Micromechanical modeling of isotropic elastic behavior of semicrystalline polymers

Considering semicrystalline polymers as heterogeneous materials consisting of an amorphous phase and crystallites, several micromechanical models have been tested to predict their elastic behavior. Two representations have been considered: crystallites embedded in a matrix and a layered-composite aggregate. Several homogenization schemes have been used in these representations. Firstly, comparisons between the models and experiments show that the micromechanics approach applies at this scale. Secondly, the results differ according to the rubbery or glassy state of the amorphous phase. Finally, the results suggest that the spherulitic mesostructure does not affect the material behavior while infinitesimal elastic strains are considered.

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