Preparation of superhydrophobic

The problems of supramolecular organization and distribution of bonded molecules are of great importance not only for the materials with a low surface coverage. These are also important for the preparation of the most dense bonded layers with the maximum shielding of the surface. Indeed, the complete modification of silica with alkylsilanes and preparation of superhydrophobic surfaces [44,45] are only possible under the conditions of island-like coverage of the surface with a. modifier. 

FIG U RE 8.6 A schematic diagram illustrating the preparation of superhydrophobic surfaces via layer-by-layer (LbL) coating of Ti02 nanoparticles and polyfaeryhc acid) (PAA) and fluo-roalkylsilane (FAS) surface modification. (Reprinted from Ogawa, T., et al., Nanotechnology 18, 165607, 2007. With permission.)... 

Scheme 1. Preparation of superhydrophobic PE films via a catalytic route.

It has been demonstrated that the preparation of superhydrophobic polymer surfaces is possible by simple plasma surface modification, either in one or two-step processes. The O2 plasma induces a variable roughness while CF4 plasma increases the roughness and creates an apolar layer. By the two-step treatment, several plasma parameters were found which allowed the preparation of superhydrophobic surfaces with controlled roughness and chemical structure. It has been shown that a superhydrophobic surface can be obtained even with a low roughness, around 20 nm. 

Li, X M, Reinhoudt, D, Crego-Calama, M (2009) What do we need for a superhydrophobic surface A review on the recent progress in the preparation of superhydrophobic surfaces. Chem Soc Rev 36 1350 1368. Rao, A V, Kulkami, M M, Bhagat, S D (2(X)5) Transport of liquids using hydrophobic aerogels. J Colloid Interface Sci 285 413-418. 

Table 4.3. Molar compositions of MTMS, MeOH, water, and ammonia used in the preparation of superhydrophobic aerogels...

Preparation of Superhydrophobic Layers Deposited on the Glass Surface... 

The wettability of a particular substrate/film depends both on the chemical composition and the surface structure. Thus, the preparation of superhydrophobic coatings requires low-surface-energy functional groups such as fluorinated groups [209] and an appropriate surface topography [210,211]. As has been depicted already in the previous applications, a thorough design of a polymer blend can fulfill both requirements. 

Latthe, S.S., Gurav, A.B., Maruti, C.S.,Vhatkar, R.S., 2012. Recent progress in preparation of superhydrophobic surfaces a review. JSEMAT 2, 76. 

Wang, S., Guo, X., Xie,Y, Liu, L.,Yang, H., Zhu, R., Gong,J., Peng, L., Ding, W, 2012. Preparation of superhydrophobic silica film on Mg-Nd—Zn—Zr magnesium alloy with enhanced corrosion resistance by combining micro-arc oxidation and sol-gel method. Surf. Coat.Technol. 213,192. 

Zahner, D., Abagat.J., Svec, F., Frechet,J.M.J., Levkin, P.A., 2011. A facile approach to superhydrophilic-superhydrophobic patterns in porous polymer films. Adv. Mater. 23,3030. Zhang, F, Chen, S., Dong, L., Lei,Y, Liu, T, Yin, Y, 2011. Preparation of superhydrophobic films on titanium as effective corrosion barriers. Appl. Surf. Sci. 257,2587. 

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