Micromechanical and dynamic mechanical analyses for characterizing improved interfacial strength of maleic anhydride compatibilized basalt fiber/polypropylene composites

Abstract

For fiber reinforced polymer composites, it is important to obtain a good interfacial bonding between the fibers and the polymer matrix to enhance the physical properties of the composites. In particular, the mechanical and thermal properties of the composites differ depending on the interfacial bonding strength, lengths, and orientations of the fibers. We investigate the microstructural anisotropy of the basalt fiber reinforced polypropylene composites and evaluate their mechanical properties, such as elastic modulus and ultimate tensile strength in order to understand the relationship between the local anisotropy and the mechanical strength of the composites. Dynamic mechanical and thermal analyses are performed to characterize the grafting effect of maleic anhydride polypropylene on the basalt fibers. The grafting effect enhances the bonding strength between the basalt fibers and matrix and the thermomechanical properties of the composites. The elastic modulus and ultimate tensile strength of the composites with the grafting effect show enhancement compared to the composites without the grafting effect. The predictions of the elastic modulus by the Mori–Tanaka model and the ultimate tensile strength by the rule of mixture model are in good agreement with the experimental results.