Fluorine-termination

In their study, Park et al.100 investigated the frictional properties of fluorine-terminated alkanethiol SAMs grafted to gold surfaces. The frictional properties of the system were investigated by sliding two SAMs past one another at velocities in the stick-slip regime under various external loads. The simulations yield the shear stress as and the kinetic friction coefficient pk can be estimated from the slope of a plot of as versus load, using the relationships contained in Eqs. [4] and [5]. 

Frictional Dynamics of Fluorine-Terminated Alkanethiol Self-Assembled Mono-layers. 

Hence, benzoic acids can be more appropriately considered as self-assembled rod-like mesogens with two fluorinated terminal chains (see Sect. 4.4). 

A fluorine-terminated surface is not as stable as a hydrogen-terminated one and is readily removed by a water rinse. For example, the amount of fluorine, 1%,... 

The instability of fluorine termination can readily be explained by the theory for hydrogen termination, that is, bonding with fluorine significantly weakens the back silicon-silicon bond leading to the dissolution of the atoms bonded by fluorine. 

Multi-block copolymers from a hydrophilic disul-fonated poly(arylene ether sulfone) and a hydrophobic fluorine-terminated poly(arylene ether benzoni-trile) have been synthesized [45,46],... 

To extend the hydrogen evolution potential in an aqueous media, a fluorine-terminated diamond surface is prepared in a radio frequency plasma reactor of CF-He [124]. Fluorine-terminated diamond is usually used to study electrode reactions that require high over potential. For covalent attachment of different biomolecules, hydrogen-terminated diamond electrodes are also treated with ammonia plasma to prepare the surface with terminal amine groups [125]. 

Exposure of hydrogen-terminated diamond surfaces to activated fluorine-containing gases, like HF, F2, or CF4, leads to fluorine substitution [86]. Figure 7 shows a schematic representation of a fluorine-terminated surface. 

Fig. 7 Schematic representation of a fluorine-terminated diamond surface.

Bernal and co-workers [29] characterised fluorine terminated hyper-branched polyarylenes ether phosphine oxides by GC-MS, also NMR and elemental analysis. 

FIGURE 4.8 H NMR spectrum of BPSH5-BPS5 with DFBP linkage. Black arrows indicate the disappearance of the end groups on the hydrophilic blocks after the coupling reaction with fluorine-terminated hydrophobic blocks. (Reprinted from Lee, H.S. et al.. Polymer, 49(3), 715, 2008. With permission.)... 

Mitsuya [272] examined chemisorption of ll-//-eicosafluoroundecanoic acid from hexane onto fluorine-terminated silicon wafers by XPS. The fluorinated acid was chosen as an adsorbate to distinguish the adsorbate from hydrocarbon contaminants and to minimize x-ray-induced sample damage by the chemical stability of the C—bond. 

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