨酯表面构建纳米级粗糙结构的方法制备超疏水涂层,通过接触角、滚动角实验、沥青混合料表面冰层破碎试验评价涂层的疏水、疏冰性。并考虑路面受紫外线强烈辐射影响,从表面能角度,分析紫外线辐射对超疏水涂层表面结构特性的影响。结果表明,制备的超疏水涂层与水滴的接触角高达161.176°,滚动角低至6.6°。超疏水沥青混合料表面冰层破碎所需的挤压力,比普通沥青混合料小。经过模拟室外紫外线辐射24个月后,超疏水涂层依然具有很好的疏水、疏冰特性。

Fabrication of Bioinspired Structured Superhydrophobic and Superoleophilic Copper Mesh for Efficient Oil-water Separation

Oily water treatment has attracted the attention of many researchers. The development of effective and cheap oil/water separation materials is urgent for treating this problem. Herein, inspired by superhydrophobic typical plant leaves such as lotus, red rose and marigold, superhydrophobic and superoleophilic copper mesh was fabricated by etching and then surface modi- fication with 1-dodecanethiol （HS（CH2）IlCH3）. A rough silver layer is formed on the mesh surface after immersion. The ob- tained mesh surface exhibits superhydrophobicity and superoleophilicity and the static water contact angle was 153~ ＋ 3~. In addition, the as-prepared copper mesh shows self-cleaning character with water and chemical stability. The as-prepared copper foam can easily remove the organic solvents either on water or underwater. We demonstrate that by using the as-prepared mesh, oils can be absorbed and separated, and that high separation efficiencies of larger than 92% are retained for various oils. Thus, such superhydrophobic and superoleophilic copper mesh is a very promising material for the application ofoil spill cleanup and industrial oily wastewater treatment.

超疏水抗皱棉织物的制备及性能分析

为了改善棉纤维易污染和易起皱问题,采用NaOH/尿素体系构筑稳健的微纳结构纤维表面,十六烷基三甲氧基硅烷(HDTMS)降低纤维表面能,丁烷四羧酸(BTCA)提高纤维耐久性和抗皱性能。利用傅里叶红外光谱、扫描电子显微镜、X射线光电子能谱和静态接触角测量仪等技术对改性后的棉织物进行表征,并对其功能性进行评价。结果显示:NaOH质量分数10%、HDTMS质量分数4%、BTCA质量分数4%时,处理后的棉织物显示出良好的超疏水性、抗皱性、防污性和自清洁性;且分别经受30次洗涤和3500次摩擦后,水接触角依然超过150°,显示了良好的超疏水耐久性。

环保型超疏水棉织物制备及油水分离应用研究

探讨聚二甲基硅氧烷(PDMS)与纳米SiO_(2)联合整理棉织物的可行性及应用效果。制备SiO_(2)/PDMS涂层溶液,将棉织物浸入其中制备SiO_(2)/PDMS@棉织物,观察不同质量分数SiO_(2)整理所得织物的微观形貌,测试织物的耐酸碱性、耐摩擦性、自清洁性和油水分离性。试验表明:PDMS与纳米SiO_(2)联合整理棉织物的水接触角能达到165.3°±3.7°;SiO_(2)的理想质量分数为5%;整理所得超疏水棉织物具有很好的化学稳定性和机械稳定性,在极端条件下对水能展现出稳定的超疏水能力,对油水混合物的分离效率保持在99.0%以上,且自清洁性能良好。认为:SiO_(2)/PDMS涂层赋予了棉织物优异的超疏水性。

活性炭负载TiO_(2)超疏水棉织物的性能研究

为研究多孔复合材料协同硅烷偶联剂改性棉织物的性能,采用溶液-溶胶法制备了活性炭负载TiO_(2)复合凝胶。通过简单的一步浸渍法将复合粒子和无氟防水剂十六烷基三甲氧基硅烷整理到棉织物表面,测试了棉织物整理前后的表面微观形貌、水接触角、表面元素组成、红外光谱、自清洁性、防污性和透气性。结果表明:改性后的棉织物表面变得粗糙,水接触角达到157°;其表面的碳、硅元素含量大幅度提升,氧元素含量减少较多,同时出现了新的元素钛;红外光谱中出现疏水性基团的强振动峰,其在水洗循环5次后水接触角仍能保持在140°。认为:改性后的棉织物达到了超疏水效果,同时具有优异的防污性和自清洁性。

乙烯醋酸乙烯酯/二氧化硅超疏水辐射降温薄膜的制备及性能

辐射降温材料通过在太阳光波段(0.3~2.5μm)反射太阳光并通过大气透明窗口波段(8~13μm)将热量辐射到寒冷的外太空以实现表面的自发降温,这是一种可持续发展的制冷方式。然而,材料在户外长期使用过程中会受到雨水冲刷或灰尘沾污而使降温效果受到严重影响。文中通过溶剂交换法制备了具有多孔结构的乙烯醋酸乙烯酯/疏水二氧化硅(EVA/SiO_(2))复合超疏水辐射降温薄膜。复合薄膜表面的水接触角为160.4°,滚动角为2.6°;在太阳光波段的平均反射率可达96%,大气透明窗口波段的平均发射率为94%。在炎热强日光照射下的空气流通环境中,该薄膜可实现比周围环境平均温度低7℃;在无空气对流和传导的理想条件下可达到12℃的平均降温。薄膜的超疏水自清洁特性可使其表面避免被外界污染从而保持稳定的光学性能和降温效果。该材料适用于户外需要降温的领域,应用前景广阔。

镍基分支化ZnOHF表面的制备及油水分离性能

目的解决目前油水分离材料大多存在的制备工艺复杂、设备昂贵、分离效率低、重复使用性差等问题。方法采用水热法在镍网表面生长分支化羟基氟化锌(Zn OHF)粗糙结构,随后在表面沉积十八烷基三甲氧基硅烷(ODS)分子,得到超疏水/超亲油镍网。利用扫描电子显微镜(SEM)、X射线衍射仪(XRD)和傅里叶变换红外光谱仪(FT-IR)对其表面的微观形貌、组织和表面成分进行表征,利用接触角测量仪表征其静态和动态润湿性能。结果镍网表面生长的分支化ZnOHF粗糙结构,与低表面能的ODS单分子层协同作用,使该表面对水的接触角高达158°,对油的接触角则为0°,且连续滴加油品时,油会在表面迅速铺展、渗透,并向下滴落。将不同品类的油与水混合,模拟不同情况下的油水分离效果,其分离效率均在95%以上;经过50次重复的油水分离测试后,其油水分离效率仍能保持91%,表现出良好的重复使用性能。结论实验制备的超疏水/超亲油镍网具有制备方法简单、成本低廉、高效耐用等优点,为含油废水的处理提供了新方法。