Maria Ines Tavares

By Maria Inês Bruno Tavares, Emerson Oliveira da Silva, Paulo Rangel Cruz da Silva and Lívia Rodrigues de Menezes

The development of polymer nanocomposites has advanced, especially due to their new properties after nanoparticle incorporation. Many nanocomposites composed of synthetic polymers and/or biopolymers have been studied after incorporation of a diversity of nanoparticles, which differ in form, shape, surface area and chemical organization. In this chapter, some examples of nanocomposites based on poly-vinyl alcohol (PVA); polycarbonate (PC) and matrixes of dental resins are presented. These nanocomposites could be obtained by three basic methods: in situ polymerization, solution casting and melt extrusion. The best method is determined by the relation and route to the polymer-nanoparticle pair. The dispersion and distribution of nanoparticles in the polymer matrix is the key to obtaining new materials with synergism of compounds properties. This synergism depends on how strong is the intermolecular interaction between the polymer matrix and nanoparticles. The evaluation of new nano systems can be done by different techniques, usually microscopy, X-ray diffraction, thermal analysis and so on. Low-field NMR relaxometry has been used to evaluate polymer nanocomposites. This technique provides valuable information related to the interaction of the nanoparticles with the polymer matrix, and it also indicates the dispersion and distribution of these nanoparticles in the matrix.

Part of the book: Nanostructured Materials

By Maria Ines Bruno Tavares

The nuclear magnetic resonance (NMR) spectroscopy is a very powerful tool in the chemical characterization, both in solution and in solid state. With the development of NMR spectrometers more potent field, employing radio frequency pulse, provided the development of studies on materials, especially amorphous materials. Thus, there was a need to develop techniques to obtain spectra in solid state with high resolution in comparison to those obtained in solution. Therefore, the study of polymers and polymeric materials could be developed quickly as a result a lot of information about the structure-property could be obtained with more details. The use of NMR in the solid state has become particularly important in the study of amorphous materials, as well as in the study of crystal structures, and permits us to detect different constituents present in material. This chapter covers the basic solid-state NMR techniques that provide important information on sample molecular behavior because they are powerful and versatile tools to evaluate polymer and complex materials like nanomaterials.

Part of the book: Spectroscopic Analyses