Micromechanical modeling and experimental characterization of thermoplastic cork filler composites

Abstract

This study focuses on the experimental characterization and micromechanical modeling of thermoplastic cork filler composites. The research investigates the influence of granule size on the mechanical properties of composites made with a polypropylene matrix and cork granulates. Tensile, compressive, flexural, and Charpy impact tests are conducted according to ASTM standards to assess the mechanical behavior of the Cork/Polypropylene composites with different size of cork granulates (2 mm, 0.5 mm and 50 μm). Additionally, a micromechanical model is developed to provide numerical insights into the composite’s mechanical properties. Results indicate that the use of smaller cork granules (50 μm) significantly enhances tensile, compressive, and flexural properties, while maintaining Charpy impact resistance comparable to the matrix material. The Young’s Modulus exhibits an augmentation of approximately 28%, the flexural modulus demonstrates a 10% increase, and the compressive modulus manifests a notable rise of 47.7%. One-way ANOVA analysis is employed to establish the statistical significance of granule size on the modulus. Numerical simulations reveal that the spherical morphology of fillers induces isotropic characteristics in cork composite materials.