Micromechanical modeling of bamboo short fiber reinforced polypropylene composites

Abstract

In recent years, there has been a growing interest in injection moulded Fiber Reinforced Polymer (FRP) composites, particularly with the natural fiber reinforcement due to their renewability and eco friendliness. In many of the applications, stiffness and strength are of prime importance in designing of injection moulded engineering parts. Determination of elastic modulus will give the designer flexibility to design the part geometry depending on stiffness requirement for particular application. This paper discusses micromechanical modeling of bamboo short fiber reinforced polypropylene composites. Bamboo polypropylene composites (BPC) were prepared by reinforcing polypropylene homopolymer matrix with short bamboo fibers. Composites with five different reinforcement percentages (10, 20, 30, 40, and 50 wt%) were prepared and tensile test samples were injection moulded. Tensile elastic modulus and strengths of bamboo composites were measured according to ASTM standard. Various micromechanical theoretical models were studied to find best possible model that correlates well with the experimental results. Elastic Modulus predicted by “Halpin-Tsai” model was in close agreement with the experimentally measured values. Strength predicted by “Kelly-Tyson” model also matched very well with the experimental values. Micromechanic-based semi analytical model “Mori–Tanaka” in Digimat-MF (mean-field homogenization) and numerical finite-element modeling (FEM) of BPC using the concept of representative volume element (RVE) have also been studied and results are compared with experimentally measured values.