A study on visco-elastic, thermal and mechanical characteristics of injection molded ABS/graphite composite

Abstract

Acrylonitrile Butadiene Styrene (ABS) materials have been widely used in automotive and other manufacturing industries. To meet the specific requirements of industry the ABS materials are enhanced by adding fillers through compounding. Very few works are found for the improvement of viscoelastic and thermal characteristics of ABS material. This work is focused to prepare the thermoplastic composites of ABS with graphite filler and to analyze the dynamic mechanical, thermal and mechanical properties of composites. Thermoplastic composites were prepared with three different weight ratios (3, 6 and 9%) of graphite powder with ABS by employing a twin-screw extruder and the scanning electron microscopy (SEM) images confirmed the proper mixing of filler material with the matrix and the samples were prepared using injection molding machine. The viscoelastic properties of the composites were investigated through dynamic mechanical analysis (DMA) with three different frequencies of (0.5, 1 and 2) Hz and the DMA results indicate that the damping properties were significantly influenced by the presence of graphite particles in ABS. It was observed that the storage modulus (E’) is higher at the frequency of 2 Hz compared to the other two frequencies (0.5 and 1) Hz, but the loss modulus was almost the same at all three frequencies. The thermal stability and mass losses of the prepared samples, thermal gravimetric analysis (TGA) was performed and the TGA graphs showed the improvement in the thermal characteristics of neat ABS due to the addition of graphite filler. The DSC thermograms of neat ABS and ABS/graphite composites indicate that the glass transition temperatures of ABS/graphite composites were increased. The tensile strength increases up to 6 wt% of graphite and drastically drops at 9 wt% of the filler content. But the flexural strength of the ABS/graphite composites were reduced as the weight percentage of graphite content increases.