Rigid Carbon-Polymer Composite

Rigid carbon-polymer composites are obtained by mixing a carbon filler (such as graphite or CNT) with nonconducting polymeric binders (epoxy, methacrylate, silicone, araldite), obtaining a soft paste that becomes rigid after a curing step. 

Being in the nanotechnology era, novel nanostructured composite materials are expected to be designed showing improved properties due to nanostructuration. Moreover, composite electrodes from expensive metals (gold, platinum, etc.) can be prepared using the NPs as conductive fillers, with enhanced properties but at lower prices compared to their pure conductor counterparts. 

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This chapter reports the main features of rigid carbon-polymer composite materials for electrochemical DNA biosensing. Novel approaches based on composites modified with biomolecules (biocomposites) and nanostructured materials (nanocomposites) for the improved biosensing of DNA are also discussed. 

In this article, the preparation and properties of typical high performance fibers are discussed, then their applications are classified and detailed. The principal classes of high performance fibers are derived from rigid-rod polymers (qv), gel-spun fibers, modified carbon fibers (qv), carbon-nanotube composite fibers, ceramic fibers, and synthetic vitreous fibers. 

These polymers can be moulded by injection or compression and can be cast as films fi om organic solvents. Their isotropic tensile moduli are well beyond the range of known isotropic polymers. They have outstanding mechanical properties, considerably better than those of the best polymeric materials, and can even be compared to structural metals [66] (see Mechanical properties). The rigid PPP backbone is presented as the microscopic equivalent of the fibre in a fibre-polymer composite, such as oriented carbon fibres embedded in a suitable polymer matrix the pendant groups play the role of the suitable polymer matrix. Applications in the design and construction of military and commercial aircraft, sports and industrial equipment and automobile components are proposed. 

It is proposed that the rigid PPP backbone reproduces at the microscopic level the fibre in a fibre-polymer composite, such as oriented carbon fibres embedded in a suitable polymer matrix the pendant groups play the role of the suitable polymer matrix. 

Over the IS years since the original Raman deformation studies upon polydiacetylene single crystals, the technique has been developed and refined to involve the study of a wide range of different high-performance polymers and other materials. These have included rigid-rod polymer fibres [19-21], carbon fibres [22-24] and ceramic fibres [2S-27]. This present chapter will concentrate upon recent research concerning the use of Raman spectroscopy to follow the deformation of aramid fibres and gel-spun polyethylene fibres and the possibility of the extension of the technique to isotropic polymers, and also the important and developing application of the method to the study of the deformation of fibres within composites. 

Yan, D. X., L. Xu, C. Chen, J. H. Tang, X. Ji, and Z. M. Li. 2012. Enhanced mechanical and thermal properties of rigid polyurethane foam composites containing graphene nanosheets and carbon nanotubes. Polym. Int. 61 1107-1114. 

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