The present work focuses on the modelling of mechanical behaviour of polyamide based nanocomposite films whose tensile properties were correlated to the structural changes promoted by the biaxial deformation imposed during the film blowing process. It is well known that the nanocomposite properties are strictly related to the microstructure developed during the processing. The ideal situation of full exfoliation, dispersion and orientation of silicate layers in the polymer matrix is not easily achieved in melt compounding process. Actually, a more common situation is represented by partially exfoliated and intercalated morphology. Therefore, a 3D-FEM numerical model which takes into account a mixed exfoliated and intercalated nanostructure has been used to fit the experimental mechanical results. In particular, the algorithm imposes periodic boundary conditions, so that the mean value of the elastic constants, for even RVEs containing very few particles, is close to the exact value for large composite volume. Comparison of simulation results with experimental data has confirmed the reliability of the numerical simulation method used in the present study.
Characterization and modelling of mechanical properties of polymer/clay nanocomposites by film blowing
NADDEO, FRANCESCO;GAROFALO, EMILIA;CRICRI', Gabriele;INCARNATO, Loredana
2008-01-01
Abstract
The present work focuses on the modelling of mechanical behaviour of polyamide based nanocomposite films whose tensile properties were correlated to the structural changes promoted by the biaxial deformation imposed during the film blowing process. It is well known that the nanocomposite properties are strictly related to the microstructure developed during the processing. The ideal situation of full exfoliation, dispersion and orientation of silicate layers in the polymer matrix is not easily achieved in melt compounding process. Actually, a more common situation is represented by partially exfoliated and intercalated morphology. Therefore, a 3D-FEM numerical model which takes into account a mixed exfoliated and intercalated nanostructure has been used to fit the experimental mechanical results. In particular, the algorithm imposes periodic boundary conditions, so that the mean value of the elastic constants, for even RVEs containing very few particles, is close to the exact value for large composite volume. Comparison of simulation results with experimental data has confirmed the reliability of the numerical simulation method used in the present study.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.