Effects of vibration force field on structure and properties of HDPE/CaCO3 nanocomposites

HDPE/CaCO3 nanocomposites were prepared using an electromagnetic dynamic extruder, which introduces a vibration force field into the whole extrusion process. Effects of vibration force field on the morphology, the crystallization behavior and mechanical properties of HDPE/CaCO3 nanocomposites were investigated by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD) and mechanical testing. SEM examinations show that the nanocomposites extruded in the presence of a vibration force field have a smaller average particle diameter and a narrower particle size distribution, compared with those in the absence of vibration. Correspondingly, they exhibit a higher melting temperature and a smaller average crystal size, which was determined by DSC and WAXD, respectively. Both the tensile and impact strengths of HDPE/CaCO3 nanocomposites increase and then decrease with vibration intensity, reaching a maximum when the vibration amplitude is 80 mu m and the frequency is 10 Hz. (c) 2005 Elsevier Ltd. All rights reserved.