Tailoring the performance of bamboo filler reinforced epoxy composite: insights into fracture properties and fracture mechanism

Due to the graded micro-structure and high specific strength-stiffness, bamboo micro fillers are systematically utilized in reinforcing different thermoset and thermoplastic polymers as replacement of conventional glass and carbon fillers. In this work, micro-size bamboo particle fillers are reinforced in specific grade' thermoset epoxy matrix and its fracture properties has been evaluated by following linear elastic fracture mechanics. To enhance its compatibility with the polymer matrix and to reduce the hydrophilicity, the bamboo micro fillers are surface modified through alkaline treatment. The extent of surface modification and removal of lower weight polymers from filler surface are examined and established by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction analysis and thermogravimetric analysis. The fracture properties of bamboo-epoxy composite material are observed to be increasing with the addition of bamboo fillers and the maximum value of fracture toughness is 0.678MPa.m(0.5) which is 32% higher than the same for neat epoxy samples. In addition, the mechanisms of notch initiated fracture propagation have also been explained for the understanding of stress singularity present at the preexisted crack tip.