Evaluation of mechanical and thermal properties of modified epoxy resin by using acacia catechu particles.

Abstract In the current study, the epoxy/amine system is reinforced by the biodegradable Acacia Catechu (AC) particles on 0.5, 1.0, 1.5 and 2.0 wt (wt.) %. The AC/epoxy composites were characterized by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), scanning electron microscope (SEM), and mechanical properties. The increased hydrogen bonding for the AC/epoxy composites was observed by FTIR spectroscopy and DSC study confirmed the improved conversion of epoxy after the AC particles addition. 14% increase in the flexural strength and 94% improved impact strength were recorded on only 1.0 wt. % AC addition due to change in morphology and crosslink density. Moreover, slightly improved thermal stabilities were also recorded due to the aromatic tannin phenol structures of AC particles. The glass transition temperature values for AC/epoxy composites were observed at 143 and 148 °C by DSC and DMA, respectively; the decline in the values can be dedicated to the flexible segment of AC particles. The SEM analysis demonstrated shear banding phenomena between particles and matrix. Highlights • Epoxy resin was modified by using the acacia catechu (AC) particles. • FTIR analysis evidenced the progress of chemical reaction between particles and matrix. • The composites have high flexural stress and bending strain. • Shear banding phenomena and plasticization also increases impact strength. • TGA showed improved thermal stability on increasing the AC amount. [ABSTRACT FROM AUTHOR]