ArticleSpectral, surface and thermal properties of poly(vinylpyrrolidone)/organomodified-TiO 2 /organo-modified-layered silicate ternary nanocomposites containing L-leucine amino acid fabricated by sonication process Abstract Since a few years ago, a topic of curiosity consists in evolving composites filled with the nanofillers to improve various properties of polymer matrix. This work aims to investigate the structure-property relationship in ternary nanocomposites containing of amorphous poly(vinylpyrrolidone) as the matrix, organo-modified-TiO 2 nanoparticles and organo-modified-montmorillonite as the nanofillers. In this regard, poly(vinylpyrrolidone)/organo-modified-TiO 2 / organo-modified-montmorillonite nanocomposites were prepared by sonication process with 10 wt% of organomodified-TiO 2 and different loadings (3, 5 and 7 wt%) of organo-modified-montmorillonite. Nanostructure characterization and dispersion capacity of nanofillers in the polymer matrix were investigated by X-ray diffraction, transmission electron microscopy and field emission scanning electron microscopy. According to these data, the nanostructure of ternary nanocomposites was predominantly intercalated. Also, incorporation of the organoclay and TiO 2 nanoparticles into the poly(vinylpyrrolidone) system was observed to have an obvious effect on the shape and size of polymer matrix. According to thermogravimetric analysis data, the presence of organo-modified-montmorillonite and organo-modifiedTiO 2 in the poly(vinylpyrrolidone) matrix, caused an improved in the thermal stability of the obtained poly(vinylpyrrolidone) nanocomposites.