Mechanical Properties of Glass Bead-Filled Linear Low-Density Polyethylene

Abstract

The tensile and impact properties of glass bead (GB)-filled linear low-density polyethylene (LLDPE) were studied in this article. The tensile stress–strain behaviors of GB-filled LLDPE composites do not show any obvious difference from that of pure LLDPE, but the overall mechanical properties of GB-filled LLDPE composites are improved quite a lot, which demonstrates that in a relatively small bead size range, the inorganic spherical particle can effectively increase the mechanical properties of LLDPE. The elastic modulus and the elongation to break are almost constant for various filler contents, while the yield strength greatly increases when the filler content is very low, and then remains at about that level up to a 20% filler concentration. After a sharp increase when the filler concentration is 5% by weight, the impact strength gradually increases with increasing filler content, and obtains a 40% improvement above the resin, showing significant toughening effect. Combining the effects of bead size and filler concentration studied on the mechanical properties of GB-filled LLDPE composites, it is found that for glass beads with relatively small particle size, the bead size plays a significant role, which seems to be inconsistent with some results from the literature. From investigation of the morphology of the filled specimen, it is found that though the glass beads are not surface treated, the glass beads used present quite good interfacial adhesion with the matrix LLDPE, and the distribution of the bead in the matrix is the main influencing factor on the mechanical properties of the LLDPE composites.