Surface ether linkages

Figure 54. Peculiar surface chemistry of BOB anion on graphitic anode material XPS C Is spectra for a graphitic anode surface cycled in LiBOB- and LiPF6-based electrolytes. The peaks were resolved into three major contributions representing (1) hydrocarbon at 284.5 eV, (2) oligo-ether linkages at 286.5 eV, and (3) lithium alkyl carbonates at 289.37 eV, respectively. (Reproduced with permission from ref 489 (Figure 3). Copyright 2003 The Electrochemical Society.)...

One surprise in Arai s results is perhaps the anodic stability of the ether-based solvent MFE, which remained stable anodically at up to 4.2 V on the LiCo02 surface. Considering the numerous previous reports that the ether linkage is oxidatively decomposed near 4.0 V, " 5J8,93 might attribute this additional stability of MFE to the fluorination of the molecule. 

The electrochemical behavior of lithium electrodes in a variety of polymeric electrolyte systems was studied extensively by a number of groups, including Scrosati et al. [390-392], Panero et al. [393], Abraham et al. [394-396], Osaka et al. [397-398], Watanabe et al. [399-401], Peled et al. [402], It is clear that there are surface reactions between the lithium and all of the polymeric systems mentioned above. It has already been clearly shown that the ether linkage is attacked by lithium, resulting in the formation of Li alkoxy species [149], Hence, it is expected the PEO-based polymers also react with Li surfaces. Spec-troelectrochemical studies of the Li-PEO system by Scherson et al. [177] provide some evidence for this possibility. Besides the polymers, the polymeric electrolyte systems contain salts with anions such as Aslv,, S03CF3, NlSOTTO),, ... 

These esters were prepared from aqueous solutions of tri-ethanolamine and PE-61.PE-62 and PE-64 block copolymers. When higher monoesters of the surface active agents were utilized, excellent antiwear properties were observed. Again, the configuration of the ether linkage in relationship to the rest of the molecule plays a role in this compound s effectiveness. Table 2.4 shows properties of cutting fluids from ricinoleic acid oligomer esters with triethanolamine. The same values from fluids made from polymeric non-ionic surfactants are shown in Table 2.5. 

Fig. 7 Schematic of the tyrosine and phenolic monomers studied, DELT and DEDT self-assembly, and the adsorption vs electropolymerization processes occurring at the Pt electrode surface. For simplicity, we have not attempted to indicate the - 0-ether linkage products that may also represent a minor fraction of the linkages foimd in the electropolymerized phenolic film products. This figure was reprinted with permission from [71]...

In HEC-thickened formulations, low-shear-rate viscosities increase with decreasing latex particle size. This effect has been a major limitation in formulating small-particle latices. The phenomenon appears to arise from electro viscous, hydration, or flocculation effects, not a depletion layer mechanism. Associative thickeners achieve efficient viscosity in coating formulations via participation in synthesis and formulation surfactant micelles to form pseudo macromolecules and via an ion-dipole interaction between the cations of surface carboxylate groups on the latex and the ether linkages of the associative thickener. Generally, an excess of synthesis surfactant is found in the production of small-particle latices. The achievement of lower viscosities in small-particle ( 100 nm) latex coatings thickened with associative thickener appears to occur by extensive disruption of the polymer hydrophobe s participation in intermicellar networks. 

Thus this type of epoxy resin contains a maximum of two epoxide rings at the ends of the molecule and a number (which may be zero) of hydroxyl groups along the chain. These groups make the resin a polar one and ensure good adhesion to polar or metallic surfaces. The next thing to note is that the polymer chain contains only carbon-carbon and ether linkages. Both are very stable. We have seen the C-C stability in acrylic polymers, and in the preparation of nitrocellulose... 

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