Morphology and physical properties of composites based on high-density polyethylene/propylene-ethylene random copolymers blends and carbon black

Abstract

High-density polyethylene (HDPE) composites containing propylene-ethylene random copolymers (PEC) elastomer and carbon black (CB) were prepared by melt blending in an effort to obtain excellent balance of properties. HDPE matrix and PEC elastomer were immiscible, and CB fillers were selectively located in HDPE matrix. The introduction of CB fillers into the HDPE/PEC blend significantly improved the viscoelasticity of the composite melts. Percolation network of CB particles was formed at CB content of 5 wt%, which consequently largely improved the conductivity of composites, and the surface resistance decreased to 106 Ω (square)−1, equal to the antistatic range. DSC results suggested that CB with a content more than 5 wt% showed nucleation effect, improving the degree of crystallinity of HDPE. Moreover, the incorporation of CB improved stiffness of composites, and decreased ductility compare with HDPE/PEC blend. The combination of adjustable conductivity and mechanical properties, as well as improved melt viscoelasticity wold further broaden the application fields of HDPE based composites.

Keywords

• High-density polyethylene
• Propylene-ethylene random copolymers
• Composites
• Carbon black