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The Raman spectroscopy have allowed us to perform studies on singlewalled nanotubes (SWNT's) produced by following methods: electric arc, laser ablation and solar energy. As this characterization method provides a great deal of informations, we will present a comparison between the nanotubes produced by all these processes and the influence of some synthesis parameters. By using spin casting, we have produced thin films of PMMA-SWNT's for different concentrations. Then, we have characterized these new materials by Raman spectroscopy. The aim of these investigations is to get information on the possible interactions between these two materials. In particular, we have studied the evolution of the composites films spectra as a function of the nanotubes concentration in the polymer.

Singlewalled carbon nanotubes (SWNT's) prepared by the electric arc method are characterized by means of spectroscopic techniques, mainly Transmission Electron Microscopy and resonance Raman scattering. TEM observations reveal the existence of nïckel particles embedded in an amorphous carbon matrix, but also a large concentration of SWNT's, whose average diameter can be estimated to be near 1.3 nm, arranged in bundles. Raman spectra recorded on the same samples exhibit several features, mainly consisting of two groups. On one hand, in the high frequency region, several bands are observed in the range 1500 - 1600 cm−1, corresponding to a splitting of the E2g2 vibrational mode of graphite. On the other hand, several components are recorded between 150 and 240 cm−1, reflecting a distribution in the diameter of the SWNT's. A systematic study of the ≪collaret≫, from which samples are extracted, is also presented.