Optical properties of nanocomposites based on polymers and metal nanoparticles

Resumo

The optical properties of nanocomposites of metal nanoparticles and polymers of two types have been studied. Gold and silver nanoparticles were obtained by laser ablation of corresponding metal targets in acetone and chloroform. The thus formed colloidal solutions were used to prepare nanocomposites of these nanoparticles in polymer matrices of polymethylmethacrylate (PMMA) and fluorine-containing polymer LF-32. The polymer matrix is found to promote aggregation of the metal nanoparticles under study into elongated chains. In turn, metal nanoparticles affect the polymer matrix. In the case of PMMA, suppression of the vibrational peaks of polymer in the low-frequency region of its Raman spectrum occurs. In the case of LF-32, gold and silver nanoparticles amplify the Raman signal of the polymer matrix. In addition, the Raman spectra of nanocomposites indicate aggregation of disordered carbon around the nanoparticles obtained by laser ablation in organic solvents. The possibilities of studying the ultrafast (about 1 ps) optical response of the nanocomposites obtained in order to use it in photonics elements are discussed.