Faculty of Chemistry, Nicolaus Copernicus University in Toruń , 7 Gagarina Street, 87-100 Toruń, Poland.
ACS Appl Mater Interfaces. 2016 Mar 23;8(11):7509-21. doi: 10.1021/acsami.5b11975. Epub 2016 Mar 9.
The functionalization of ceramic materials, metal oxide powders (TiO2 and ZrO2), and ceramic membranes (5 kD TiO2 and 300 kD TiO2) was performed and thoroughly discussed. The objective of the functionalization was to change the natively hydrophilic character to the hydrophobic. The hydrophilic character of the ceramics generates limitations in wider application of such materials. Material functionalization was performed using perfluoroalkylsilanes and trifunctional(octyl)silanes possessing three different reactive functional groups: -Cl, -OMe, and -OEt. The characterization of functionalized metal oxide powders and ceramic membranes was assessed by a combination of various analytical methods and techniques: NMR, TGA, HR-TEM, FT-IR, SEM-EDX, AFM, and contact goniometry. The impact of molecular structure of grafting agents (type of reactive group), time of functionalization process (5-15 min), and type of membrane morphology on the material, physicochemical, and tribological properties was studied. Effectiveness of hydrophobization was confirmed by HR-TEM technique. The thickness of the attached hydrophobic nanolayer on the surface of ceramics was around 2.2 nm. It was found that the stable hydrophobic surfaces were obtained by functionalization with both fluorinated and nonfluorinated modifiers. The materials modified with perfluoroalkylsilanes (FC6OEt3) and trichloro(octyl)silanes (C6Cl3) during 15 min hydrophobization possess comparable properties: contact angle (CA) equal to 130° and 133°; roughness RMS of 10.2 and 12 nm; adhesive force of 4.1 and 5.7 nN; and Young modulus of 135 and 130 GPa, respectively. The relation between hydrophobicity level and ceramic membrane roughness was discussed applying the Kao diagram concept. (29)Si NMR results show that type of modifier has an important influence on grafting efficiency and on the mode of the grafting molecules attachment. In case of grafting with n-octyltrichlorosilane (C6OCl3) and n-octyltrimethoxysilane (C6OMe3), an increase of lateral polymerization across the octylsilane layer was observed.
陶瓷材料、金属氧化物粉末（TiO2 和 ZrO2）和陶瓷膜（5 kD TiO2 和 300 kD TiO2）的功能化得到了很好的研究。功能化的目的是将原本亲水的特性转变为疏水。陶瓷的亲水性在更广泛的材料应用中存在局限性。使用全氟烷基硅烷和三官能（辛基）硅烷对材料进行功能化，这些硅烷具有三个不同的反应性官能团：-Cl、-OMe 和-OEt。通过各种分析方法和技术对功能化金属氧化物粉末和陶瓷膜进行了表征，这些方法和技术包括：NMR、TGA、HR-TEM、FT-IR、SEM-EDX、AFM 和接触角测量。研究了接枝剂（反应性基团类型）的分子结构、功能化过程的时间（5-15 分钟）以及膜形态对材料物理化学和摩擦学性能的影响。通过高分辨率透射电子显微镜（HR-TEM）技术证实了疏水性。陶瓷表面附着的疏水纳米层的厚度约为 2.2nm。结果表明，通过使用全氟和非全氟改性剂进行功能化，可以获得稳定的疏水表面。用全氟辛基乙基硅烷（FC6OEt3）和三氯辛基硅烷（C6Cl3）进行 15 分钟的疏水处理后，材料的接触角（CA）分别为 130°和 133°，粗糙度 RMS 分别为 10.2nm 和 12nm，附着力分别为 4.1nN 和 5.7nN，杨氏模量分别为 135GPa 和 130GPa。利用 Kao 图的概念讨论了疏水性水平与陶瓷膜粗糙度之间的关系。29Si NMR 结果表明，改性剂的类型对接枝效率和接枝分子的连接方式有重要影响。在使用正辛基三氯硅烷（C6OCl3）和正辛基三甲氧基硅烷（C6OMe3）接枝的情况下，观察到辛基硅烷层的横向聚合增加。
