An investigation on the toughening behavior and morphology of acrylonitrile butadiene styrene/polybutylene terephthalate blends reinforced by carbon nanotubes

Acrylonitrile butadiene styrene (ABS) and polybutylene terephthalate (PBT) polymers are widely exploited polymers in the plastics industry. In this research, PBT polymer is added into ABS polymer as a second phase due to its good fluidity and some superior mechanical characteristics. Carbon nanotubes (CNTs) are added as a reinforcement into the ABS/PBT polymer blend (80/20). Standard samples of mechanical tests including tensile, flexural, and impact were made by injection molding and standard samples of fracture tests were made by hot press method. The essential work of fracture (EWF) method was used to check fracture toughness. The presence of PBT into ABS improved its tensile and flexural strength while it diminished the impact strength and fracture toughness of ABS. The addition of carbon nanotubes into ABS/PBT blends increased its tensile and flexural strength, impact resistance as well as fracture toughness. The results of microscopic tests demonstrate a relatively uniform distribution of carbon nanotubes in the polymer blend. In addition, the morphological observations illustrate a rather proper adhesion between carbon nanotubes and the polymeric matrix. As importantly, investigations on the fractured sections of fracture specimens revealed that the nanocomposites containing CNTs have a tendency toward a ductile failure in comparison with ABS/PBT polymer blend.