Fluorinated tails

If Lp = Lh, the monolayer smectic Ai phase is formed. In the case that Lp > Lh, the layer spacing d exceeds the molecular length L, which corresponds to the formation of the smectic A phase (Fig. lla,b). In the opposite case, Lp < Lh, the layer spacing is less than L, and the flexible hydrocarbon chains just All the space which is determined by the fluorinated tails (Fig. 10c). 

Fig. 11a,b. Examples of one and two-dimensional structures for terminally fluorinated mesogens a antiparallel dimeric layering for the compounds with one terminal fluorinated tail (Diele et al. [38]) b two-dimensional (columnar) packing observed for the swallow-tailed fluorinated compounds solid lines indicate two-dimesional rectangular lattice (Lose et al. [41])... 

Recently it has been demonstrated by Guittard et al. that the electrochemical polymerization of semifluorinated thiophenes (226) [407], 3,4-ethylenediox-ythiophenes (227) [408], fluorenes [408], and 3,4-alkylenedioxypyrroles (230) [409] allowed the deposition of semiconducting polymer films with excellent antiwetting properties (superhydrophobic and lipophobic, see Fig. 73). Additional aromatics inserted between fluorinated tail and polymer chain (compounds 228, 231) improve mesogenity and in this way decrease the mobility of the Rp-chains, preorganize the molecules, and thus improve the antiwetting properties [388, 410]. 

Upham, B. L., Deocamp, N. D., Wurl, B., Troskp, J. E. Inhibition of gap junction intercellular communication by perfluorinated fatty acids is dependent on the chain length of the fluorinated tail. Int. J. Cancer, 78 491 95 (1998). 

Fluorinated compounds are highly soluble - fluorinated tails increase solubility. 

Zhang X, Tan D, Li J, Tan H, Fu Q. Synthesis and hemocompatibity evaluation of segmented polyurethane end-capped with both a fluorine tail and phosphatidylcholine polar head groups. Biofouhng 2011 27(8) 919—30. 

H. Bellanger, T. Darmanin and F. Guittard, Surface structuration (micro and/ or nano) governed by the fluorinated tail lengths toward superoleophobic surfaces, Langmuir, 28,186-192 (2012). 

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