In this work, the influence of the incorporation of nanoparticles (organo-modified montmorillonite Cloisite 30B) in polyamide 6 (PA6) on rigid amorphous fraction (RAF) formation had been explored employing Differential Scanning Calorimetry (DSC), Flash Differential Scanning Calorimetry (Flash DSC) and Broadband Dielectric Spectroscopy (BDS) techniques. The existence of a RAF in PA6-montmorillonite nanocomposite films is available from specific heat capacity measurement at the glass transition region of the nanocomposites. It was shown that at high C3OB content, this fraction becomes larger. Using Flash DSC, it was possible not only to measure the heat capacity step at the glass transition of the materials, but also to provide quantitative knowledge on the kinetics of crystallization and nucleation of PA6-based nanocomposites. The dielectric relaxation spectroscopy measurement was investigated, in the frequency range 0.1-10(6) Hz and varying temperature from 20 to 200 degrees C, which highlight different relaxation phenomena: the alpha dipolar relaxation, the alpha c relaxation and Max-well-Wagner-Sillars (MWS) interfacial polarizations. As C30B content increases, a MWS relaxation emerges in the nanocomposites, thus revealing the increase of RAF in the nanocomposite with high C30B content.