Strengthening acrylonitrile-butadiene-styrene (ABS) with nano-sized and micron-sized calcium carbonate

ABS was reinforced by both micron-sized (MCC) and nano-sized precipitated calcium carbonate (NPCC) particles through melt compounding. The MCC/ABS composites were found to have higher modulus but lower tensile and impact strength than neat ABS. In contrast, NPCC increased modulus of ABS whilst maintained or even increased its impact strength for a certain NPCC loading range. SEM examinations revealed that NPCC particles/agglomerates were distributed in much smaller sizes in the composites than its MCC counterparts. The larger interfacial area between NPCC and ABS and cavitation-induced shear yielding in the ligament are believed to be the main reasons of the mechanical property improvement of the NPCC/ABS composites. NPCC/ABS also shows completely different rheological behavior from MCC/ABS, such as the loss of Newtonian region, high G′ at low frequencies and the appearance of yield phenomenon. A NPCC network structure was believed to be formed in the composites and induced these pseudo-solid-like rheological behaviors.