Polymer composites carbonaceous materials

Yazami et a/.studied the mechanism of electrolyte reduction on the carbon electrode in polymer electrolytes. Carbonaceous materials such as cokes from coal pitch and spherical mesophase and synthetic and natural graphites, were used. The change of with composition on Li, C electrodes was studied for three ranges of x in a Li/POE-LiX/carbon cell." The first step in the lithium intercalation (0 < x < 0.5) is characterized by a sharp increase of and is attributed to the formation of a bond between lithiated coke and POE. Such intercalated lithium is irreversible in the 1.5-0.5 V range. In the second step, (Ax l), lithium intercalates mainly into the coke and the film does not grow significantly, thus a slow increase of Rfl, is observed. In the third step, excess lithium is formed on the surface of the coke, and this induces a further increase in the film thickness and its resistance. 

The electrode construction is a composite consisting of a bromine resistant polymer, and various carbonaceous materials . Remarks in the patents listed at the end of the book give further information on electrode construction. 

In attempts to improve capacitance over that achieved to date in polymer-based supercapacitors, several groups have investigated EAP-based composites based on PPy [170,173-175], PANI [78,176-178], PT [160,179], PMT [166], and PFPT [160,180,181]. By using a combination of an EAP electrode and an activated carbon electrode, it is possible to produce devices with higher specific power than double-layer capacitors due to the lower equivalent series resistance [166]. In some cases, composite electrodes are a matter of necessity when chemical polymerization is used to produce insoluble polymer powders, the powders can be blended with carbonaceous material and binder. 

FuUy separated graphene platelets dispersed within matrix binder (polyaniline, carbonaceous material, amorphous or glassy carbon, or combination) solution and treated by activation or carbonization to increase total surface area. Suspension is then frozen and solvent removed by vacuum sublimation leaving a porous nanographene platelet-polymer composite. 

The application of conducting polymers as simple conductors largely falls in three categories the replacement of (1) elemental metals and metal alloys, (2) graphite and related carbonaceous materials, and (3) polymer-metal and polymer-carbon composites. Looking into the future, we must consider the possible importance of conducting polymers in each of these areas. 

This chapter is devoted to PBI composite membranes involving a polymer matrix, in this case, the PBI, and another compound in the form of filler (solid oxides, solid acids, heteropolyacids and derived heteropolysalts, pyrophosphates, ionic liquids and even carbonaceous materials). A synergic effect between the two elements always appears crucial in order to improve the membrane characteristics. As in die case of Nation membranes, the motivations for fabricating composite PBl-based membranes fall into the following classification ... 

Electrochemical biosensor performance such as sensitivity, protein stability, selectivity or reproducibility have been improved due to the use of different carbonaceous materials and combination of them. To improve the sensitivity of a electrochemical biosensor is necessaiy to increase the enzyme amount in a proper immobilization manner. CNTs are good candidates and in this regard, some authors combine carbon nanomaterials with conducting polymers, which gives rise the biosensor special properties due to the synergic effect of the individual components. The electrochemical determination of lactate by the use of lactate oxidase (LOx) based SPE platform takes advantages of the combination of MW-CNT and conductive polysulfone polymer, and such an electrochemical biosensor was successfully applied for the quantification of lactate in wine and beer. In some cases, the inconvenient is the low stability associated with the deleterious interaction of the enzyme LOx with the composite CNT/polymer substrate. 

About 70-95% of the organic matter in carbonaceous chondrites consists of an ill-defined, insoluble macromolecular material, often referred to as polymer or kerogen . A typical elemental composition for Murchison polymer (Hayatsu et al., 1980a), on a dry, ash-free basis, is C 76.5%, H 4.5%, N 2.4%, S 4.3%, and O 12.4% (by difference). 

The infiltration of carbonaceous structures by liquid silicon or silicon vapor is also an interesting technique to produce SiC components. Especially the Si-inhltration of C-structures coining from natural materials like wood offers the possibility for low cost fabrication of SiC, and has already been described in Sect. 4. Infiltration of polymer-matrix derived carbon fiber reinforced carbon is schematically drawn in Fig. 14 [255, 256]. The production of complex SiC-composite parts and components as well as big parts is possible by this route. 

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